31 files changed, 28306 insertions, 0 deletions

diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..6833f05
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1,3 @@
+* text=auto
+*.txt text
+*.md text
diff --git a/34114-8.txt b/34114-8.txt
new file mode 100644
index 0000000..a6148ad
--- /dev/null
+++ b/34114-8.txt
@@ -0,0 +1,9326 @@
+The Project Gutenberg EBook of Soap-Making Manual, by E. G. Thomssen
+
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever.  You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at www.gutenberg.org
+
+
+Title: Soap-Making Manual
+       A Practical Handbook on the Raw Materials, Their
+       Manipulation, Analysis and Control in the Modern Soap Plant.
+
+Author: E. G. Thomssen
+
+Release Date: October 22, 2010 [EBook #34114]
+
+Language: English
+
+Character set encoding: ISO-8859-1
+
+*** START OF THIS PROJECT GUTENBERG EBOOK SOAP-MAKING MANUAL ***
+
+
+
+
+Produced by David Clarke, Josephine Paolucci and the Online
+Distributed Proofreading Team at https://www.pgdp.net. (This
+file was produced from images generously made available
+by The Internet Archive/American Libraries.)
+
+
+
+
+
+
+
+Soap-Making Manual
+
+A practical handbook on the raw materials, their manipulation, analysis
+and control in the modern soap plant.
+
+By
+
+_E. G. Thomssen, Ph. D._
+
+ILLUSTRATED
+
+
+NEW YORK
+
+D. VAN NOSTRAND COMPANY
+
+EIGHT WARREN STREET
+
+1922
+
+COPYRIGHT 1922
+
+BY
+
+D. VAN NOSTRAND COMPANY
+
+Printed in the United States of America
+
+       *       *       *       *       *
+
+Transcriber's note:
+
+This is a series of articles collected into a book. There are
+differences in spelling and punctuation in the different chapters (e.g.
+cocoanut in one chapter and coconut in another). These differences were
+left in the text as they appeared.
+
+For Text: A word surrounded by a tilde such as ~this~ signifies that
+the word is bolded in the text. A word surrounded by underscores like
+_this_ signifies the word is italics in the text.
+
+For numbers and equations: Parentheses have been added to clarify
+fractions. Underscores before bracketed numbers in equations denote a
+subscript.
+
+Minor typos have been corrected and footnotes moved to the end of the
+chapters.
+
+       *       *       *       *       *
+
+
+PREFATORY NOTE.
+
+
+The material contained in this work appeared several years ago in serial
+form in the American Perfumer and Essential Oil Review. Owing to the
+numerous requests received, it has been decided to now place before
+those interested, these articles in book form. While it is true that the
+works pertaining to the soapmaking industry are reasonably plentiful,
+books are quite rare, however, which, in a brief volume, will clearly
+outline the processes employed together with the necessary methods of
+analyses from a purely practical standpoint. In the work presented the
+author has attempted to briefly, clearly, and fully explain the
+manufacture of soap in such language that it might be understood by all
+those interested in this industry. In many cases the smaller plants find
+it necessary to dispense with the services of a chemist, so that it is
+necessary for the soapmaker to make his own tests. The tests outlined,
+therefore, are given as simple as possible to meet this condition. The
+formulae submitted are authentic, and in many cases are now being used
+in soapmaking.
+
+In taking up the industry for survey it has been thought desirable to
+first mention and describe the raw materials used; second, to outline
+the processes of manufacture; third, to classify the methods and
+illustrate by formulae the composition of various soaps together with
+their mode of manufacture; fourth, to enumerate the various methods of
+glycerine recovery, including the processes of saponification, and,
+fifth, to give the most important analytical methods which are of value
+to control the process of manufacture and to determine the purity and
+fitness of the raw material entering into it.
+
+It is not the intention of the author to go into great detail in this
+work, nor to outline to any great extent the theoretical side of the
+subject, but rather to make the work as brief as possible, keeping the
+practical side of the subject before him and not going into concise
+descriptions of machinery as is very usual in works on this subject.
+Illustrations are merely added to show typical kinds of machinery used.
+
+The author wishes to take this opportunity of thanking Messrs. L. S.
+Levy and E. W. Drew for the reading of proof, and Mr. C. W. Aiken of the
+Houchin-Aiken Co., for his aid in making the illustrations a success, as
+well as others who have contributed in the compiling of the formulae for
+various soaps. He trusts that this work may prove of value to those
+engaged in soap manufacture.
+
+E. G. T.
+
+January, 1922
+
+
+
+
+TABLE OF CONTENTS.
+
+
+CHAPTER I.                                                      Page.
+
+RAW MATERIALS USED IN SOAP MAKING                                1-30
+
+  1. Soap Defined                                                   1
+
+  2. Oils and Fats                                                1-2
+
+  3. Saponification Defined                                       2-3
+
+  4. Fats and Oils Used in Soap Manufacture                       3-4
+    Fullers' Earth Process for Bleaching Tallow                   4-6
+    Method for Further Improvement of Color in Tallow               6
+    Vegetable Oils                                                6-9
+    Chrome Bleaching of Palm Oil                                 9-12
+    Air Bleaching of Palm Oil                                   12-16
+
+  5. Rancidity of Oils and Fats                                 16-18
+    Prevention of Rancidity                                        18
+
+  6. Chemical Constants of Oils and Fats                        18-19
+
+  7. Oil Hardening or Hydrogenating                             19-21
+
+  8. Grease                                                     21-22
+
+  9. Rosin (Colophony, Yellow Rosin, Resina)                    22-23
+
+  10. Rosin Saponification                                      23-24
+
+  11. Naphthenic Acids                                          24-25
+
+  12. Alkalis                                                   25-26
+    Caustic Soda                                                   26
+    Caustic Potash                                              26-28
+    Sodium Carbonate (Soda Ash)                                 28-29
+    Potassium Carbonate                                            29
+
+  13. Additional Material Used in Soap Making                   29-30
+
+
+CHAPTER II.
+
+CONSTRUCTION AND EQUIPMENT OF A SOAP PLANT                      31-34
+
+
+CHAPTER III.
+
+CLASSIFICATION OF SOAP MAKING METHODS                           35-46
+
+  1. Full Boiled Soaps                                          36-42
+
+  2. Cold Process                                               43-44
+
+  3. Carbonate Saponification                                   45-46
+
+
+CHAPTER IV.
+
+CLASSIFICATION OF SOAPS                                        47-104
+
+  1. Laundry Soap                                                  48
+    Semi-Boiled Laundry Soap                                    49-50
+    Settled Rosin Soap                                          50-54
+
+  2. Chip Soap                                                  54-55
+    Cold Made Chip Soap                                         55-56
+    Unfilled Chip Soap                                             56
+
+  3. Soap Powders                                               56-59
+    Light Powders                                               60-61
+
+  4. Scouring Powders                                              61
+
+  5. Scouring Soap                                              61-62
+
+  6. Floating Soap                                              62-65
+
+  7. Toilet Soap                                                65-68
+    Cheaper Toilet Soaps                                        68-69
+    Run and Glued-up Soaps                                      69-71
+    Curd Soap                                                   71-72
+    Cold Made Toilet Soaps                                      72-73
+    Perfuming and Coloring Toilet Soaps                         73-75
+    Coloring Soap                                               75-76
+
+  8. Medicinal Soaps                                            76-77
+    Sulphur Soaps                                                  77
+    Tar Soap                                                       77
+    Soaps Containing Phenols                                    77-78
+    Peroxide Soap                                                  78
+    Mercury Soaps                                                  78
+    Less Important Medicinal Soaps                              78-79
+
+  9. Castile Soap                                               79-81
+
+  10. Eschweger Soap                                            81-82
+
+  11. Transparent Soap                                          82-84
+    Cold Made Transparent Soap                                  84-87
+
+  12. Shaving Soaps                                             87-90
+    Shaving Powder                                                 90
+    Shaving Cream                                               90-93
+
+  13. Pumice or Sand Soaps                                      93-94
+
+  14. Liquid Soaps                                              94-95
+
+  15. Use of Hardened Oils in Toilet Soaps                      96-98
+
+  16. Textile Soaps                                                98
+    Scouring and Fulling Soaps for Wool                        98-100
+    Wool Thrower's Soap                                       100-101
+    Worsted Finishing Soaps                                       101
+    Soaps Used in the Silk Industry                           101-103
+    Soaps Used for Cotton Goods                               103-104
+
+  17. Sulphonated Oils                                        104-105
+
+
+CHAPTER V.
+
+GLYCERINE RECOVERY                                            105-126
+
+  1. Methods of Saponification                                105-106
+     Recovery of Glycerine from Spent Lye                     106-113
+     Twitchell Process                                        113-118
+     Autoclave Saponification                                     118
+     Lime Saponification                                      118-120
+     Acid Saponification                                      120-121
+     Aqueous Saponification                                       121
+     Splitting Fats with Ferments                             121-123
+     Krebitz Process                                          123-125
+
+  2. Distillation of Fatty Acids                              125-126
+
+
+CHAPTER VI.
+
+ANALYTICAL METHODS                                            127-164
+
+  1. Analysis of Oils and Fats                                    128
+     Free Fatty Acids                                         128-130
+     Moisture                                                     130
+     Titer                                                    130-132
+     Determination of Unsaponifiable Matter                   132-133
+     Test for Color of Soap                                   133-134
+     Testing of Alkalis Used in Soap Making                   134-137
+
+  2. Soap Analysis                                            137-138
+     Moisture                                                 138-139
+     Free Alkali or Acid                                      139-142
+     Insoluble Matter                                             143
+     Starch and Gelatine                                      143-144
+     Total Fatty and Resin Acids                                  144
+     Determination of Rosin                                   144-147
+     Total Alkali                                             147-148
+     Unsaponifiable Matter                                        148
+     Silica and Silicates                                     148-149
+     Glycerine in Soap                                        149-150
+     Sugar in Soap                                                150
+
+  3. Glycerine Analysis                                       150-151
+     Sampling                                                     151
+     Analysis                                                 151-154
+     Acetin Process for the Determination of Glycerol         155-156
+     The Method                                               156-159
+     Ways of Calculating Actual Glycerol Contents             159-160
+     Bichromate Process for Glycerol Determination
+       Reagents Required                                      160-161
+     The Method                                               161-162
+     Sampling Crude Glycerine                                 162-164
+
+
+CHAPTER VII
+
+STANDARD METHODS FOR THE SAMPLING AND ANALYSIS OF
+COMMERCIAL FATS AND OILS                                      165-195
+
+  1. Scope, Applicability and Limitations of the Methods      165-166
+    Scope                                                         165
+    Applicability                                                 166
+    Limitations                                                   166
+    Sampling                                                  166-169
+    Tank Cars                                                 166-167
+    Barrels, Tierces, Casks, Drums, and Other Packages            168
+
+  2. Analysis                                                 169-183
+    Sample                                                        169
+    Moisture and Volatile Matter                              170-172
+    Insoluble Impurities                                      172-173
+    Soluble Mineral Matter                                        173
+    Free Fatty Acids                                              174
+    Titer                                                     174-175
+    Unsaponifiable Matter                                     176-177
+    Iodine Number-Wijs Method                                 177-181
+    Saponification Number (Koettstorfer Number)                   181
+    Melting Point                                             181-182
+    Cloud Test                                                182-184
+
+  3. Notes of the Above Methods                               184-196
+    Sampling                                                      183
+    Moisture and Volatile Matter                              184-187
+    Insoluble Impurities                                          187
+    Soluble Mineral Matter                                    187-188
+    Free Fatty Acid                                           188-189
+    Titer                                                         189
+    Unsaponified Matter                                       190-193
+    Melting Point                                             193-196
+
+Plant and Machinery                                           198-219
+    Illustrations of Machinery and Layouts of the Plant
+    of a Modern Soap Making Establishment                     198-219
+
+Appendix                                                      219-237
+
+    Useful Tables
+
+Index                                                             239
+
+
+
+
+CHAPTER I
+
+Raw Materials Used in Soap Making.
+
+
+Soap is ordinarily thought of as the common cleansing agent well known
+to everyone. In a general and strictly chemical sense this term is
+applied to the salts of the non-volatile fatty acids. These salts are
+not only those formed by the alkali metals, sodium and potassium, but
+also those formed by the heavy metals and alkaline earths. Thus we have
+the insoluble soaps of lime and magnesia formed when we attempt to wash
+in "hard water"; again aluminum soaps are used extensively in polishing
+materials and to thicken lubricating oils; ammonia or "benzine" soaps
+are employed among the dry cleaners. Commonly, however, when we speak of
+soap we limit it to the sodium or potassium salt of a higher fatty acid.
+
+It is very generally known that soap is made by combining a fat or oil
+with a water solution of sodium hydroxide (caustic soda lye), or
+potassium hydroxide (caustic potash). Sodium soaps are always harder
+than potassium soaps, provided the same fat or oil is used in both
+cases.
+
+The detergent properties of soap are due to the fact that it acts as an
+alkali regulator, that is, when water comes into contact with soap, it
+undergoes what is called hydrolytic dissociation. This means that it is
+broken down by water into other substances. Just what these substances
+are is subject to controversy, though it is presumed caustic alkali and
+the acid alkali salt of the fatty acids are formed.
+
+
+OILS AND FATS.
+
+There is no sharp distinction between fat and oil. By "oil" the layman
+has the impression of a liquid which at warm temperature will flow as a
+slippery, lubricating, viscous fluid; by "fat" he understands a greasy,
+solid substance unctuous to the touch. It thus becomes necessary to
+differentiate the oils and fats used in the manufacture of soap.
+
+Inasmuch as a soap is the alkali salt of a fatty acid, the oil or fat
+from which soap is made must have as a constituent part, these fatty
+acids. Hydrocarbon oils or paraffines, included in the term "oil," are
+thus useless in the process of soap-making, as far as entering into
+chemical combination with the caustic alkalis is concerned. The oils and
+fats which form soap are those which are a combination of fatty acids
+and glycerine, the glycerine being obtained as a by-product to the
+soap-making industry.
+
+
+NATURE OF A FAT OR OIL USED IN SOAP MANUFACTURE.
+
+Glycerine, being a trihydric alcohol, has three atoms of hydrogen which
+are replaceable by three univalent radicals of the higher members of the
+fatty acids, _e. g._,
+
+                OH                       OR
+    C_{3} H_{5} OH + 3 ROH = C_{3} H_{5} OR + 3 H_{2}O
+                OH                       OR
+
+Glycerine plus 3 Fatty Alcohols equals Fat or Oil plus 3 Water.
+
+Thus three fatty acid radicals combine with one glycerine to form a true
+neutral oil or fat which are called triglycerides. The fatty acids which
+most commonly enter into combination of fats and oils are lauric,
+myristic, palmitic, stearic and oleic acids and form the neutral oils or
+triglycerides derived from these, _e. g._, stearin, palmatin, olein.
+Mono and diglycerides are also present in fats.
+
+
+SAPONIFICATION DEFINED.
+
+When a fat or oil enters into chemical combination with one of the
+caustic hydrates in the presence of water, the process is called
+"saponification" and the new compounds formed are soap and glycerine,
+thus:
+
+               OR                       OH
+    C_{3}H_{5} OR + 3 NaOH = C_{3}H_{5} OH + 3 NaOR
+               OR                       OH
+
+Fat or Oil plus 3 Sodium Hydrate equals Glycerine plus 3 Soap.
+
+It is by this reaction almost all of the soap used today is made.
+
+There are also other means of saponification, as, the hydrolysis of an
+oil or fat by the action of hydrochloric or sulfuric acid, by autoclave
+and by ferments or enzymes. By these latter processes the fatty acids
+and glycerine are obtained directly, no soap being formed.
+
+
+FATS AND OILS USED IN SOAP MANUFACTURE.
+
+The various and most important oils and fats used in the manufacture of
+soap are, tallow, cocoanut oil, palm oil, olive oil, poppy oil, sesame
+oil, soya bean oil, cotton-seed oil, corn oil and the various greases.
+Besides these the fatty acids, stearic, red oil (oleic acid) are more or
+less extensively used. These oils, fats and fatty acids, while they vary
+from time to time and to some extent as to their color, odor and
+consistency, can readily be distinguished by various physical and
+chemical constants.
+
+Much can be learned by one, who through continued acquaintance with
+these oils has thoroughly familiarized himself with the indications of a
+good or bad oil, by taste, smell, feel and appearance. It is, however,
+not well for the manufacturer in purchasing to depend entirely upon
+these simpler tests. Since he is interested in the yield of glycerine,
+the largest possible yield of soap per pound of soap stock and the
+general body and appearance of the finished product, the chemical tests
+upon which these depend should be made. Those especially important are
+the acid value, percentage unsaponifiable matter and titer test.
+
+A short description of the various oils and fats mentioned is sufficient
+for their use in the soap industry.
+
+_Tallow_ is the name given to the fat extracted from the solid fat or
+"suet" of cattle, sheep or horses. The quality varies greatly, depending
+upon the seasons of the year, the food and age of the animal and the
+method of rendering. It comes to the market under the distinction of
+edible and inedible, a further distinction being made in commerce as
+beef tallow, mutton tallow or horse tallow. The better quality is white
+and bleaches whiter upon exposure to air and light, though it usually
+has a yellowish tint, a well defined grain and a clean odor. It consists
+chiefly of stearin, palmitin and olein. Tallow is by far the most
+extensively used and important fat in the making of soap.
+
+In the manufacture of soaps for toilet purposes, it is usually necessary
+to produce as white a product as possible. In order to do this it often
+is necessary to bleach the tallow before saponification. The method
+usually employed is the Fuller's Earth process.
+
+
+FULLER'S EARTH PROCESS FOR BLEACHING TALLOW.
+
+From one to two tons of tallow are melted out into the bleaching tank.
+This tank is jacketed, made of iron and provided with a good agitator
+designed to stir up sediment or a coil provided with tangential downward
+opening perforations and a draw-off cock at the bottom. The coil is the
+far simpler arrangement, more cleanly and less likely to cause trouble.
+By this arrangement compressed air which is really essential in the
+utilization of the press (see later) is utilized for agitation. A dry
+steam coil in an ordinary tank may be employed in place of a jacketed
+tank, which lessens the cost of installation.
+
+The tallow in the bleaching tank is heated to 180° F. (82° C.) and ten
+pounds of dry salt per ton of fat used added and thoroughly mixed by
+agitation. This addition coagulates any albumen and dehydrates the fat.
+The whole mass is allowed to settle over night where possible, or for at
+least five hours. Any brine which has separated is drawn off from the
+bottom and the temperature of the fat is then raised to 160° F. (71° C).
+
+Five per cent. of the weight of the tallow operated upon, of dry
+Fuller's earth is now added and the whole mass agitated from twenty to
+thirty minutes.
+
+The new bleached fat, containing the Fuller's earth is pumped directly
+to a previously heated filter press and the issuing clear oil run
+directly to the soap kettle.
+
+One of the difficulties experienced in the process is the heating of the
+press to a temperature sufficient to prevent solidification of the fat
+without raising the press to too great a temperature. To overcome this
+the first plate is heated by wet steam. Air delivered from a blower and
+heated by passage through a series of coils raised to a high temperature
+by external application of heat (super-heated steam) is then substituted
+for the steam. The moisture produced by the condensation of the steam is
+vaporized by the hot air and carried on gradually to each succeeding
+plate where it again condenses and vaporizes. In this way the small
+quantity of water is carried through the entire press, raising its
+temperature to 80°-100° C. This temperature is subsequently maintained
+by the passage of hot air. By this method of heating the poor
+conductivity of hot air is overcome through the intermediary action of a
+liquid vapor and the latent heat of steam is utilized to obtain the
+initial rise in temperature. To heat a small press economically where
+conditions are such that a large output is not required the entire
+press may be encased in a small wooden house which can be heated by
+steam coils. The cake in the press is heated for some time after the
+filtration is complete to assist drainage. After such treatment the cake
+should contain approximately 15 per cent. fat and 25 per cent. water.
+The cake is now removed from the press and transferred to a small tank
+where it is treated with sufficient caustic soda to convert the fat
+content into soap.
+
+Saturated brine is then added to salt out the soap, the Fuller's earth
+is allowed to settle to the bottom of the tank and the soap which
+solidifies after a short time is skimmed off to be used in a cheap soap
+where color is not important. The liquor underneath may also be run off
+without disturbing the sediment to be used in graining a similar cheap
+soap. The waste Fuller's earth contains about 0.1 to 0.3 per cent. of
+fat.
+
+
+METHOD FOR FURTHER IMPROVEMENT OF COLOR.
+
+A further improvement of the color of the tallow may be obtained by
+freeing it from a portion of its free fatty acids, either with or
+without previous Fuller's earth bleaching.
+
+To carry out this process the melted fat is allowed to settle and as
+much water as possible taken off. The temperature is then raised to 160°
+F. with dry steam and enough saturated solution of soda ash added to
+remove 0.5 per cent. of the free fatty acids, while agitating the mass
+thoroughly mechanically or by air. The agitation is continued ten
+minutes, the whole allowed to settle for two hours and the foots drawn
+off. The soap thus formed entangles a large proportion of the impurities
+of the fat.
+
+
+VEGETABLE OILS.
+
+_Cocoanut Oil_, as the name implies, is obtained from the fruit of the
+cocoanut palm. This oil is a solid, white fat at ordinary temperature,
+having a bland taste and a characteristic odor. It is rarely
+adulterated and is very readily saponified. In recent years the price of
+this oil has increased materially because cocoanut oil is now being used
+extensively for edible purposes, especially in the making of
+oleomargarine. Present indications are that shortly very little high
+grade oil will be employed for soap manufacture since the demand for
+oleomargarine is constantly increasing and since new methods of refining
+the oil for this purpose are constantly being devised.
+
+The oil is found in the market under three different grades: (1) Cochin
+cocoanut oil, the choicest oil comes from Cochin (Malabar). This
+product, being more carefully cultivated and refined than the other
+grades, is whiter, cleaner and contains a smaller percentage of free
+acid. (2) Ceylon cocoanut oil, coming chiefly from Ceylon, is usually of
+a yellowish tint and more acrid in odor than Cochin oil. (3) Continental
+cocoanut oil (Copra, Freudenberg) is obtained from the dried kernels,
+the copra, which are shipped to Europe in large quantities, where the
+oil is extracted. These dried kernels yield 60 to 70 per cent oil. This
+product is generally superior to the Ceylon oil and may be used as a
+very satisfactory substitute for Cochin oil, in soap manufacture,
+provided it is low in free acid and of good color. The writer has
+employed it satisfactorily in the whitest and finest of toilet soaps
+without being able to distinguish any disadvantage to the Cochin oil.
+Since continental oil is usually cheaper than Cochin oil, it is
+advisable to use it, as occasion permits.
+
+Cocoanut oil is used extensively in toilet soap making, usually in
+connection with tallow. When used alone the soap made from this oil
+forms a lather, which comes up rapidly but which is fluffy and dries
+quickly. A pure tallow soap lathers very much slower but produces a more
+lasting lather. Thus the advantage of using cocoanut oil in soap is
+seen. It is further used in making a cocoanut oil soap by the cold
+process also for "fake" or filled soaps. The fatty acid content readily
+starts the saponification which takes place easily with a strong lye
+(25°-35° B.). Where large quantities of the oil are saponified care must
+be exercised as the soap formed suddenly rises or puffs up and may boil
+over. Cocoanut oil soap takes up large quantities of water, cases having
+been cited where a 500 per cent. yield has been obtained. This water of
+course dries out again upon exposure to the air. The soap is harsh to
+the skin, develops rancidity and darkens readily.
+
+_Palm Kernel Oil_, which is obtained from the kernels of the palm tree
+of West Africa, is used in soap making to replace cocoanut oil where the
+lower price warrants its use. It resembles cocoanut oil in respect to
+saponification and in forming a very similar soap. Kernel oil is white
+in color, has a pleasant nutty odor when fresh, but rapidly develops
+free acid, which runs to a high percentage.
+
+_Palm Oil_ is produced from the fruit of the several species of the palm
+tree on the western coast of Africa generally, but also in the
+Philippines. The fresh oil has a deep orange yellow tint not destroyed
+by saponification, a sweetish taste and an odor of orris root or violet
+which is also imparted to soap made from it. The methods by which the
+natives obtain the oil are crude and depend upon a fermentation, or
+putrefaction. Large quantities are said to be wasted because of this
+fact. The oil contains impurities in the form of fermentable fibre and
+albuminous matter, and consequently develops free fatty acid rapidly.
+Samples tested for free acid have been found to have hydrolized
+completely and one seldom obtains an oil with low acid content. Because
+of this high percentage of free fatty acid, the glycerine yield is
+small, though the neutral oil should produce approximately 12 per cent.
+glycerine. Some writers claim that glycerine exists in the free state
+in palm oil. The writer has washed large quantities of the oil and
+analyzed the wash water for glycerine. The results showed that the
+amount present did not merit its recovery. Most soap makers do not
+attempt to recover the glycerine from this oil, when used alone for soap
+manufacture.
+
+There are several grades of palm oil in commerce, but in toilet soap
+making it is advisable to utilize only Lagos palm oil, which is the best
+grade. Where it is desired to maintain the color of the soap this oil
+produces, a small quantity of the lower or "brass" grade of palm oil may
+be used, as the soap made from the better grades of oil gradually
+bleaches and loses its orange yellow color.
+
+Palm oil produces a crumbly soap which cannot readily be milled and is
+termed "short." When used with tallow and cocoanut oil, or 20 to 25 per
+cent. cocoanut oil, it produces a very satisfactory toilet soap. In the
+saponification of palm oil it is not advisable to combine it with tallow
+in the kettle, as the two do not readily mix.
+
+Since the finished soap has conveyed to it the orange color of the oil,
+the oil is bleached before saponification. Oxidation readily destroys
+the coloring matter, while heat and light assist materially. The methods
+generally employed are by the use of oxygen developed by bichromates and
+hydrochloric acid and the direct bleaching through the agency of the
+oxygen of the air.
+
+
+CHROME BLEACHING OF PALM OIL.
+
+The chrome process of bleaching palm oil is more rapid and the oxygen
+thus derived being more active will bleach oils which air alone cannot.
+It depends upon the reaction:
+
+    Na_{2}Cr_{2}O_{7} + 8HCl = Cr_{2}Cl_{6} + 2NaCl + 7O.
+
+in which the oxygen is the active principle. In practice it is found
+necessary to use an excess of acid over that theoretically indicated.
+
+For the best results an oil should be chosen containing under 2 per
+cent. impurities and a low percentage of free fatty acids. Lagos oil is
+best adapted to these requirements. The oil is melted by open steam from
+a jet introduced through the bung, the melted oil and condensed water
+running to the store tank through two sieves (about 1/8 inch mesh) to
+remove the fibrous material and gross impurities. The oil thus obtained
+contains fine earthy and fibrous material and vegetable albuminous
+matter which should be removed, as far as possible, since chemicals are
+wasted in their oxidation and they retard the bleaching. This is best
+done by boiling the oil for one hour with wet steam and 10 per cent.
+solution of common salt (2 per cent. dry salt on weight of oil used) in
+a lead-lined or wooden tank. After settling over night the brine and
+impurities are removed by running from a cock at the bottom of the vat
+and the oil is run out into the bleaching tank through an oil cock,
+situated about seven inches from the bottom.
+
+The bleaching tank is a lead-lined iron tank of the approximate
+dimensions of 4 feet deep, 4 feet long and 3-1/2 feet wide, holding
+about 1-1/2 tons. The charge is one ton. A leaden outlet pipe is fixed
+at the bottom, to which is attached a rubber tube closed by a screw
+clip. A plug also is fitted into the lead outlet pipe from above. Seven
+inches above the lower outlet is affixed another tap through which the
+oil is drawn off.
+
+The tank is further equipped with a wet steam coil and a coil arranged
+to allow thorough air agitation, both coils being of lead. A good
+arrangement is to use one coil to deliver either air or steam. These
+coils should extend as nearly as possible over the entire bottom of the
+tank and have a number of small downward perforations, so as to spread
+the agitation throughout the mass.
+
+The temperature of the oil is reduced by passing in air to 110° F. and
+40 pounds of fine common salt per ton added through a sieve. About
+one-half of the acid (40 pounds of concentrated commercial hydrochloric
+acid) is now poured in and this is followed by the sodium bichromate in
+concentrated solution, previously prepared in a small lead vat or
+earthen vessel by dissolving 17 pounds of bichromate in 45 pounds
+commercial hydrochloric acid. This solution should be added slowly and
+should occupy three hours, the whole mass being thoroughly agitated with
+air during the addition and for one hour after the last of the bleaching
+mixture has been introduced. The whole mixture is now allowed to settle
+for one hour and the exhausted chrome liquors are then run off from the
+lower pipe to a waste tank. About 40 gallons of water are now run into
+the bleached oil and the temperature raised by open steam to 150° to
+160° F. The mass is then allowed to settle over night.
+
+One such wash is sufficient to remove the spent chrome liquor
+completely, provided ample time is allowed for settling. A number of
+washings given successively with short periods of settling do not remove
+the chrome liquors effectually. The success of the operation depends
+entirely upon the completeness of settling.
+
+The wash water is drawn off as before and the clear oil run to storage
+tanks or to the soap kettle through the upper oil cock.
+
+The waste liquors are boiled with wet steam and the oil skimmed from the
+surface, after which the liquors are run out through an oil trap.
+
+By following the above instructions carefully it is possible to bleach
+one ton of palm oil with 17 pounds of bichromate of soda and 85 pounds
+hydrochloric acid.
+
+The spent liquors should be a bright green color. Should they be of a
+yellow or brownish shade insufficient acid has been allowed and more
+must be added to render the whole of the oxygen available.
+
+If low grade oils are being treated more chrome will be necessary, the
+amount being best judged by conducting the operation as usual and after
+the addition of the bichromate, removing a sample of the oil, washing
+the sample and noting the color of a rapidly cooled sample.
+
+A little practice will enable the operator to judge the correspondence
+between the color to be removed and the amount of bleaching mixture to
+be added.
+
+To obtain success with this process the method of working given must be
+adhered to even in the _smallest detail_. This applies to the
+temperature at which each operation is carried out particularly.
+
+
+AIR BLEACHING OF PALM OIL.
+
+The method of conducting this process is identical with the chrome
+process to the point where the hydrochloric acid is to be added to the
+oil. In this method no acid or chrome is necessary, as the active
+bleaching agent is the oxygen of the air.
+
+The equipment is similar to that of the former process, except that a
+wooden tank in which no iron is exposed will suffice to bleach the oil
+in. The process depends in rapidity upon the amount of air blown through
+the oil and its even distribution. Iron should not be present or exposed
+to the oil during bleaching, as it retards the process considerably.
+
+After the impurities have been removed, as outlined under the chrome
+process, the temperature of the oil is raised by open steam to boiling.
+The steam is then shut off and air allowed to blow through the oil until
+it is completely bleached, the temperature being maintained above 150°
+F. by occasionally passing in steam. Usually a ton of oil is readily and
+completely bleached after the air has been passed through it for 18 to
+20 hours, provided the oil is thoroughly agitated by a sufficient flow
+of air.
+
+If the oil has been allowed to settle over night, it is advisable to run
+off the condensed water and impurities by the lower cock before
+agitating again the second day.
+
+When the oil has been bleached to the desired color, which can be
+determined by removing a sample and cooling, the mass is allowed to
+settle, the water run off to a waste tank from which any oil carried
+along may be skimmed off and the supernatant clear oil run to the
+storage or soap kettle.
+
+In bleaching by this process, while the process consumes more time and
+is not as efficient in bleaching the lower grade oils, the cost of
+bleaching is less and with a good oil success is more probable, as there
+is no possibility of any of the chrome liquors being present in the oil.
+These give the bleached oil a green tint when the chrome method is
+improperly conducted and they are not removed.
+
+Instead of blowing the air through it, the heater oil may be brought
+into contact with the air, either by a paddle wheel arrangement, which,
+in constantly turning, brings the oil into contact with the air, or by
+pumping the heated oil into an elevated vessel, pierced with numerous
+fine holes from which the oil continuously flows back into the vessel
+from which the oil is pumped. While in these methods air, light and heat
+act simultaneously in the bleaching of the oil, the equipment required
+is too cumbersome to be practical.
+
+Recent investigations[1] in bleaching palm oil by oxygen have shown that
+not only the coloring matter but the oil itself was affected. In
+bleaching palm oil for 30 hours with air the free fatty acid content
+rose and titer decreased considerably.
+
+_Olive Oil_, which comes from the fruit of the olive trees, varies
+greatly in quality, according to the method by which it is obtained and
+according to the tree bearing the fruit. Three hundred varieties are
+known in Italy alone. Since the larger portion of olive oil is used for
+edible purposes, a lower grade, denatured oil, denatured because of the
+tariff, is used for soap manufacture in this country. The oil varies in
+color from pale green to golden yellow. The percentage of free acid in
+this oil varies greatly, though the oil does not turn rancid easily. It
+is used mainly in the manufacture of white castile soap.
+
+Olive oil foots, which is the oil extracted by solvents after the better
+oil is expressed, finds its use in soap making mostly in textile soaps
+for washing and dyeing silks and in the production of green castile
+soaps.
+
+Other oils, as poppy seed oil, sesame oil, cottonseed oil, rape oil,
+peanut (arachis) oil, are used as adulterants for olive oil, also as
+substitutes in the manufacture of castile soap, since they are cheaper
+than olive oil.
+
+_Cottonseed Oil_ is largely used in the manufacture of floating and
+laundry soaps. It may be used for toilet soaps where a white color is
+not desired, as yellow spots appear on a finished soap in which it has
+been used after having been in stock a short time.
+
+_Corn Oil and Soya Bean Oil_ are also used to a slight extent in the
+manufacture of toilet soaps, although the oils form a soap of very
+little body. Their soaps also spot yellow on aging.
+
+Corn oil finds its greatest use in the manufacture of soap for washing
+automobiles. It is further employed for the manufacture of cheap liquid
+soaps.
+
+_Fatty Acids_ are also used extensively in soap manufacture. While the
+soap manufacturer prefers to use a neutral oil or fat, since from these
+the by-product glycerine is obtained, circumstances arise where it is
+an advantage to use the free fatty acids. Red oil (oleic acid, elaine)
+and stearic acid are the two fatty acids most generally bought for soap
+making. In plants using the Twitchell process, which consists in
+splitting the neutral fats and oils into fatty acids and glycerine by
+dilute sulphuric acid and producing their final separation by the use of
+so-called aromatic sulphonic acids, these fatty acids consisting of a
+mixture of oleic, stearic, palmitic acids, etc., are used directly after
+having been purified by distillation, the glycerine being obtained from
+evaporating the wash water.
+
+Oleic acid (red oil) and stearic acid are obtained usually by the
+saponification of oils, fats and greases by acid, lime or water under
+pressure or Twitchelling. The fatty acids thus are freed from their
+combination with glycerine and solidify upon cooling, after which they
+are separated from the water and pressed at a higher or lower
+temperature. The oleic acid, being liquid at ordinary temperature,
+together with some stearic and palmitic acid, is thus pressed out. These
+latter acids are usually separated by distillation, combined with the
+press cake further purified and sold as stearic acid.
+
+The red oil, sometimes called saponified red oil, is often semi-solid,
+resembling a soft tallow, due to the presence of stearic acid. The
+distilled oils are usually clear, varying in color from light to a deep
+brown. Stearic acid, which reaches the trade in slab form, varies in
+quality from a soft brown, greasy, crumbly solid of unpleasant odor to a
+snow white, wax-like, hard, odorless mass. The quality of stearic acid
+is best judged by the melting point, since the presence of any oleic
+acid lowers this. The melting point of the varieties used in soap
+manufacture usually ranges from 128° to 132° F. Red oil is used in the
+manufacture of textile soaps, replacing olive oil foots soap for this
+purpose, chlorophyll being used to color the soap green. Stearic acid,
+being the hard firm fatty acid, may be used in small quantities to give
+a better grade of soap body and finish. In adding this substance it
+should always be done in the crutcher, as it will not mix in the kettle.
+It finds its largest use for soap, however, in the manufacture of
+shaving soaps and shaving creams, since it produces the non-drying
+creamy lather so greatly desired for this purpose. Both red oil and
+stearic acid being fatty acids, readily unite with the alkali
+carbonates, carbon dioxide being formed in the reaction and this method
+is extensively used in the formation of soap from them.
+
+
+RANCIDITY OF OILS AND FATS.
+
+Rancidity in neutral oils and fats is one of the problems the soap
+manufacturer has to contend with. The mere saying that an oil is rancid
+is no indication of its being high in free acid. The two terms rancidity
+and acidity are usually allied. Formerly, the acidity of a fat was
+looked upon as the direct measure of its rancidity. This idea is still
+prevalent in practice and cannot be too often stated as incorrect. Fats
+and oils may be _acid_, or _rancid_, or _acid and rancid_. In an acid
+fat there has been a hydrolysis of the fat and it has developed a rather
+high percentage of free acid. A rancid fat is one in which have been
+developed compounds of an odoriferous nature. An acid and rancid fat is
+one in which both free acid and organic compounds of the well known
+disagreeable odors have been produced.
+
+It cannot be definitely stated just how this rancidity takes place, any
+more than just what are the chemical products causing rancidity. The
+only conclusion that one may draw is that the fats are first hydrolyzed
+or split up into glycerine and free fatty acids. This is followed by an
+oxidation of the products thus formed.
+
+Moisture, air, light, enzymes (organized ferments) and bacteria are all
+given as causes of rancidity.
+
+It seems very probable that the initial splitting of the fats is caused
+by enzymes, which are present in the seeds and fruits of the vegetable
+oils and tissue of animal fats, in the presence of moisture. Lewkowitsch
+strongly emphasizes this point and he is substantiated in his idea by
+other authorities. Others hold that bacteria or micro-organisms are the
+cause of this hydrolysis, citing the fact that they have isolated
+various micro-organisms from various fats and oils. The acceptance of
+the bacterial action would explain the various methods of preservation
+of oils and fats by the use of antiseptic preparations. It cannot,
+however, be accepted as a certainty that bacteria cause the rancidity of
+fats.
+
+The action of enzymes is a more probable explanation.
+
+The hydrolysis of fats and oils is accelerated when they are allowed to
+remain for some time in the presence of organic non-fats. Thus, palm
+oil, lower grades of olive oil, and tallow, which has been in contact
+with the animal tissue for a long time, all contain other nitrogenous
+matter and exhibit a larger percentage of free fatty acid than the oils
+and fats not containing such impurities.
+
+Granting this initial splitting of the fat into free fatty acids and
+glycerine, this is not a sufficient explanation. The products thus
+formed must be acted upon by air and light. It is by the action of these
+agents that there is a further action upon the products, and from this
+oxidation we ascertain by taste and smell (chemical means are still
+unable to define rancidity) whether or not a fat is rancid. While some
+authorities have presumed to isolate some of these products causing
+rancidity, we can only assume the presence of the various possible
+compounds produced by the action of air and light which include oxy
+fatty acids, lactones, alcohols, esters, aldehydes and other products.
+
+The soap manufacturer is interested in rancidity to the extent of the
+effect upon the finished soap. Rancid fats form darker soaps than fats
+in the neutral state, and very often carry with them the disagreeable
+odor of a rancid oil. Further, a rancid fat or oil is usually high in
+free acid. It is by no means true, however, that rancidity is a measure
+for acidity, for as has already been pointed out, an oil may be rancid
+and not high in free acid.
+
+The percentage of free fatty acid is of even greater importance in the
+soap industry. The amount of glycerine yield is dependent upon the
+percentage of free fatty acid and is one of the criterions of a good fat
+or oil for soap stock.
+
+
+PREVENTION OF RANCIDITY.
+
+Since moisture, air, light and enzymes, produced by the presence of
+organic impurities, are necessary for the rancidity of a fat or oil, the
+methods of preventing rancidity are given. Complete dryness, complete
+purification of fats and oils and storage without access of air or light
+are desirable. Simple as these means may seem, they can only be
+approximated in practice. The most difficult problem is the removal of
+the last trace of moisture. Impurities may be lessened very often by the
+use of greater care. In storing it is well to store in closed barrels or
+closed iron tanks away from light, as it has been observed that oils and
+fats in closed receptacles become rancid less rapidly than those in open
+ones, even though this method of storing is only partially attained.
+Preservatives are also used, but only in edible products, where their
+effectiveness is an open question.
+
+
+CHEMICAL CONSTANTS OF OILS AND FATS.
+
+Besides the various physical properties of oils and fats, such as
+color, specific gravity, melting point, solubility, etc., they may be
+distinguished chemically by a number of chemical constants. These are
+the iodine number, the acetyl value, saponification number,
+Reichert-Meissl number for volatile acids, Hehner number for insoluble
+acids. These constants, while they vary somewhat with any particular oil
+or fat, are more applicable to the edible products and are criterions
+where any adulteration of fat or oil is suspected. The methods of
+carrying out the analyses of oils and fats to obtain these constants are
+given in the various texts[2] on oils and fats, and inasmuch as they are
+not of great importance to the soap industry they are merely mentioned
+here.
+
+
+OIL HARDENING OR HYDROGENATING.
+
+It is very well known that oils and fats vary in consistency and
+hardness, depending upon the glycerides forming same. Olein, a
+combination of oleic acid and glycerine, as well as oleic acid itself
+largely forms the liquid portion of oils and fats. Oleic acid
+(C_{18}H_{34}O_{2}) is an unsaturated acid and differs from stearic acid
+(C_{18}H_{36}O_{2}), the acid forming the hard firm portion of oils and
+fats, by containing two atoms of hydrogen less in the molecule.
+Theoretically it should be a simple matter to introduce two atoms of
+hydrogen into oleic acid or olein, and by this mere addition convert
+liquid oleic acid and olein into solid stearic acid and stearine.
+
+For years this was attempted and all attempts to apply the well known
+methods of reduction (addition of hydrogen) in organic chemistry, such
+as treatment with tin and acid, sodium amalgam, etc., were unsuccessful.
+In recent years, however, it has been discovered that in the presence of
+a catalyzer, nickel in finely divided form or the oxides of nickel are
+usually employed, the process of hydrogenating an oil is readily
+attained upon a practical basis.
+
+The introduction of hardened oils has opened a new source of raw
+material for the soap manufacturer in that it is now possible to use
+oils in soap making which were formerly discarded because of their
+undesirable odors. Thus fish or train oils which had up to the time of
+oil hydrogenating resisted all attempts of being permanently deodorized,
+can now be employed very satisfactorily for soap manufacture. A Japanese
+chemist, Tsujimoto[3] has shown that fish oils contain an unsaturated
+acid of the composition C_{18}H_{28}O_{2}, for which he proposed the
+name clupanodonic acid. By the catalytic hardening of train oils this
+acid passes to stearic acid and the problem of deodorizing these oils is
+solved.[4]
+
+At first the introduction of hardened oils for soap manufacture met with
+numerous objections, due to the continual failures of obtaining a
+satisfactory product by the use of same. Various attempts have now shown
+that these oils, particularly hardened train oils, produce
+extraordinarily useful materials for soap making. These replace
+expensive tallow and other high melting oils. It is of course impossible
+to employ hardened oils alone, as a soap so hard would thus be obtained
+that it would be difficultly soluble in water and possess very little
+lathering quality. By the addition of 20-25% of tallow oil or some other
+oil forming a soft soap a very suitable soap for household use may be
+obtained. Ribot[5] discusses this matter fully. Hardened oils readily
+saponify, may be perfumed without any objections and do not impart any
+fishy odor to an article washed with same. Meyerheim[6] states that
+through the use of hydrogenated oils the hardness of soap is
+extraordinarily raised, so that soap made from hardened cottonseed oil
+is twelve times as hard as the soap made from ordinary cottonseed oil.
+This soap is also said to no longer spot yellow upon aging, and as a
+consequence of its hardness, is able to contain a considerably higher
+content of rosin through which lathering power and odor may be improved.
+Hardened oils can easily be used for toilet soap bases, provided they
+are not added in too great a percentage.
+
+The use of hardened oils is not yet general, but there is little doubt
+that the introduction of this process goes a long way toward solving the
+problem of cheaper soap material for the soap making industry.
+
+
+GREASE.
+
+Grease varies so greatly in composition and consistency that it can
+hardly be classed as a distinctive oil or fat. It is obtained from
+refuse, bones, hides, etc., and while it contains the same constituents
+as tallow, the olein content is considerably greater, which causes it to
+be more liquid in composition. Grease differs in color from an off-white
+to a dark brown. The better qualities are employed in the manufacture of
+laundry and chip soap, while the poorer qualities are only fit for the
+cheapest of soaps used in scrubbing floors and such purposes. There is
+usually found in grease a considerable amount of gluey matter, lime and
+water. The percentage of free fatty acid is generally high.
+
+The darker grades of grease are bleached before being used. This is done
+by adding a small quantity of sodium nitrate to the melted grease and
+agitating, then removing the excess saltpeter by decomposing with
+sulphuric acid. A better method of refining, however, is by
+distillation. The chrome bleach is also applicable.
+
+
+ROSIN (COLOPHONY, YELLOW ROSIN, RESINA).
+
+Rosin is the residue which remains after the distillation of turpentine
+from the various species of pines. The chief source of supply is in the
+States of Georgia North and South Carolina. It is a transparent, amber
+colored hard pulverizable resin. The better grades are light in color
+and known as water white (w. w.) and window glass (w. g.). These are
+obtained from a tree which has been tapped for the first year. As the
+same trees are tapped from year to year, the product becomes deeper and
+darker in color until it becomes almost black.
+
+The constituents of rosin are chiefly (80-90%) abietic acid or its
+anhydride together with pinic and sylvic acids. Its specific gravity is
+1.07-1.08, melting point about 152.5 C., and it is soluble in alcohol,
+ether, benzine, carbon disulfide, oils, alkalis and acetic acid. The
+main use of rosin, outside of the production of varnishes, is in the
+production of laundry soaps, although a slight percentage acts as a
+binder and fixative for perfumes in toilet soaps and adds to their
+detergent properties. Since it is mainly composed of acids, it readily
+unites with alkaline carbonates, though the saponification is not quite
+complete and the last portion must be completed through the use of
+caustic hydrates, unless an excess of 10% carbonate over the theoretical
+amount is used. A lye of 20° B. is best adapted to the saponification of
+rosin when caustic hydrates are employed for this purpose, since weak
+lyes cause frothing. While it is sometimes considered that rosin is an
+adulterant for soap, this is hardly justifiable, as it adds to the
+cleansing properties of soap. Soaps containing rosin are of the well
+known yellowish color common to ordinary laundry soaps. The price of
+rosin has so risen in the last few years that it presents a problem of
+cost to the soap manufacturer considering the price at which laundry
+soaps are sold.
+
+
+ROSIN SAPONIFICATION.
+
+As has been stated, rosin may be saponified by the use of alkaline
+carbonates. On account of the possibility of the soap frothing over, the
+kettle in which the operation takes place should be set flush with the
+floor, which ought to be constructed of cement. The kettle itself is an
+open one with round bottom, equipped with an open steam coil and skimmer
+pipe, and the open portion is protected by a semi-circular rail. A
+powerful grid, having a 3-inch mesh, covers one-half of the kettle, the
+sharp edges protruding upwards.
+
+The staves from the rosin casks are removed at the edge of the kettle,
+the rosin placed on the grid and beaten through with a hammer to break
+it up into small pieces.
+
+To saponify a ton of rosin there are required 200 lbs. soda ash, 1,600
+lbs. water and 100 lbs. salt. Half the water is run into the kettle,
+boiled, and then the soda ash and half the salt added. The rosin is now
+added through the grid and the mixture thoroughly boiled. As carbon
+dioxide is evolved by the reaction the boiling is continued for one hour
+to remove any excess of this gas. A portion of the salt is gradually
+added to grain the soap well and to keep the mass in such condition as
+to favor the evolution of gas. The remainder of the water is added to
+close the soap and boiling continued for one or two hours longer. At
+this point the kettle must be carefully watched or it will boil over
+through the further escape of carbon dioxide being hindered. The mass,
+being in a frothy condition, will rapidly settle by controlling the flow
+of steam. The remaining salt is then scattered in and the soap allowed
+to settle for two hours or longer. The lyes are then drained off the
+top. If the rosin soap is required for toilet soaps, it is grained a
+second time. The soap is now boiled with the water caused by the
+condensation of the steam, which changes it to a half grained soap
+suitable for pumping. A soap thus made contains free soda ash 0.15% or
+less, free rosin about 15%. The mass is then pumped to the kettle
+containing the soap to which it is to be added at the proper stage. The
+time consumed in thus saponifying rosin is about five hours.
+
+
+NAPHTHENIC ACIDS.
+
+The naphtha or crude petroleum of the various provinces in Europe, as
+Russia, Galacia, Alsace and Roumania yield a series of bodies of acid
+character upon refining which are designated under the general name of
+naphthenic acids. These acids are retained in solution in the alkaline
+lyes during the distillation of the naphtha in the form of alkaline
+naphthenates. Upon adding dilute sulphuric acid to these lyes the
+naphthenates are decomposed and the naphthenic acids float to the
+surface in an oily layer of characteristic disagreeable odor and varying
+from yellow to brown in color[7]. In Russia particularly large
+quantities of these acids are employed in the manufacture of soap.
+
+The soaps formed from naphthenic acids have recently been
+investigated[8] and found to resemble the soaps made from cocoanut oil
+and palm kernel oil, in that they are difficult to salt out and
+dissociate very slightly with water. The latter property makes them
+valuable in textile industries when a mild soap is required as a
+detergent, e. g., in the silk industry. These soaps also possess a high
+solvent power for mineral oils and emulsify very readily. The mean
+molecular weight of naphthenic acids themselves is very near that of the
+fatty acids contained in cocoanut oil, and like those of cocoanut oil a
+portion of the separated acids are volatile with steam. The iodine
+number indicates a small content of unsaturated acids.
+
+That naphthenic acids are a valuable soap material is now recognized,
+but except in Russia the soap is not manufactured to any extent at the
+present time.
+
+
+ALKALIS.
+
+The common alkali metals which enter into the formation of soap are
+sodium and potassium. The hydroxides of these metals are usually used,
+except in the so called carbonate saponification of free fatty acids in
+which case sodium and potassium carbonate are used. A water solution of
+the caustic alkalis is known as lye, and it is as lyes of various
+strengths that they are added to oils and fats to form soap. The density
+or weight of a lye is considerably greater than that of water, depending
+upon the amount of alkali dissolved, and its weight is usually
+determined by a hydrometer. This instrument is graduated by a
+standardized scale, and while all hydrometers should read alike in a
+liquid of known specific gravity, this is generally not the case, so
+that it is advisable to check a new hydrometer for accurate work against
+one of known accuracy. In this country the Baumé scale has been adopted,
+while in England a different graduation known as the Twaddle scale is
+used. The strength of a lye or any solution is determined by the
+distance the instrument sinks into the solution, and we speak of the
+strength of a solution as so many degrees Baumé or Twaddle which are
+read to the point where the meniscus of the lye comes on the graduated
+scale. Hydrometers are graduated differently for liquids of different
+weights. In the testing of lyes one which is graduated from 0° to 50° B.
+is usually employed.
+
+_Caustic soda_ is received by the consumer in iron drums weighing
+approximately 700 lbs. each. The various grades are designated as 60,
+70, 74, 76 and 77%. These percentages refer to the percentage of sodium
+oxide (Na_{2}O) in 100 parts of pure caustic soda formed by the
+combination of 77-1/2 parts of sodium oxide and 22-1/2 parts of water,
+77-1/2% being chemically pure caustic soda. There are generally
+impurities present in commercial caustic soda. These consist of sodium
+carbonate, sodium chloride or common salt and sometimes lime. It is
+manufactured by treating sodium carbonate in an iron vessel with calcium
+hydroxide or slaked lime, or by electrolysis of common salt. The latter
+process has yet been unable to compete with the former in price.
+Formerly all the caustic soda used in soap making was imported, and it
+was only through the American manufacturer using a similar container to
+that used by foreign manufacturers that they were able to introduce
+their product. This prejudice has now been entirely overcome and most of
+the caustic soda used in this country is manufactured here.
+
+
+CAUSTIC POTASH.
+
+The output of the salts containing potassium is controlled almost
+entirely by Germany. Formerly the chief source of supply of potassium
+compounds was from the burned ashes of plants, but about fifty years ago
+the inexhaustible salt mines of Stassfurt, Germany, were discovered.
+The salt there mined contains, besides the chlorides and sulphates of
+sodium, magnesium, calcium and other salts, considerable quantities of
+potassium chloride, and the Stassfurt mines at present are practically
+the entire source of all potassium compounds, in spite of the fact that
+other localities have been sought to produce these compounds on a
+commercial basis, especially by the United States government.
+
+After separating the potassium chloride from the magnesium chloride and
+other substances found in Stassfurt salts the methods of manufacture of
+caustic potash are identical to those of caustic soda. In this case,
+however, domestic electrolytic caustic potash may be purchased cheaper
+than the imported product and it gives results equal to those obtained
+by the use of the imported article, opinions to the contrary among soap
+makers being many. Most of the caustic potash in the United States is
+manufactured at Niagara Falls by the Niagara Alkali Co., and the Hooker
+Electrochemical Co., chlorine being obtained as a by-product. The latter
+concern employs the Townsend Cell, for the manufacture of electrolytic
+potash, and are said to have a capacity for making 64 tons of alkali
+daily.
+
+Since the molecular weight of caustic potash (56) is greater than that
+of caustic soda (40) more potash is required to saponify a pound of fat.
+The resulting potash soap is correspondingly heavier than a soda soap.
+When salt is added to a potassium soap double decomposition occurs, the
+potassium soap being transformed to a sodium soap and the potassium
+uniting with the chlorine to form potassium chloride. This was one of
+the earliest methods of making a hard soap, especially in Germany, where
+potash was derived from leeching ashes of burned wood and plants.
+
+
+SODIUM CARBONATE (SODA ASH).
+
+While carbonate of soda is widely distributed in nature the source of
+supply is entirely dependent upon the manufactured product. Its uses are
+many, but it is especially important to the soap industry in the so
+called carbonate saponification of free fatty acids, as a constituent of
+soap powders, in the neutralization of glycerine lyes and as a filler
+for laundry soaps.
+
+The old French Le Blanc soda process, which consists in treating common
+salt with sulphuric acid and reducing the sodium sulphate (salt cake)
+thus formed with carbon in the form of charcoal or coke to sodium
+sulphide, which when treated with calcium carbonate yields a mixture of
+calcium sulphide and sodium carbonate (black ash) from which the
+carbonate is dissolved by water, has been replaced by the more recent
+Solvay ammonia soda process. Even though there is a considerable loss of
+salt and the by-product calcium chloride produced by this process is
+only partially used up as a drying agent, and for refrigerating
+purposes, the Le Blanc process cannot compete with the Solvay process,
+so that the time is not far distant when the former will be considered a
+chemical curiosity. In the Solvay method of manufacture sodium chloride
+(common salt) and ammonium bicarbonate are mixed in solution. Double
+decomposition occurs with the formation of ammonium chloride and sodium
+bicarbonate. The latter salt is comparatively difficultly soluble in
+water and crystallizes out, the ammonium chloride remaining in solution.
+When the sodium bicarbonate is heated it yields sodium carbonate, carbon
+dioxide and water; the carbon dioxide is passed into ammonia which is
+set free from the ammonium chloride obtained as above by treatment with
+lime (calcium oxide) calcium chloride being the by-product.
+
+Sal soda or washing soda is obtained by recrystallizing a solution of
+soda ash in water. Large crystals of sal soda containing but 37% sodium
+carbonate are formed.
+
+
+POTASSIUM CARBONATE.
+
+Potassium carbonate is not extensively used in the manufacture of soap.
+It may be used in the forming of soft soaps by uniting it with free
+fatty acids. The methods of manufacture are the same as for sodium
+carbonate, although a much larger quantity of potassium carbonate than
+carbonate of soda is obtained from burned plant ashes. Purified
+potassium carbonate is known as _pearl ash_.
+
+
+ADDITIONAL MATERIAL USED IN SOAP MAKING.
+
+Water is indispensable to the soap manufacturer. In the soap factory
+_hard_ water is often the cause of much trouble. Water, which is the
+best solvent known, in passing through the crevices of rocks dissolves
+some of the constituents of these, and the water is known as hard. This
+hardness is of two kinds, _temporary_ and _permanent_. Temporarily hard
+water is formed by water, which contains carbonic acid, dissolving a
+portion of calcium carbonate or carbonate of lime. Upon boiling, the
+carbonic acid is driven from the water and the carbonate, being
+insoluble in carbon dioxide free water, is deposited. This is the cause
+of boiler scale, and to check this a small amount of sal ammoniac may be
+added to the water, which converts the carbonate into soluble calcium
+chloride and volatile ammonium carbonate. Permanent hardness is caused
+by calcium sulphate which is soluble in 400 parts of water and cannot be
+removed by boiling.
+
+The presence of these salts in water form insoluble lime soaps which act
+as inert bodies as far as their value for the common use of soap is
+concerned. Where the percentage of lime in water is large this should be
+removed. A method generally used is to add about 5% of 20° B. sodium
+silicate to the hard water. This precipitates the lime and the water is
+then sufficiently pure to use.
+
+_Salt_, known as sodium chloride, is used to a large extent in soap
+making for "salting out" the soap during saponification, as well as
+graining soaps. Soap ordinarily soluble in water is insoluble in a salt
+solution, use of which is made by adding salt to the soap which goes
+into solution and throws any soap dissolved in the lyes out of solution.
+Salt may contain magnesium and calcium chlorides, which of course are
+undesirable in large amounts. The products on the market, however, are
+satisfactory, thus no detail is necessary.
+
+_Filling materials_ used are sodium silicate, or water glass, talc,
+silex, pumice, starch, borax, tripoli, etc.
+
+Besides these other materials are used in the refining of the oils and
+fats, and glycerine recovery, such as Fuller's earth, bichromates of
+soda or potash, sulphate of alumina, sulphuric and hydrochloric acids
+and alcohol.
+
+A lengthy description of these substances is not given, as their modes
+of use are detailed elsewhere.
+
+FOOTNOTES:
+
+[1] Seifensieder Zeit, 1913, 40, p. 687, 724, 740.
+
+[2] Official Methods, see Bull. 107, A. O. A. C., U. S. Dept. Agricult.
+
+[3] Journ. Coll. of Engin. Tokyo Imper. Univ. (1906), p. 1. Abs. Chem.
+Revue f. d. Fett-u. Harz, Ind. 16, p. 84; 20, p. 8.
+
+[4] Meyerheim--Fort. der Chem., Physik. und Physik. Chem. (1913), 8. 6,
+p. 293-307.
+
+[5] Seifs. Ztg. (1913), 40, p. 142.
+
+[6] Loc. cit.
+
+[7] Les Matieres Graisses (1914), 7, 69, p. 3367.
+
+[8] Zeit. f. Angew. Chem. (1914), 27, 1, p. 2-4.
+
+
+
+
+CHAPTER II
+
+Construction and Equipment of a Soap Plant.
+
+
+No fixed plan for the construction and equipment of a soap plant can be
+given. The specifications for a soap factory to be erected or remodeled
+must suit the particular cases. Very often a building which was
+constructed for a purpose other than soap manufacture must be adapted
+for the production of soap. In either case it is a question of
+engineering and architecture, together with the knowledge obtained in
+practice and the final decision as to the arrangement is best solved by
+a conference with those skilled in each of these branches.
+
+An ideal soap plant is one in which the process of soap making, from the
+melting out of the stock to the packing and shipping of the finished
+product, moves downward from floor to floor, since by this method it is
+possible to utilize gravitation rather than pumping liquid fats and
+fluid soaps. Convenience and economy are obtained by such an
+arrangement.
+
+The various machinery and other equipment for soap manufacture are well
+known to those connected with this industry. It varies, of course,
+depending upon the kind of soap to be manufactured, and full
+descriptions of the necessary machinery are best given in the catalogs
+issued by the manufacturers of such equipment, who in this country are
+most reliable.
+
+To know just what equipment is necessary can very easily be described by
+a brief outline of the process various soaps undergo to produce the
+finished article. After the saponification has taken place in the _soap
+kettle_ the molten soap is run directly into the soap _frames_, which
+consist of an oblong compartment, holding anywhere from 400 to 1,200
+pounds, with removable steel sides and mounted upon trucks, in which it
+solidifies. In most cases it is advisable to first run the soap into a
+_crutcher_ or mixer which produces a more homogeneous mass than if this
+operation is omitted. Color and perfume may also be added at this point,
+although when a better grade of perfume is added it must be remembered
+that there is considerable loss due to volatilization of same. When a
+_drying machine_ is employed the molten soap is run directly upon the
+rollers of this machine, later adding about 1.0% zinc oxide to the soap
+from which it passes continuously through the drying chamber and is
+emitted in chip form ready for milling. After the soap has been framed,
+it is allowed to cool and solidify, which takes several days, and then
+the sides of the frame are stripped off. The large solid cake is cut
+with wires by hand or by a _slabber_ into slabs of any desired size.
+These slabs are further divided into smaller divisions by the _cutting
+table_. In non-milled soaps (laundry soaps, floating soaps, etc.), these
+are pressed at this stage, usually by automatic presses, after a thin
+hard film has been formed over the cake by allowing it to dry slightly.
+In making these soaps they are not touched by hand at any time during
+the operation, the pressing, wrapping and packing all being done by
+machinery. For a milled soap the large slabs are cut into narrow oblong
+shapes by means of the cutting table to readily pass into the feeder of
+the _chipper_, the chips being spread upon _trays_ and dried in a _dry
+house_ until the moisture content is approximately 15%.
+
+The process of milling is accomplished by passing the dried soap chips
+through a _soap mill_, which is a machine consisting of usually three or
+four contiguous, smooth, granite rollers operated by a system of gears
+and set far enough apart to allow the soap to pass from a hopper to the
+first roller, from which it is constantly conveyed to each succeeding
+roller as a thin film, and finally scraped from the last roller to fall
+into the _milling box_ in thin ribbon form. These mills are often
+operated in tandem, which necessitates less handling of soap by the
+operator. The object of milling is to give the soap a glossy, smooth
+finish and to blend it into a homogeneous mass. The perfume, color,
+medication or any other material desired are added to the dried soap
+chips prior to milling. Some manufacturers use an _amalgamator_ to
+distribute these uniformly through the soap, which eliminates at least
+one milling. When a white soap is being put through the mill, it is
+advisable to add from 0.5% to 1% of a good, fine quality of zinc oxide
+to the soap, if this substance has not been previously added. This
+serves to remove the yellowish cast and any translucency occasioned by
+plodding. Too great a quantity of this compound added, later exhibits
+itself by imparting to the soap a dead white appearance. Inasmuch as the
+milling process is one upon which the appearance of a finished cake of
+toilet soap largely depends, it should be carefully done. The number of
+times a soap should be milled depends upon the character of a soap being
+worked. It should of course be the object to mill with as high a
+percentage of moisture as possible. Should the soap become too dry it is
+advisable to add water directly, rather than wet soap, since water can
+more easily be distributed through the mass. As a general statement it
+may be said it is better policy to overmill a soap, rather than not mill
+it often enough.
+
+After the soap has been thoroughly milled it is ready for plodding. A
+_plodder_ is so constructed as to take the soap ribbons fed into the
+hopper by means of a worm screw and continuously force it under great
+pressure through a jacketed cylinder through which cold water circulates
+in the rear to compensate the heat produced by friction and hot water at
+the front, to soften and polish the soap which passes out in solid form
+in bars of any shape and size depending upon the form of the _shaping
+plate_ through which it is emitted. The bars run upon a _roller board_,
+are cut into the required length by a special _cake cutting table_,
+allowed to dry slightly and pressed either automatically or by a foot
+power _press_ in any suitable soap _die_. The finished cake is then
+ready for wrapping and after due time in stock reaches the consumer.
+
+Besides the various apparatus mentioned above there are many other parts
+for the full equipment of a modern soap plant, such as remelters, pumps,
+mixers, special tanks, power equipment, etc. As has been stated,
+however, practical experience will aid in judging the practicability as
+to installation of these. The various methods of powdering soap are,
+however, not generally known. Where a coarse powder is to be produced,
+such as is used for common washing powders, no great difficulty is
+experienced with the well known Blanchard mill. In grinding soap to an
+impalpable powder the difficulties increase. The methods adapted in
+pulverizing soaps are by means of disintegrators, pebble mills and
+chaser mills. The disintegrator grinds by the principle of attrition,
+that is, the material is reduced by the particles being caused to beat
+against each other at great velocity; a pebble mill crushes the
+substance by rubbing it between hard pebbles in a slowly revolving
+cylinder; the chaser mill first grinds the material and then floats it
+as a very fine powder above a curb of fixed height. The last method is
+particularly adapted for the finest of powder (140 mesh and over).
+
+
+
+
+CHAPTER III
+
+Classification of Soap-Making Methods.
+
+
+In the saponification of fats and oils to form soap through the agency
+of caustic alkalis, as has been stated, the sodium or potassium salts of
+the mixed fatty acids are formed. Sodium soaps are usually termed hard
+soaps, and potassium soaps soft. There are, however, a great many
+varieties of soaps the appearance and properties of which depend upon
+their method of manufacture and the oils or fats used therein.
+
+The various methods adopted in soap making may be thus classified:
+
+1. Boiling the fats and oils in open kettles by open steam with
+indefinite quantities of caustic alkali solutions until the finished
+soap is obtained; ordinarily named _full boiled soaps_. These may be
+sub-divided into (a) hard soaps with sodium hydrate as a base, in which
+the glycerine is recovered from the spent lyes; (b) hard soaps with soda
+as a base, in which the glycerine remains in the soap, e. g., marine
+cocoanut oil soaps; (c) soft potash soaps, in which the glycerine is
+retained by the soap.
+
+2. Combining the required amount of lye for complete saponification of a
+fat therewith, heating slightly with dry heat and then allowing the
+saponification to complete itself. This is known as the _cold process_.
+
+3. Utilizing the fatty acid, instead of the neutral fat, and combining
+it directly with caustic alkali or carbonate, which is incorrectly
+termed _carbonate saponification_, since it is merely neutralizing the
+free fatty acid and thus is not a saponification in the true sense of
+the word. No glycerine is directly obtained by this method, as it is
+usually previously removed in the clearage of the fat by either the
+Twitchell or autoclave saponification method.
+
+In the methods thus outlined the one most generally employed is the full
+boiled process to form a sodium soap. This method of making soap
+requires close attention and a knowledge which can only be obtained by
+constant practice. The stock, strength of lyes, heat, amount of salt or
+brine added, time of settling, etc., are all influencing factors.
+
+The principles involved in this process are briefly these:
+
+The fat is partly saponified with weak lyes (usually those obtained from
+a previous boiling in the strengthening change are used), and salt is
+added to grain the soap. The mass is then allowed to settle into two
+layers. The upper layer is partly saponified fat; the lower layer, or
+spent lye, is a solution of salt, glycerine, and contains any albuminous
+matter or any other impurity contained in the fat. This is known as the
+_killing_ or glycerine change. Strong lyes are now added and the fat
+entirely saponified, which is termed the _strengthening change_. The
+mass is then allowed to settle and the fluid soap run off above the
+"nigre." This operation is called the finish or _finishing_ change.
+
+The method may be more fully illustrated by a concrete example of the
+method of manufacture of a tallow base:
+
+    Charge--
+
+    Tallow              88 per cent.
+    Cocoanut oil        10 per cent.
+    Rosin w. w.          2 per cent.
+
+        Amount charge   10 tons
+
+About five tons of tallow and one ton of cocoanut oil are pumped or run
+into the soap kettle and brought to a boil with wet steam until it
+briskly comes through the hot fat. The caustic soda (strengthening lyes
+from former boilings may be used here) is gradually added by the
+distributing pipe, any tendency to thicken being checked by the
+introduction of small quantities of brine ("salt pickle"). If the lye is
+added too rapidly the soap assumes a granular appearance, indicating
+that the addition of same must be discontinued. Water should then be
+added and the mass boiled through until it again closes. When the
+addition of the proper amount of caustic soda is nearing its completion
+the soap gradually thins. The steam is now cut down to about one turn of
+the valve, and brine is rapidly added or salt shoveled in. In ten to
+fifteen minutes the steam again breaks through and, from the appearance
+of the soap, it can be seen whether sufficient brine has been added. A
+sample taken out by means of a long wooden paddle should show the soap
+in fine grains with the lyes running from it clear. The steam is then
+shut off and the soap allowed to settle from one and one-half to two
+hours. In all settlings the longer time this operation is permitted to
+continue, the better will the subsequent operations proceed.
+
+The mixture now consists of a partly saponified layer of fat above the
+spent lyes. The lyes are drawn off until soap makes its appearance at
+the exit pipe. The valve is then closed and the soap blown back into the
+kettle by steam. The lyes thus obtained are known as _spent lyes_, from
+which the glycerine is recovered. They should show an alkalinity of
+approximately 0.5 per cent. if the operation is carefully carried out.
+
+The remaining tallow is now added and the above operations repeated.
+
+After the spent lyes have been drawn off, the soap is closed with water
+and the proper percentage of rosin soap previously formed, or rosin
+itself is added to the mass in the kettle. More lye is then allowed to
+flow in until the mixture is up to "strength." This is usually tested
+by the "bite" on the tongue of a small cooled sample. After boiling
+until the steam comes through, the mass is grained with salt as before
+and allowed to settle one and one-half to three hours. These lyes, known
+as _strengthening lyes_ are run to storage to be used subsequently with
+fresh fat to take up the caustic soda contained therein.
+
+The soap is now ready for finishing and is first boiled through and
+tried for strength. A drop of phenolphthalein (1 per cent.
+phenolphthalein in 98 per cent. alcohol) is allowed to drop on the
+molten soap taken up on a trowel. The red color should be instantly
+produced and develop to a full deep crimson in a few seconds, or more
+lye must be added until this condition is realized. Should it flash a
+deep crimson immediately it is on the strong side. This cannot be
+conveniently remedied; it can only serve as a guide for the next boil,
+but in any case it is not of any serious consequence, unless it is too
+strong.
+
+With the steam on, the soap is now examined with a trowel which must be
+thoroughly heated by working it about under the surface of the hot soap.
+The appearance of the soap as it runs from the face of the trowel
+indicates its condition. It is not possible to absolutely describe the
+effect, which can only be properly judged by practice, yet the following
+points may serve as a guide. The indications to be noticed are the shape
+and size of the flakes of soap as the sample on the trowel breaks up and
+runs from the hot iron surface, when the latter is turned in a vertical
+position, as well as the condition of the iron surface from which the
+soap flakes have fallen. A closed soap will run slowly into a
+homogeneous sheet, leaving the trowel's surface covered with a thin
+layer of transparent soap; a grained mass will run rapidly down in tiny
+grains, about one-half an inch in diameter or less, leaving the hot
+trowel absolutely dry. The object of the finish is to separate the
+soaps of the lower fatty acids from those of the higher, and both from
+excess of liquid. A point midway between "open" and "closed" is required
+to arrive at this point.
+
+Having arrived at the above condition, the soap is allowed to settle
+anywhere from one to three days and then run off through the skimmer
+pipes to the nigre and framed or pumped to the tank feeding the drying
+machine.
+
+The stock thus obtained should be fairly white, depending upon the grade
+of tallow used and slightly alkaline to an alcoholic phenolphthalein
+solution. If removed at exactly the neutral point or with a content of
+free fat the soap will sooner or later develop rancidity. The soap thus
+obtained is an ordinary tallow base, and the one by far greatest used in
+the manufacture of toilet soaps. The percentage of cocoanut oil
+indicated is not fixed and may readily be varied, while in fine toilet
+soap the rosin is usually eliminated.
+
+In the manufacture of full boiled soda soaps in which no glycerine is
+obtained as a by-product, it being retained in the soap itself, the soap
+formed is known as a "run" soap. The process is used most extensively in
+the manufacture of marine soaps by which the method may be best
+illustrated. This soap is known as marine soap because of its property
+of readily forming a lather with salt water and is mostly consumed
+aboard vessels.
+
+Marine soaps are manufactured by first placing in the kettle a
+calculated amount of lye of 25 deg. to 35 deg. B., depending upon the
+amount of moisture desired in the finished soaps, plus a slight excess
+required to saponify a known weight of cocoanut oil. With open steam on,
+the cocoanut oil is then gradually added, care being taken that the soap
+does not froth over. Saponification takes place readily and when the oil
+is entirely saponified the finished soap is put through the process
+known as running. This consists in constantly pumping the mass from the
+skimmer pipe back into the top of the kettle, the object being to
+prevent any settling of the nigre or lye from the soap, as well as
+producing a homogeneous mass. It is customary to begin the
+saponification in the morning, which should be completed by noon. The
+soap is then run for about three hours and framed the next morning.
+After having remained in the frame the time required to solidify and
+cool, the soap is slabbed and cut into cakes. This process is difficult
+to carry out properly, and one not greatly employed, although large
+quantities of marine soap are purchased by the government for use in the
+navy and must fulfill certain specifications required by the purchasing
+department.
+
+In making potash soaps it is practically impossible to obtain any
+glycerine directly because of the pasty consistency of the soap, and no
+graining is possible because the addition of salt to a soft soap, as
+already explained, would form a soda soap. Large quantities of soft
+soaps are required for the textile industries who desire mostly a strong
+potash soap, and the large number of automobiles in use at the present
+time has opened a field for the use of a soft soap for washing these. A
+soap for this purpose must be neutral so as not to affect the varnish or
+paint of automobiles.
+
+A suitable soap for textile purposes may be made as follows:
+
+    Red oil                         80     parts
+    House grease                    20     parts
+    Caustic soda lye, 36 degs. B.    3     parts
+    Carbonate of potash              5-1/2 parts
+    Caustic potash                  23-1/4 parts
+
+Olive oil, corn oil, soya bean oil, olive oil foots or cottonseed oil
+may replace any of the above oils. A large quantity of cottonseed oil
+will cause the soap to fig.
+
+To carry out the process, the caustic potash and carbonate of potash are
+dissolved and placed in the kettle together with the soda lye, and the
+oils added. This is most satisfactorily accomplished by being finished
+the day before the boiling is begun. The next day the boiling is begun
+and water added to bring the soap up to the desired percentage of fatty
+acid, due allowance being made for the water formed by the condensation
+of the open steam in boiling. Care must be taken that the soap in the
+kettle does not swell and run over during the saponification. A good
+procedure is to use open steam for a period of about two hours, then
+close the valve and allow the saponification to continue without
+boiling, and repeat this until it is entirely saponified. After the
+saponification has been completed the soap is briskly boiled all day and
+the proper corrections made; that is, if too alkaline, more oil is
+added, and if free fat is present, more potash. About 2 per cent.
+carbonate of potash is the proper amount for a soap containing 50 per
+cent. fatty acid. The soap is sampled by allowing it to drop on a clean,
+cold glass surface. In so doing, the soap should not slide or slip over
+the glass surface when pressed thereon, but should adhere to the glass,
+or it is too alkaline. A sample worked between the fingers showing too
+much stringiness should have more strong potash and oil added. A sample
+taken out in a pail and allowed to cool over night will serve as a guide
+as to the body of the soap in the kettle. When the soap has thus been
+properly finished it is run into barrels.
+
+For an automobile soap the following is a good working formula:
+
+    Corn oil                       1,000 parts
+    Potash lye, 31-1/2 degs. B.      697 parts
+
+Proceed as in the directions just given for textile soap in placing
+charge in the kettle. When the kettle is boiling up well, shut off the
+steam and the saponification will complete itself. The soap may be run
+into the barrels the next day.
+
+A heavy soap with a smaller percentage of fat may be made as follows:
+
+    Corn oil                       1,000 parts
+    Potash lye, 24-1/2 degs. B.      900 parts
+
+Boil until the soap bunches, and shovel the finished soap into barrels.
+Upon standing it will clear up. By the addition of more water the yield
+of soap per pound of oil may be run up to 300 per cent.
+
+After soft soaps have been allowed to stand for some time the phenomenon
+known as "figging" often occurs. This term is applied to a
+crystalline-like formation, causing spots of a star-like shape
+throughout the soap. This is undoubtedly due to the stearine content of
+the soap crystallizing out as it cools, and forming these
+peculiarly-shaped spots. It more generally occurs in the winter and may
+be produced artificially by adding a small quantity of soda to the
+potash lye before saponification.
+
+The oils usually employed in the manufacture of potash soaps are
+cottonseed oil, corn oil, soya bean oil, olive oil foots, red oil,
+cocoanut oil, grease and the various train oils. The usual percentage
+yield is from 225 per cent. to 300 per cent., based upon the weight of
+oil used. In calculating the weight of a soft soap it is to be
+remembered that since potassium has a higher molecular weight (56) than
+sodium (40), the corresponding soap formed is that much greater in
+weight when compared with a sodium soap. Rosin may be added to soft
+soaps as a cheapening agent.
+
+
+COLD PROCESS.
+
+The cold process for manufacturing soap is the simplest method of soap
+making, and the equipment required is small when compared to the other
+methods. All the more expensive equipment that is necessary is a
+crutcher, a tank to hold the lye, frames, a slabber or cutting table,
+and a press. Yet, in spite of the simplicity of thus making soap, the
+disadvantages are numerous for the production of a good piece of soap.
+The greatest difficulty is to obtain a thorough combination of oil or
+fat and lye so that there will not be an excess of one or the other in
+the finished soap. At its best there is either a considerable excess of
+free fat which later exhibits itself in producing rancidity or
+uncombined caustic, which produces an unpleasant effect on the skin when
+the soap is consumed for washing. The latter objection, of course, can
+only be applied to toilet soaps.
+
+Cocoanut oil is used very largely in the manufacture of cold-made soaps
+as it is well adapted for this purpose, although it is by no means true
+that other oils may not be employed. Since by this process of
+manufacture no impurity contained in the fat or oil is removed in the
+making of the soap, it is necessary that in order to obtain a fine
+finished product, any impurity contained in these may be removed if
+present, or that the fats be as pure as can be obtained. If inedible
+tallow is used for cold-made soap, it is advisable to bleach it by the
+Fuller's Earth Process.
+
+The carrying out of this method is best illustrated by an example of a
+cold-made cocoanut oil soap.
+
+    Charge:
+
+    Cochin cocoanut oil          846 parts
+    Lye (soda), 35 degs. B.      470 parts
+    Water                         24 parts
+
+The oil is run into the crutcher and the temperature of the oil raised
+to 100 degs. F. by dry steam. The lye and water are at room temperature.
+After all the oil is in the crutcher, the lye and water are slowly added
+to prevent any graining of the soap. Toward the end the lye may be added
+more rapidly. When all the lye is in, the mass is crutched for about
+three hours, or until upon stopping the crutcher a finger drawn over the
+surface of the soap leaves an impression. If this condition is not
+realized, the soap must be mixed until such is the case. Having arrived
+at this point, the mixture is dropped into a frame which should remain
+uncovered. The heat produced by the further spontaneous saponification
+will cause the soap to rise in the middle of the frame. After having set
+for some days it is ready to be slabbed and cut into cakes.
+
+A potash soap may be made by the cold process just as readily as a soda
+soap. Soaps of this type may be made by either of these formulae in a
+crutcher:
+
+    Olive oil foots                                  600
+    Potash lye, 18 degs. B. hot, 20 degs. B. cold    660
+
+                    or
+
+    Corn oil                                         800
+    Rosin                                            200
+    Potash lye, 27 degs. B.                          790
+    Water                                            340
+
+Heat the oils to 190 degs. F., add the lye and crutch until the soap
+begins to bunch, when it is ready to be run into barrels where the
+saponification will be completed.
+
+Semi-boiled soaps differ from those made by the cold process in
+temperature. In making semi-boiled soaps the fats are usually heated to
+140° F. The addition of the lye raises the temperature to 180°--200° F.
+when saponification takes place.
+
+
+CARBONATE SAPONIFICATION.
+
+The method of the formation of soap by the utilization of the fatty acid
+directly, from which the glycerine has already been removed by some
+method of saponification other than with caustic soda, and neutralizing
+this with alkali, is becoming increasingly popular. The glycerine is
+more easily recovered from a previous cleavage of the fats or oils, but
+a soap made from the mixed fatty acids thus obtained is seldom white in
+color and retains an unpleasant odor. Since soda ash or sodium carbonate
+is cheaper than caustic soda and readily unites with a fatty acid, it is
+used as the alkali in the carbonate saponification. The process is
+similar to that already given under Rosin Saponification. About 19 per
+cent. by weight of the fatty acids employed of 58 per cent. soda ash is
+dissolved in water until it has a density of 30 degs. B., and the
+solution is run into the kettle, which is usually equipped with a
+removable agitator. The fatty acids, previously melted, are then slowly
+added while the mixture is boiled with open steam and agitated with the
+stirring device. The fatty acids instantly unite with the carbonate and
+rise in the kettle, due to the generation of carbon dioxide, and care
+must be exercised to prevent boiling over. After all the fatty acid has
+been added, and the mass is boiled through the saponification must be
+completed with caustic soda, as there is as yet no practical method
+known which will split a fat entirely into fatty acid and glycerine.
+Thus about 10 per cent. of the fatty acids are true neutral fats and
+require caustic soda for their saponification. This is then added and
+the soap completed, as in full-boiled soaps.
+
+In carrying out this method upon a large scale, large
+sue\Neanderthal\doroteer\Neanderthal\Josephine\ quantities of carbon
+dioxide are formed during the boiling of the soap, which replaces a
+quantity of the air contained therein. The kettle room should therefore
+be well ventilated, allowing for a large inflow of fresh air from out of
+doors.
+
+
+
+
+CHAPTER IV
+
+Classification of Soaps.
+
+
+In considering the many different varieties of soaps, their
+classification is purely an arbitrary one. No definite plan can be
+outlined for any particular brand to be manufactured nor can any very
+sharp distinction be drawn between the many soaps of different
+properties which are designated by various names. It is really a
+question to what use a soap is to be put, and at what price it may be
+sold. There is, of course, a difference in the appearance, form and
+color, and then there are soaps of special kinds, such as floating
+soaps, transparent soaps, liquid soaps, etc., yet in the ultimate sense
+they are closely allied, because they are all the same chemical
+compound, varying only in their being a potash or soda soap, and in the
+fatty acids which enter into combination with these alkalis. Thus we can
+take a combination of tallow and cocoanut oil and make a great many
+presumably different soaps by combining these substances with caustic
+soda, by different methods of manufacture and by incorporating various
+other ingredients, as air, to form a floating soap, alcohol to make a
+transparent soap, dyestuffs to give a different color, etc., but
+essentially it is the same definite compound.
+
+The manufacturer can best judge the brand of soaps he desires to
+manufacture, and much of his success depends upon the name, package,
+shape, color or perfume of a cake of soap. It is the consumer whom he
+must please and many of the large selling brands upon the market today
+owe their success to the above mentioned details. The great majority of
+consumers of soap know very little concerning soap, except the fact
+that it washes or has a pleasant odor or looks pretty, and the
+manufacturer of soap must study these phases of the subject even more
+carefully than the making of the soap itself.
+
+For a matter of convenience we will classify soap under three general
+divisions:
+
+I. Laundry soaps, including chip soaps, soap powders and scouring soaps.
+
+II. Toilet soaps, including floating soap, castile soap, liquid soap,
+shaving soap, etc.
+
+III. Textile soaps.
+
+
+LAUNDRY SOAP.
+
+The most popular household soap is laundry soap. A tremendous amount of
+this soap is consumed each day in this country, and it is by far
+manufactured in larger quantities than any other soap. It is also a soap
+which must be sold cheaper than any other soap that enters the home.
+
+The consumers of laundry soap have been educated to use a full boiled
+settled rosin soap and to make a good article at a price this method
+should be carried out, as it is the one most advisable to use. The
+composition of the fats entering into the soap depends upon the market
+price of these, and it is not advisable to keep to one formula in the
+manufacture of laundry soap, but rather to adjust the various fatty
+ingredients to obtain the desired results with the cheapest material
+that can be purchased. It is impossible to use a good grade of fats and
+make a profit upon laundry soap at the price at which it must be
+retailed. The manufacturer of this grade of soap must look to the
+by-product, glycerine, for his profit and he is fortunate indeed if he
+realizes the entire benefit of this and still produces a superior piece
+of laundry soap.
+
+
+SEMI-BOILED LAUNDRY SOAPS.
+
+It is advantageous at times to make a laundry soap by a method other
+than the full boiled settled soap procedure as previously outlined. This
+is especially the condition in making a naphtha soap, in which is
+incorporated naphtha, which is very volatile and some of the well known
+manufacturers of this class of soap have adopted this process entirely.
+A laundry soap containing rosin cannot be advantageously made by the
+cold process, as the soap thus made grains during saponification and
+drops a portion of the lye and filling materials. By making a
+semi-boiled soap this objection is overcome. The half boiled process
+differs from the cold process by uniting the fats and alkalis at a
+higher temperature.
+
+To carry out this process the following formulae have been found by
+experience to give satisfactory results.
+
+                     I.         lbs.
+
+    Tallow                       100
+    Rosin                         60
+    Soda Lye, 36° B.              80
+
+                    II.
+
+    Tallow                       100
+    Rosin                         60
+    Silicate of Soda              25
+    Soda Lye, 36° B.              85
+
+                    III.
+
+    Tallow                       100
+    Rosin                        100
+    Lye, 36° B.                  105
+    Silicate of Soda              25
+    Sal Soda Solution             20
+
+In any of these formulas the sodium silicate (40° B.) may be increased
+to the same proportion as the fats used. By so doing, however, twenty
+pounds of 36° B. lye must be added for every hundred pounds of silicate
+additional to that indicated or in other words, for every pound of
+silicate added 20 per cent. by weight of 36° B. lye must be put into the
+mixture. The rosin may also be replaced by a previously made rosin soap.
+
+To make a semi-boiled soap, using any of the above formulae, first melt
+the rosin with all or part of the fat, as rosin when melted alone
+readily decomposes. When the mixture is at 150° F. run it into the
+crutcher and add the lye. Turn on sufficient dry steam to keep the
+temperature of the soap at about 150° F. in the winter or 130° F. in
+summer. After the mass has been mixed for half an hour, by continuously
+crutching the soap it will at first thicken, then grain and it may again
+become thick before it becomes smooth. When the mass is perfectly smooth
+and homogeneous drop into a frame and crutch in the frame by hand to
+prevent streaking. After standing the required length of time the soap
+is finished into cakes as usual.
+
+
+SETTLED ROSIN SOAP.
+
+Settled rosin soaps are made from tallow, grease, cottonseed oil,
+bleached palm oils of the lower grades, corn oil, soya bean oil, arachis
+oil, distilled garbage grease, cottonseed foots or fatty acids together
+with an addition of rosin, varying from 24 per cent. to 60 per cent. of
+the fatty acids which should titer from 28 to 35. A titer lower than 28
+will prevent the finished kettle of soap from being capable of later
+taking up the filling materials. As has already been stated under
+hardened oils, these being very much higher in titer allow a greater
+percentage of rosin to be added. Thus hardened fish oils and cottonseed
+oil are gradually being more extensively employed in soaps of this
+character.
+
+The procedure of handling the kettle is similar to that given under full
+boiled soap. The stock is steamed out into a settling tank and allowed
+to settle over night, after which it is pumped into the soap kettle.
+Having stocked the kettle, open steam is turned on and 10°-12° B. lye is
+run in, while using a steam pressure of ninety to one hundred pounds in
+order to prevent too great a quantity of condensation of the steam, the
+water thus being formed weakening the lye. If a steam pressure of fifty
+to sixty pounds is available, a stronger lye (20° B.) should be added.
+Care must be taken not to allow the lye to flow in too rapidly or the
+soap will not grain. The saponification is only attained by prolonged
+boiling with sufficient lye of proper strength. When saponification has
+taken place, the mass begins to clear and a sample taken out with a
+paddle and cooled should show a slight pink with a 1 per cent. alcoholic
+phenolphthalein solution.
+
+It may be stated here that in using this indicator or any other to test
+the alkalinity of soap, the soap should always be cooled and firm, as
+whenever water is present, the dissociation of the soap thereby will
+always react alkaline. When this state is reached the mass is ready for
+graining, which is accomplished by distributing salt brine or pickle or
+spreading dry salt over the surface of the soap. The kettle is then
+thoroughly boiled until the mass shows a soft curd and the lye drops
+clearly from a sample taken out with a trowel or paddle. The steam is
+then shut off and the soap allowed to settle over night. The lyes are
+then run off to the spent lye tank for glycerine recovery. In
+saponifying a freshly stocked kettle it is apt to bunch. To prevent this
+salt is added at various times to approximately one per cent. of the fat
+used.
+
+If, by any possibility the soap has bunched, this condition may be
+remedied by the addition of more strong lye and boiling until it is
+taken up. To work a kettle to its full capacity it is advisable to make
+two "killing" changes. First add about 75 per cent. of the fat and grain
+as directed. Run off the spent lyes and then add the remainder of the
+stock and repeat the process. When the spent lye has been run to
+storage, the open steam is again turned on and 18° B. lye gradually
+allowed to run in. The rosin is now broken up and put into the kettle,
+or a previously made rosin soap is pumped in.
+
+Lye is then added until the soap has a sharp taste after about three
+hours of continuous boiling, or when the soap is in the closed state.
+More lye should then be run into the kettle to grain the soap well, the
+grain not being too small. Then allow the soap to settle over night and
+draw off the strengthening lye. The next day again boil up the kettle
+and add water until the soap thins out and rises or swells high in the
+kettle. A sample taken out at this stage upon a hot trowel should run
+off in large flakes. The surface of the soap should be bright and shiny.
+
+If the sample clings to the trowel, a slight addition of lye will remedy
+this defect. The kettle is then allowed to rest, to drop the nigre and
+to cool for some time, depending upon the size of the kettle. The proper
+temperature is such that after having been pumped to the crutcher and
+the filling materials having been added, a thermometer placed into the
+mass should indicate 128°-135° F. after the crutcher has run from ten to
+fifteen minutes. The filling material may consist of from 7-9 per cent.
+of sal soda solution, 36°-37° B. warm or just enough to close up the
+soap and make it rise high in the center of a screw crutcher and make it
+cling close to a warm trowel. Other fillers such as outlined below are
+added at this point.
+
+An addition of from 2-3 per cent. of a special mineral oil for this
+purpose will impart a finish to the soap and 3-5 per cent. starch added
+prevents the soap from cracking in the frames. Other filling material as
+silicate of soda, borax, talc or silex are used. After the filling
+material has been thoroughly crutched through the soap it is framed,
+and, after being several days in the frame to solidify and cool the soap
+is ready for slabbing, pressing and wrapping.
+
+In order to more definitely illustrate the composition of the mixture of
+fats and oils entering into the formation of a laundry soap a typical
+formula may be given for such a soap containing 40 per cent. rosin added
+to the amount of fats used:
+
+                                  lbs.
+    Grease                      7,000
+    Tallow                      4,000
+    Corn Oil                    7,000
+    Cottonseed Oil              3,000
+    Rosin                       8,400
+
+The following have been found to be satisfactory filling materials and
+are calculated upon the basis of a 1,400-pound frame of soap.
+
+                          I.             lbs.
+
+    Sodium Silicate, 38°-40° B.          100
+    Mineral Oil                           25
+    Sal Soda Solution, 36° B.             80
+    Borax                                  1
+
+                         II.
+
+    Sal Soda Solution, 36° B.             80
+    Mineral Oil                           25
+    Sodium Silicate                       60
+
+                        III.
+    Soda Ash                              10
+    Sal Soda                              55
+    Sodium Silicate                      115
+    Mineral Oil                           40
+    Brine (Saturated Solution)            10
+    Sodium Silicate, 38°-40° B.          100
+
+                         IV.
+    Sodium Silicate                      100
+    Silex or Talc                        200
+    Soda Ash                              50
+
+                         V.
+
+    Sal Soda Solution, 36° B.             90
+    Sodium Silicate                    50-60
+    Mineral Oil                           25
+    Borax Solution, 25° B. (hot)          15
+
+
+CHIP SOAP.
+
+Chip soap is used extensively in laundries but is also used largely in
+other branches. It may be made either as a settled soap or by the cold
+made process.
+
+To make a full boiled settled chip soap, proceed as directed under
+settled laundry soap. The kettle is stocked with light grease or a
+mixture of grease with corn oil or other cheap oils. For this kind of
+soap the rosin is eliminated.
+
+Chip soap may be filled as well as laundry soap. This is done in the
+crutcher and the following adulterations are suitable.
+
+                                   lbs.
+    Settled Soap                   700
+    Soda Ash                        35
+    Sodium Silicate                215
+                     or
+    Settled Soap                   700
+    Silicate of Soda               560
+    Soda Ash                        18
+    Carbonate of Potash, 26° B.     50
+
+The cheapest method of drying is by running this soap through a drying
+machine and this is the procedure usually carried out for making dried
+chip soap.
+
+
+COLD MADE CHIP SOAPS.
+
+To make chip soaps by the cold process a sweet tallow of low percentage
+of free fatty acid should be employed. The tallow is heated to 120° to
+135° F. and the lye run in slowly at first and then the silicate of soda
+is added. The mass is then mixed until a finger drawn through the soap
+leaves a slight impression, then dropped into frames or barrels. Soaps
+containing a small percentage of fat should be well covered in the frame
+for twenty-four hours to retain their heat and insure proper
+saponification. The following formulae are suitable:
+
+                        I.                lbs.
+    Tallow                               1,200
+    Soda Lye, 35° B.                       850
+    Sodium Silicate                        750
+
+                      II.
+    Tallow                                 475
+    Ceylon Cocoanut Oil                    100
+    Soda Lye, 37° B.                       325
+    Potash Lye, 37° B.                      56
+
+                      III.
+    Tallow                                 500
+    Soda Lye, 37-1/2° B.                   297
+    Sodium Silicate                        416
+    Potash Lye, 37-1/2° B.                  37-1/2
+
+                       IV.
+    Tallow                                 450
+    Soda Lye, 37-1/2° B.                   255
+    Sodium Silicate                        450
+    Potash Lye, 37-1/2° B.                  50
+
+                       V.
+    Tallow                                 450
+    Soda Lye, 35° B.                       470
+    Sodium Silicate                        650
+
+                      VI.
+    Tallow                                 420
+    Sodium Silicate                        600
+    Soda Lye, 37-12° B.                    270
+
+
+UNFILLED CHIP SOAP.
+
+A very good grade of chip soap is made by employing no filling material
+whatsoever, but unfortunately the price of this soap has been cut to
+such an extent that these can not compete with a filled chip. A number
+of the best soaps of this kind are made from a settled soap using a
+light grease with corn oil. A soap of this nature is made as follows.
+
+                                          lbs.
+    Settled Soap                           800
+    Sal Soda Solution, 36°-37° B.          252
+    Soda Ash                               182
+
+If this soap is run into frames it may be stripped and chipped in two
+days.
+
+
+SOAP POWDERS.
+
+Soap powders have become so great a convenience as a general cleansing
+agent that to eliminate them from the household necessities would mean
+much unnecessary energy and work to the great number of consumers of
+this product. They may be manufactured so cheaply and still be
+efficient, that their use has almost become universal for cleansing and
+scouring purposes. The uses to which soap and scouring powders are
+adapted are too well known to enter into a description of their
+employment. Since they offer a greater profit to the manufacturer than
+ordinary household soap, many brands are extensively advertised.
+
+Numerous combinations for soap powders might be cited and it is a simple
+matter to vary the ingredients as to fat content and manufacture a
+powder of this sort as low as a cent a pound. Many substances are
+incorporated with soap, such as salt, soda ash, tripoli, crushed
+volcanic deposits, ground feldspar, infusorial earth of various kinds,
+silex, etc. In addition to these various fillers, compounds with true
+cleansing and bleaching properties, in addition to soap, are added, such
+as the salts of ammonium (sal ammoniac, carbonate of ammonia), sodium
+perborate and the peroxides of various metals. The public, however, have
+been accustomed to receive a large package of soap or scouring powder
+for a small amount of money and it is a difficult matter for the
+manufacturer to add more expensive substances of this nature to his
+product, to increase its efficiency, without raising the price or
+decreasing the size of the package.
+
+In manufacturing soap powders, the dried soap chips might be mixed with
+the filler and alkali and then pulverized. This method is not
+extensively employed nevertheless. The process which is the most
+economical is one whereby the ingredients are mixed in a specially
+adapted mixer for heavy material until dry and then run directly to the
+crusher and pulverizer, after which it is automatically packed, sealed
+and boxed. Another method of procedure is to run out the mixture from
+the crutcher to the frames, which are stripped before the soap cools,
+and is cut up at once, for if it hardens it could not be cut with wires.
+It is better, however, to run the mixture into sheets upon a specially
+constructed floor and break up the mass when cool.
+
+Formulae for soap powders which have been found to be suitable for
+running dry in the mixer follow:
+
+                        I
+    Soda ash, 58 per cent.                   42 lbs.
+    Silica                                  220  "
+    Settled soap (usually cottonseed).       25  "
+    Salt                                     10  "
+
+                       II
+    Soap (settled cottonseed)                40 lbs.
+    Soda ash, 58 per cent.                   60  "
+
+                      III
+    Settled soap                            100 lbs.
+    Soda ash, 58 per cent.                  400  "
+
+Fillers in varying proportions may replace the soda ash in the above
+formulae. It is of course understood that the soap has been previously
+made and run as molten soap into the crutcher.
+
+The following soap powders will not dry up in the crutcher upon running,
+but are of the class which may be framed or run on the floor to
+solidify:
+
+
+                         I
+    Soap                                 850 lbs.
+    Filler                               400  "
+    Sal soda solution, 20 degs. B        170  "
+
+                       II
+    Soap                                 650 lbs.
+    Filler                               550  "
+    Sal soda solution, 20 degs. B.       340  "
+
+                      III
+    Soap                                  80 lbs.
+    Filler                               550  "
+    Sal soda solution                    170  "
+
+                      IV
+    Soap (settled tallow)                800 lbs.
+    Filler                               400  "
+    Sal soda solution                    170  "
+    Water                                100  "
+
+                       V
+
+First saponify 100 parts house grease and 100 parts ordinary grease and
+make a run soap. Then use in crutcher either:
+
+    Soap                                 400 lbs.
+    Filler                               575  "
+    Hot water                             60  "
+                         or
+    Soap                                 200 lbs.
+    Hot water                            200  "
+    Filler                               625  "
+
+It would be a simple matter to write numerous additional formulae, but
+the above are typical. The manufacturer must judge for himself just what
+filling material to use. The filler indicated in the above formulae is
+therefore left open. A few formulae for more expensive powders than
+those given recently appeared among others in the "Seifensieder
+Zeitung"[9]:
+
+
+                     I
+
+    Powdered soap                         90 lbs.
+    Sodium perborate                      10  "
+
+The perborate should be added when the powder is perfectly dry or it
+loses its bleaching properties.
+
+                     II
+
+    Soap powder, 20 per cent. fat.
+    Cocoanut oil fatty acids              25 lbs.
+    Olein                                 25  "
+    Bone fat                              70  "
+    Soda lye, 30 degs. B.                 90  "
+    Water                                150  "
+    Ammonium carbonate                   125  "
+
+                     III
+
+    Soap powder, 10 per cent. fat.
+    Cocoanut oil fatty acids              20 lbs.
+    Olein                                 10  "
+    Bone fat                              20  "
+    Soda lye, 30 degs. B.                 30  "
+    Water                                175  "
+    Ammonium carbonate                   175  "
+
+
+LIGHT OR FLUFFY POWDERS.
+
+Light or fluffy powders containing 35-45% moisture can be made in two
+ways. The first method requiring a minimum equipment is to mix the
+powder and sal soda in a mixer, allow it to stand in frames for a week
+to crystallize or spread it on the floor for a few hours to dry and then
+grinding it.
+
+The continuous method finishes the powder in a few minutes and with a
+minimum amount of labor. By this process the various ingredients, soap,
+soda ash solution, etc., are measured, run by gravity into the mixer,
+mixed and the molten mass run over the crystallizer or chilling rolls
+thru which either cold water or brine is pumped. From the roll the
+powder is scraped off clean by a knife, passes to a screen which sends
+the tailings to a grinder, falls into a storage bin from whence it is
+weighed and packed by an automatic weighing machine into cartons made up
+in most cases by another machine. Due to the large percentage of
+moisture contained in these soap powders the carton is generally wrapped
+in wax paper to aid in the prevention of the escape of moisture.
+
+
+SCOURING POWDERS.
+
+Scouring powders are very similar to soap powders and differ only in the
+filler used. We have already considered these fillers under scouring
+soap, from which they do not differ materially. They are usually
+insoluble in water to aid in scouring. The mixer used for substances of
+this kind in incorporating the soap and alkali must be of strong
+construction.
+
+
+SCOURING SOAP.
+
+Scouring soaps resemble soap powders very closely in their composition,
+in that they are a combination of soap and filling material. Since more
+lather is required from a scouring soap than in soap powders, a cocoanut
+oil soap is generally used. The usual filling material used is silex.
+The greatest difficulty in the manufacture of scouring soap is the
+cracking of the finished cake. This is usually due to the incorporation
+of too great an amount of filler, or too high a percentage of moisture.
+
+In manufacturing these soaps the cocoanut oil is saponified in the
+crutcher with 38 degs. B. lye, or previously saponified as a run soap,
+as already described under "Marine Soaps." To twenty-five parts of soap
+are added a percentage of 38 degs. B. sal soda or soda ash solution,
+together with a small quantity of salt brine. To this mixture in the
+crutcher seventy-five parts of silex are then added, and a sufficient
+amount of hot water to make the mass flow readily. Care must be
+exercised to not add too great a quantity of water or the mass will
+crack when it cools. The mass is then framed and cut before it sets, or
+poured into molds and allowed to set. While silex is the most
+extensively used filler for scouring soaps, it is feasible to
+incorporate other substances of like character, although it is to be
+remembered that the consumer is accustomed to a white cake, such as
+silex produces. Any other material used to replace silex should also be
+as fine as this product.
+
+
+FLOATING SOAP.
+
+Floating soap occupies a position midway between laundry and toilet
+soap. Since it is not highly perfumed and a large piece of soap may be
+purchased for small cost, as is the case with laundry soap, it is
+readily adaptable to general household use. Floating soap differs from
+ordinary soap in having air crutched into it which causes the soap to
+float in water. This is often advantageous, especially as a bath soap,
+and undoubtedly the largest selling brand of soap on the American market
+today is a floating soap.
+
+In the manufacture of floating soap a high proportion of cocoanut oil is
+necessary. A most suitable composition is one part cocoanut oil to one
+part of tallow. This is an expensive stock for the highest grade of soap
+and is usually cheapened by the use of cottonseed or various other
+liquid oils. Thus it is possible to obtain a floating soap from a kettle
+stocked with 30 per cent. cocoanut oil, 15 per cent. cottonseed oil and
+55 per cent. tallow. With this quality of soap, however, there is a
+possibility of sweating and rancidity, and of the soap being too soft
+and being poor in color.
+
+The process of manufacture is to boil the soap in an ordinary soap
+kettle, after which air is worked into the hot soap by a specially
+constructed crutcher, after which the soap is framed, slabbed, cut into
+cakes and pressed.
+
+Concerning the boiling of the soap, the saponification must be carefully
+carried out, as the high proportion of cocoanut oil may cause a violent
+reaction in the kettle causing it to boil over.
+
+The method of procedure is the same as for a settled soap up to the
+finishing. When the mass is finally settled after the finish, the soap
+should be more on the "open" side, and the object should be to get as
+long a piece of goods as possible.
+
+Due to its high melting point, a much harder crust forms on the surface
+of a floating soap and in a greater proportion than on a settled soap
+during the settling. In a large kettle, in fact, it has been found
+impossible to break through this crust by the ordinary procedure to
+admit the skimmer pipe. Much of the success of the subsequent operations
+depends upon the completeness of the settling, and in order to overcome
+the difficulties occasioned by the formation of the crust everything
+possible should be done in the way of covering the kettle completely to
+enable this period of settling to continue as long as possible.
+
+When the soap is finished it is run into a specially constructed U-shape
+crutcher, a Strunz crutcher is best adapted to this purpose, although a
+rapidly revolving upright screw crutcher has been found to give
+satisfaction upon a smaller scale, and a sufficient quantity of air
+beaten into the soap to make it light enough to float. Care must be
+taken not to run the crutcher too rapidly or the soap will be entirely
+too fobby. During this operation the mass of soap increases in bulk,
+and after it has been established how much air must be put into the soap
+to satisfy the requirements, this increase in bulk is a criterion to
+estimate when this process is completed.
+
+It is of course understood that the longer the crutching continues the
+greater quantity of air is incorporated and the increase of volume must
+be established for a particular composition by sampling, cooling the
+sample rapidly and seeing if it floats in water. If the beating is
+continued too long an interval of time, the finished soap is too spongy
+and useless.
+
+The temperature of the mass during crutching is most important. This
+must never exceed 158 degrees F. At 159 degrees F. the operation is not
+very successful, yet the thermometer may indicate 140 degrees F. without
+interfering with this operation. If, however, the temperature drops too
+low, trouble is liable to be met with, by the soap solidifying too
+quickly in the frames.
+
+When the crutching is completed, the soap is allowed to drop into frames
+through the valve at the bottom of the crutcher and rapidly crutched by
+the hand in the frames to prevent large air spaces and then allowed to
+cool. It is an improvement to jolt the frames as they are drawn away as
+this tends to make the larger air bubbles float to the surface and thus
+reduce the quantity of waste. When the soap has cooled, the frame is
+stripped and the soap slabbed as usual. At this point a layer of
+considerable depth of spongy soap will be found to have formed. This of
+course must be cut away and returned to the kettle. The last few slabs
+are also often rejected, inasmuch as the weight of the soap above them
+has forced out so much of the air that the soap no longer floats. As a
+fair average it may be estimated that not more than 50 to 60 per cent.
+of the soap in the kettle will come out as finished cakes. the
+remaining 40 to 50 per cent. being constituted by the heavy crust in the
+kettle, the spongy tops, the bottom slabs and scrapings. This soap is of
+course reboiled and consequently not lost, but the actual cakes obtained
+are produced at a cost of practically double labor.
+
+It is advisable to add a small quantity of soap blue color to the mass
+while crutching to neutralize the yellowish tint a floating soap is
+liable to have.
+
+Some manufacturers add a percentage of carbonate of soda, about 3 per
+cent., to prevent the soap from shrinking. Floating soap may also be
+loaded with sodium silicate to the extent of about 5 per cent.
+
+
+TOILET SOAP.
+
+It is not a simple matter to differentiate between toilet soaps and
+various other soaps, because numerous soaps are adaptable to toilet
+purposes. While some soaps of this variety are manufactured by the cold
+made or semi-boiled process, and not milled, the consumer has become
+accustomed to a milled soap for general toilet use.
+
+The toilet base most extensively employed is a tallow and cocoanut base
+made as a full boiled settled soap. The manufacture of this base has
+already been outlined and really needs no further comment except that it
+is to be remembered that a suitable toilet soap should contain no great
+excess of free alkali which is injurious to the skin. Cochin cocoanut
+oil is preferable to the Ceylon cocoanut oil or palm kernel oil, to use
+in conjunction with the tallow, which should be a good grade and color
+if a white piece of goods is desired. The percentage of cocoanut oil may
+be anywhere from 10 to 25 per cent., depending upon the kind of lather
+required, it being remembered that cocoanut oil increases the lathering
+power of the soap.
+
+In addition to a tallow base, numerous other oils are used in the
+manufacture of toilet soaps, especially palm oil, palm kernel oil, olive
+oil and olive oil foots, and to a much less extent arachis or peanut
+oil, sesame oil and poppy seed oil, oils of the class of cottonseed,
+corn and soya bean oils are not adapted to manufacturing a milled soap,
+as they form yellow spots in a finished cake of soap which has been kept
+a short time.
+
+Palm oil, especially the Lagos oil, is much used in making a palm base.
+As has already been stated, the oil is bleached before saponification. A
+palm base has a yellowish color, a sweetish odor, and a small quantity
+added to a tallow base naturally aids the perfume. It is especially good
+for a violet soap. The peculiarity of a palm oil base is that this oil
+makes a short soap. By the addition of some tallow or twenty to
+twenty-five per cent. of cocoanut oil, or both, this objection is
+overcome. It is a good plan in using a straight palm base to add a
+proportion of yellow color to hold the yellowish tint of this soap, as a
+soap made from this oil continues bleaching upon exposure to air and
+light.
+
+Olive oil and olive oil foots are used most extensively in the
+manufacture of castile soaps. The peculiarity of an olive oil soap is
+that it makes a very slimy lather, and like palm oil gives the soap a
+characteristic odor. An olive oil soap is usually considered to be a
+very neutral soap and may readily be superfatted. Much olive oil soap is
+used in bars or slabs as an unmilled soap and it is often made by the
+cold process. Peanut oil or sesame and poppy seed oil often replaces
+olive oil, as they form a similar soap to olive oil.
+
+In the manufacture of a toilet soap it is hardly practical to lay down a
+definite plan for the various bases to be made. From the combination of
+tallow, palm oil, cocoanut oil, palm kernel oil, olive oil and olive oil
+foots, a great many bases of different proportions might be given. The
+simplest method is to make a tallow base, a palm base and an olive oil
+base. Then from these it is an easy matter to weigh out any proportion
+of these soap bases and obtain the proper mixture in the mill. If,
+however, as is often the case, a large quantity of soap base of certain
+proportions of these, four or even more of these fats and oils is
+required, it is not only more economical to stock the kettle with the
+correct proportion of these oils, but a more thorough mixture is thus
+obtained by saponifying these in the kettle. In view of the fact that it
+is really a question for the manufacturer to decide for himself what
+combination of oils he desires for a particular soap we will simply
+outline a few typical toilet soap bases in their simplest combination.
+It is understood that these soaps are suitable for milled soaps and are
+to be made as fully boiled settled soaps. Palm kernel oil may be
+substituted for cocoanut oil in all cases.
+
+
+TALLOW BASE.
+
+    Tallow                       75-90 parts
+    Cocoanut oil                 25-10 parts
+
+
+PALM BASE.
+
+    Bleached Lagos palm oil      75-80 parts
+    Cocoanut oil                 25-20 parts
+
+                or
+
+    Tallow                          30 parts
+    Palm oil                        60 parts
+    Cocoanut oil                    10 parts
+
+
+OLIVE OIL BASE (WHITE).
+
+    Olive oil                    75-90 parts
+    Cocoanut oil                 25-10 parts
+
+                  or
+
+    Olive oil                    40 parts
+    Tallow                       40 parts
+    Cocoanut                     20 parts
+
+Where a green olive oil base is desired, olive oil foots are substituted
+for the olive oil. Peanut oil may replace the olive oil or part of it,
+the same being true of sesame oil and poppy seed oil.
+
+
+PALM AND OLIVE BASE.
+
+    Palm oil                     50 parts
+    Olive oil                    30 parts
+    Cocoanut oil                 20 parts
+
+                  or
+
+    Palm oil                     20 parts
+    Olive oil                    10 parts
+    Tallow                       50 parts
+    Cocoanut oil                 20 parts
+
+
+CHEAPER TOILET SOAPS.
+
+It is often necessary to manufacture a cheaper grade of soap for toilet
+purposes to meet the demand of a certain class of trade as well as for
+export. To accomplish this it is of course necessary to produce a very
+inferior product and run down the percentage of fatty acids contained in
+the soaps by the addition of fillers or to use cheaper oils in
+manufacturing. The most simple method of filling a soap is to load it at
+the mill with some substance much less expensive than the soap itself.
+Many of the cheaper toilet soaps, however, are not milled and it is,
+therefore, necessary to follow out some other procedure.
+
+Milled soaps, as has just been stated, are loaded at the mill. The
+consumers of cheaper toilet soaps in this country are accustomed to a
+milled soap and this grade of soap for home consumption is very often
+filled with numerous substances, but most generally by adding starch
+and talc. The addition of such materials of course later exhibit
+themselves by imparting to the cake of soap a dead appearance. Talc is
+more readily detected in the soap than starch by washing with it, as
+talc is insoluble and imparts a roughness to the soap, like sand or
+pumice, as the soap wears down. It may readily be added to 20 per cent.
+by weight. Starch is to be preferred to talc, in loading a soap, as it
+is not so readily noticeable in washing. It leaves the cake itself
+absolutely smooth although the lather formed is more shiny. This
+substance may be employed to as high a percentage as one-third the
+weight of the soap. It is, of course, possible to cheapen the best soap
+base by this method and the price may be further lowered by using the
+less expensive oils and fats to make the soap base.
+
+
+RUN AND GLUED UP SOAPS.
+
+A very cheap grade of soap may be made by making a run soap and adding
+the filler e. g. sodium silicate in the kettle during saponification.
+The percentage of fatty acids may be brought down to 10 per cent.,
+although of course a soap of this type shrinks a whole lot upon
+exposure.
+
+In making a "glued up" soap the procedure is the same for making the
+soap itself as with a settled soap, except that the soap is finished
+"curd" and later filled in the crutcher. The percentage of fatty acids
+in a soap of this type is seldom below 50 per cent.
+
+The method of "gluing up" a soap is best illustrated by a typical soap
+of this character in which the kettle is charged with the following
+stock.
+
+    Bleached palm oil                          5 parts
+    Distilled grease                           2   "
+    Cotton oil foots stock, 63% fatty acid     1   "
+    Rosin                                      4   "
+
+The palm oil is first run into the kettle, saponified and washed to
+extract any glycerine, then the rest of the fats and finally the rosin.
+The soap is then finished and settled as with a boiled settled soap. To
+assure success it is absolutely necessary that the soap settle as long a
+period as possible, or until the temperature is about 150 degs. F. The
+ideal temperature for carrying out the "gluing up" process is 140 degs.
+F., as at a lower temperature than this the soap is liable to cool too
+quickly and not be thoroughly glued up. A higher temperature than 150
+degs. F. causes delay in that the soap does not properly take the filler
+at a higher temperature and the soap must be kept in the crutcher until
+the temperature drops to the right point.
+
+The soap is run into the crutcher and the percentage of fatty acids run
+down to 50-55 per cent. with one of the following mixtures:
+
+    Sodium silicate, 59-1/2° B.     1 part
+    Potassium carbonate, 51° B.     1  "
+
+                    or
+
+    Sodium silicate, 59-1/2° B.     1 part
+    Potassium carbonate, 51° B.     1  "
+    Sodium sulfate, 28° B.          1  "
+
+From 230 to 300 pounds of either of these mixtures are required for a
+crutcher holding 2,600 pounds of soap.
+
+The crutching is continued until the mass is well "spiked," that is to
+say, a freshly broken surface of the soap, as the crutcher blade is
+jerked away, stands up like shattered sheets in triangular form
+[Transcriber's note: three triangles]), which retain their shape
+perfectly. When this condition is realized the soap is run into frames
+which are carefully crutched by hand to remove any air spaces. The
+surface of the soap is then smoothed down and heaped up in the center.
+After standing a day to contract, the surface is again leveled and a
+snugly-fitting board placed on the top of the soap upon which a weight
+is placed or upon which the workman treads and stamps until the surface
+is flat, thus assuring the further removal of air spaces. The soap
+remains in the frame from six to eight days and is then slabbed, barred
+and pressed by the usual method employed for soaps thus handled without
+milling.
+
+In a soap of this nature no hard and fast rule can be laid down as to
+the quantity of solution to be used for "gluing up" or the strength of
+the solution. In a soap of the type described the most satisfactory
+appearing cake will be obtained from a soap containing 58 per cent.
+fatty acids. That is to say, about 8 per cent. to 10 per cent. filling
+solution is added per hundred pounds of soap. The filling solutions
+given are very satisfactory. Carbonate of soda should be avoided in
+connection with sodium silicate as the property of efflorescing on the
+surface of the finished cake after a short time will prove detrimental.
+To assure successful gluing up it is advisable to experiment upon a
+small scale to determine the exact extent to which the filling solution
+should be diluted. Various proportions of water are added to a certain
+quantity of the filled soap. After the soap has been filled in a small
+receptacle a sample is taken and rubbed between the fingers. If the
+freshly exposed surface is smooth and glossy, the filling solution is
+weak enough, if rough it is too strong. It is of course understood that
+the temperature must be correct, 140 degs. to 150 degs. F., or the soap
+will be rough. By this means the operator can readily judge the correct
+strength of his filling solution. When properly carried out a perfectly
+satisfactory soap is obtained.
+
+
+CURD SOAP.
+
+The object of a soap which is finished "curd" or grained, is to obtain a
+harder piece of goods from low titer fat or to increase the percentage
+of fatty acids in the finished soap. This is still another method of
+producing a cheap grade of soap as by its adoption the cheaper oils and
+fats may be used to obtain a firm piece of soap.
+
+A typical charge for curd soap is:
+
+    Red oil        63 parts
+    Tallow         10  "
+    Rosin          27  "
+
+Cotton seed foots may be employed in place of red oil and a tallow of
+too high titer is not suitable for this kind of soap.
+
+The red oil and tallow are first saponified with 15 degs. B. lye, boiler
+pressure 80-90 pounds, 18 degs. B. lye for lower steam pressure, and two
+washings given to extract the glycerine. The rosin is added at the
+strengthening change and at the finish the soap is "pitched," that is to
+say, the soap is settled over night only. The next day the lyes are
+drawn off and a portion of the nigre pumped to another kettle which
+prevents later streaking of the soap. The soap is then boiled with 18
+degs. B. lye as with another strengthening change under closed steam.
+Salt brine or "pickle," 15 degs. B. is then added and the mass boiled
+with closed steam until the brine reaches a density of 18 degs. B. and
+the kettle pumped the next day. A soap of this type requires either hand
+or power crutching to assure homogeneity and prevention of streaks. To
+obviate any air spaces it is advisable to place over the top of the
+frame a tightly-fitted board which is heavily weighted down. This soap
+is also pressed without any milling.
+
+
+COLD MADE TOILET SOAPS.
+
+Comparatively little toilet soap is made by the cold or semi-boiled
+processes. While these are the simplest methods of manufacturing soaps
+the drawbacks of using them are numerous and only in a few cases are
+they very extensively employed. To make a toilet soap by the cold
+process a combination of good grade tallow and cocoanut oil is required.
+It requires 50 per cent. by weight of 36 degs. B. lye to saponify a
+given weight of tallow and 50 per cent. of 38 degs. B. lye for cocoanut
+oil. The lyes are used full strength or may be reduced slightly with
+water and the method of procedure is the same as already given in the
+general directions for cold made soaps.
+
+Cold made soaps are readily filled with sodium silicate which is added
+at the same time the stock is put into the crutcher. In adding the
+silicate it is necessary to add additional lye to that required for
+saponifying the fats, about 20 per cent. of 36 degs. B. lye is the
+proper amount. There is of course a certain amount of shrinking due to
+the addition of this filler and the finished cake is exceedingly hard,
+yet the author has seen a good looking cake of cheap soap made from as
+high a proportion as 420 parts of tallow to 600 parts of silicate.
+
+Cold made soaps are usually pressed without milling, although it is
+readily feasible to mill a cold made soap provided it is not a filled
+soap such as has just been described.
+
+
+PERFUMING AND COLORING TOILET SOAPS.
+
+Equally important as the soap itself or even to a greater extent is the
+perfume of a toilet soap. A prominent manufacturer recently made the
+statement, which is often the truth, that it makes no difference to the
+public what kind of soap you give them, as long as you put plenty of
+odor into it. The perfuming of soaps is an art in itself and a subject
+to be treated by one versed in this particular branch. We can only take
+into account the importance of the perfume as related to toilet soap
+not only, but the necessity of adding a certain proportion of the
+cheaper products of odoriferous nature to laundry soap to cover and
+disguise the odor of even this type of soap.
+
+The price of a cake of toilet soap to a great extent depends upon the
+perfume, and the manufacturer should aim to give the best possible
+perfume for a certain price. He should not allow his personal likes or
+dislikes to enter into the judgment of whether an odor is good or not,
+but submit it to a number of persons to obtain the concensus of opinion.
+In giving or selling a piece of soap to the consumer, it is second
+nature for him to smell it, and in the great majority of cases his
+opinion is formed not from any quality the soap itself may have during
+use, but from the odor. This only emphasizes the fact that the perfume
+must be pleasing, not to one person, but to the majority, and many
+brands owe their popularity to nothing more than the enticing perfume.
+
+Perfuming of soap is closely allied to the soap making industry, but as
+stated a branch in itself. It is, therefore, not our purpose to give
+numerous formulae of how to perfume a soap, but rather to advise to go
+for information to some one who thoroughly understands the
+characteristics of the numerous essential oils and synthetics and give
+positive information for the particular odor desired. Under no
+circumstances is it advisable to purchase a perfume already compounded,
+but since all perfumes are a blend of several or many essential oils and
+synthetics, it is a more positive assurance of obtaining what is
+desired, by purchasing the straight oils and blending or mixing them as
+one desires.
+
+The perfume is added to a milled soap just before the milling process in
+the proper proportion per hundred pounds of soap. In cold made or
+unmilled soaps it is added in the crutcher while the soap is still hot.
+By this method, of course, a proportion of the perfume is lost due to
+its being more or less volatile.
+
+
+COLORING SOAP.
+
+While much toilet soap is white or natural in color, many soaps are also
+artificially colored. The soap colors used for this purpose are mostly
+aniline dyestuffs. The price of these dyestuffs is no criterion as to
+their quality, as the price is usually regulated by the addition of some
+inert, water soluble substance like common salt or sugar.
+
+The main properties that a dyestuff suitable for producing a colored
+soap should have are fastness to light and to alkali. They should
+further be of such a type that the color does not come off and stain a
+wash cloth or the hands when the soap is used and should be soluble in
+water. Under no circumstances is it advisable to add these in such a
+quantity that the lather produced in the soap is colored. It is
+customary to first dissolve the dye in hot water as a standardized
+solution. This can then be measured out in a graduate and added to the
+soap the same time as the perfume is put in. About one part of color to
+fifty parts of water is the proper proportion to obtain a perfect
+solution, though this is by no means fixed. In making up a solution thus
+it is an improvement to add to the same about one-half of one per cent.
+of an alkali either as the hydroxide or carbonate. Then, if there is any
+possibility of change of color due to alkalinity of the soap, it will
+exhibit itself before the color is added.
+
+A particularly difficult shade to obtain is a purple, as there is up to
+the present time no purplish aniline color known which is fast to light.
+Very good results in soap may be obtained by mixing a fast blue, as
+ultramarine or cobalt blue, with a red as rhodamine or eosine.
+
+Inasmuch as the colors for soap have been carefully tested by most of
+the dyestuff manufacturers, and their information, usually reliable, is
+open to any one desiring to know about a color for soap, it is better to
+depend upon their experience with colors after having satisfied one's
+self that a color is what it is represented for a particular shade, than
+to experiment with the numerous colors one's self.
+
+
+MEDICINAL SOAPS.
+
+Soap is often used for the conveyance of various medicants, antiseptics
+or other material presumably beneficial for treatment of skin diseases.
+While soap is an ideal medium for the carrying of such materials, it is
+an unfortunate condition that when incorporated with the soap, all but a
+very few of the numerous substances thus employed lose their medicinal
+properties and effectiveness for curing skin disorders, as well as any
+antiseptic value the substance may have. Soap is of such a nature
+chemically that many of the substances used for skin troubles are either
+entirely decomposed or altered to such an extent so as to impair their
+therapeutic value. Thus many of the claims made for various medicated
+soaps fall flat, and really have no more antiseptic or therapeutic merit
+than ordinary soap which in itself has certain germicidal and cleaning
+value.
+
+In medicating a soap the material used for this purpose is usually added
+at the mill. A tallow and cocoanut oil base is best adapted for a soap
+of this type. The public have been educated more or less to the use of
+colored soap to accentuate its medicinal value, and green is undoubtedly
+the most popular shade. This inference, however, is by no means true for
+all soaps of this character. Possibly the best method of arranging
+these soaps is briefly to outline some medicinal soaps.
+
+
+SULPHUR SOAPS.
+
+The best known sulphur soaps contain anywhere from one to 20 per cent.
+of flowers of sulphur. Other soaps contain either organic or inorganic
+sulphur compounds.
+
+
+TAR SOAP.
+
+The tar used in the manufacturing of tar soap is obtained by the
+destructive distillation of wood, the pine tar being the most
+extensively employed. While the different wood tars contain numerous
+aromatic compounds, such as phenols, phenyl oxides, terpenes and organic
+acids, these are present in such a slight proportion so as to render
+their effectiveness practically useless. It has, therefore, been tried
+to use these various compounds contained in the tar themselves to make
+tar soap really effective, yet tar is so cheap a substance that it is
+usually the substance used for medicating a tar soap. About 10 per cent.
+of tar is usually added to the soap with 2 ounces of lamp black per
+hundred pounds of soap.
+
+
+SOAPS CONTAINING PHENOLS.
+
+Phenol (Carbolic Acid) is most extensively used in soaps of this kind,
+which are called carbolic soaps. Carbolic soaps are generally colored
+green and contain from 1 to 5 per cent. phenol crystals.
+
+The cresols are also extensively used for making soaps named carbolic.
+These substances impart more odor to the soap and really have more
+disinfecting powers than phenol when incorporated with soap.
+
+Other soaps, containing the phenol group, which are well known are
+resorcinol soap, salol soap, thymol soap, naphthol soap, etc. From one
+to five per cent of the compound after which the soap is named is
+usually incorporated with the soap.
+
+
+PEROXIDE SOAP.
+
+Hydrogen peroxide in itself is an excellent disinfectant. It loses all
+its medicinal value, however, when added to the soap. To overcome this
+objection various metallic peroxides are added to the soap, as sodium
+peroxide, zinc peroxide and barium peroxide. These generate hydrogen
+peroxide by the addition of water. Sodium perborate is also used in
+peroxide soaps, as this substance is decomposed by water into hydrogen
+peroxide and sodium metaborate.
+
+
+MERCURY SOAPS.
+
+Mercuric chloride (corrosive sublimate) is most extensively used for the
+production of mercury soaps. Because of its extremely poisonous
+properties care should be taken in using it. Since it really eventually
+loses any antiseptic value in the soap through forming an insoluble
+mercury soap it might better be omitted entirely.
+
+
+LESS IMPORTANT MEDICINAL SOAPS.
+
+While the above mentioned soaps are probably the best known medicated
+soaps, there are numerous other soaps which may be classed under these
+kinds of soaps. Thus we have cold cream soap, which can be made by
+adding Russian Mineral Oil, 1 to 5 per cent., to the soap; witch hazel
+soap, made by the addition of extract of witch hazel; iodine soap, made
+by adding iodine or iodoform; formaldehyde soap, made by adding
+formaldehyde; tannin soaps, made by adding tannin. In fact, there have
+been incorporated in soap so great a number of substances that the list
+might be greatly enlarged.
+
+Medicated soaps are not only used in solid form, but in powder, paste
+and liquid soap as well. The only difference in a soap like those just
+referred to is that the medicant is incorporated with these forms of
+soaps as convenience directs.
+
+
+CASTILE SOAP.
+
+A pure castile soap should be made from olive oil. This, however, is not
+always the case, as a number of oils as well as tallow are used to
+adulterate this oil to cheapen it, and there are even some soaps called
+castile which contain no olive oil at all. Most of the pure castile soap
+used in this country is imported, as it is a difficult matter for the
+American manufacturer to compete with the pure imported castile soap,
+since both labor and oil itself are so much cheaper in the vicinities of
+Europe where this oil is produced, that this advantage is more than
+compensated by the carrying and custom charges by importing the castile
+soap.
+
+Castile soap may be made either by the full boiled or cold process.
+There are numerous grades of olive oil, and those used for soap making
+are denatured to lower the duty charges. Olive oil makes a hard white
+soap, usually sold in bars, and olive oil foots a green soap, due to the
+coloring matter contained in this oil.
+
+To make a boiled castile soap, a composition of 10 per cent. Cochin
+cocoanut oil and 90 per cent. olive oil may be used. To cheapen this,
+peanut oil (Arachis oil) may entirely replace the olive oil, or about 20
+per cent. of corn or soya bean oil may be added. The oils are saponified
+as usual in making a settled soap and to prevent rancidity the soap is
+boiled near the finish for some time in the closed state with
+sufficient excess of alkali to give it a sharp taste, then grained with
+lye, the lye drawn off, closed with water and then grained with salt.
+This process is repeated until the desired strength is reached. The last
+graining should not be too great, and on the last change the soap should
+not be thinned out, as it will contain too great a quantity of water
+when slabbed.
+
+In making a cold castile soap the usual method is pursued as already
+directed under cold made soap. When the soap is taken from the crutcher
+it is advisable, however, to keep the soap in the frame well covered to
+assure complete saponification. Some manufacturers use very small frames
+which are placed into compartments, well insulated to retain heat.
+Several formulae for cold made castile soaps, follow. It may be noted
+that some of these contain practically no olive oil.
+
+                 I
+
+    Olive oil                        2030
+    Palm kernel                       674
+    Soda lye, 35 per cent. B.        1506
+
+                 II
+
+    Olive oil                        2030
+    Cochin cocoanut oil               674
+    Soda lye, 36 per cent. B.        1523
+    Sodium Silicate                    82
+
+                 III
+
+    Palm kernel oil                  1578
+    Tallow                            940
+    Olive oil                           7
+    Sodium silicate, 20 per cent.     190
+    Soda lye, 36 per cent. B.        1507
+
+                 IV
+
+    Olive oil (yellow)               1000
+    Soda lye, 37 per cent. B.         500
+
+                 V
+
+    Olive oil                          90
+                   or
+    Palm kernel            }           10
+    Cochin or cocoanut oil }           10
+    Lye, 37 per cent. B.               51
+
+If any of the soaps containing a high proportion of cocoanut oil are
+boiled the soap will float. It is therefore necessary to keep the
+temperature as low as possible.
+
+
+ESCHWEGER SOAP (BLUE MOTTLED).
+
+Eschweger soap is a colored mottled or marbled soap made to a very
+slight extent in this country. Inasmuch as it has been introduced to the
+export trade, it is made for this purpose by some manufacturers. A high
+percentage of cocoanut oil is usually used together with tallow and
+grease. About one-third of each is a typical formula. In a soap of this
+character the fact that cocoanut oil soap takes up a large quantity of
+water and salts of various kinds and is difficult to salt out is made
+use of. The tallow and grease are first saponified as usual, then the
+cocoanut oil is pumped and saponified. When the saponification is nearly
+completed either silicate or carbonate of soda or common salt are added
+to make the soap "short" so as to form the mottle. The finishing of a
+soap of this type can only be gained by practice and it is rather
+difficult to explain the exact appearance of the kettle at this stage.
+The surface of the soap should be bright and lustrous with the steam
+escaping in numerous places in rose-like formation. A sample on the
+trowel should have a slight sharpness to the tongue and be plastic. When
+the soap slides from the trowel it should break short. When the soap has
+reached this stage the desired coloring matter, usually ultramarine, is
+added to the soap either in the kettle or crutcher and the soap framed.
+The yield is 200-215 pounds per hundred pounds of stock.
+
+Several modifications of this general method for Eschweger soap are used
+by adopting the half boiled or cold process.
+
+
+TRANSPARENT SOAP.
+
+Transparent soap is really not a most desirable soap for toilet
+purposes, as it contains an excess of free alkali. It has, nevertheless,
+met with public approval because of the fact it is novel in being
+transparent. Except for this fact very little merit can be claimed for a
+soap of this kind.
+
+The transparency of soap is generally due to the presence of alcohol,
+sugar or glycerine in the soap when it is made. It is very essential in
+a soap of this character, where lightness and clearness of color are
+desired, that the material for making the soap be carefully selected as
+to color and purity. The perfumes also play an important part in the
+color of the soap and many of the tinctures, balsams and infusions used
+in perfuming soap may eventually cause trouble by spotting. If the soap
+is artificially colored, which is almost always the case, the dyestuffs
+used for this purpose should have careful attention and only those
+should be used which are known to resist the action of alkalis. Where
+rosin is used this product must be of the better grade. Distilled water
+is always preferable for use in transparent soap. The government permits
+the use of a specially denatured alcohol. This alcohol is not taxed and
+consists of grain (ethyl) alcohol denatured with 5 per cent. wood
+(methyl) alcohol. Some soapmakers prefer to use a more expensive refined
+methyl alcohol, but outside of adding to the cost of the soap, there is
+no particular advantage. The glycerine should be chemically pure. As to
+the oils and fats these should be low in acid and of good color. Under
+no circumstances should the crutcher or kettle in which the soap is made
+be rusty or unclean in any way. For a light soap enameled utensils are
+to be preferred.
+
+To obtain transparency in soap the following general methods may be
+given.
+
+1. Where the transparency is due to sugar.
+
+2. Where alcohol and glycerine produce transparency.
+
+3. Where (1) or (2) is supplemented by the use of castor oil.
+
+4. Where transparency depends upon the percentage of fatty acid in a
+soap and the number of times the soap is milled.
+
+Under the first method at least 25 per cent. of the charge should be
+cocoanut oil, the other constituent being tallow or any fat or oil
+capable of giving a sufficiently hard soap. The soap is boiled and
+finished as usual, then run to the crutcher to be mixed with a strong
+cane sugar solution, containing 10-20 per cent. sugar of the weight of
+the soap. The sugar is dissolved in its own weight of water and the
+solution heated to 175 degs. F. before being very slowly added to the
+soap. As the water evaporates, soaps of this type show spots due to the
+sugar thus being thrown out of solution.
+
+Transparent soap made under the second method may be saponified as usual
+and consist of any good toilet base. The soap is run to the crutcher and
+mixed with 95 per cent. alcohol in the proportion of one part alcohol to
+two parts of fatty acid contained in the soap together with glycerine in
+the same proportion.
+
+By the third method castor oil alone may be used to make the soap or
+added to any of the above bases up to 33-1/3 per cent. of the charge. If
+castor oil only is used, but 2 per cent. or 3 per cent. of sugar is
+required.
+
+In the last method a combination of 80 per cent. tallow, very low in
+free acid, 20 per cent. cocoanut oil and 5 per cent. W. W. rosin is a
+suitable charge. The saponification and finishing is carried out as with
+a full boiled soap. The soap is then placed into a jacketed vessel,
+provided with dry-steam coils, by which the excess water is evaporated
+from the soap until it contains 73 per cent. fatty acids. When the thick
+mass reaches this stage it is framed and when cool is suitable for
+obtaining a semi transparency which now depends upon the number of times
+the soap is milled, it being, of course, inferred that no solid matter
+of any sort be added to the soap.
+
+
+COLD MADE TRANSPARENT SOAP.
+
+While transparent soaps may be made by the above general methods they
+are usually made by the semi-boiled or cold process. By this process a
+more satisfactory soap is obtained and it is more simple to carry out. A
+detailed description of this method is best and most easily given by
+using a typical formula.
+
+    Charge:
+
+      Tallow                       193-1/2 lbs.
+      Cochin Cocoanut Oil          169-1/2 "
+      Castor Oil                    89-1/2 "
+      Soda Ash                       7-3/4 "
+      Soda Lye, 36 degs. B.        256     "
+      Sugar (Cane)                 198     "
+      Alcohol                      126     "
+      Water (Distilled)             80     "
+
+To proceed, first place into a crutcher or jacketed kettle the oils and
+fat and heat to 140 degs. F. Then add the soda ash dissolved in about 30
+pounds of the water, after which the lye is added and the mass stirred
+until a finger or stick run over the surface leaves an imprint. Where
+the soap has reached this stage, it is well covered and allowed to stand
+about two hours or until it bulges in the center, after which the rest
+of the water which should contain no lime or other mineral substance and
+which is preferably distilled water, is added. The sugar is then slowly
+shoveled in while the mass is stirring and finally the alcohol is poured
+in. The heat is then increased to 160 degs. F. by dry steam and the soap
+crutched until dissolved. Under no circumstances should any soap be
+allowed to remain above the surface of the mass on the sides of the
+mixer. This crutching operation consumes about one hour, and when
+finished the soap should stand in the vessel about half an hour when a
+small sample is taken out to cool. This sample should be clear and show
+an excess of alkali. If it is not clear more alcohol is added, if not of
+sufficient strength more lye put in until the desired condition is
+reached. The perfume and color are now added.
+
+The soap is then framed and allowed to set after which it is cut,
+allowed to dry slightly and then pressed. To obtain a polished cake
+transparent soaps are often planed before pressing and after pressing
+polished with a soft cloth, dampened with alcohol. Instead of framing
+this soap, it is sometimes "tubed," that is to say, the soap from the
+crutcher is run into specially constructed tubes of a shape near that of
+the desired cake and allowed to cool, after which it is cut and pressed.
+All scraps are returned to the crutcher, but in so doing the soap is
+slightly darkened in color. It is advisable to expose a finished cake of
+transparent soap to the air for some time as by so doing it becomes
+clearer.
+
+Other formulae for cold made transparent soaps made as just outlined
+follow:
+
+                      I.
+    Bleached Tallow                134 lbs.
+    Cochin Cocoanut Oil             88  "
+    Castor Oil                      20  "
+    W. W. Rosin                      7  "
+    Cane Sugar                      64  "
+    Water                           32  "
+    Glycerine                       34  "
+    Soda Lye, 38 degs. B.          135  "
+    Alcohol                         16 gal.
+
+                     II.
+    Tallow                         211   lbs.
+    Cochin Cocoanut Oil            185     "
+    Castor Oil                      97-1/2 "
+    Soda Ash                         8-1/2 "
+    Water                          106     "
+    Soda Lye, 38 degs. B.          279     "
+    Sugar                          216     "
+    Alcohol                        137     "
+
+                     III.
+    Castor Oil                      60    lbs.
+    Cochin Cocoanut Oil            195     "
+    Tallow                         120     "
+    Alcohol                        115     "
+    Sugar                           90     "
+    Water                           53     "
+    Glycerine                       53     "
+    Soda Lye, 38 degs. B.          205-1/2 "
+
+                     IV.
+    Tallow                         100 lbs.
+    Cochin Cocoanut Oil            100  "
+    Castor Oil                      60  "
+    Glycerine                       20  "
+    Rosin, W. W.                    20  "
+    Sugar                           40  "
+    Water                           50  "
+    Soda Lye, 36 degs. B.          164  "
+    Alcohol                          8 gal.
+
+                      V.
+    Tallow                         174 lbs.
+    Cocoanut Oil                   114  "
+    Soda Lye, 38 degs. B.          170  "
+    Sugar                           80  "
+    Water                           72  "
+    Alcohol                         16 gal.
+
+Rosin may be added in this formula up to 20 per cent. of fats used and
+the tallow cut down correspondingly.
+
+
+SHAVING SOAPS.
+
+The requirements of a shaving soap are somewhat different than those of
+other soaps. To be a good shaving soap the lather produced therefrom
+must be heavy, creamy, but not gummy, and remain moist when formed on
+the face. The soap itself should be of a soft consistency so as to
+readily adhere to the face when used in stick form. It should
+furthermore be neutral or nearly so to prevent the alkali from smarting
+during shaving.
+
+Shaving soap is made in the form of a stick, and a tablet for use in the
+shaving mug. Some shavers prefer to have the soap as a powder or cream,
+which are claimed to be more convenient methods of shaving. While a
+liquid shaving soap is not as well known because it has not yet become
+popular, some soap for shaving is made in this form.
+
+Formerly shaving soap was extensively made from a charge of about 80
+parts tallow and 20 parts cocoanut oil as a boiled settled soap, but
+either making the strengthening change with potash lye or using potash
+lye in saponifying the stock and graining with salt. Soaps for shaving
+made in this manner are very unsatisfactory, as they do not produce a
+sufficiently thick or lasting lather and discolor very materially upon
+ageing. Potassium stearate forms an ideal lather for shaving, but
+readily hardens and hence needs some of the softer oils, or glycerine
+incorporated with it to form a satisfactory soap for shaving.
+
+The selection of materials for making a shaving soap is important. The
+tallow used should be white and of high titer. Cochin cocoanut oil is to
+be preferred to the other kinds, and the alkalis should be the best for
+technical use that can be purchased--76 per cent. caustic soda and 88-92
+per cent. caustic potash are suitable. By the use of stearic acid it is
+a simple matter to reach the neutral point which can be carefully
+approximated.
+
+The following are shaving soap formulae which have been found to give
+good satisfaction:
+
+                      I.       lbs.
+    Tallow                         360
+    Stearic acid                    40
+    Soda lye, 41° B.               147
+    Potash lye, 34° B.              87
+    Water                           32
+    Gum tragacanth                   1
+
+                     II.       lbs.
+    Tallow                         282
+    Cocoanut oil                    60
+    Stearic acid                    50
+    Bayberry wax                    18
+    Soda lye, 41° B.               147
+    Potash lye, 34° B.              90
+    Water                           32
+
+                     III.      lbs.
+    Tallow                         400
+    Cocoanut oil                   176
+    Stearic acid                   415
+    Caustic soda, 40° B.           182
+    Caustic potash, 38° B.         108
+
+To proceed, first run into the crutcher the tallow, cocoanut oil and
+bayberry wax when used, and bring the temperature of the mass up to
+140°-160° F. by dry steam. Then add the caustic soda lye and keep on
+heat with occasional mixing until it is all taken up. When this stage is
+reached gradually add all but about 5 per cent. of the potash lye, and
+complete the saponification. This point having been reached, the heat is
+turned off; the crutcher is run and the stearic acid, previously melted
+by dry steam in a lead-lined or enameled vessel, is run in in a
+continuous stream and the crutching continued for fifteen minutes to
+half an hour. Samples are taken at this time, cooled and tested by
+alcoholic phenolphthalein solution. If too alkaline more stearic acid is
+added, if too acid more potash lye from that previously reserved. After
+each addition of lye or stearic acid the mass is crutched from 10 to 15
+minutes longer, another sample is taken, cooled and again tested. When
+the phenolphthalein shows a very light pink after several minutes, the
+soap is practically neutral, although at this point one can better judge
+by dissolving a sample in hot neutralized alcohol made by putting into
+the alcohol a few drops of phenolphthalein, and then adding weak alkali
+drop by drop from a burette until a slight pink, not yellow, tint is
+obtained, and noting the color of the solution. The solution should show
+a very light pink when the soap is properly neutralized. When this stage
+is arrived at the gum tragacanth, previously softened in water, is
+crutched in if it is to be added. The soap is then framed, stripped in
+three or four days, dried and milled.
+
+The formulae as given are for shaving sticks, and do not readily press
+unless thoroughly dried. A more satisfactory result is obtained by
+adding at the mill 25 per cent. of white tallow base to obtain a
+satisfactory mug soap.
+
+
+SHAVING POWDER.
+
+Shaving powder differs from the soaps just described in being
+pulverized, usually adding up to 5 per cent. starch to prevent caking.
+Any of the above soaps, dried bone dry, with or without the addition of
+tallow base make a satisfactory powder for shaving.
+
+
+SHAVING CREAM.
+
+Shaving cream is now a very popular shaving medium due to the rapidity
+and convenience with which one can shave by the use of this product.
+Formerly shaving cream was made from the liquid oils like olive oil and
+a soft fat like lard, together with cocoanut oil. Now, however, most of
+the popular shaving creams are made from stearic acid and cocoanut oil,
+as a far superior product is obtained by the use of these substances. By
+using these a more satisfactory cream is obtained, and it is far more
+convenient to make. The lather also produced therefrom is more suitable
+for shaving, being thick, creamy and remaining moist.
+
+A few typical formulae for shaving creams of this type are as follows:
+
+                          I.       lbs.
+    Cochin cocoanut oil             26
+    Stearic acid                   165
+    Caustic potash lye, 50° B.      69
+    Glycerine C. P.                 76
+    Water                           38
+
+                          II.      lbs.
+    Cochin cocoanut oil             18
+    Stearic acid                    73
+    Caustic potash lye, 39° B.      54
+    Glycerine                       33
+    Water                           27
+
+                         III.      lbs.
+    Cochin cocoanut oil             18
+    Stearic acid                    73
+    Caustic potash lye, 39° B.      54
+    Glycerine                       20
+    Water                           40
+
+                         and       lbs.
+
+    Stearic acid                    60
+    Glycerine C. P.                 85
+    Water                          165
+    Sodium carbonate                50
+    Borax                            1
+
+To make a shaving cream by Formula I or II, the cocoanut oil and
+glycerine are first put into a suitable mixing apparatus or crutcher,
+and heated to 120° F. A part or all the potash lye is then added and the
+cocoanut oil saponified. The rest of the potash lye and the water are
+then added, and with the mixer running the stearic acid, previously
+melted in a lead-lined or enameled vessel, is then poured in in a stream
+and the mass stirred until smooth, care being exercised not to aerate it
+too much. The cream is then tested for alkalinity, the best method being
+by that described under shaving soap, in which the sample is dissolved
+in alcohol. Because of the large quantity of water present,
+phenolphthalein is unsatisfactory, as dissociation of the soap may show
+a pink indication in spite of the fact the mass is on the acid side. For
+a quick method of testing the bite on the tongue is a satisfactory
+criterion. If a cooled sample bites the tongue more stearic acid is
+added until there is a 3% excess of this. When the proper neutralization
+has taken place the cream is perfumed and framed in a special frame, or
+it may be allowed to cool in the mixer and perfumed the next day. When
+cool the cream is strained, or put through an ointment mill, after which
+it is ready to fill into tubes.
+
+The procedure for the first part of Formula III is the same as that just
+given. The second part of the formula is made the same as a vanishing
+cream for toilet purposes. To make this, first melt the stearic acid as
+already directed. Dissolve the sodium carbonate and borax in water and
+when dissolved add the glycerine and stir. Then heat this solution to
+about 100°-120° F. and while stirring in a suitable mixing machine into
+which this solution has been poured after being heated, or better still
+in which it has been heated by dry steam, add the stearic acid. Continue
+mixing until smooth and then allow to cool, or run into frames to cool.
+
+When the shaving cream and vanishing cream are both cool, they are mixed
+in the proportion of one of the former to two of the latter. It is
+claimed that in thus making a shaving cream a smoother product is
+obtained, although it may be said that the vanishing cream is merely a
+soft soap and the ultimate result is the same as though the various
+ingredients were added in one operation, rather than making two separate
+products and then mixing them, thereby considerably increasing the cost
+of manufacture.
+
+
+PUMICE OR SAND SOAPS.
+
+Pumice and sand are at times added to soap to aid in the removal of dirt
+in cleansing the hands. In some cases these soaps are made in the form
+of a cake, in others they are sold in cans in the form of a paste.
+
+A hand paste is usually made by merely dissolving ordinary tallow base
+in two or three times its weight of hot water and mixing in the desired
+quantity of pumice or sand and in some instances adding a little
+glycerine to keep it soft or a solvent of some kind for grease. It may
+also be made by directly incorporating any of these in a potash soap.
+
+A cold made or semi-boiled cocoanut or palm kernel oil soap is the base
+used to add the pumice or sand to in making a cake soap of this sort.
+The following formulae serve as a guide for these soaps.
+
+                       I.
+
+    Palm Kernel or Ceylon Cocoanut Oil      705 lbs.
+    Pumice (Powdered)                       281 "
+    Soda Lye, 38° B.                        378 "
+
+                      II.
+
+    Cocoanut Oil                            100 "
+    Soda Lye, 38° B.                         55 "
+    Water                                     6 "
+    Silver Sand (fine)                       60 "
+
+To proceed place the oil in a crutcher and heat to 140° F. Sift in the
+pumice and mix thoroughly. The lye is then added which causes a curdling
+of the grain. The stirring is continued until the grain closes and the
+soap is smooth, after which the desired perfume is added and the soap
+dropped into a frame and crutched by hand. When the soap is set, it is
+slabbed, cut into cakes, dried slightly and pressed.
+
+
+LIQUID SOAPS.
+
+Liquid soaps are merely solutions of a potash soap, usually cocoanut oil
+soap, although corn oil is used to make a cheap soap. One of the
+difficulties encountered in liquid soap is to keep it clear. At a low
+temperature a sediment is often formed, but this can be overcome by the
+use of sugar and filtering the soap through a filter press at a low
+temperature. In order to prevent the soap from freezing, it is necessary
+to lower the freezing point by the addition of glycerine or alcohol.
+
+To make liquid soap by any of the formulae given below, the oil is first
+run into a jacketed kettle with a stirring device, and heated to about
+120° F. The potash lye is then added and the oil saponified. When the
+saponification takes place, especially when cocoanut oil is used, the
+mass swells rapidly and may foam over the sides of the kettle unless
+water is used to check this, or a kettle of about four to five times the
+capacity of the total charge of soap is used. When the saponification
+has occurred, the sugar, borax and glycerine are added, the water run in
+and the mixture stirred until the soap is thoroughly dissolved. Heat
+aids materially in dissolving the soap. The soap is then allowed to cool
+and if color or perfume is to be added this is stirred in, after which
+the soap is cooled and filtered or else run directly into barrels.
+
+Tallow is not suitable for making a clear liquid soap since it is too
+high in stearine which when formed into the stearate makes an opaque
+solution. The formulae herewith given have been found to give good
+practical results.
+
+                   I.               lbs.
+    Cocoanut oil                    130
+    Caustic potash lye, 28° B.      135
+    Sugar                            72
+    Borax                             2
+    Water                           267
+
+                  II.               lbs.
+    Corn oil                        130
+    Caustic potash lye, 26° B.      135
+    Sugar                            72
+    Borax                             2
+    Water                           267
+
+                  III.              lbs.
+    Cocoanut oil                    100
+    Caustic potash lye, 28° B.      102
+    Glycerine                       100
+    Sugar                            70
+    Water                           833
+
+Formulae I and II contain about 20 per cent. fatty acids. It is
+possible, of course, to either increase or decrease the percentage of
+fatty acid by varying the amount of water. The water used in making
+liquid soaps, of course, should be soft, for hard water forms insoluble
+soaps which precipitate and cause a sediment.
+
+
+USE OF HARDENED OILS IN TOILET SOAPS.
+
+While the introduction of the hydrogenation of oils is a decided advance
+in the production of suitable cheaper oils for soap making,
+comparatively little hardened oil is employed for soap making in America
+up to the present time. In Europe, however, considerable advance has
+been made by the use of such oils for manufacturing soap therefrom and a
+number of plants turn out large quantities of hydrogenated oils for soap
+making as well as for edible purposes. Recently a company has been
+formed in this country for hardening oils and it is very probable that
+the future will see this material extensively used in our own country,
+as these appear to be the one present hope of the soap manufacturer as a
+check on the ever increasing cost of fats and oils now used in making
+soap.
+
+It is an unfortunate condition that hydrogenated oils produced abroad
+are sold under names which give absolutely no indication as to the oil
+which has been hardened. The softer and cheaper oils like fish oil,
+linseed oil, cottonseed oil, etc., are generally hardened for soap
+manufacture to different degrees of hardness. While it is impossible to
+definitely state just what products as Candelite, Talgol, Krutolin or
+several other coined names of hardened oils are, various investigators
+have experimented with them as to their adaptability for producing
+toilet soaps and found that suitable toilet soaps may be made from them.
+While many objections were at first met with concerning soaps made from
+these products, as to their unsatisfactory saponification, the poor
+lathering quality of the soaps and their odor and consequent difficulty
+in perfuming, the results of most investigators along these lines
+indicate that these in many cases were due to prejudice against or
+unfamiliarity with handling oils of this type for soap making.
+
+In manufacturing soap from hardened oils it is usually necessary to
+incorporate with the charge lard, tallow, tallow oil or some other soft
+oil of this nature. Satisfactory bases for toilet soaps, made as boiled
+settled soap by the use of Talgol (undoubtedly hardened fish oil), are
+said to be made by the formulae[10] below.
+
+              I.
+
+    Tallow                  45 parts
+    Talgol                  40 "
+    Cocoanut Oil            15 "
+
+              II.
+
+    Cocoanut Oil (Ceylon)    6 "
+    Tallow                  12 "
+    Talgol, Extra           12 "
+
+The method of boiling a soap of this type does not differ materially
+from that of making settled tallow soap base. The soap itself has a
+different odor than a straight tallow base, but is said to make a very
+satisfactory soap for milling and to be of good appearance.
+
+Satisfactory transparent soaps are made from the hardened oil Candelite,
+which replaces the tallow in transparent soap formulae such as have
+already been given in the section under "Transparent Soaps." The method
+of manufacturing a soap by the use of this product varies in no way from
+the usual method employed for making these soaps.
+
+Since hydrogenated oils are high in stearine, their use in shaving soaps
+is a decided advantage. It has previously been pointed out that
+potassium stearate forms an ideal lather for shaving, and in the
+hydrogenating process the olein is converted to stearine. Thus a
+hardened oil is advantageous in a shaving soap. As an example of a cold
+made soap for shaving the following may be taken.[11]
+
+    Talgol Extra            50 lbs.
+    Cocoanut Oil            10 "
+    Lard                    10 "
+    Soda Lye, 38° B.        20 "
+    Potash Lye, 37° B.      21 "
+
+This soap may be made in a crutcher by the method generally used in
+making soap by the cold process.
+
+
+TEXTILE SOAPS.
+
+Soap is a very important product to every branch of the textile
+industry. For woolen fabrics it is used for scouring, fulling and
+throwing the wool; in the silk industry it is necessary for degumming
+the raw silk, as well as for dyeing; in the cotton mills it is used to
+finish cotton cloth and to some extent in bleaching; it is, furthermore,
+employed in a number of ways in the manufacture of linen. Large
+quantities of soap are thus consumed in an industry of so great an
+extent and the requirements necessitate different soaps for the
+different operations. We will, therefore, consider these in detail.
+
+
+SCOURING AND FULLING SOAPS FOR WOOL.
+
+The soaps used to scour wool and for fulling the woven cloth are usually
+made as cheaply as possible. They are, however, generally pure soaps, as
+filling material such as sodium silicate does not readily rinse out of
+the wool and if used at all must be added very sparingly. Both cold made
+and boiled settled soaps are made for this purpose. The soap is
+generally sold in barrels, hence is run directly to these from the
+crutcher or soap kettle. As cold made soaps the following serve for wool
+scouring or fulling.
+
+                 I.
+
+    Palm Oil                         200 lbs.
+    Bone Grease                      460 "
+    Soda Lye, 36° B.                 357 "
+    Water                            113 "
+    Soda Ash                          50 "
+    Citronella                         2 "
+
+                 II.
+
+    Palm Oil (Calabar, unbleached)   155 "
+    House Grease                     360 "
+    Soda Lye, 36° B.                 324 "
+    Water                            268 "
+    Sodium Silicate                   83 "
+
+                 III.
+
+    House Grease                     185 "
+    Palm Oil (unbleached)            309 "
+    Soda Lye, 36° B.                 309 "
+    Water                            391 "
+    Soda Ash                          70 "
+    Sodium Silicate                   60 "
+    Corn Starch                       10 "
+
+These soaps are made in a crutcher by the usual process for cold-made
+soaps, crutched until smooth, dropped into a barrel and crutched by hand
+the next day or just before cooling.
+
+As a settled soap for these operations the following charge is typical:
+
+    Palm Oil                                               34 parts
+    Cottonseed foots or its equivalent in fatty acids      33  "
+    Rosin                                                  10  "
+    House Grease                                           23  "
+
+The method of boiling such a soap is the same as for any settled soap up
+to the strengthening change. When this stage is reached, sufficient lye
+is added to strengthen the kettle strongly. It is then boiled down with
+closed steam on salt brine or "pickle" until a sample of the lye taken
+from the bottom stands at 16°-22° B. The soap is then run into barrels
+and after standing therein for a day is hand crutched until cool to
+prevent streaking of the soap.
+
+Besides a soap of this type a settled tallow chip soap is used.
+
+
+WOOL THROWER'S SOAP.
+
+Soaps for wool throwing are sometimes made from olive oil foots but
+these are often objected to because of the sulphur-like odor conveyed to
+the cloth due to the method by which this oil is extracted with carbon
+disulphide. A potash soap hardened somewhat with soda is also used. As a
+formula for a suitable soap of this type this may be given.
+
+    Olive Oil Foots              12   parts
+    Corn Oil                     46     "
+    House Grease                 20     "
+    Soda Lye, 36° B.              3     "
+    Potassium Carbonate (dry)     5-3/4 "
+    Potassium Hydrate (solid)    23     "
+
+This soap is made as a "run" soap by the general directions already
+given for a soap thus made. The kettle is boiled with open and closed
+steam, adding water very slowly and aiming to obtain a 220-225 per cent.
+yield or fatty acid content of the finished soap of 46 per cent. When
+the soap is finished a sample cooled on a plate of glass should be
+neither slippery or short, but should string slightly. The finished soap
+is run directly into barrels.
+
+A soap for wool throwing by the semi-boiled process may be made from
+olive oil foots in a crutcher thus:
+
+    Olive Oil Foots          600 lbs.
+    Potash Lye, 20° B.        660 "
+
+The oil is heated to 180° F., the lye added and the mass stirred until
+it bunches, when it is dropped into barrels.
+
+
+WORSTED FINISHING SOAPS.
+
+For the finishing of worsted cloth soaps high in cocoanut oil or palm
+kernel oil are preferred. These soaps are finished very neutral, being
+made as settled soaps, but given an extra wash change after
+strengthening strongly. They are then finished as usual and run into
+barrels. If framed too hot, the high percentage of cocoanut oil causes
+mottling, which is prevented by crutching by hand until the temperature
+of the soap is 140°-145° F. Some typical charges, all of which are
+saponified with soda lye, follow:
+
+                    I.
+
+    Palm Kernel Oil                      60 parts
+    Corn Oil                             40 "
+
+                    II.
+
+    Palm Kernel Oil                      30 "
+    Red Oil (single pressed)             70 "
+
+                    III.
+
+    Red Oil                              33-1/3 "
+    Corn Oil                             33-1/3 "
+    Cocoanut Oil or Palm Kernel Oil      33-1/3 "
+
+
+SOAPS USED IN THE SILK INDUSTRY.
+
+Soap is used to a very large extent in silk mills, both for degumming
+the raw silk and in silk dyeing. Raw silk consists of the true silk
+fibre known as fibroin and a gummy coating, sericin, which dulls the
+lustre of the silk unless removed. For this purpose a slightly alkaline
+olive oil foots soap is best adapted, although palm oil and peanut oil
+soaps are sometimes used, as well as soaps made from a combination of
+house grease to the extent of 30 per cent., together with red oil or
+straight olein soaps, both of which are artificially colored green. In
+using house grease, if 30 per cent. is exceeded in combination with red
+oil, the titer is raised to such an extent that the soap does not
+readily rinse from the silk nor dissolve readily. They are also not
+advisable because they impart a disagreeable odor to the silk.
+
+To make a soap for this purpose from olive oil foots it is made as a
+settled soap, care being taken to thoroughly boil the mass on the
+saponification change in the closed state to assure proper
+saponification. The kettle is usually grained with lye and given a good
+wash change to remove the excess strength. The change previous to the
+finish should not be too heavy or too large a nigre results. The lighter
+the grain is, the better the finished kettle is. A yield of 150 per
+cent. is usually obtained. This soap is generally run to a frame,
+slabbed upon cooling and packed directly into wooden cases.
+
+For silk dyeing the above soap is suitable, although any well-made soap
+of good odor and not rancid is useable. While soap alone is often used
+in the bath for silk dyeing, certain dyestuffs require the addition of
+acetic or sulphuric acid, which sets free the fatty acids. If these be
+of bad odor it is taken up by the silk and is difficult to remove. The
+most generally used soaps are the just mentioned olive foots soap or a
+soap made from a good grade red oil.
+
+Both kinds are extensively used.
+
+
+SOAPS USED FOR COTTON GOODS.
+
+In the manufacture of cotton goods, as compared to the wool and silk
+industries, very much less soap is used and it is only applied to the
+finished fabric either to clean the cloth preparatory to dyeing or to
+aid in dyeing with certain colors. It is also used in calico printing.
+For cleansing the cloth ordinary chip soap is suitable although a more
+alkaline soap finished as a curd soap is an advantage in that the free
+alkali contained therein aids in removing the dirt and has no harmful
+effect on the cotton. For dyeing cotton goods or to brighten certain
+colors after dyeing an olive oil foots soap is most generally employed.
+In calico printing soap is used to wash and clear the cloth after
+printing. A soap for this purpose should be easily soluble in water and
+contain no free alkali, rosin or filler. The best soaps for use in
+calico printing are either an olive oil foots soap or an olein soap.
+
+
+SULPHONATED OILS.
+
+While sulphonated oils are not used to any great extent in the
+manufacture of soap, they are used very largely in the dyeing and
+printing of turkey and alizarine reds on cotton as well as other colors.
+Just what action these oils have is not known. Turkey red oil or
+sulphonated castor oil is the best known sulphonated oil.
+
+The process of making these oils is simple. The equipment necessary is a
+wooden tank or barrel of suitable capacity, approximately two and a half
+times the amount of oil to be treated. There are furthermore required
+other tanks or vessels to hold the solutions used such as caustic soda,
+ammonia and acid. The tank to be used for the preparation of sulphonated
+oil should be provided with a valve at the bottom of the tank and a
+gauge to measure the quantity of liquid therein.
+
+The process is carried out as follows:
+
+Three hundred pounds of castor oil are placed in the tank and 80 pounds
+at 66 deg. B. sulphuric acid are weighed out in another vessel. The acid
+is run into the tank containing the oil in a very thin stream while the
+oil is well stirred. At no time should the temperature exceed 40 deg. C.
+This operation should consume at least an hour and stirring should be
+continued half an hour longer to insure the thorough mixing of the oil
+with the acid. The mass is then allowed to settle for 24 hours, after
+which 40 gallons of water are added and the mixture stirred until it has
+a uniform creamy color indicating no dark streaks. This mixing process
+should be carefully carried out and when completed allowed to settle 36
+hours. At this point the mass will have separated into two layers, the
+lower layer consisting of a water solution of acid and the upper layer
+of oil. The former is run out through the valve located at the bottom of
+the tank. Another wash may now be given or dispensed with as desired. In
+this wash the addition of salt or sodium sulphate at the rate of 1-1/2
+pounds per gallon of water is advisable. A 24 deg. B. caustic soda
+solution is prepared and added slowly to the acidified oil with constant
+stirring. The mass first turns creamy, then becomes streaked, increasing
+in streaks as the caustic solution is poured in, and finally becomes
+clear and transparent. Water is now added to bring the volume to 75
+gallons. The oil is now milky in appearance, but the addition of a
+little more soda solution restores the transparency.
+
+In some cases ammonia is used in addition to caustic soda in
+neutralizing the oil. Three-fourths of the amount of caustic soda
+required to complete the neutralization is first added and then the
+neutralization is completed with a one to one liquid ammonia and water
+solution.
+
+FOOTNOTES:
+
+[9] Seifensieder Ztg., 40, 47, 1266 (1913).
+
+[10] Seifensieder Ztg. (1913), p. 334 and 338.
+         "         "   (1912), p. 1229 and 1257.
+
+[11] Seifensieder Ztg. (1912), p. 954.
+
+
+
+
+CHAPTER V
+
+Glycerine Recovery.
+
+
+The recovery of glycerine is very closely allied with the soap-making
+industry, because glycerine is the very valuable by-product obtained in
+the saponification of oils and fats. No soap plant is, therefore, fully
+equipped unless it has some method whereby the glycerine is recovered
+and the importance of recovering this product cannot be too strongly
+emphasized.
+
+It has already been pointed out that neutral fats or the glycerides are
+a combination of fatty acid with glycerine. These are split apart in the
+process of saponification. While by the term _saponification_ as used in
+soap making it is inferred that this is the combination of caustic
+alkalis with the fatty acids to form soap, this term is by no means
+limited to this method of saponification, as there are various other
+methods of saponifying a fat. The chemical definition of saponification
+is the conversion of an ester, of which glycerides are merely a certain
+type, into an alcohol and an acid or a salt of this acid. Thus, if we
+use caustic alkali as our saponifying agent for a fat or oil, we obtain
+the sodium or potassium salt of the higher fatty acids or soap and the
+alcohol, glycerine. On the other hand, if we use a mineral acid as the
+saponifying agent, we obtain the fatty acids themselves in addition to
+glycerine. While the former is by far the most generally employed for
+making soap, other processes consist in saponifying the fats by some
+method other than caustic alkalis and then converting the fatty acids
+into soap by either neutralizing them with sodium or potassium carbonate
+or hydrate.
+
+It is important to again point out here that fats and oils develop free
+fatty acid of themselves and that the development of this acid
+represents a loss in glycerine. The selection of an oil or fat for soap
+making should therefore to a large extent be judged as to its
+adaptability by the free fatty acid content, as the higher this content
+is, the greater is the loss in the glycerine eventually obtained.
+Glycerine often represents the only profit to a soap manufacturer. It is
+indeed necessary to determine the percentage of free fatty acid before
+purchasing a lot of stock to be made into soap.
+
+In taking up the question of glycerine recovery we will consider the
+various methods thus:
+
+1. Where the glycerine is obtained from spent lye by saponifying the
+fats or oils with caustic alkali.
+
+2. Where the glycerine is obtained by saponifying the fats or oils by
+some other method than the above, of which there are the following:
+
+    (a) Twitchell process.
+    (b) Saponification by lime in autoclave.
+    (c) Saponification by acid.
+    (d) Saponification by water in autoclave.
+    (e) Fermentative (Enzymes).
+    (f) Krebitz process.
+
+
+RECOVERY OF GLYCERINE FROM SPENT LYE.
+
+The spent lye obtained from the glycerine changes in making soap varies
+greatly, the quality depending upon the stock saponified and the soap
+maker's care in handling the operation. No two lyes run exactly alike as
+to proportion of the various ingredients, although they are all similar
+in containing the same substances either in solution or suspension.
+Spent lye is a water solution of mainly glycerine, free alkali either as
+caustic alkali or carbonate and salt, including sodium sulfate, but
+furthermore contains some soap and albuminous matter either in solution
+or suspension. Upon standing in the storage tank the greater part of
+the soap usually separates when the lye cools. In order to assure the
+greatest economical yield of glycerine by saponifying a fat with caustic
+soda it is necessary to obtain a proportion of three parts of water to
+every part of fat made into soap. Test runs have shown that this is the
+proper proportion and that it is not economical to greatly exceed this
+amount, and if a much less proportion is used the full yield of
+glycerine is not obtained.
+
+The spent lyes contain varying amounts of glycerine, the first change
+being richest in glycerine content, and this being reduced in the
+subsequent changes. If the lyes always run high in glycerine it is an
+indication that it is not all being obtained. The usual percentage is
+from 0.5% to 5% or even more, although the average is somewhere around
+2% to 3%. The lye as it comes from the kettle should not contain any
+more than 0.5% to 0.6% of free alkali calculated as sodium carbonate,
+Na_{2}CO_{3}. If the proportion is higher than this, it shows that the
+saponification has been conducted with too high a proportion of alkali,
+a condition which should be corrected in the kettle room. An excess of
+free alkali does not interfere to any great extent with the successful
+recovery of the glycerine, but is a waste of both alkali and the acid
+used in neutralizing this. It is, therefore, more economical to run a
+strong lye over fresh stock and neutralize the alkali thus, rather than
+treating the lye for glycerine recovery.
+
+Before the spent lye can be run into the evaporator it is necessary to
+remove the albuminous impurities and soap and to neutralize the excess
+alkali to between exactly neutral and 0.02% alkalinity. The lye should
+never be fed into the evaporator in the acid condition.
+
+In order to treat the spent lyes for evaporation, they are first allowed
+to cool in the storage tank, after which any soap which may have
+separated is skimmed off and returned to the soap kettle. This lye is
+then pumped to the treatment tank, an ordinary tank equipped with some
+method of agitating the liquor, either by a mechanical stirrer, steam
+blower or compressed air, until it is about two feet from the top.
+
+After the lye has been skimmed off it is thoroughly agitated and a
+sample taken. The amount of lye in the tank is then calculated. Spent
+lye is about 1.09 times heavier than water, or weighs about 9 pounds to
+the gallon. While the sample is being tested for alkalinity it is
+advisable to add sulfate of alumina, which may be dissolving while the
+sample is being titrated. This substance should be added in the
+proportion of anywhere from 6 to 14 pounds per thousand pounds of lye,
+depending upon the amount of impurities contained therein. For a clean
+lye six pounds per thousand is sufficient, but for an impure lye a
+greater quantity is necessary. The sulfate of alumina used should be
+free from arsenic and sulfides and should contain a minimum amount of
+grit (silica), as grit reduces the life of the pump valves. This may be
+estimated with sufficient accuracy by rubbing the filtered-off portions,
+insoluble in water between the fingers and a plate of glass. The object
+of adding the sulfate of alumina is to transform the soap contained in
+the lye into the insoluble aluminum soaps, and at the same time to
+coagulate the albuminous impurities. It must be remembered that the
+sulfate of alumina is added only for the fresh lye put into the tank.
+Thus if there were 10,000 pounds of lye in the treating tank when the
+fresh lye was run in, and 50,000 pounds when the tank is filled, adding
+nine pounds of sulfate of alumina per thousand of lye, only 360 pounds
+would be added or enough for 40,000 pounds. Sulfate of alumina
+neutralizes one-third of its weight of caustic.
+
+To determine the alkali in the sample, 10 cubic centimeters are pipetted
+into a beaker, a little distilled water added, then 3 or 4 drops of
+phenolphthalein indicator. From a burette, quarter normal (N/4) sulfuric
+acid is added until the pink color is just discharged. When this point
+is reached 4 to 5 c. c. more of acid are added and the solution is
+boiled to expel the carbon dioxide. Should the solution turn pink, it is
+necessary to add more acid. After having boiled for 3 to 4 minutes, N/4
+caustic soda is added until the pink color just returns and the amount
+of caustic soda used is read on the burette. The difference between the
+number of cubic centimeters of N/4 sulfuric acid and N/4 caustic soda
+gives the amount of alkali in the sample. By using a 10 c. c. sample and
+N/4 sulfuric acid and N/4 caustic soda each c. c. obtained by the
+difference of these two solutions is equal to one-tenth of one per cent.
+(0.1%) of the total alkali in the lye. As an example, say we first used
+7.7 c. c. of N/4 sulfuric acid to just discharge the pink, then added 4
+c. c. more, or 11.7 c. c. in total. After boiling it required 5.3 c. c.
+to bring back a slight pink, the total alkalinity would be 11.7 c. c. -
+5.3 c. c. = 6.4 c. c., or 0.64% total alkali in the lye in terms of
+caustic soda. If there were 40,000 pounds of lye to be treated then we
+should have to neutralize:
+
+40,000 × .0064 = 256 lbs. alkali. Since sulfate of alumina neutralizes
+one-third of its weight in caustic, and there are say 9 lbs. of this
+added per thousand pounds of lye we would add
+
+40,000 × 9 = 360 lbs. of sulfate of alumina. This would neutralize 360 ×
+1/3 = 120 lbs of alkali. There are then 256 - 120 = 136 lbs. of alkali
+still to be neutralized. If 60° B. sulfuric acid is used it requires
+about 1.54 lbs. of acid to one pound of caustic. Therefore to neutralize
+the caustic soda remaining it requires:
+
+136 × 1.54 = 209.44 lbs. 60° B. sulfuric acid to neutralize the total
+alkali in the 40,000 pounds of spent lye.
+
+The acid is added and the lye well stirred, after which another sample
+is taken and again titrated as before. From this titration the amount of
+acid to be added is again calculated and more acid is added if
+necessary. Should too much acid have been added, caustic soda solution
+is added until the lye is between exactly neutral and 0.02% alkaline.
+The filtered lyes at this stage have a slight yellowish cast.
+
+To be sure that the lyes are treated correctly the precipitation test is
+advisable. To carry this out filter about 50 c. c. of the treated lye
+and divide into two portions in a test tube. To one portion add ammonia
+drop by drop. If a cloudiness develops upon shaking, more alkali is
+added to the lye in the tank. To the other portion add a few drops of 1
+to 5 sulfuric acid and shake the test tube. If a precipitate develops or
+the solution clouds, more acid is needed. When the lyes are treated
+right no cloudiness should develop either upon adding ammonia or the
+dilute acid.
+
+The properly treated lye is then run through the filter press while
+slightly warm and the filtered lye is fed to the evaporator from the
+filtered lye tank. The lye coming from the filter press should be clear
+and have a slight yellowish cast. As the pressure increases it is
+necessary to clean the press or some of the press cake will pass through
+the cloths. Where sodium silicate is used as a filler, the silicate
+scrap should never be returned to the soap kettle until the glycerine
+lyes have been withdrawn. This practice of some soapmakers is to be
+strongly censured, as it causes decided difficulty in filtering the lye,
+since during the treatment of the lye, free silicic acid in colloidal
+form is produced by the decomposition of the sodium silicate by acid.
+This often prevents filtering the treated lye even at excess pressure
+and at its best retards the filtering.
+
+As to the filter press cake, this may be best thrown away in a small
+factory. Where, however, the output of glycerine is very large it pays
+to recover both the fatty acids and alumina in the press cakes.
+
+In some cases, especially when the lyes are very dirty and the total
+residue in the crude glycerine runs high, for which there is a penalty
+usually attached, a double filtration of the lye is advisable. This is
+carried out by first making the lye slightly acid in reaction by the
+addition of alum and acid, then filtering. This filtered lye is then
+neutralized to the proper point with caustic, as already described, and
+passed through the filter press again.
+
+While in the method of treating the lyes as given sulfuric acid is used
+for neutralizing, some operators prefer to use hydrochloric acid, as
+this forms sodium chloride or common salt, whereas sulfuric acid forms
+sodium sulfate, having 3/5 the graining power of salt, which eventually
+renders the salt useless for graining the soap, as the percentage of
+sodium sulfate increases in the salt. When the salt contains 25 per
+cent. sodium sulfate it is advisable to throw it away. Sulfuric acid,
+however, is considerably cheaper than hydrochloric and this more than
+compensates the necessity of having to eventually reject the recovered
+salt. It may here also be mentioned that recovered salt contains 5-7 per
+cent. glycerine which should be washed out in the evaporator before it
+is thrown away. The following tables give the approximate theoretical
+amounts of acids of various strengths required to neutralize one pound
+of caustic soda:
+
+For 1 pound of caustic soda--
+
+    3.25 lbs. 18° B. hydrochloric (muriatic) acid are required.
+    2.92  "   20° B.      "            "       "   "     "
+    2.58  "   22° B.      "            "       "   "     "
+
+For 1 pound of caustic soda--
+
+    1.93 lbs. 50° B. sulphuric acid are required.
+    1.54  "   60° B.     "      "    "     "
+    1.28  "   66° B.     "      "    "     "
+
+It is, of course, feasible to neutralize the spent lye without first
+determining the causticity by titrating a sample and this is often the
+case. The operator under such conditions first adds the sulfate of
+alumina, then the acid, using litmus paper as his indicator.
+Comparatively, this method of treatment is much slower and not as
+positive, as the amount of acid or alkali to be added is at all times
+uncertain, for in the foaming of the lyes their action on litmus is
+misleading.
+
+After the lye has been filtered to the filtered lye tank it is fed to
+the evaporator, the method of operation of which varies somewhat with
+different styles or makes. When it first enters the evaporator the lye
+is about 11°-12° B. After boiling the density will gradually rise to 27°
+B. and remain at this gravity for some time and during which time most
+of the salt is dropped out in the salt filter. As the lye concentrates
+the gravity gradually rises to 28°-30° B., which is half crude glycerine
+and contains about 60 per cent. glycerine. Some operators carry the
+evaporation to this point and accumulate a quantity of half crude before
+going on to crude. After half crude is obtained the temperature on the
+evaporator increases, the vacuum increases and the pressure on the
+condensation drain goes up (using the same amount of live steam). As the
+liquor grows heavier the amount of evaporation is less, and less steam
+is required necessitating the regulation of the steam pressure on the
+drum. When a temperature of 210° F. on the evaporator, with 26 or more
+inches vacuum on the pump is arrived at, the crude stage has been
+reached and the liquor now contains about 80 per cent. glycerine in
+which shape it is usually sold by soap manufacturers. A greater
+concentration requires more intricate apparatus. After settling a day in
+the crude tank it is drummed.
+
+Crude glycerine (about 80 per cent. glycerol) free from salt is 33° B.,
+or has a specific gravity of 1.3. A sample boiled in an open dish boils
+at a temperature of 155° C. or over.
+
+
+TWITCHELL PROCESS.
+
+The Twitchell process of saponification consists of causing an almost
+complete cleavage of fats and oils by the use of the Twitchell reagent
+or saponifier, a sulfo-aromatic compound. This is made by the action of
+concentrated sulfuric acid upon a solution of oleic acid or stearic acid
+in an aromatic hydrocarbon. From 0.5 per cent. to 3 per cent. of the
+reagent is added and saponification takes place from 12-48 hours by
+heating in a current of live steam. The reaction is usually accelerated
+by the presence of a few per cent. of free fatty acids as a starter.
+Recently the Twitchell double reagent has been introduced through which
+it is claimed that better colored fatty acids are obtained and the
+glycerine is free from ash.
+
+The advantages claimed for the Twitchell process as outlined by
+Joslin[12] are as follows:
+
+1. All the glycerine is separated from the stock before entering the
+kettle, preventing loss of glycerine in the soap and removing glycerine
+from spent lye.
+
+2. The liquors contain 15-20 per cent. glycerine whereas spent lyes
+contain but 3-5 per cent. necessitating less evaporation and
+consequently being more economical in steam, labor and time.
+
+3. No salt is obtained in the liquors which makes the evaporation
+cheaper and removes the cause of corrosion of the evaporator; also
+saves the glycerine retained by the salt.
+
+4. The glycerine liquors are purer and thus the treatment of the lyes is
+cheaper and simpler and the evaporation less difficult.
+
+5. The glycerine can readily be evaporated to 90 per cent. crude rather
+than 80 per cent. crude, thus saving drums, labor in handling and
+freight. The glycerine furthermore receives a higher rating and price,
+being known as saponification crude which develops no glycols in
+refining it.
+
+6. The fatty acids obtained by the Twitchell saponifier may be converted
+into soap by carbonates, thus saving cost in alkali.
+
+7. There is a decrease in the odor of many strong smelling stocks.
+
+8. The glycerine may be obtained from half boiled and cold made soaps as
+well as soft (potash) soaps.
+
+While the advantages thus outlined are of decided value in the
+employment of the Twitchell process, the one great disadvantage is that
+the fatty acids obtained are rather dark in color and are not
+satisfactorily employed for the making of a soap where whiteness of
+color is desired.
+
+To carry out the process the previously heated oil or fat to be
+saponified is run into a lead lined tank. As greases and tallow often
+contain impurities a preliminary treatment with sulfuric acid is
+necessary. For a grease 1.25 per cent. of half water and half 66° B.
+sulfuric acid is the approximate amount. The undiluted 66° B. acid
+should never be added directly, as the grease would be charred by this.
+The grease should be agitated by steam after the required percentage of
+acid, calculated on the weight of the grease, has been added. The wash
+lye coming off should be 7°-10° B. on a good clean grease or 15°-22° B.
+on cotton oil or a poor grease. As has been stated the grease is heated
+before the acid is added or the condensation of the steam necessitates
+the addition of more acid. After having boiled for 1-2 hours the grease
+is allowed to settle for 12 hours and run off through a swivel pipe.
+
+After the grease has been washed, as just explained, and settled, it is
+pumped into a covered wooden tank containing an open brass coil. Some of
+the second lye from a previous run is usually left in this tank and the
+grease pumped into this. The amount of this lye should be about
+one-third to one-half the weight of the grease so that there is about 60
+per cent. by weight of grease in the tank after 24 hours boiling. Where
+occasions arise when there is no second lye about 50 per cent. by weight
+of distilled water to the amount of grease is run into the tank to
+replace the lye. The saponifier is then added through a glass or granite
+ware funnel after the contents of the tank have been brought to a boil.
+If the boiling is to be continued 48 hours, 1 per cent. of saponifier is
+added. For 24 hours boiling add 1.5 per cent. The boiling is continued
+for 24-48 hours allowing 18 inches for boiling room or the grease will
+boil over.
+
+After boiling has continued the required length of time the mass is
+settled and the glycerine water is drawn off to the treatment tank.
+Should a permanent emulsion have formed, due to adding too great an
+amount of saponifier, a little sulfuric acid (0.1 per cent.-0.3 per
+cent.) will readily break this. During the time this is being done the
+space between the grease and the cover on the tank is kept filled with
+steam as contact with the air darkens the fatty acids.
+
+To the grease remaining in the tank distilled water (condensed water
+from steam coils) to one-half its volume is added and the boiling
+continued 12-24 hours. The grease is then settled and the clear grease
+run off through a swivel pipe. A layer of emulsion usually forms between
+the clear grease and lye so that it may easily be determined when the
+grease has all been run off. To prevent discoloration of the fatty acids
+it is necessary to neutralize the lye with barium carbonate. The amount
+of this to be added depends upon the percentage of saponifier used.
+About 1/10 the weight of saponifier is the right amount. The barium
+carbonate is added through the funnel at the top of the tank mixed with
+a little water and the lye tested until it is neutral to methyl orange
+indicator. When the fatty acids are thus treated they will not darken
+upon exposure to the air when run off.
+
+Fresh grease is now pumped into the lye or water remaining in the tank
+and the process repeated.
+
+The glycerine water or first lye is run to the treatment tank, the fat
+skimmed off and neutralized with lime until it shows pink with
+phenolphthalein, after having been thoroughly boiled with steam. About
+0.25 per cent. lime is the proper amount to add. The mixture is then
+allowed to settle and the supernatant mixture drawn off and run to the
+glycerine evaporator feed tank. The lime which holds considerable
+glycerine is filtered and the liquor added to the other. The evaporation
+is carried out in two stages. The glycerine water is first evaporated to
+about 60 per cent. glycerol, then dropped into a settling tank to settle
+out the calcium sulfate. The clear liquor is then evaporated to crude
+(about 90 per cent. glycerine) and the sediment filtered and also
+evaporated to crude.
+
+As to the amount of saponifier to use on various stocks, this is best
+determined by experiment as to how high a percentage gives dark colored
+fatty acids. For good stock such as clean tallow, prime cottonseed oil,
+corn oil, cocoanut oil and stock of this kind 0.75 per cent. saponifier
+is sufficient. For poorer grades of tallow, house grease, poor
+cottonseed oil, etc., 1 per cent. saponifier is required and for poorer
+grade greases higher percentages. The percentage of fatty acids
+developed varies in various stocks, and also varies with the care that
+the operation is carried out, but is usually between 85 per cent.-95 per
+cent. Due to the water taken up in the saponification process there is a
+yield of about 103 pounds of fatty acids and glycerine for 100 pounds of
+fat.
+
+The Twitchell reagent has undoubtedly caused a decided advance in the
+saponification of fats and oils and has been of great value to the soap
+manufacturer, because with a small expenditure it is possible to compete
+with the much more expensive equipment necessary for autoclave
+saponification. The drawback, however, has been that the reagent
+imparted a dark color to the fatty acids obtained, due to decomposition
+products forming when the reagent is made, and hence is not suitable for
+use in soaps where whiteness of color is desired.
+
+There have recently been two new reagents introduced which act as
+catalyzers in splitting fats, just as the Twitchell reagent acts, but
+the fatty acids produced by the cleavage are of good color. The
+saponification, furthermore, takes place more rapidly. These are the
+Pfeilring reagent and Kontact reagent.
+
+The Pfeilring reagent is very similar to the Twitchell reagent, being
+made from hydrogenated castor oil and naphthalene by sulfonation with
+concentrated sulfuric acid. It is manufactured in Germany and is being
+extensively used in that country with good success.
+
+The Kontact or Petroff reagent, discovered by Petroff in Russia, is made
+from sulfonated mineral oils. Until very recently it has only been
+manufactured in Europe, but now that it has been found possible to
+obtain the proper mineral constituent from American petroleum, it is
+being manufactured in this country, and it is very probable that it will
+replace the Twitchell reagent because of the advantages derived by using
+it, as compared to the old Twitchell reagent.
+
+The method and equipment necessary for employing either the Pfeilring or
+Kontact reagents is exactly the same as in using the Twitchell process.
+
+
+AUTOCLAVE SAPONIFICATION.
+
+While the introduction of the Twitchell process to a great extent
+replaced the autoclave method of saponification for obtaining fatty
+acids for soap making, the autoclave method is also used. This process
+consists in heating the previously purified fat or oil in the presence
+of lime and water, or water only, for several hours, which causes a
+splitting of the glycerides into fatty acids and glycerine. The
+advantage of autoclave saponification over the Twitchell process is that
+a greater cleavage of the fats and oils results in less time and at a
+slightly less expense. The glycerine thus obtained is also purer and of
+better color than that obtained by Twitchelling the fats.
+
+An autoclave or digestor consists of a strongly constructed, closed
+cylindrical tank, usually made of copper, and is so built as to resist
+internal pressure. The digestor is usually 3 to 5 feet in diameter and
+from 18 to 25 feet high. It may be set up horizontally or vertically and
+is covered with an asbestos jacket to retain the heat. Various inlets
+and outlets for the fats, steam, etc., as well as a pressure gauge and
+safety valve are also a necessary part of the equipment.
+
+
+LIME SAPONIFICATION.
+
+The saponification in an autoclave is usually carried out by introducing
+the fats into the autoclave with a percentage of lime, magnesia or zinc
+oxide, together with water. If the fats contain any great amount of
+impurities, it is first necessary to purify them either by a treatment
+with weak sulfuric acid, as described under the Twitchell process, or by
+boiling them up with brine and settling out the impurities from the hot
+fat.
+
+To charge the autoclave a partial vacuum is created therein by
+condensation of steam just before running the purified oil in from an
+elevated tank. The required quantity of unslaked lime, 2 to 4 per cent.
+of the weight of the fat, is run in with the molten fat, together with
+30 per cent. to 50 per cent. of water. While 8.7 per cent. lime is
+theoretically required, practice has shown that 2 per cent. to 4 per
+cent. is sufficient. The digestor, having been charged and adjusted,
+steam is turned on and a pressure of 8 to 10 atmospheres maintained
+thereon for a period of six to ten hours. Samples of the fat are taken
+at various intervals and the percentage of free fatty acids determined.
+When the saponification is completed the contents of the autoclave are
+removed, usually by blowing out the digestor into a wooden settling
+tank, or by first running off the glycerine water and then blowing out
+the lime, soap and fatty acids. The mass discharged from the digestor
+separates into two layers, the upper consisting of a mixture of lime
+soap or "rock" and fatty acids, and the lower layer contains the
+glycerine or "sweet" water. The glycerine water is first run off through
+a clearing tank or oil separator, if this has not been done directly
+from the autoclave, and the mass remaining washed once or twice more
+with water to remove any glycerine still retained by the lime soap. The
+calculated amount of sulfuric acid to decompose the lime "rock" is then
+added, and the mass agitated until the fatty acids contained therein are
+entirely set free. Another small wash is then given and the wash water
+added to the glycerine water already run off. The glycerine water is
+neutralized with lime, filtered and concentrated as in the Twitchell
+process.
+
+Due to the difficulties of working the autoclave saponification with
+lime, decomposing the large amount of lime soap obtained and dealing
+with much gypsum formed thereby which collects as a sediment and
+necessitates cleaning the tanks, other substances are used to replace
+lime. Magnesia, about 2 per cent. of the weight of the fat, is used and
+gives better results than lime. One-half to 1 per cent. of zinc oxide of
+the weight of the fat is even better adapted and is now being
+extensively employed for this purpose. In using zinc oxide it is
+possible to recover the zinc salts and use them over again in the
+digestor, which makes the process as cheap to work as with lime, with
+far more satisfactory results.
+
+
+ACID SAPONIFICATION.
+
+While it is possible to saponify fats and oils in an autoclave with the
+addition of acid to the fat, unless a specially-constructed digestor is
+built, the action of the acid on the metal from which the autoclave is
+constructed prohibits its use. The acid saponification is therefore
+carried out by another method.
+
+The method of procedure for acid saponification, therefore, is to first
+purify the fats with dilute acid as already described. The purified, hot
+or warm, dry fat is then run to a specially-built acidifier or a
+lead-lined tank and from 4 per cent. to 6 per cent. of concentrated
+sulfuric acid added to the fat, depending upon its character, the degree
+of saponification required, temperature and time of saponification. A
+temperature of 110 degrees C. is maintained and the mass mixed from four
+to six hours. The tank is then allowed to settle out the tar formed
+during the saponification, and the fatty acids run off to another tank
+and boiled up about three times with one-third the amount of water. The
+water thus obtained contains the glycerine, and after neutralization is
+concentrated.
+
+
+AQUEOUS SAPONIFICATION.
+
+While lime or a similar substance is ordinarily used to aid in splitting
+fats in an autoclave, the old water process is still used. This is a
+convenient, though slower and more dangerous method, of producing the
+hydrolysis of the glyceride, as well as the simplest in that fatty acids
+and glycerine in a water solution are obtained. The method consists in
+merely charging the autoclave with fats and adding about 30 per cent. to
+40 per cent. of their weight of water, depending on the amount of free
+fatty acid and subjecting the charge to a pressure of 150 to 300 pounds,
+until the splitting has taken place. This is a much higher pressure than
+when lime is used and therefore a very strong autoclave is required.
+Since fatty acids and pure glycerine water are obtained no subsequent
+treatment of the finished charge is necessary except separating the
+glycerine water and giving the fatty acids a wash with water to remove
+all the glycerine from them.
+
+
+SPLITTING FATS WITH FERMENTS.
+
+In discussing the causes of rancidity of oils and fats it was pointed
+out that the initial splitting of these is due to enzymes, organized
+ferments. In the seeds of the castor oil plant, especially in the
+protoplasm of the seed, the enzyme which has the property of causing
+hydrolysis of the glycerides is found. The ferment from the seeds of the
+castor oil plant is now extracted and used upon a commercial basis for
+splitting fats.
+
+The equipment necessary to carry out this method of saponification is a
+round, iron, lead-lined tank with a conical bottom, preferably about
+twice as long as it is wide. Open and closed steam coils are also
+necessary in the tank.
+
+The oils are first heated and run into this tank. The right temperature
+to heat these to is about 1 degree to 2 degrees above their
+solidification point. For liquid oils 23 degrees C. is the proper heat
+as under 20 degrees C. the cleavage takes place slowly. Fats titering 44
+degrees C. or above must be brought down in titer by mixing with them
+oils of a lower titer as the ferment or enzyme is killed at about 45
+degrees C. and thus loses its power of splitting. It is also necessary
+to have the fat in the liquid state or the ferment does not act. The
+proper temperature must be maintained with dry steam.
+
+It is, of course, necessary to add water, which may be any kind desired,
+condensed, water from steam coils, well, city, etc. From 30 per cent. to
+40 per cent., on the average 35 per cent. of water is added, as the
+amount necessary is regulated so as to not dilute the glycerine water
+unnecessarily. To increase the hydrolysis a catalyzer, some neutral
+salt, usually manganese sulfate is added in the proportion of 0.15 per
+cent. appears to vary directly as the saponification number of the fat
+or oil. The approximate percentages of fermentive substance to be added
+to various oils and fats follow:
+
+    Cocoanut oil          8   %
+    Palm Kernel oil       8   %
+    Cottonseed oil        6-7 %
+    Linseed oil           4-5 %
+    Tallow oil            8-10%
+
+The oil, water, manganese sulfate and ferment having been placed in the
+tank in the order named, the mixture is agitated with air for about a
+quarter of an hour to form an even emulsion, in which state the mass is
+kept by stirring occasionally with air while the saponification is
+taking place. A temperature is maintained a degree or two above the
+titer point of the fat with closed steam which may be aided by covering
+the tank for a period of 24 to 48 hours. The splitting takes place
+rapidly at first, then proceeds more slowly. In 24 hours 80 per cent. of
+the fats are split and in 48 hours 85 per cent. to 90 per cent.
+
+When the cleavage has reached the desired point the mass is heated to 80
+degrees-85 degrees C. with live or indirect steam while stirring with
+air. Then 0.1 per cent.-0.15 per cent of concentrated sulfuric acid
+diluted with water is added to break the emulsion. When the emulsion is
+broken the glycerine water is allowed to settle out and drawn off. The
+glycerine water contains 12 per cent. to 25 per cent. glycerine and
+contains manganese sulfate, sulfuric acid and albuminous matter. Through
+neutralization with lime at boiling temperature and filtration the
+impurities can almost all be removed after which the glycerine water may
+be fed to the evaporator. Should it be desired to overcome the trouble
+due to the gypsum formed in the glycerine, the lime treatment may be
+combined with a previous treatment of the glycerine water with barium
+hydrate to remove the sulfuric acid, then later oxalic acid to
+precipitate the lime.
+
+The fatty acids obtained by splitting with ferments are of very good
+color and adaptable for soap making.
+
+
+KREBITZ PROCESS.
+
+The Krebitz process which has been used to some extent in Europe is
+based upon the conversion of the fat or oil into lime soap which is
+transformed into the soda soap by the addition of sodium carbonate. To
+carry out the process a convenient batch of, say, 10,000 pounds of fat
+or oil, is run into a shallow kettle containing 1,200 to 1,400 pounds of
+lime previously slaked with 3,700 to 4,500 pounds of water. The mass is
+slowly heated with live steam to almost boiling until an emulsion is
+obtained. The tank is then covered and allowed to stand about 12 hours.
+The lime soap thus formed is dropped from the tank into the hopper of a
+mill, finely ground and conveyed to a leeching tank. The glycerine is
+washed out and the glycerine water run to a tank for evaporation. The
+soap is then further washed and these washings are run to other tanks to
+be used over again to wash a fresh batch of soap. About 150,000 pounds
+of water will wash the soap made from 10,000 pounds of fat which makes
+between 15,000 and 16,000 pounds of soap. The first wash contains
+approximately 10 per cent. glycerine and under ordinary circumstances
+this only need be evaporated for glycerine recovery.
+
+After extracting the glycerine the soap is slowly introduced into a
+boiling solution of sodium carbonate or soda ash and boiled until the
+soda has replaced the lime. This is indicated by the disappearance of
+the small lumps of lime soap. Caustic soda is then added to saponify the
+fat not converted by the lime saponification. The soap is then salted
+out and allowed to settle out the calcium carbonate. This drops to the
+bottom of the kettle as a heavy sludge entangling about 10 per cent. of
+the soap. A portion of this soap may be recovered by agitating the
+sludge with heat and water, pumping the soap off the top and filtering
+the remaining sludge.
+
+While the soap thus obtained is very good, the percentage of glycerine
+recovered is greatly increased and the cost of alkali as carbonate is
+less. The disadvantages are many. Large quantities of lime are required;
+it is difficult to recover the soap from the lime sludge; the operations
+are numerous prior to the soap making proper and rather complicated
+apparatus is required.
+
+
+DISTILLATION OF FATTY ACIDS.
+
+The fatty acids obtained by various methods of saponification may be
+further improved by distillation.
+
+In order to carry out this distillation, two methods may be pursued,
+first, the continuous method, whereby the fatty acids are continually
+distilled for five to six days, and, second, the two phase method,
+whereby the distillation continues for 16 to 20 hours, after which the
+residue is drawn off, treated with acid, and its distillate added to a
+fresh charge of fatty acids. The latter method is by far the best, since
+the advantages derived by thus proceeding more than compensate the
+necessity of cleaning the still. Better colored fatty acids are
+obtained; less unsaponifiable matter is contained therein; there is no
+accumulation of impurities; the amount of neutral fat is lessened
+because the treatment of the tar with acid causes a cleavage of the
+neutral fat and the candle tar or pitch obtained is harder and better
+and thus more valuable.
+
+The stills are usually built of copper, which are heated by both direct
+fire and superheated steam. Distillation under vacuum is advisable. To
+begin the distilling operation, the still is first filled with dry hot
+fatty acids to the proper level. Superheated steam is then admitted and
+the condenser is first heated to prevent the freezing of the fatty
+acids, passing over into same. When the temperature reaches 230 deg. C.
+the distillation begins. At the beginning, the fatty acids flow from the
+condenser, an intense green color, due to the formation of copper soaps
+produced by the action of the fatty acids on the copper still. This
+color may easily be removed by treating with dilute acid to decompose
+the copper soaps.
+
+In vacuum distillation, the operation is begun without the use of
+vacuum. Vacuum is introduced only when the distillation has proceeded
+for a time and the introduction of this must be carefully regulated,
+else the rapid influence of vacuum will cause the contents of the still
+to overflow. When distillation has begun a constant level of fatty acids
+is retained therein by opening the feeding valve to same, and the heat
+is so regulated as to produce the desired rate of distillation. As soon
+as the distillate flows darker and slower, the feeding valve to the
+still is shut off and the distillation continued until most of the
+contents of the still are distilled off, which is indicated by a rise in
+the temperature. Distillation is then discontinued, the still shut down,
+and in about an hour the contents are sufficiently cool to be emptied.
+The residue is run off into a proper receiving vessel, treated with
+dilute acid and used in the distillation of tar.
+
+In the distillation of tar the same method as the above is followed,
+only distillation proceeds at a higher temperature. The first portion
+and last portion of the distillate from tar are so dark that it is
+necessary to add them to a fresh charge of fatty acids. By a well
+conducted distillation of tar about 50 per cent. of the fatty acids from
+the tar can be used to mix with the distilled fatty acids. The residue
+of this operation called stearine pitch or candle tar consists of a
+hard, brittle, dark substance. Elastic pitch only results where
+distillation has been kept constant for several days without
+interrupting the process, and re-distilling the tar. In a good
+distillation the distillation loss is 0.5 to 1.5% and loss in pitch
+1.5%. Fatty acids which are not acidified deliver about 3% of pitch.
+Very impure fats yield even a higher percentage in spite of acidifying.
+For a long time it was found impossible to find any use for stearine
+pitch, but in recent years a use has been found for same in the
+electrical installation of cables.
+
+FOOTNOTES:
+
+[12] Journ. Ind. Eng. Chem. (1909), I, p. 654.
+
+
+
+
+CHAPTER VI
+
+Analytical Methods.
+
+
+While it is possible to attain a certain amount of efficiency in
+determining the worth of the raw material entering into the manufacture
+of soap through organoleptic methods, these are by no means accurate. It
+is, therefore, necessary to revert to chemical methods to correctly
+determine the selection of fats, oil or other substances used in soap
+making, as well as standardizing a particular soap manufactured and to
+properly regulate the glycerine recovered.
+
+It is not our purpose to cover in detail the numerous analytical
+processes which may be employed in the examination of fats and oils,
+alkalis, soap and glycerine, as these are fully and accurately covered
+in various texts, but rather to give briefly the necessary tests which
+ought to be carried out in factories where large amounts of soap are
+made. Occasion often arises where it is impossible to employ a chemist,
+yet it is possible to have this work done by a competent person or to
+have someone instruct himself as just how to carry out the more simple
+analyses, which is not a very difficult matter. The various standard
+solutions necessary to carrying out the simpler titrations can readily
+be purchased from dealers in chemical apparatus and it does not take
+extraordinary intelligence for anyone to operate a burette, yet in many
+soap plants in this country absolutely no attention is paid to the
+examining of raw material, though many thousand pounds are handled
+annually, which, if they were more carefully examined would result in
+the saving of much more money than it costs to examine them or have
+them at least occasionally analyzed.
+
+
+ANALYSIS OF FATS AND OILS.
+
+In order to arrive at proper results in the analysis of a fat or oil, it
+is necessary to have a proper sample. To obtain this a sample of several
+of the packages of oil or fat is taken and these mixed or molten
+together into a composite sample which is used in making the tests. If
+the oil or fat is solid, a tester is used in taking the sample from the
+package and if they are liquid, it is a simple matter to draw off a
+uniform sample from each package and from these to form a composite
+sample.
+
+In purchasing an oil or fat for soap making, the manufacturer is usually
+interested in the amount of free fatty acid contained therein, of
+moisture, the titer, the percentage of unsaponifiable matter and to
+previously determine the color of soap which will be obtained where
+color is an object.
+
+
+DETERMINATION OF FREE FATTY ACIDS.
+
+Since the free fatty acid content of a fat or oil represents a loss of
+glycerine, the greater the percentage of free fatty acid, the less
+glycerine is contained in the fat or oil, it is advisable to purchase a
+fat or oil with the lower free acid, other properties and the price
+being the same.
+
+While the mean molecular weight of the mixed free fatty acids varies
+with the same and different oils or fats and should be determined for
+any particular analysis for accuracy, the free fatty acid is usually
+expressed as oleic acid, which has a molecular weight of 282.
+
+To carry out the analysis 5 to 20 grams of the fat are weighed out into
+an Erlenmeyer flask and 50 cubic centimeters of carefully neutralized
+alcohol are added. In order to neutralize the alcohol add a few drops of
+phenolphthalein solution to same and add a weak caustic soda solution
+drop by drop until a very faint pink color is obtained upon shaking or
+stirring the alcohol thoroughly. The mixture of fat and neutralized
+alcohol is then heated to boiling and titrated with tenth normal alkali
+solution, using phenolphthalein as an indicator. As only the free fatty
+acids are readily soluble in the alcohol and the fat itself only
+slightly mixes with it, the flask should be well agitated toward the end
+of the titration. When a faint pink color remains after thoroughly
+agitating the flask the end point is reached. In order to calculate the
+percentage of free fatty acid as oleic acid, multiply the number of
+cubic centimeters of tenth normal alkali used as read on the burette by
+0.0282 and divide by the number of grams of fat taken for the
+determination and multiply by 100.
+
+When dark colored oils or fats are being titrated it is often difficult
+to obtain a good end point with phenolphthalein. In such cases about 2
+cubic centimeters of a 2 per cent. alcoholic solution of Alkali Blue 6 B
+is recommended.
+
+Another method of directly determining the free fatty acid content of
+tallow or grease upon which this determination is most often made is to
+weigh out into an Erlenmeyer flask exactly 5.645 grams of a sample of
+tallow or grease. Add about 75 cubic centimeters of neutralized alcohol.
+Heat until it boils, then titrate with tenth normal alkali and divide
+the reading by 2, which gives the percentage of free fatty acid as
+oleic. If a fifth normal caustic solution is used, the reading on the
+burette gives the percentage of free fatty acid directly. This method,
+while it eliminates the necessity of calculation, is troublesome in that
+it is difficult to obtain the exact weight of fat.
+
+
+MOISTURE.
+
+To calculate the amount of moisture contained in a fat or oil 5 to 10
+grams are weighed into a flat bottom dish, together with a known amount
+of clean, dry sand, if it is so desired. The dish is then heated over a
+water bath, or at a temperature of 100-110 degs. C., until it no longer
+loses weight upon drying and reweighing the dish. One hour should elapse
+between the time the dish is put on the water bath and the time it is
+taken off to reweigh. The difference between the weight of the dish is
+put on the water bath and the time it is taken off when it reaches a
+constant weight is moisture. This difference divided by the original
+weight of the fat or oil × 100 gives the percentage of moisture.
+
+When highly unsaturated fats or oils are being analyzed for moisture, an
+error may be introduced either by the absorption of oxygen, which is
+accelerated at higher temperature, or by the formation of volatile fatty
+acids. The former causes an increase in weight, the latter causes a
+decrease. To obviate this, the above operation of drying should be
+carried out in the presence of some inert gas like hydrogen, carbon
+dioxide, or nitrogen.
+
+
+TITER.
+
+The titer of a fat or oil is really an indication of the amount of
+stearic acid contained therein. The titer, expressed in degrees
+Centigrade, is the solidification point of the fatty acids of an oil or
+fat. In order to carry out the operation a Centigrade thermometer
+graduated in one or two-tenths of a degree is necessary. A thermometer
+graduated between 10 degs. centigrade to 60 degs. centigrade is best
+adapted and the graduations should be clear cut and distinct.
+
+To make the determination about 30 grams of fat are roughly weighed in a
+metal dish and 30-40 cubic centimeters of a 30 per cent. (36 degs.
+Baumé) solution of sodium hydroxide, together with 30-40 cubic
+centimeters of alcohol, denatured alcohol will do, are added and the
+mass heated until saponified. Heat over a low flame or over an asbestos
+plate until the soap thus formed is dry, constantly stirring the
+contents of the dish to prevent burning. The dried soap is then
+dissolved in about 1000 cubic centimeters of water, being certain that
+all the alcohol has been expelled by boiling the soap solution for about
+half an hour. When the soap is in solution add sufficient sulphuric acid
+to decompose the soap, approximately 100 cubic centimeters of 25 degs.
+Baumé sulphuric acid, and boil until the fatty acids form a clear layer
+on top of the liquid. A few pieces of pumice stone put into the mixture
+will prevent the bumping caused by boiling. Siphon off the water from
+the bottom of the dish and wash the fatty acids with boiling water until
+free from sulphuric acid. Collect the fatty acids in a small casserole
+or beaker and dry them over a steam bath or drying oven at 110 degs.
+Centigrade. When the fatty acids are dry, cool them to about 10 degs.
+above the titer expected and transfer them to a titer tube or short test
+tube which is firmly supported by a cork in the opening of a salt mouth
+bottle. Hang the thermometer by a cord from above the supported tube so
+it reaches close to the bottom when in the titer tube containing the
+fatty acids and so that it may be used as a stirrer. Stir the mass
+rather slowly, closely noting the temperature. The temperature will
+gradually fall during the stirring operation and finally remain
+stationary for half a minute or so then rise from 0.1 to 0.5 degs. The
+highest point to which the mercury rises after having been stationary is
+taken as the reading of the titer.
+
+
+DETERMINATION OF UNSAPONIFIABLE MATTER.
+
+In order to determine the unsaponifiable matter in fats and oils they
+are first saponified, then the unsaponifiable, which consists mainly of
+hydrocarbons and the higher alcohols cholesterol or phytosterol, is
+extracted with ether or petroleum ether, the ether evaporated and the
+residue weighed as unsaponifiable.
+
+To carry out the process first saponify about 5 grams of fat or oil with
+an excess of alcoholic potassium hydrate, 20-30 cubic centimeters of a 1
+to 10 solution of potassium hydroxide in alcohol until the alcohol is
+evaporated over a steam bath. Wash the soap thus formed into a
+separatory funnel of 200 cubic centimeters capacity with 80-100 cubic
+centimeters water. Then add about 60 cubic centimeters of ether,
+petroleum ether or 86 degs. gasoline and thoroughly shake the funnel to
+extract the unsaponifiable. Should the two layers not separate readily,
+add a few cubic centimeters of alcohol, which will readily cause them to
+separate. Draw off the watery solution from beneath and wash the ether
+with water containing a few drops of sodium hydrate and run to another
+dish. Pour the watery solution into the funnel again and repeat the
+extraction once or twice more or until the ether shows no discoloration.
+Combine the ether extractions into the funnel and wash with water until
+no alkaline reaction is obtained from the wash water. Run the ether
+extract to a weighed dish, evaporate and dry rapidly in a drying oven.
+As some of the hydrocarbons are readily volatile at 100 degs.
+Centigrade, the drying should not be carried on any longer than
+necessary. The residue is then weighed and the original weight of fat
+taken divided into the weight of the residue × 100 gives the percentage
+unsaponifiable.
+
+
+TEST FOR COLOR OF SOAP.
+
+It is often desirable to determine the color of the finished soap by a
+rapid determination before it is made into soap. It often happens,
+especially with the tallows, that a dark colored sample produces a light
+colored soap, whereas a bleached light colored tallow produces a soap
+off shade.
+
+To rapidly determine whether the color easily washes out of the tallow
+with lye, 100 cubic centimeters of tallow are saponified in an enameled
+or iron dish with 100 cubic centimeters of 21 degs. Baumé soda lye and
+100 cubic centimeters of denatured alcohol. Continue heating over a wire
+gauze until all the alcohol is expelled and then add 50 cubic
+centimeters of the 21 degs. Baumé lye to grain the soap. Allow the lyes
+to settle and with an inverted pipette draw off the lyes into a test
+tube or bottle. Close the soap with 100 cubic centimeters of hot water
+and when closed again grain with 50 cubic centimeters of the lye by just
+bringing to a boil over an open flame. Again allow the lyes to settle
+and put aside a sample of the lye for comparison. Repeat the process of
+closing, graining and settling and take a sample of lye. If the lye is
+still discolored repeat the above operations again or until the lye is
+colorless. Ordinarily all the color will come out with the third lye.
+The soap thus obtained contains considerable water which makes it appear
+white. The soap is, therefore, dried to about 15 per cent. moisture and
+examined for color. The color thus obtained is a very good criterion as
+to what may be expected in the soap kettle.
+
+By making the above analyses of fats or oils the main properties as to
+their adaptability for being made into soap are determined. In some
+cases, especially where adulteration or mixtures of oils are suspected,
+it is necessary to further analyze same. The methods of carrying out
+these analyses are fully covered by various texts on fats and oils and
+we will not go into details regarding the method of procedure in
+carrying these out.
+
+
+TESTING OF ALKALIS USED IN SOAP MAKING.
+
+The alkalis entering into the manufacture of soap such as caustic soda
+or sodium hydroxide, caustic potash or potassium hydrate, carbonate of
+soda or sodium carbonate, carbonate of potash or potassium carbonate
+usually contain impurities which do not enter into combination with the
+fats or fatty acids to form soap. It is out of the question to use
+chemically pure alkalis in soap making, hence it is often necessary to
+determine the alkalinity of an alkali. It may again be pointed out that
+in saponifying a neutral fat or oil only caustic soda or potash are
+efficient and the carbonate contained in these only combines to a more
+or less extent with any free fatty acids contained in the oils or fats.
+Caustic soda or potash or lyes made from these alkalis upon exposure to
+the air are gradually converted into sodium or potassium carbonate by
+the action of the carbon dioxide contained in the air. While the amount
+of carbonate thus formed is not very great and is greatest upon the
+surface, all lyes as well as caustic alkalis contain some carbonate.
+This carbonate introduces an error in the analysis of caustic alkalis
+when accuracy is required and thus in the analysis of caustic soda or
+potash it is necessary to remove the carbonate when the true alkalinity
+as sodium hydroxide or potassium hydroxide is desired. This may be done
+by titration in alcohol which has been neutralized.
+
+In order to determine the alkalinity of any of the above mentioned
+alkalis, it is first necessary to obtain a representative sample of the
+substance to be analyzed. To do this take small samples from various
+portions of the package and combine them into a composite sample.
+Caustic potash and soda are hygroscopic and samples should be weighed at
+once or kept in a well stoppered bottle. Sodium or potassium carbonate
+can be weighed more easily as they do not rapidly absorb moisture from
+the air.
+
+To weigh the caustic soda or potash place about five grams on a watch
+glass on a balance and weigh as rapidly as possible. Wash into a 500
+cubic centimeter volumetric flask and bring to the mark with distilled
+water. Pipette off 50 cubic centimeters into a 200 cubic centimeter
+beaker, dilute slightly with distilled water, add a few drops of methyl
+orange indicator and titrate with normal acid. For the carbonates about
+1 gram may be weighed, washed into a 400 cubic centimeter beaker,
+diluted with distilled water, methyl orange indicator added and titrated
+with normal acid. It is advisable to use methyl orange indicator in
+these titrations as phenolphthalein is affected by the carbon dioxide
+generated when an acid reacts with a carbonate and does not give the
+proper end point, unless the solution is boiled to expel the carbon
+dioxide. Litmus may also be used as the indicator, but here again it is
+necessary to boil as carbon dioxide also affects this substance. As an
+aid to the action of these common indicators the following table may be
+helpful:
+
+                    _Color in     _Color in
+  _Indicator._         Acid        Alkaline       _Action of
+                    Solution._     Solution._        CO_{2}._
+
+Methyl orange       Red             Yellow       Very slightly acid
+Phenolphthalein     Colorless       Red          Acid
+Litmus              Red             Blue         Acid
+
+It may be further stated that methyl orange at the neutral point is
+orange in color.
+
+To calculate the percentage of effective alkali from the above
+titrations, it must be first pointed out that in the case of caustic
+potash or soda aliquot portions are taken. This is done to reduce the
+error necessarily involved by weighing, as the absorption of water is
+decided. Thus we had, say, exactly 5 grams which weighed 5.05 grams by
+the time it was balanced. This was dissolved in 500 cubic centimeters of
+water and 50 cubic centimeters or one tenth of the amount of the
+solution was taken, or in each 50 cubic centimeters there were 0.505
+grams of the sample. We thus reduced the error of weighing by one tenth
+provided other conditions introduce no error. In the case of the
+carbonates the weight is taken directly.
+
+One cubic centimeter of a normal acid solution is the equivalent of:
+
+                                           Grams.
+    Sodium Carbonate, Na_{2}CO_{3}        0.05305
+    Sodium Hydroxide, NaOH                0.04006
+    Sodium Oxide, Na_{2}O                 0.02905
+    Carbonate K_{2}CO_{3}                 0.06908
+    Potassium Hydroxide, KOH              0.05616
+    Potassium Oxide, K_{2}O               0.04715
+
+Hence to arrive at the alkalinity we multiply the number of cubic
+centimeters, read on the burette, by the factor opposite the terms in
+which we desire to express the alkalinity, divide the weight in grams
+thus obtained by the original weight taken, and multiply the result by
+100, which gives the percentage of alkali in the proper terms. For
+example, say, we took the 0.505 grams of caustic potash as explained
+above and required 8.7 cubic centimeter normal acid to neutralize the
+solution, then
+
+    8.7 × .05616 = .4886 grams KOH in sample
+
+    .4886
+    ----- × 100 = 96.73% KOH in sample.
+    .505
+
+Caustic potash often contains some caustic soda, and while it is
+possible to express the results in terms of KOH, regardless of any
+trouble that may be caused by this mixture in soap making, an error is
+introduced in the results, not all the alkali being caustic potash. In
+such cases it is advisable to consult a book on analysis as the analysis
+is far more complicated than those given we will not consider it. The
+presence of carbonates, as already stated, also causes an error. To
+overcome this the alkali is titrated in absolute alcohol, filtering off
+the insoluble carbonate. The soluble portion is caustic hydrate and may
+be titrated as such. The carbonate remaining on the filter paper is
+dissolved in water and titrated as carbonate.
+
+
+SOAP ANALYSIS.
+
+To obtain a sample of a cake of soap for analysis is a rather difficult
+matter as the moisture content of the outer and inner layer varies
+considerably. To overcome this difficulty a borer or sampler may be run
+right through the cake of soap, or slices may be cut from various parts
+of the cake, or the cake may be cut and run through a meat chopper
+several times and mixed. A sufficient amount of a homogeneous sample
+obtained by any of these methods is preserved for the entire analysis by
+keeping the soap in a securely stoppered bottle.
+
+The more important determinations of soap are moisture, free alkali, or
+fatty acid, combined alkali and total fatty matter. Besides these it is
+often necessary to determine insoluble matter, glycerine, unsaponifiable
+matter, rosin and sugar.
+
+
+MOISTURE.
+
+The analysis of soap for moisture, at its best, is most unsatisfactory,
+for by heating it is impossible to drive off all the water, and on the
+other hand volatile oils driven off by heat are a part of the loss
+represented as moisture.
+
+The usual method of determining moisture is to weigh 2 to 3 grams of
+finely shaved soap on a watch glass and heat in an oven at 105 degrees
+C. for 2 to 3 hours. The loss in weight is represented as water,
+although it is really impossible to drive off all the water in this way.
+
+To overcome the difficulties just mentioned either the Smith or Fahrion
+method may be used. Allen recommends Smith's method which is said to be
+truthful to within 0.25 per cent. Fahrion's method, according to the
+author, gives reliable results to within 0.5 per cent. Both are more
+rapid than the above manipulation. To carry out the method of Smith, 5
+to 10 grams of finely ground soap are heated over a sand bath with a
+small Bunsen flame beneath it, in a large porcelain crucible. The
+heating takes 20 to 30 minutes, or until no further evidence is present
+of water being driven off. This may be tested by the fogging of a cold
+piece of glass held over the crucible immediately upon removing the
+burner. When no fog appears the soap is considered dry. Any lumps of
+soap may be broken up by a small glass rod, weighed with the crucible,
+and with a roughened end to more easily separate the lumps. Should the
+soap burn, this can readily be detected by the odor, which, of course,
+renders the analysis useless. The loss in weight is moisture.
+
+By Fahrion's method[13], 2 to 4 grams of soap are weighed in a platinum
+crucible and about three times its weight of oleic acid, which has been
+heated at 120 degrees C. until all the water is driven off and preserved
+from moisture, is added and reweighed. The dish is then cautiously
+heated with a small flame until all the water is driven off and all the
+soap is dissolved. Care must be exercised not to heat too highly or the
+oleic acid will decompose. The moment the water is all driven off a
+clear solution is formed, provided no fillers are present in the soap.
+The dish is then cooled in a dessicator and reweighed. The loss in
+weight of acid plus soap is moisture and is calculated on the weight of
+soap taken. This determination takes about fifteen minutes.
+
+
+FREE ALKALI OR ACID.
+
+(_a_) _Alcoholic Method._
+
+Test a freshly cut surface of the soap with a few drops of an alcoholic
+phenolphthalein solution. If it does not turn red it may be assumed free
+fat is present; should a red color appear, free alkali is present. In
+any case dissolve 2 to 5 grams of soap in 100 cubic centimeters of
+neutralized alcohol and heat to boiling until in solution. Filter off
+the undissolved portion containing carbonate, etc., and wash with
+alcohol. Add phenolphthalein to the filtrate and titrate with N/10 acid
+and calculate the per cent. of free alkali as sodium or potassium
+hydroxide. Should the filtrate be acid instead of alkaline, titrate with
+N/10 alkali and calculate the percentage of free fatty acid as oleic
+acid.
+
+The insoluble portion remaining on the filter paper is washed with water
+until all the carbonate is dissolved. The washings are then titrated
+with N/10 sulfuric acid and expressed as sodium or potassium carbonate.
+Should borates or silicates be present it is possible to express in
+terms of these. If borax is present the carbon dioxide is boiled off
+after neutralizing exactly to methyl orange; cool, add mannite and
+phenolphthalein and titrate the boric acid with standard alkali.
+
+(_b_) _Bosshard and Huggenberg Method._[14]
+
+In using the alcoholic method for the determination of the free alkali
+or fat in soap there is a possibility of both free fat and free alkali
+being present. Upon boiling in an alcoholic solution the fat will be
+saponified, thus introducing an error in the analysis. The method of
+Bosshard and Huggenberg overcomes this objection. Their method is
+briefly as follows:
+
+_Reagents._
+
+1. N/10 hydrochloric acid to standardize N/10 alcoholic sodium
+hydroxide.
+
+2. Approximately N/10 alcoholic sodium hydroxide to fix and control the
+N/40 stearic acid.
+
+3. N/40 stearic acid. Preparation: About 7.1 grams of stearic acid are
+dissolved in one liter of absolute alcohol, the solution filtered, the
+strength determined by titration against N/10 NaOH and then protected in
+a well stoppered bottle, or better still connected directly to the
+burette.
+
+4. A 10 per cent. solution of barium chloride. Preparation: 100 grams of
+barium chloride are dissolved in one liter of distilled water and
+filtered. The neutrality of the solution should be proven as it must be
+neutral.
+
+5. [Greek: alpha] naptholphthalein indicator according to Sorenson.
+Preparation: 0.1 gram of [Greek: alpha] naphtholphthalein is dissolved in
+150 cubic centimeters of alcohol and 100 cubic centimeters of water.
+For every 10 cubic centimeters of liquid use at least 12 drops of
+indicator.
+
+6. Phenolphthalein solution 1 gram to 100 cubic centimeter 96 per cent.
+alcohol.
+
+7. Solvent, 50 per cent. alcohol neutralized.
+
+
+MANIPULATION.
+
+First--Determine the strength of the N/10 alcoholic sodium hydroxide in
+terms of N/10 hydrochloric acid and calculate the factor, e. g.:
+
+    10 c.c. N/10 alcoholic NaOH = 9.95 N/10 HCl}
+    10 c.c. N/10 alcoholic NaOH = 9.96 N/10 HCl} 9.96
+
+The alcoholic N/10 NaOH has a factor of 0.996.
+
+Second--Control the N/40 stearic acid with the above alkali to obtain
+its factor, e. g.:
+
+    40 c.c. N/40 alcoholic stearic acid =
+                              10.18 c.c. N/10 NaOH }
+    40 c.c. N/40 alcoholic stearic acid =          } 10.2
+                              10.22 c.c. N/10 NaOH }
+
+    10.2 × F N/10 NaOH (0.996) = Factor N/40 stearic acid
+
+        Therefore Factor N/40 stearic acid = 1.016.
+
+Third--About 5 grams of soap are weighed and dissolved in 100 cubic
+centimeters of 50 per cent. neutralized alcohol in a 250 cubic
+centimeter Erlenmeyer flask over a water bath and connected with a
+reflux condensor. When completely dissolved, which takes but a few
+moments, it is cooled by allowing a stream of running water to run over
+the outside of the flask.
+
+Fourth--The soap is precipitated with 15 to 20 cubic centimeters of the
+10 per cent. barium chloride solution.
+
+Fifth--After the addition of 2 to 5 cubic centimeters of [Greek: alpha]
+naphtholphthalein solution the solution is titrated with N/40 alcoholic
+stearic acid. [Greek: alpha] naphtholphthalein is red with an excess of
+stearic acid. To mark the color changes it is advisable to first run a
+few blanks until the eye has become accustomed to the change in the
+indicator in the same way. The change from green to red can then be
+carefully observed.
+
+Let us presume 5 grams of soap were taken for the analysis and 20 cubic
+centimeters of N/40 stearic acid were required for the titration then to
+calculate the amount of NaOH since the stearic factor is 1.016.
+
+20 × 1.016 = 20.32 N/40 stearic acid really required.
+
+1 cubic centimeter N/40 stearic acid = 0.02 per cent. NaOH for 5 grams
+soap.
+
+[Greek: Delta] 20.32 cubic centimeters N/40 stearic acid = 0.02 × 20.32
+per cent. NaOH for 5 grams soap.
+
+Hence the soap contains 0.4064 per cent. NaOH.
+
+It is necessary, however, to make a correction by this method. When the
+free alkali amounts to over 0.1 per cent. the correction is + 0.01, and
+when the free alkali exceeds 0.4 per cent. the correction is + 0.04,
+hence in the above case we multiply 0.004064 by 0.04, add this amount to
+0.004064 and multiply by 100 to obtain the true percentage. Should the
+alkalinity have been near 0.1 per cent. we would have multiplied by 0.01
+and added this.
+
+If carbonate is also present in the soap, another 5 grams of soap is
+dissolved in 100 cubic centimeters of 50 per cent. alcohol and the
+solution titrated directly after cooling with N/40 stearic acid, using
+[Greek: alpha] naphtholphthalein or phenolphthalein as an indicator,
+without the addition of barium chloride. From the difference of the two
+titrations the alkali present as carbonate is determined.
+
+If the decomposed soap solution is colorless with phenolphthalein, free
+fatty acids are present, which may be quickly determined with alcoholic
+N/10 sodium hydroxide.
+
+
+INSOLUBLE MATTER.
+
+The insoluble matter in soap may consist of organic or inorganic
+substances. Among the organic substances which are usually present in
+soap are oat meal, bran, sawdust, etc., while among the common inorganic
+or mineral compounds are pumice, silex, clay, talc, zinc oxide,
+infusorial earth, sand or other material used as fillers.
+
+To determine insoluble matter, 5 grams of soap are dissolved in 75 cubic
+centimeters of hot water. The solution is filtered through a weighed
+gooch crucible or filter paper. The residue remaining on the filter is
+washed with hot water until all the soap is removed, is then dried to
+constant weight at 105 degrees C. and weighed. From the difference in
+weight of the gooch or filter paper and the dried residue remaining
+thereon after filtering and drying, the total percentage of insoluble
+matter may easily be calculated. By igniting the residue and reweighing
+the amount of insoluble mineral matter can be readily determined.
+
+
+STARCH AND GELATINE.
+
+Should starch or gelatine be present in soap it is necessary to extract
+5 grams of the soap with 100 cubic centimeters of 95 per cent.
+neutralized alcohol in a Soxhlet extractor until the residue on the
+extraction thimble is in a powder form. If necessary the apparatus
+should be disconnected and any lumps crushed, as these may contain soap.
+The residue remaining on the thimble consists of all substances present
+in soap, insoluble in alcohol. This is dried and weighed so that any
+percentage of impurities not actually determined can be found by
+difference. Starch and gelatine are separated from carbonate, sulfate
+and borate by dissolving the latter out through a filter with cold
+water. The starch and gelatine thus remaining can be determined by
+known methods, starch by the method of direct hydrolysis[15] and
+gelatine by Kjeldahling and calculating the corresponding amount of
+gelatine from the percentage of nitrogen (17.9%) therein.[16]
+
+
+TOTAL FATTY AND RESIN ACIDS.
+
+To the filtrate from the insoluble matter add 40 cubic centimeters of
+half normal sulfuric acid, all the acid being added at once. Boil, stir
+thoroughly for some minutes and keep warm on a water bath until the
+fatty acids have collected as a clear layer on the surface. Cool by
+placing the beaker in ice and syphon off the acid water through a
+filter. Should the fatty acids not readily congeal a weighed amount of
+dried bleached bees-wax or stearic acid may be added to the hot mixture.
+This fuses with the hot mass and forms a firm cake of fatty acids upon
+cooling. Without removing the fatty acids from the beaker, add about 300
+cubic centimeters of hot water, cool, syphon off the water through the
+same filter used before and wash again. Repeat washing, cooling and
+syphoning processes until the wash water is no longer acid. When this
+stage is reached, dissolve any fatty acid which may have remained on the
+filter with hot 95 per cent. alcohol into the beaker containing the
+fatty acids. Evaporate the alcohol and dry the beaker to constant weight
+over a water bath. The fatty acids thus obtained represent the combined
+fatty acids, uncombined fat and hydrocarbons.
+
+
+DETERMINATION OF ROSIN.
+
+If resin acids are present, this may be determined by the
+Liebermann-Storch reaction. To carry out this test shake 2 cubic
+centimeters of the fatty acids with 5 cubic centimeters of acetic
+anhydride; warm slightly; cool; draw off the anhydride and add 1:1
+sulfuric acid. A violet color, which is not permanent, indicates the
+presence of rosin in the soap. The cholesterol in linseed or fish oil,
+which of course may be present in the soap, also give this reaction.
+
+Should resin acids be present, these may be separated by the Twitchell
+method, which depends upon the difference in the behavior of the fatty
+and resin acids when converted into their ethyl esters through the
+action of hydrochloric acid. This may be carried out as follows:
+
+Three grams of the dried mixed acids are dissolved in 25 cubic
+centimeters of absolute alcohol in a 100 cubic centimeter stoppered
+flask; the flask placed in cold water and shaken. To this cooled
+solution 25 cubic centimeters of absolute alcohol saturated with dry
+hydrochloric acid is added. The flask is shaken occasionally and the
+action allowed to continue for twenty minutes, then 10 grams of dry
+granular zinc chloride are added, the flask shaken and again allowed to
+stand for twenty minutes. The contents of the flask are then poured into
+200 cubic centimeters of water in a 500 cubic centimeter beaker and the
+flask rinsed out with alcohol. A small strip of zinc is placed in the
+beaker and the alcohol evaporated. The beaker is then cooled and
+transferred to a separatory funnel, washing out the beaker with 50 cubic
+centimeters of gasoline (boiling below 80 degrees C.) and extracting by
+shaking the funnel well. Draw off the acid solution after allowing to
+separate and wash the gasoline with water until free from hydrochloric
+acid. Draw off the gasoline solution and evaporate the gasoline.
+Dissolve the residue in neutral alcohol and titrate with standard alkali
+using phenolphthalein as an indicator. One cubic centimeter of normal
+alkali equals 0.346 grams of rosin. The rosin may be gravimetrically
+determined by washing the gasoline extract with water, it not being
+necessary to wash absolutely free from acid, then adding 0.5 gram of
+potassium hydroxide and 5 cubic centimeters of alcohol in 50 cubic
+centimeters of water. Upon shaking the resin acids are rapidly
+saponified and extracted by the dilute alkaline solution as rosin soaps,
+while the ethyl esters remain in solution in the gasoline. Draw off the
+soap solution, wash the gasoline solution again with dilute alkali and
+unite the alkaline solutions. Decompose the alkaline soap solution with
+an excess of hydrochloric acid and weigh the resin acids liberated as in
+the determination of total fatty acids.
+
+According to Lewkowitsch, the results obtained by the volumetric method
+which assumes a combining weight of 346 for resin acids, are very likely
+to be high. On the other hand those obtained by the gravimetric method
+are too low.
+
+Leiste and Stiepel[17] have devised a simpler method for the
+determination of rosin. They make use of the fact that the resin acids
+as sodium soaps are soluble in acetone and particularly acetone
+containing two per cent. water, while the fatty acid soaps are soluble
+in this solvent to the extent of only about 2 per cent. First of all it
+is necessary to show that the sample to be analyzed contains a mixture
+of resin and fatty acids. This may be done by the Liebermann-Storch
+reaction already described. Glycerine interferes with the method. Two
+grams of fatty acids or 3 grams of soap are weighed in a nickel crucible
+and dissolved in 15-20 cubic centimeters of alcohol. The solution is
+then neutralized with alcoholic sodium hydroxide, using phenolphthalein
+as an indicator. The mass is concentrated by heat over an asbestos plate
+until a slight film forms over it. Then about 10 grams of sharp,
+granular, ignited sand are stirred in by means of a spatula, the alcohol
+further evaporated, the mixture being constantly stirred and then
+thoroughly dried in a drying oven. The solvent for the cooled mass is
+acetone containing 2 per cent. water. It is obtained from acetone dried
+by ignited sodium sulfate and adding 2 per cent. water by volume. One
+hundred cubic centimeters of this solvent are sufficient for extracting
+the above. The extraction of the rosin soap is conducted by adding 10
+cubic centimeters of acetone eight times, rubbing the mass thoroughly
+with a spatula and decanting. The decanted portions are combined in a
+beaker and the suspended fatty soaps allowed to separate. The mixture is
+then filtered into a previously weighed flask and washed several times
+with the acetone remaining. The solution of rosin soap should show no
+separation of solid matter after having evaporated to half the volume
+and allowing to cool. If a separation should occur another filtration
+and the slightest possible washing is necessary. To complete the
+analysis, the acetone is completely evaporated and the mass dried to
+constant weight in a drying oven. The weight found gives the weight of
+the rosin soap. In conducting the determination, it is important to dry
+the mixture of soap and sand thoroughly. In dealing with potash soaps it
+is necessary to separate the fatty acids from these and use them as
+acetone dissolves too great a quantity of a potash soap.
+
+
+TOTAL ALKALI.
+
+In the filtrate remaining after having washed the fatty acids in the
+determination of total fatty and resin acids all the alkali present as
+soap, as carbonate and as hydroxide remains in solution as sulfate. Upon
+titrating this solution with half normal alkali the difference between
+the half normal acid used in decomposing the soap and alkali used in
+titrating the excess of acid gives the amount of total alkali in the
+soap. By deducting the amount of free alkali present as carbonate or
+hydroxide previously found the amount of combined alkali in the soap may
+be calculated.
+
+To quickly determine total alkali in soap a weighed portion of the soap
+may be ignited to a white ash and the ash titrated for alkalinity using
+methyl orange as an indicator.
+
+
+UNSAPONIFIED MATTER.
+
+Dissolve 5 grams of soap in 50 cubic centimeters of 50 per cent.
+alcohol. Should any free fatty acids be present neutralize them with
+standard alkali. Wash into a separatory funnel with 50 per cent. alcohol
+and extract with 100 cubic centimeters of gasoline, boiling at 50
+degrees to 60 degrees C. Wash the gasoline with water, draw off the
+watery layer. Run the gasoline into a weighed dish, evaporate the
+alcohol, dry and weigh the residue as unsaponified matter. The residue
+contains any hydrocarbon oils or fats not converted into soap.
+
+
+SILICA AND SILICATES.
+
+The insoluble silicates, sand, etc., are present in the ignited residue
+in the determination of insoluble matter. Sodium silicate, extensively
+used as a filler, however, will only show itself in forming a pasty
+liquid. Where it is desired to determine sodium silicate, 10 grams of
+soap are ashed by ignition, hydrochloric acid added to the ash in excess
+and evaporated to dryness. More hydrochloric acid is then added and the
+mass is again evaporated until dry; then cooled; moistened with
+hydrochloric acid; dissolved in water; filtered; washed; the filtrate
+evaporated to dryness and again taken up with hydrochloric acid and
+water; filtered and washed. The precipitates are then combined and
+ignited. Silicon dioxide (SiO_{2}) is thus formed, which can be
+calculated to sodium silicate (Na_{2}Si_{4}O_{9}). Should other metals
+than alkali metals be suspected present the filtrate from the silica
+determinations should be examined.
+
+
+GLYCERINE IN SOAP.
+
+To determine the amount of glycerine contained in soap dissolve 25 grams
+in hot water, add a slight excess of sulfuric acid and keep hot until
+the fatty acids form as a clear layer on top. Cool the mass and remove
+the fatty acids. Filter the acid solution into a 25 cubic centimeter
+graduated flask; bring to the mark with water and determine the
+glycerine by the bichromate method as described under glycerine
+analysis.
+
+When sugar is present the bichromate would be reduced by the sugar,
+hence this method is not applicable. In this case remove the fatty acids
+as before, neutralize an aliquot portion with milk of lime, evaporate to
+10 cubic centimeters, add 2 grams of sand and milk of lime containing
+about 2 grams of calcium hydroxide and evaporate almost to dryness.
+Treat the moist residue with 5 cubic centimeters of 96 per cent.
+alcohol, rub the whole mass into a paste, then constantly stirring, heat
+on a water bath and decant into a 250 cubic centimeter graduated flask.
+Repeat the washing with 5 cubic centimeters of alcohol five or six
+times, each time pouring the washings into the flask; cool the flask to
+room temperature and fill to the mark with 96 per cent. alcohol, agitate
+the flask until well mixed and filter through a dry filter paper. Take
+200 cubic centimeters of the nitrate and evaporate to a syrupy
+consistency over a safety water bath. Wash the liquor into a stoppered
+flask with 20 cubic centimeters of absolute alcohol, add 30 cubic
+centimeters of absolute ether 10 cubic centimeters at a time, shaking
+well after each addition and let stand until clear. Pour off the
+solution through a filter into a weighed dish and wash out the flask
+with a mixture of three parts absolute ether and two parts absolute
+alcohol. Evaporate to a syrup, dry for one hour at the temperature of
+boiling water, weigh, ignite and weigh again. The loss is glycerine.
+This multiplied by 5/4 gives the total loss for the aliquot portion
+taken. The glycerine may also be determined by the acetin or bichromate
+methods after driving off the alcohol and ether if so desired.
+
+
+SUGAR IN SOAP.
+
+To determine sugar in soap, usually present in transparent soaps,
+decompose a soap solution of 5 grams of soap dissolved in 100 cubic
+centimeters of hot water with an excess of hydrochloric acid and
+separate the fatty acids as usual. Filter the acid solution into a
+graduated flask and make up to the mark. Take an aliquot containing
+approximately 1 per cent. of reducing sugar and determine the amount of
+sugar by the Soxhlet method.[18]
+
+
+GLYCERINE ANALYSIS.
+
+The methods of analyzing glycerine varied so greatly due to the fact
+that glycerine contained impurities which acted so much like glycerine
+as to introduce serious errors in the determinations of crude glycerine.
+This led to the appointment of committees in the United States and
+Europe to investigate the methods of glycerine analysis. An
+international committee met after their investigations and decided the
+acetin method should control the buying and selling of glycerine, but
+the more convenient bichromate method in a standardized form might be
+used in factory control and other technical purposes. The following are
+the methods of analysis and sampling as suggested by the international
+committee:
+
+
+SAMPLING.
+
+The most satisfactory method available for sampling crude glycerine
+liable to contain suspended matter, or which is liable to deposit salt
+on settling, is to have the glycerine sampled by a mutually approved
+sampler as soon as possible after it is filled into drums, but in any
+case before any separation of salt has taken place. In such cases he
+shall sample with a sectional sampler (see appendix) then seal the
+drums, brand them with a number for identification, and keep a record of
+the brand number. The presence of any visible salt or other suspended
+matter is to be noted by the sampler, and a report of the same made in
+his certificate, together with the temperature of the glycerine. Each
+drum must be sampled. Glycerine which has deposited salt or other solid
+matter cannot be accurately sampled from the drums, but an approximate
+sample can be obtained by means of the sectional sampler, which will
+allow a complete vertical section of the glycerine to be taken including
+any deposit.
+
+
+ANALYSIS.
+
+1. _Determination of Free Caustic Alkali._--Put 20 grams of the sample
+into a 100 cc. flask, dilute with approximately 50 cc. of freshly boiled
+distilled water, add an excess of neutral barium chloride solution, 1
+cc. of phenolphthalein solution, make up to the mark and mix. Allow the
+precipitate to settle, draw off 50 cc. of the clear liquid and titrate
+with normal acid (_N_/1). Calculate the percentage of Na_{2}O existing
+as caustic alkali.
+
+2. _Determination of Ash and Total Alkalinity._--Weigh 2 to 5 grams of
+the sample in a platinum dish, burn off the glycerine over a luminous
+Argand burner or other source of heat,[19] giving a low temperature, to
+avoid volatilization and the formation of sulphides. When the mass is
+charred to the point that water will not be colored by soluble organic
+matter, lixiviate with hot distilled water, filter, wash and ignite the
+residue in the platinum dish. Return the filtrate and washings to the
+dish, evaporate the water, and carefully ignite without fusion. Weigh
+the ash.
+
+Dissolve the ash in distilled water and titrate total alkalinity, using
+as indicator methyl orange cold or litmus boiling.
+
+3. _Determination of Alkali Present as Carbonate._--Take 10 grams of the
+sample, dilute with 50 cc. distilled water, add sufficient _N_/1 acid to
+neutralize the total alkali found at (2), boil under a reflux condenser
+for 15 to 20 minutes, wash down the condenser tube with distilled water,
+free from carbon dioxide, and then titrate back with _N_/1 NaOH, using
+phenolphthalein as indicator. Calculate the percentage of Na_{2}O.
+Deduct the Na_{2}O found in (1). The difference is the percentage of
+Na_{2}O existing as carbonate.
+
+4. _Alkali Combined with Organic Acids._--The sum of the percentages of
+Na_{2}O found at (1) and (3) deducted from the percentage found at (2)
+is a measure of the Na_{2}O or other alkali combined with organic acids.
+
+5. _Determination of Acidity._--Take 10 grams of the sample, dilute with
+50 cc. distilled water free from carbon dioxide, and titrate with _N_/1
+NaOH and phenolphthalein. Express in terms of Na_{2}O required to
+neutralize 100 grams.
+
+6. _Determination of Total Residue at 160° C._--For this determination
+the crude glycerine should be slightly alkaline with Na_{2}CO_{3} not
+exceeding 0.2 per cent. Na_{2}O, in order to prevent loss of organic
+acids. To avoid the formation of polyglycerols this alkalinity must not
+be exceeded.
+
+Ten grams of the sample are put into a 100 cc. flask, diluted with water
+and the calculated quantity of _N_/1 HCl or Na_{2}CO_{3} added to give
+the required degree of alkalinity. The flask is filled to 100 cc., the
+contents mixed, and 10 cc. measured into a weighed Petrie or similar
+dish 2.5 in. in diameter and 0.5 in. deep, which should have a flat
+bottom. In the case of crude glycerine abnormally high in organic
+residue a smaller amount should be taken, so that the weight of the
+organic residue does not materially exceed 30 to 40 milligrams.
+
+The dish is placed on a water bath (the top of the 160° oven acts
+equally well) until most of the water has evaporated. From this point
+the evaporation is effected in the oven. Satisfactory results are
+obtained in an oven[20] measuring 12 ins. cube, having an iron plate
+0.75 in. thick lying on the bottom to distribute the heat. Strips of
+asbestos millboard are placed on a shelf half way up the oven. On these
+strips the dish containing the glycerine is placed.
+
+If the temperature of the oven has been adjusted to 160° C. with the
+door closed, a temperature of 130° to 140° can be readily maintained
+with the door partially open, and the glycerine, or most of it, should
+be evaporated off at this temperature. When only a slight vapor is seen
+to come off, the dish is removed and allowed to cool.
+
+An addition of 0.5 to 1.0 cc. of water is made, and by a rotary motion
+the residue brought wholly or nearly into solution. The dish is then
+allowed to remain on a water bath or top of the oven until the excess
+water has evaporated and the residue is in such a condition that on
+returning to the oven at 160° C. it will not spurt. The time taken up to
+this point cannot be given definitely, nor is it important. Usually two
+or three hours are required. From this point, however, the schedule of
+time must be strictly adhered to. The dish is allowed to remain in the
+oven, the temperature of which is carefully maintained at 160° C. for
+one hour, when it is removed, cooled, the residue treated with water,
+and the water evaporated as before. The residue is then subjected to a
+second baking of one hour, after which the dish is allowed to cool in a
+desiccator over sulphuric acid and weighed. The treatment with water,
+etc., is repeated until a constant loss of 1 to 1.5 mg. per hour is
+obtained.
+
+In the case of acid glycerine a correction must be made for the alkali
+added 1 cc. _N_/1 alkali represents an addition of 0.03 gram. In the
+case of alkaline crudes a correction should be made for the acid added.
+Deduct the increase in weight due to the conversion of the NaOH and
+Na_{2}CO_{3} to NaCl. The corrected weight multiplied by 100 gives the
+percentage of _total residue at 160° C._
+
+This residue is taken for the determination of the non-volatile
+acetylizable impurities (see acetin method).
+
+7. _Organic residue._--Subtract the ash from the total residue at 160°
+C. Report as organic residue at 160° C. (it should be noted that
+alkaline salts of fatty acids are converted to carbonates on ignition
+and that the CO_{3} thus derived is not included in the organic
+residue).
+
+
+ACETIN PROCESS FOR THE DETERMINATION OF GLYCEROL.
+
+This process is the one agreed upon at a conference of delegates from
+the British, French, German and American committees, and has been
+confirmed by each of the above committees as giving results nearer to
+the truth than the bichromate method on crudes in general. It is the
+process to be used (if applicable) whenever only one method is employed.
+On pure glycerines the results are identical with those obtained by the
+bichromate process. For the application of this method the crude
+glycerine should not contain over 60 per cent. water.
+
+
+REAGENTS REQUIRED.
+
+(_A_) _Best Acetic Anhydride._--This should be carefully selected. A
+good sample must not require more than 0.1 cc. normal NaOH for
+saponification of the impurities when a blank is run on 7.5 cc. Only a
+slight color should develop during digestion of the blank.
+
+The anhydride may be tested for strength by the following method: Into a
+weighed stoppered vessel, containing 10 to 20 cc. of water, run about 2
+cc. of the anhydride, replace the stopper and weigh. Let stand with
+occasional shaking, for several hours, to permit the hydrolysis of all
+the anhydride; then dilute to about 200 cc., add phenolphthalein and
+titrate with _N_/1 NaOH. This gives the total acidity due to free acetic
+acid and acid formed from the anhydride. It is worthy of note that in
+the presence of much free anhydride a compound is formed with
+phenolphthalein, soluble in alkali and acetic acid, but insoluble in
+neutral solutions. If a turbidity is noticed toward the end of the
+neutralization it is an indication that the anhydride is incompletely
+hydrolyzed and inasmuch as the indicator is withdrawn from the solution,
+results may be incorrect.
+
+Into a stoppered weighing bottle containing a known weight of recently
+distilled aniline (from 10 to 20 cc.) measure about 2 cc. of the sample,
+stopper, mix, cool and weigh. Wash the contents into about 200 cc. of
+cold water, and titrate the acidity as before. This yields the acidity
+due to the original, preformed, acetic acid plus one-half the acid due
+to anhydride (the other half having formed acetanilide); subtract the
+second result from the first (both calculated to 100 grams) and double
+the result, obtaining the cc. _N_/1 NaOH per 100 grams of the sample. 1
+cc. _N_/NaOH equals 0.0510 anhydride.
+
+(_B_) _Pure Fused Sodium Acetate._--The purchased salt is again
+completely fused in a platinum, silica or nickel dish, avoiding
+charring, powdered quickly and kept in a stoppered bottle or desiccator.
+It is most important that the sodium acetate be anhydrous.
+
+(_C_) _A Solution of Caustic Soda for Neutralizing, of about N_/1
+_Strength, Free from Carbonate._--This can be readily made by dissolving
+pure sodium hydroxide in its own weight of water (preferably water free
+from carbon dioxide) and allowing to settle until clear, or filtering
+through an asbestos or paper filter. The clear solution is diluted with
+water free from carbon dioxide to the strength required.
+
+(_D_) _N_/1 _Caustic Soda Free from Carbonate._--Prepared as above and
+carefully standardized. Some caustic soda solutions show a marked
+diminution in strength after being boiled; such solutions should be
+rejected.
+
+(_E_) _N_/1 _Acid._--Carefully standardized.
+
+(_F_) _Phenolphthalein Solution._--0.5 per cent. phenolphthalein in
+alcohol and neutralized.
+
+
+THE METHOD.
+
+In a narrow-mouthed flask (preferably round-bottomed), capacity about
+120 cc., which has been thoroughly cleaned and dried, weigh accurately
+and as rapidly as possible 1.25 to 1.5 grams of the glycerine. A Grethan
+or Lunge pipette will be found convenient. Add about 3 grams of the
+anhydrous sodium acetate, then 7.5 cc. of the acetic anhydride, and
+connect the flask with an upright Liebig condenser. For convenience the
+inner tube of this condenser should not be over 50 cm. long and 9 to 10
+mm. inside diameter. The flask is connected to the condenser by either a
+ground glass joint (preferably) or a rubber stopper. If a rubber stopper
+is used it should have had a preliminary treatment with hot acetic
+anhydride vapor.
+
+Heat the contents and keep just boiling for one hour, taking precautions
+to prevent the salts drying on the sides of the flask.
+
+Allow the flask to cool somewhat, and through the condenser tube add 50
+cc. of distilled water free from carbon dioxide at a temperature of
+about 80° C., taking care that the flask is not loosened from the
+condenser. The object of cooling is to avoid any sudden rush of vapors
+from the flask on adding water, and to avoid breaking the flask. Time is
+saved by adding the water before the contents of the flask solidify, but
+the contents may be allowed to solidify and the test proceeded with the
+next day without detriment, bearing in mind that the anhydride in excess
+is much more effectively hydrolyzed in hot than in cold water. The
+contents of the flask may be warmed to, but must not exceed, 80° C.,
+until the solution is complete, except a few dark flocks representing
+organic impurities in the crude. By giving the flask a rotary motion,
+solution is more quickly effected.
+
+Cool the flask and contents without loosening from the condenser. When
+quite cold wash down the inside of the condenser tube, detach the flask,
+wash off the stopper or ground glass connection into the flask, and
+filter the contents through an acid-washed filter into a Jena glass
+flask of about 1 litre capacity. Wash thoroughly with cold distilled
+water free from carbon dioxide. Add 2 cc. of phenolphthalein solution
+(_F_), then run in caustic soda solution (_C_) or (_D_) until a faint
+pinkish yellow color appears throughout the solution. This
+neutralization must be done most carefully; the alkali should be run
+down the sides of the flask, the contents of which are kept rapidly
+swirling with occasional agitation or change of motion until the
+solution is nearly neutralized, as indicated by the slower disappearance
+of the color developed locally by the alkali running into the mixture.
+When this point is reached the sides of the flask are washed down with
+carbon dioxide-free water and the alkali subsequently added drop by
+drop, mixing after each drop until the desired tint is obtained.
+
+Now run in from a burette 50 cc. or a calculated excess of _N_/1 NaOH
+(_D_) and note carefully the exact amount. Boil gently for 15 minutes,
+the flask being fitted with a glass tube acting as a partial condenser.
+Cool as quickly as possible and titrate the excess of NaOH with _N_/1
+acid (_E_) until the pinkish yellow or chosen end-point color just
+remains.[21] A further addition of the indicator at this point will
+cause an increase of the pink color; this must be neglected, and the
+first end-point taken.
+
+From the _N_/1 NaOH consumed calculate the percentage of glycerol
+(including acetylizable impurities) after making the correction for the
+blank test described below.
+
+1 cc. _N_/1 NaOH = 0.03069 gram glycerol.
+
+The coefficient of expansion for normal solutions is 0.00033 per cc.
+for each degree centigrade. A correction should be made on this account
+if necessary.
+
+_Blank Test._--As the acetic anhydride and sodium acetate may contain
+impurities which affect the result, it is necessary to make a blank
+test, using the same quantities of acetic anhydride, sodium acetate and
+water as in the analysis. It is not necessary to filter the solution of
+the melt in this case, but sufficient time must be allowed for the
+hydrolysis of the anhydride before proceeding with the neutralization.
+After neutralization it is not necessary to add more than 10 cc. of the
+_N_/1 alkali (_D_), as this represents the excess usually present after
+the saponification of the average soap lye crude. In determining the
+acid equivalent of the _N_/1 NaOH, however, the entire amount taken in
+the analysis, 50 cc., should be titrated after dilution with 300 cc.
+water free from carbon dioxide and without boiling.
+
+_Determination of the Glycerol Value of the Acetylizable
+Impurities._--The total residue at 160° C. is dissolved in 1 or 2 cc. of
+water, washed into the acetylizing flask and evaporated to dryness. Then
+add anhydrous sodium acetate and acetic anhydride in the usual amounts
+and proceed as described in the regular analysis. After correcting for
+the blank, calculate the result to glycerol.
+
+
+WAYS OF CALCULATING ACTUAL GLYCEROL CONTENT.
+
+(1) Determine the apparent percentage of glycerol in the sample by the
+acetin process as described. The result will include acetylizable
+impurities if any are present.
+
+(2) Determine the total residue at 160° C.
+
+(3) Determine the acetin value of the residue at (2) in terms of
+glycerol.
+
+(4) Deduct the result found at (3) from the percentage obtained at (1)
+and report this corrected figure as glycerol. If volatile acetylizable
+impurities are present these are included in this figure.
+
+Trimethyleneglycol is more volatile than glycerine and can therefore be
+concentrated by fractional distillation. An approximation to the
+quantity can be obtained from the spread between the acetin and
+bichromate results on such distillates. The spread multiplied by 1.736
+will give the glycol.
+
+
+BICHROMATE PROCESS FOR GLYCEROL DETERMINATION. REAGENTS REQUIRED.
+
+(_A_) _Pure potassium bichromate_ powdered and dried in air free from
+dust or organic vapors, at 110° to 120° C. This is taken as the
+standard.
+
+(_B_) _Dilute Bichromate Solution._--7.4564 grams of the above
+bichromate are dissolved in distilled water and the solution made up to
+one liter at 15.5° C.
+
+(_C_) _Ferrous Ammonium Sulphate._--It is never safe to assume this salt
+to be constant in composition and it must be standardized against the
+bichromate as follows: dissolve 3.7282 grams of bichromate (_A_) in 50
+cc. of water. Add 50 cc. of 50 per cent. sulphuric acid (by volume), and
+to the cold undiluted solution add from a weighing bottle a moderate
+excess of the ferrous ammonium sulphate, and titrate back with the
+dilute bichromate (_B_). Calculate the value of the ferrous salt in
+terms of bichromate.
+
+(_D_) _Silver Carbonate._--This is prepared as required for each test
+from 140 cc. of 0.5 per cent. silver sulphate solution by precipitation,
+with about 4.9 cc. _N_/1 sodium carbonate solution (a little less than
+the calculated quantity of _N_/1 sodium carbonate should be used as an
+excess to prevent rapid settling). Settle, decant and wash one by
+decantation.
+
+(_E_) _Subacetate of Lead._--Boil a 10 per cent. solution of pure lead
+acetate with an excess of litharge for one hour, keeping the volume
+constant, and filter while hot. Disregard any precipitate which
+subsequently forms. Preserve out of contact with carbon dioxide.
+
+(_F_) _Potassium Ferricyanide._--A very dilute, freshly prepared
+solution containing about 0.1 per cent.
+
+
+THE METHOD.
+
+Weigh 20 grams of the glycerine, dilute to 250 cc. and take 25 cc. Add
+the silver carbonate, allow to stand, with occasional agitation, for
+about 10 minutes, and add a slight excess (about 5 cc. in most cases) of
+the basic lead acetate (_E_), allow to stand a few minutes, dilute with
+distilled water to 100 cc., and then add 0.15 cc. to compensate for the
+volume of the precipitate, mix thoroughly, filter through an air-dry
+filter into a suitable narrow-mouthed vessel, rejecting the first 10
+cc., and return the filtrate if not clear and bright. Test a portion of
+the filtrate with a little basic lead acetate, which should produce no
+further precipitate (in the great majority of cases 5 cc. are ample, but
+occasionally a crude will be found requiring more, and in this case
+another aliquot of 25 cc. of the dilute glycerine should be taken and
+purified with 6 cc. of the basic acetate). Care must be taken to avoid a
+marked excess of basic acetate.
+
+Measure off 25 cc. of the clear filtrate into a flask or beaker
+(previously cleaned with potassium bichromate and sulphuric acid). Add
+12 drops of sulphuric acid (1: 4) to precipitate the small excess of
+lead as sulphate. Add 3.7282 grams of the powdered potassium bichromate
+(_A_). Rinse down the bichromate with 25 cc. of water and let stand with
+occasional shaking until all the bichromate is dissolved (no reduction
+will take place in the cold).
+
+Now add 50 cc. of 50 per cent. sulphuric acid (by volume) and immerse
+the vessel in boiling water for two hours and keep protected from dust
+and organic vapors, such as alcohol, till the titration is completed.
+Add from a weighing bottle a slight excess of the ferrous ammonium
+sulphate (_C_), making spot tests on a porcelain plate with the
+potassium ferricyanide (_F_). Titrate back with the dilute bichromate.
+From the amount of bichromate reduced calculate the percentage of
+glycerol.
+
+1 gram glycerol = 7.4564 grams bichromate.
+
+1 gram bichromate = 0.13411 gram glycerol.
+
+The percentage of glycerol obtained above includes any oxidizable
+impurities present after the purification. A correction for the
+non-volatile impurities may be made by running a bichromate test on the
+residue at 160° C.
+
+
+NOTES.
+
+(1) It is important that the concentration of acid in the oxidation
+mixture and the time of oxidation should be strictly adhered to.
+
+(2) Before the bichromate is added to the glycerine solution it is
+essential that the slight excess of lead be precipitated with sulphuric
+acid, as stipulated.
+
+(3) For crudes practically free from chlorides the quantity of silver
+carbonate may be reduced to one-fifth and the basic lead acetate to 0.5
+cc.
+
+(4) It is sometimes advisable to add a little potassium sulphate to
+insure a clear filtrate.
+
+
+SAMPLING CRUDE GLYCERINE.
+
+The usual method of sampling crude glycerine hitherto has been by means
+of a glass tube, which is slowly lowered into the drum with the object
+of taking as nearly as possible a vertical section of the glycerine
+contained in the drum. This method has been found unsatisfactory, owing
+to the fact that in cold climates glycerine runs into the tube very
+slowly, so that, owing to the time occupied, it is impossible to take a
+complete section of the crude. Another objection to the glass tube is
+that it fails to take anything approaching a correct proportion of any
+settled salt contained in the drum.
+
+The sampler which is illustrated herewith has been devised with the
+object of overcoming the objections to the glass tube as far as
+possible. It consists of two brass tubes, one fitting closely inside the
+other. A number of ports are cut out in each tube in such a way that
+when the ports are opened a continuous slot is formed which enables a
+complete section to be taken throughout the entire length of the drum.
+By this arrangement the glycerine fills into the sampler almost
+instantaneously. There are a number of ports cut at the bottom of the
+sampler which render it possible to take a proportion of the salt at the
+bottom of the drum. The instrument is so constructed that all the ports,
+including the bottom ones, can be closed simultaneously by the simple
+action of turning the handle at the top; a pointer is arranged which
+indicates on a dial when the sampler is open or closed. In samplers of
+larger section (1 in.) it is possible to arrange a third motion whereby
+the bottom ports only are open for emptying, but in samplers of smaller
+dimensions (5/8 in.) this third motion must be dispensed with, otherwise
+the dimensions of the ports have to be so small that the sampler would
+not be efficient.
+
+In using the sampler it is introduced into the drum with the ports
+closed, and when it has touched the bottom, the ports are opened for a
+second or two, then closed and withdrawn, and the sample discharged into
+the receiving vessel by opening the ports. When the drum contains salt
+which has deposited, the ports must be opened before the sampler is
+pushed through the salt, thus enabling a portion to be included in the
+sample. It is, however, almost impossible to obtain a correct proportion
+of salt after it has settled in the drum and it is therefore recommended
+that the drum be sampled before any salt has deposited. A sampler 1 in.
+in diameter withdraws approximately 10 oz. from a 110-gal. drum. A
+sampler 5/8 in. in diameter will withdraw about 5 oz.
+
+FOOTNOTES:
+
+[13] Zeit. Angew. Chem. 19, 385 (1906).
+
+[14] Zeit. Angew. Chem. 27, 11-20 (1914).
+
+[15] Bull. 107, Bur. Chem. U. S. Dept. Agriculture.
+
+[16] Richards and Gies, Am. J. Physiol. (1902) 7, 129.
+
+[17] Seifensieder Ztg. (1913) No. 46.
+
+[18] Bull 107, Bur. Chem. U. S. Dept. Agriculture.
+
+[19] Carbon is readily burned off completely, without loss of chlorides,
+in a gas-heated muffle furnace adjusted to a dull red heat.
+
+[20] An electric oven suitable for this work, which is readily adjusted
+to 160 degs. C., has been made for Mr. Low and the chairman, by the
+Apparatus and Specialty Company, Lansing, Mich. Its size is 9-1/2 × 10 ×
+16 inches, and capacity 8 Petrie dishes. It gives a strong draft at
+constant temperature.
+
+[21] A precipitate at this point is an indication of the presence of
+iron or alumina, and high results will be obtained unless a correction
+is made as described below.
+
+
+
+
+CHAPTER VII
+
+Standard Methods for the Sampling and Analysis of Commercial Fats and
+Oils[22]
+
+
+The following report of the _Committee on Analysis of Commercial Fats
+and Oils_ of the _Division of Industrial Chemists and Chemical
+Engineers_ of the American Chemical Society was adopted April 14, 1919,
+by unanimous vote:
+
+W. D. RICHARDSON, _Chairman_,
+Swift and Co., Chicago, Ill.
+
+R. W. BAILEY,
+Stillwell and Gladding, New York City.
+
+W. J. GASCOYNE,
+W. J. Gascoyne and Co., Baltimore, Md.
+
+I. KATZ,[A]
+Wilson and Co., Chicago, Ill.
+
+A. LOWENSTEIN,[A]
+Morris and Co., Chicago, Ill.
+
+H. J. MORRISON,
+Proctor and Gamble Co.,
+Ivorydale, Ohio.
+
+J. R. POWELL,
+Armour Soap Works, Chicago, Ill.
+
+R. J. QUINN,[A]
+Midland Chemical Co., Argo, Ill.
+
+PAUL RUDNICK,
+Armour and Co., Chicago, Ill.
+
+L. M. TOLMAN,
+Wilson and Co., Chicago, Ill.
+
+E. TWITCHELL,[A]
+Emery Candle Co., Cincinnati, Ohio.
+
+J. J. VOLLERTSEN,
+Morris and Co., Chicago, Ill.
+
+[Note A: Resigned.]
+
+
+Scope, Applicability and Limitations of the Methods.
+
+
+SCOPE.
+
+These methods are intended to aid in determining the commercial
+valuation of fats and fatty oils in their purchase and sale, based on
+the fundamental assumption commonly recognized in the trade, namely,
+that the product is true to name and is not adulterated. For methods for
+determining the identity of oils and fats, the absence of adulterants
+therein and for specific tests used in particular industries, the
+chemist is referred to standard works on the analysis of fats and oils.
+
+
+APPLICABILITY.
+
+The methods are applicable in commercial transactions involving fats and
+fatty oils used in the soap, candle and tanning industries, to edible
+fats and oils and to fats and fatty oils intended for lubricating and
+burning purposes. The methods are applicable to the raw oils used in the
+varnish and paint industry with the exceptions noted under limitations,
+but special methods have not been included.
+
+
+LIMITATIONS.
+
+The methods have not been developed with special reference to waxes
+(beeswax, carnauba wax, wool wax, etc.) although some of them may be
+found applicable to these substances. The Committee considers the Wijs
+method superior to the Hanus method for the determination of iodine
+number of linseed oil as well as other oils, although the Hanus method
+has been considered standard for this work for some time and has been
+adopted by the American Society for Testing Materials and in various
+specifications. It has been customary to use the Hübl method for the
+determination of iodine value of tung oil (China wood oil) but the
+Committee's work indicates that the Wijs method is satisfactory for this
+determination.
+
+
+Sampling.
+
+
+TANK CARS.
+
+1. SAMPLING WHILE LOADING--Sample shall be taken at discharge of pipe
+where it enters tank car dome. The total sample taken shall be not less
+than 50 lbs. and shall be a composite of small samples of about 1 pound
+each, taken at regular intervals during the entire period of loading.
+
+The sample thus obtained is thoroughly mixed and uniform 3-lb. portions
+placed in air-tight 3-lb. metal containers. At least three such samples
+shall be put up, one for the buyer, one for the seller, and the third to
+be sent to a referee chemist in case of dispute. All samples are to be
+promptly and correctly labeled and sealed.
+
+2. SAMPLING FROM CAR ON TRACK[23]--(_a_) _When contents are solid._[24]
+In this case the sample is taken by means of a large tryer measuring
+about 2 in. across and about 1-1/2 times the depth of the car in length.
+Several tryerfuls are taken vertically and obliquely toward the ends of
+the car until 50 lbs. are accumulated, when the sample is softened,
+mixed and handled as under (1). In case the contents of the tank car
+have assumed a very hard condition, as in Winter weather, so that it is
+impossible to insert the tryer, and it becomes necessary to soften the
+contents of the car by means of the closed steam coil (in nearly all
+tank cars the closed steam coil leaks) or by means of open steam in
+order to draw a proper sample, suitable arrangements must be made
+between buyer and seller for the sampling of the car after it is
+sufficiently softened, due consideration being given to the possible
+presence of water in the material in the car as received and also to the
+possible addition of water during the steaming. The Committee knows of
+no direct method for sampling a hard-frozen tank car of tallow in a
+satisfactory manner.
+
+(_b_) _When contents are liquid._ The sample taken is to be a 50-lb.
+composite made up of numerous small samples taken from the top, bottom
+and intermediate points by means of a bottle or metal container with
+removable stopper or top. This device attached to a suitable pole is
+lowered to the various desired depths, when the stopper or top is
+removed and the container allowed to fill. The 50-lb. sample thus
+obtained is handled as under (1).
+
+In place of the device described above, any sampler capable of taking a
+sample from the top, bottom, and center, or from a section through car,
+may be used.
+
+(_c_) _When contents are in semi-solid condition, or when stearine has
+separated from liquid portions._ In this case, a combination of (_a_)
+and (_b_) may be used or by agreement of the parties the whole may be
+melted and procedure (_b_) followed.
+
+
+BARRELS, TIERCES, CASKS, DRUMS, AND OTHER PACKAGES.
+
+All packages shall be sampled, unless by special agreement the parties
+arrange to sample a lesser number; but in any case not less than 10 per
+cent of the total number shall be sampled. The total sample taken shall
+be at least 20 lbs. in weight for each 100 barrels, or equivalent.
+
+1. BARRELS, TIERCES AND CASKS--(_a_) _When contents are solid._ The
+small samples shall be taken by a tryer through the bunghole or through
+a special hole bored in the head or side for the purpose, with a 1-in.
+or larger auger. Care should be taken to avoid and eliminate all borings
+and chips from the sample. The tryer is inserted in such a way as to
+reach the head of the barrel, tierce, or cask. The large sample is
+softened, mixed and handled according to TANK CARS (1).
+
+(_b_) _When contents are liquid._ In this case use is made of a glass
+tube with constricted lower end. This is inserted slowly and allowed to
+fill with the liquid, when the upper end is closed and the tube
+withdrawn, the contents being allowed to drain into the sample
+container. After the entire sample is taken it is thoroughly mixed and
+handled according to TANK CARS (1).
+
+(_c_) _When contents are semi-solid._ In this case the tryer or a glass
+tube with larger outlet is used, depending on the degree of fluidity.
+
+(_d_) _Very hard materials, such as natural and artificial stearines._
+By preference the barrels are stripped and samples obtained by breaking
+up contents of at least 10 per cent of the packages. This procedure is
+to be followed also in the case of cakes shipped in sacks. When shipped
+in the form of small pieces in sacks they can be sampled by grab
+sampling and quartering. In all cases the final procedure is as outlined
+under TANK CARS (1).
+
+2. DRUMS--Samples are to be taken as under (1), use being made of the
+bunghole. The tryer or tube should be sufficiently long to reach to the
+ends of the drum.
+
+3. OTHER PACKAGES--Tubs, pails and other small packages not mentioned
+above are to be sampled by tryer or tube (depending on fluidity) as
+outlined above, the tryer or tube being inserted diagonally whenever
+possible.
+
+4. MIXED LOTS AND PACKAGES--When lots of tallow or other fats are
+received in packages of various shapes and sizes, and especially wherein
+the fat itself is of variable composition, such must be left to the
+judgment of the sampler. If variable, the contents of each package
+should be mixed as thoroughly as possible and the amount of the
+individual samples taken made proportional to the sizes of the packages.
+
+
+Analysis.
+
+
+SAMPLE.
+
+The sample must be representative and at least three pounds in weight
+and taken in accordance with the STANDARD METHODS FOR THE SAMPLING OF
+COMMERCIAL FATS AND OILS. It must be kept in an air-tight container, in
+a dark, cool place.
+
+Soften the sample if necessary by means of a gentle heat, taking care
+not to melt it. When sufficiently softened, mix the sample thoroughly by
+means of a mechanical egg beater or other equally effective mechanical
+mixer.
+
+
+MOISTURE AND VOLATILE MATTER.
+
+APPARATUS: _Vacuum Oven_--The Committee Standard Oven.
+
+DESCRIPTION--The Standard F. A. C. Vacuum Oven has been designed with
+the idea of affording a simple and compact vacuum oven which will give
+as uniform temperatures as possible on the shelf. As the figure shows,
+it consists of an iron casting of rectangular sections with hinged front
+door made tight by means of a gasket and which can be lowered on opening
+the oven so as to form a shelf on which samples may be rested. The oven
+contains but one shelf which is heated from above as well as below by
+means of resistance coils. Several thermometer holes are provided in
+order to ascertain definitely the temperature at different points on the
+shelf. In a vacuum oven where the heating is done almost entirely by
+radiation it is difficult to maintain uniform temperatures at all
+points, but the F. A. C. oven accomplishes this rather better than most
+vacuum ovens. Larger ovens containing more than one shelf have been
+tried by the Committee, but have been found to be lacking in temperature
+uniformity and means of control. The entire oven is supported by means
+of a 4-in. standard pipe which screws into the base of the oven and
+which in turn is supported by being screwed into a blind flange of
+suitable diameter which rests on the floor or work table.
+
+_Moisture Dish_--A shallow, glass dish, lipped, beaker form,
+approximately 6 to 7 cm. diameter and 4 cm. deep, shall be standard.
+
+DETERMINATION--Weigh out 5 grams (= 0.2 g. of the prepared sample) into
+a moisture dish. Dry to constant weight in _vacuo_ at a uniform
+temperature, not less than 15° C. nor more than 20° C. above the boiling
+point of water at the working pressure, which must not exceed 100 mm. of
+mercury.[25] Constant weight is attained when successive dryings for
+1-hr. periods show an additional loss of not more that 0.05 per cent.
+Report loss in weight as MOISTURE AND VOLATILE MATTER.[26]
+
+[Illustration: STANDARD VACUUM OVEN]
+
+The vacuum-oven method cannot be considered accurate in the case of fats
+of the coconut oil group containing free acid and the Committee
+recommends that it be used only for oils of this group when they contain
+less than 1 per cent free acid. In the case of oils of this group
+containing more than 1 per cent free acid, recourse should be had
+temporarily to the routine control method for moisture and volatile
+matter[27] until the Committee develops a more satisfactory method.
+
+The air-oven method cannot be considered even approximately accurate in
+the case of the drying and semi-drying oils and those of the coconut oil
+group. Therefore, in the case of such oils as cottonseed oil, maize oil
+(corn oil), soy bean oil, linseed oil, coconut oil, palm kernel oil,
+etc., the vacuum-oven method should always be used, except in the case
+of fats of the coconut group containing more than 1 per cent free acid,
+as noted above.
+
+
+INSOLUBLE IMPURITIES.
+
+Dissolve the residue from the moisture and volatile matter determination
+by heating it on a steam bath with 50 cc. of kerosene. Filter the
+solution through a Gooch crucible properly prepared with asbestos,[28]
+wash the insoluble matter five times with 10-cc. portions of hot
+kerosene, and finally wash the residual kerosene out thoroughly with
+petroleum ether. Dry the crucible and contents to constant weight, as in
+the determination of moisture and volatile matter and report results as
+INSOLUBLE IMPURITIES.
+
+
+SOLUBLE MINERAL MATTER.
+
+Place the combined kerosene filtrate and kerosene washings from the
+insoluble impurities determination in a platinum dish. Place in this an
+ashless filter paper folded in the form of a cone, apex up. Light the
+apex of the cone, whereupon the bulk of the kerosene burns quietly. Ash
+the residue in a muffle, to constant weight, taking care that the
+decomposition of alkaline earth carbonates is complete, and report the
+result as SOLUBLE MINERAL MATTER.[29] When the percentage of soluble
+mineral matter amounts to more than 0.1 per cent, multiply the
+percentage by 10 and add this amount to the percentage of free fatty
+acids as determined.[30]
+
+
+FREE FATTY ACIDS.
+
+The ALCOHOL[31] used shall be approximately 95 per cent ethyl alcohol,
+freshly distilled from sodium hydroxide, which with phenolphthalein
+gives a definite and distinct end-point.
+
+DETERMINATION--Weigh 1 to 15 g. of the prepared sample into an
+Erlenmeyer flask, using the smaller quantity in the case of
+dark-colored, high acid fats. Add 50 to 100 cc. hot, neutral alcohol,
+and titrate with _N_/2, _N_/4 or _N_/10 sodium hydroxide depending on
+the fatty acid content, using phenolphthalein as indicator. Calculate to
+oleic acid, except that in the case of palm oil the results may also be
+expressed in terms of palmitic acid, clearly indicating the two methods
+of calculation in the report. In the case of coconut and palm kernel
+oils, calculate to and report in terms of lauric acid in addition to
+oleic acid, clearly indicating the two methods of calculation in the
+report. In the case of fats or greases containing more than 0.1 per cent
+of soluble mineral matter, add to the percentages of free fatty acids as
+determined 10 times the percentage of bases in the soluble mineral
+matter as determined.[30] This addition gives the equivalent of fatty
+acids combined with the soluble mineral matter.
+
+
+TITER.
+
+STANDARD THERMOMETER--The thermometer is graduated at zero and in tenth
+degrees from 10° C. to 65° C., with one auxiliary reservoir at the upper
+end and another between the zero mark and the 10° mark. The cavity in
+the capillary tube between the zero mark and the 10° mark is at least 1
+cm. below the 10° mark, the 10° mark is about 3 or 4 cm. above the bulb,
+the length of the thermometer being about 37 cm. over all. The
+thermometer has been annealed for 75 hrs. at 450° C. and the bulb is of
+Jena normal 16''' glass, or its equivalent, moderately thin, so that the
+thermometer will be quick-acting. The bulb is about 3 cm. long and 6 mm.
+in diameter. The stem of the thermometer is 6 mm. in diameter and made
+of the best thermometer tubing, with scale etched on the stem, the
+graduation is clear-cut and distinct, but quite fine. The thermometer
+must be certified by the U. S. Bureau of Standards.
+
+GLYCEROL CAUSTIC SOLUTION--Dissolve 250 g. potassium hydroxide in 1900
+cc. dynamite glycerin with the aid of heat.
+
+DETERMINATION--Heat 75 cc. of the glycerol-caustic solution to 150° C.
+and add 50 g. of the melted fat. Stir the mixture well and continue
+heating until the melt is homogeneous, at no time allowing the
+temperature to exceed 150° C. Allow to cool somewhat and carefully add
+50 cc. 30 per cent sulfuric acid. Now add hot water and heat until the
+fatty acids separate out perfectly clear. Draw off the acid water and
+wash the fatty acids with hot water until free from mineral acid, then
+filter and heat to 130° C. as rapidly as possible while stirring.
+Transfer the fatty acids, when cooled somewhat, to a 1-in. by 4-in.
+titer tube, placed in a 16-oz. salt-mouth bottle of clear glass, fitted
+with a cork that is perforated so as to hold the tube rigidly when in
+position. Suspend the titer thermometer so that it can be used as a
+stirrer and stir the fatty acids slowly (about 100 revolutions per
+minute) until the mercury remains stationary for 30 seconds. Allow the
+thermometer to hang quietly with the bulb in the center of the tube and
+report the highest point to which the mercury rises as the titer of the
+fatty acids. The titer should be made at about 20° C. for all fats
+having a titer above 30° C. and at 10° C. below the titer for all other
+fats. Any convenient means may be used for obtaining a temperature of
+10° below the titer of the various fats. The committee recommends first
+of all a chill room for this purpose; second, an artificially chilled
+small chamber with glass window; third, immersion of the salt-mouth
+bottle in water or other liquid of the desired temperature.
+
+
+UNSAPONIFIABLE MATTER.
+
+EXTRACTION CYLINDER--The cylinder shall be glass-stoppered, graduated at
+40 cc., 80 cc. and 130 cc., and of the following dimensions: diameter
+about 1-3/8 in., height about 12 in.
+
+PETROLEUM ETHER--Redistilled petroleum ether, boiling under 75° C.,
+shall be used. A blank must be made by evaporating 250 cc. with about
+0.25 g. of stearine or other hard fat (previously brought to constant
+weight by heating) and drying as in the actual determination. The blank
+must not exceed a few milligrams.
+
+DETERMINATION--Weigh 5 g. (±0.20 g.) of the prepared sample into a
+200-cc. Erlenmeyer flask, add 30 cc. of redistilled 95 per cent
+(approximately) ethyl alcohol and 5 cc. of 50 per cent aqueous potassium
+hydroxide, and boil the mixture for one hour under a reflux condenser.
+Transfer to the extraction cylinder and wash to the 40-cc. mark with
+redistilled 95 per cent ethyl alcohol. Complete the transfer, first with
+warm, then with cold water, till the total volume amounts to 80 cc. Cool
+the cylinder and contents to room temperature and add 50 cc. of
+petroleum ether. Shake _vigorously_ for one minute and allow to settle
+until both layers are clear, when the volume of the upper layer should
+be about 40 cc. Draw off the petroleum ether layer as closely as
+possible by means of a slender glass siphon into a separatory funnel of
+500 cc. capacity. Repeat extraction at least four more times, using 50
+cc. of petroleum ether each time. More extractions than five are
+necessary where the unsaponifiable matter runs high, say over 5 per
+cent, and also in some cases where it is lower than 5 per cent, but is
+extracted with difficulty. Wash the combined extracts in a separatory
+funnel three times with 25-cc. portions of 10 per cent alcohol, shaking
+vigorously each time. Transfer the petroleum ether extract to a
+wide-mouth tared flask or beaker, and evaporate the petroleum ether on a
+steam bath in an air current. Dry as in the method for MOISTURE AND
+VOLATILE MATTER. Any blank must be deducted from the weight before
+calculating unsaponifiable matter. Test the final residue for solubility
+in 50 cc. petroleum ether at room temperature. Filter and wash free from
+the insoluble residue, if any, evaporate and dry in the same manner as
+before. The Committee wishes to emphasize the necessity of thorough and
+vigorous shaking in order to secure accurate results. The two phases
+must be brought into the most intimate contact possible, otherwise low
+and disagreeing results may be obtained.
+
+
+IODINE NUMBER--WIJS METHOD.
+
+PREPARATION OF REAGENTS--_Wijs Iodine Solution_--Dissolve 13.0 g. of
+resublimed iodine in one liter of C. P. glacial acetic acid and pass in
+washed and dried chlorine gas until the original thiosulfate titration
+of the solution is not quite doubled. The solution is then preserved in
+amber glass-stoppered bottles, sealed with paraffin until ready for use.
+
+Mark the date on which the solution is prepared on the bottle or
+bottles and do not use Wijs solution which is more than 30 days old.
+
+There should be no more than a slight excess of iodine, and no excess of
+chlorine. When the solution is made from iodine and chlorine, this point
+can be ascertained by not quite doubling the titration.[32]
+
+The glacial acetic acid used for preparation of the Wijs solution should
+be of 99.0 to 99.5 per cent strength. In case of glacial acetic acids of
+somewhat lower strength, the Committee recommends freezing and
+centrifuging or draining as a means of purification.
+
+_N_/10 _Sodium Thiosulfate Solution_--Dissolve 24.8 g. of C. P. sodium
+thiosulfate in recently boiled distilled water and dilute with the same
+to one liter at the temperature at which the titrations are to be made.
+
+_Starch Paste_--Boil 1 g. of starch in 200 cc. of distilled water for 10
+min. and cool to room temperature.
+
+An improved starch solution may be prepared by autoclaving 2 g. of
+starch and 6 g. of boric acid dissolved in 200 cc. water at 15 lbs.
+pressure for 15 min. This solution has good keeping qualities.
+
+_Potassium Iodide Solution_--Dissolve 150 g. of potassium iodide in
+water and make up to one liter.
+
+_N_/10 _Potassium Bichromate_--Dissolve 4.903 g. of C. P. potassium
+bichromate in water and make the volume up to one liter at the
+temperature at which titrations are to be made.
+
+The Committee calls attention to the fact that occasionally potassium
+bichromate is found containing sodium bichromate, although this is of
+rare occurrence. If the analyst suspects that he is dealing with an
+impure potassium bichromate, the purity can be ascertained by titration
+against re-sublimed iodine. However, this is unnecessary in the great
+majority of cases.
+
+_Standardization of the Sodium Thiosulfate Solution_--Place 40 cc. of
+the potassium bichromate solution, to which has been added 10 cc. of the
+solution of potassium iodide, in a glass-stoppered flask. Add to this 5
+cc. of strong hydro-chloric acid. Dilute with 100 cc. of water, and
+allow the _N_/10 sodium thiosulfate to flow slowly into the flask until
+the yellow color of the liquid has almost disappeared. Add a few drops
+of the starch paste, and with constant shaking continue to add the
+_N_/10 sodium thiosulfate solution until the blue color just disappears.
+
+DETERMINATION--Weigh accurately from 0.10 to 0.50 g. (depending on the
+iodine number) of the melted and filtered sample into a clean, dry,
+16-oz. glass-stoppered bottle containing 15-20 cc. of carbon
+tetrachloride or chloroform. Add 25 cc. of iodine solution from a
+pipette, allowing to drain for a definite time. The excess of iodine
+should be from 50 per cent to 60 per cent of the amount added, that is,
+from 100 per cent to 150 per cent of the amount absorbed. Moisten the
+stopper with a 15 per cent potassium iodide solution to prevent loss of
+iodine or chlorine but guard against an amount sufficient to run down
+inside the bottle. Let the bottle stand in a dark place for 1/2 hr. at
+a uniform temperature. At the end of that time add 20 cc. of 15 per cent
+potassium iodide solution and 100 cc. of distilled water. Titrate the
+iodine with _N_/10 sodium thiosulfate solution which is added gradually,
+with constant shaking, until the yellow color of the solution has almost
+disappeared. Add a few drops of starch paste and continue titration
+until the blue color has entirely disappeared. Toward the end of the
+reaction stopper the bottle and shake violently so that any iodine
+remaining in solution in the tetrachloride or chloroform may be taken up
+by the potassium iodide solution. Conduct two determinations on blanks
+which must be run in the same manner as the sample except that no fat is
+used in the blanks. Slight variations in temperature quite appreciably
+affect the titer of the iodine solution, as acetic acid has a high
+coefficient of expansion. It is, therefore, essential that the blanks
+and determinations on the sample be made at the same time. The number of
+cc. of standard thiosulfate solution required by the blank, less the
+amount used in the determination, gives the thiosulfate equivalent of
+the iodine absorbed by the amount of sample used in the determination.
+Calculate to centigrams of iodine absorbed by 1 g. of sample (= per cent
+iodine absorbed).
+
+DETERMINATION, TUNG OIL--Tung oil shows an erratic behavior with most
+iodine reagents and this is particularly noticeable in the case of the
+Hanus reagent which is entirely unsuitable for determining the iodine
+number of this oil since extremely high and irregular results are
+obtained. The Hübl solution shows a progressive absorption up to 24 hrs.
+and probably for a longer time but the period required is entirely too
+long for a chemical determination. The Wijs solution gives good results
+if the following precautions are observed:
+
+Weigh out 0.15 ± 0.05 g., use an excess of 55 ± 3 per cent Wijs
+solution. Conduct the absorption at a temperature of 20-25° C. for 1 hr.
+In other respects follow the instructions detailed above.
+
+
+SAPONIFICATION NUMBER (KOETTSTORFER NUMBER).
+
+PREPARATION OF REAGENTS. _N/2 Hydrochloric Acid_--Carefully
+standardized.
+
+_Alcoholic Potassium Hydroxide Solution_--Dissolve 40 g. of pure
+potassium hydroxide in one liter of 95 per cent redistilled alcohol (by
+volume). The alcohol should be redistilled from potassium hydroxide over
+which it has been standing for some time, or with which it has been
+boiled for some time, using a reflux condenser. The solution must be
+clear and the potassium hydroxide free from carbonates.
+
+DETERMINATION--Weigh accurate about 5 g. of the filtered sample into a
+250 to 300 cc. Erlenmeyer flask. Pipette 50 cc. of the alcoholic
+potassium hydroxide solution into the flask, allowing the pipette to
+drain for a definite time. Connect the flask with an air condenser and
+boil until the fat is completely saponified (about 30 minutes). Cool and
+titrate with the _N_/2 hydrochloric acid, using phenolphthalein as an
+indicator. Calculate the Koettstorfer number (mg. of potassium hydroxide
+required to saponify 1 g. of fat). Conduct 2 or 3 blank determinations,
+using the same pipette and draining for the same length of time as
+above.
+
+
+MELTING POINT.
+
+APPARATUS--_Capillary tubes_ made from 5 mm. inside diameter thin-walled
+glass tubing drawn out to 1 mm. inside diameter. Length of capillary
+part of tubes to be about 5 cm. Length of tube over all 8 cm.
+
+_Standard thermometer_ graduated in tenths of a degree.
+
+_600 cc. beaker._
+
+DETERMINATION--The sample should be clear when melted and entirely free
+from moisture, or incorrect results will be obtained.
+
+Melt and thoroughly mix the sample. Dip three of the capillary tubes
+above described in the oil so that the fat in the tube stands about 1
+cm. in height. Now fuse the capillary end carefully by means of a small
+blast flame and allow to cool. These tubes are placed in a refrigerator
+over night at a temperature of from 40 to 50° F. They are then fastened
+by means of a rubber band or other suitable means to the bulb of a
+thermometer graduated in tenths of a degree. The thermometer is
+suspended in a beaker of water (which is agitated by air or other
+suitable means) so that the bottom of the bulb of the thermometer is
+immersed to a depth of about 3 cm. The temperature of the water is
+increased gradually at the rate of about 1° per minute.
+
+The point at which the sample becomes opalescent is first noted and the
+heating continued until the contents of the tube becomes uniformly
+transparent. The latter temperature is reported as the melting point.
+
+Before finally melting to a perfectly clear fluid, the sample becomes
+opalescent and usually appears clear at the top, bottom, and sides
+before becoming clear at the center. The heating is continued until the
+contents of the tube become uniformly clear and transparent. This
+temperature is reported as the melting point.[33] It is usually only a
+fraction of a degree above the opalescent point noted. The thermometer
+should be read to the nearest 1/2° C., and in addition this temperature
+may be reported to the nearest degree Fahrenheit if desired.
+
+
+CLOUD TEST.
+
+PRECAUTIONS--(1) The oil must be perfectly dry, because the presence of
+moisture will produce a turbidity before the clouding point is reached.
+
+(2) The oil must be heated to 150° C. over a free flame, immediately
+before making the test.
+
+(3) There must not be too much discrepancy between the temperature of
+the bath and the clouding point of the oil. An oil that will cloud at
+the temperature of hydrant water should be tested in a bath of that
+temperature. An oil that will cloud in a mixture of ice and water should
+be tested in such a bath. An oil that will not cloud in a bath of ice
+and water must be tested in a bath of salt, ice, and water.
+
+DETERMINATION--The oil is heated in a porcelain casserole over a free
+flame to 150° C., stirring with the thermometer. As soon as it can be
+done with safety, the oil is transferred to a 4 oz. oil bottle, which
+must be perfectly dry. One and one-half ounces of the oil are sufficient
+for the test. A dry centigrade thermometer is placed in the oil, and the
+bottle is then cooled by immersion in a suitable bath. The oil is
+constantly stirred with the thermometer, taking care not to remove the
+thermometer from the oil at any time during the test, so as to avoid
+stirring air bubbles into the oil. The bottle is frequently removed from
+the bath for a few moments. The oil must not be allowed to chill on the
+sides and bottom of the bottle. This is effected by constant and
+vigorous stirring with the thermometer. As soon as the first permanent
+cloud shows in the body of the oil, the temperature at which this cloud
+occurs is noted.
+
+With care, results concordant to within 1/2° C. can be obtained by this
+method. A Fahrenheit thermometer is sometimes used because it has become
+customary to report results in degrees Fahrenheit.
+
+The oil must be tested within a short time after heating to 150° C. and
+a re-test must always be preceded by reheating to that temperature. The
+cloud point should be approached as quickly as possible, yet not so
+fast that the oil is frozen on the sides or bottom of the bottle before
+the cloud test is reached.
+
+
+Notes on the Above Methods.
+
+
+SAMPLING.
+
+The standard size of sample adopted by the committee is at least 3 lbs.
+in weight. The committee realizes that this amount is larger than any
+samples usually furnished even when representing shipments of from
+20,000 to 60,000 lbs. but it believes that the requirement of a larger
+sample is desirable and will work toward uniform and more concordant
+results in analysis. It will probably continue to be the custom of the
+trade to submit smaller buyers' samples than required by the committee,
+but these are to be considered only as samples for inspection and not
+for analysis. The standard analytical sample must consist of 3 lbs. or
+more.
+
+The reasons for keeping samples in a dark, cool place are obvious. This
+is to prevent any increase in rancidity and any undue increase in free
+fatty acids. In the case of many fats the committee has found in its
+co-operative analytical work that free acid tends to increase very
+rapidly. This tendency is minimized by low temperatures.
+
+
+MOISTURE AND VOLATILE MATTER.
+
+After careful consideration the committee has decided that moisture is
+best determined in a vacuum oven of the design which accompanies the
+above report. Numerous results on check samples have confirmed the
+committee's conclusions. The oven recommended by the committee is
+constructed on the basis of well-known principles and it is hoped that
+this type will be adopted generally by chemists who are called upon to
+analyze fats and oils. The experiments of the committee indicate that it
+is a most difficult matter to design a vacuum oven which will produce
+uniform temperatures throughout; and one of the principal ideas in the
+design adopted is uniformity of temperature over the entire single
+shelf. This idea has not quite been realized in practice but,
+nevertheless, the present design approaches much closer to the ideal
+than other vacuum ovens commonly used. In the drawing the essential
+dimensions are those between the heating units and the shelf and the
+length and breadth of the outer casting. The standard Fat Analysis
+Committee Oven (F. A. C. Oven) can be furnished by Messrs. E. H. Sargent
+& Company, 125 West Lake street, Chicago.
+
+The committee realizes that for routine work a quicker method is
+desirable and has added one such method and has also stated the
+conditions under which comparable results can be obtained by means of
+the ordinary well-ventilated air oven held at 105 to 110° C. However, in
+accordance with a fundamental principle adopted by the committee at its
+first meeting, only one standard method is adopted and declared official
+for each determination.
+
+The committee realizes that in the case of all methods for determining
+moisture by means of loss on heating there may be a loss due to volatile
+matter (especially fatty acids) other than water. The title of the
+determination MOISTURE AND VOLATILE MATTER indicates this idea, but any
+considerable error from this source may occur only in the case of high
+acid fats and oils and particularly those containing lower fatty acids
+such as coconut and palm kernel oil. In the case of extracted greases
+which have not been properly purified, some of the solvent may also be
+included in the moisture and volatile matter determination, but inasmuch
+as the solvent, usually a petroleum product, can only be considered as
+foreign matter, for commercial purposes, it is entirely proper to
+include it with the moisture.
+
+The committee has also considered the various distillation methods for
+the determination of moisture in fats and oils, but since according to
+the fundamental principles which it was endeavoring to follow it could
+only standardize one method, it was decided that the most desirable one
+on the whole was the vacuum-oven method as given. There are cases
+wherein a chemist may find it desirable to check a moisture
+determination or investigate the moisture content of a fat or oil
+further by means of one of the distillation methods.
+
+However, in co-operative work the distillation method in various types
+of apparatus has not yielded satisfactory results. The difficulties
+appear to be connected with a proper choice of solvent and particularly
+with the tendency of drops of water to adhere to various parts of the
+glass apparatus instead of passing on to the measuring device. When
+working on coconut oil containing a high percentage of free fatty acids,
+concordant results could not be obtained by the various members of the
+committee when working with identical samples, solvents and apparatus.
+
+On the other hand, the committee found by individual work, co-operative
+work and collaborative work by several members of the committee in one
+laboratory, that the old, well-known direct heating method (which the
+committee has designated the hot plate method) yielded very satisfactory
+results on all sorts of fats and oils including emulsions such as butter
+and oleomargarine and even on coconut oil samples containing 15 to 20
+per cent free fatty acids and 5 to 6 per cent of moisture.
+Unfortunately, this method depends altogether on the operator's skill
+and while the method may be taught to any person whether a chemist or
+not so that he can obtain excellent results with it, it is difficult to
+give a sufficiently, complete description of it so that any chemist
+anywhere after reading the description could follow it successfully. The
+method is undoubtedly worthy of much confidence in careful hands. It is
+quick, accurate and reliable. It is probably the best single method for
+the determination of moisture in all sorts of samples for routine
+laboratory work. On account of this fact the committee desires to
+announce its willingness to instruct any person in the proper use of the
+method who desires to become acquainted with it and who will visit any
+committee member's laboratory.
+
+
+INSOLUBLE IMPURITIES.
+
+This determination, the title for which was adopted after careful
+consideration, determines the impurities which have generally been known
+as dirt, suspended matter, suspended solids, foreign solids, foreign
+matter, etc., in the past. The first solvent recommended by the
+committee is hot kerosene to be followed by petroleum ether kept at
+ordinary room temperature. Petroleum ether, cold or only slightly warm,
+is not a good fat and metallic soap solvent, whereas hot kerosene
+dissolves these substances readily, and for this reason the committee
+has recommended the double solvent method so as to exclude metallic
+soaps which are determined below as soluble mineral matter.
+
+
+SOLUBLE MINERAL MATTER.
+
+Soluble mineral matter represents mineral matter combined with fatty
+acids in the form of soaps in solution in the fat or oil. Formerly, this
+mineral matter was often determined in combination by weighing the
+separated metallic soap or by weighing it in conjunction with the
+insoluble impurities. Since the soaps present consist mostly of lime
+soap, it has been customary to calculate the lime present therein by
+taking 0.1 the weight of the total metallic soaps. The standard method
+as given above is direct and involves no calculation. The routine method
+given in the note has been placed among the methods for the reason that
+it is used in some laboratories, but has not been adopted as a standard
+method in view of the fact that the committee has made it a rule to
+adopt only one standard method. It should be pointed out, however, that
+the method cannot be considered accurate for the reason that insoluble
+impurities may vary from sample to sample to a considerable extent and
+the error due to the presence of large particles of insoluble impurities
+is thus transferred to the soluble mineral matter. The committee has
+found one type of grease (naphtha bone grease) which shows most unusual
+characteristics. The type sample contains 4.3 per cent soluble mineral
+matter by the committee method which would be equivalent to 43.0 per
+cent free fatty acid. The kerosene and gasoline filtrate was
+particularly clear, nevertheless the ash was found to contain 36.43 per
+cent P_{2}O_{5} equivalent to 79.60 per cent of Ca_{3}(PO_{4})_{2} and
+9.63 per cent of Fe_{2}O_{3}. The method, therefore, determines the
+soluble mineral matter in this case satisfactorily but the factor 10 is
+not applicable for calculating the fatty acids combined therewith. It is
+necessary, therefore, in order to determine the fatty acids combined
+with soluble mineral matter in the original sample to determine the
+actual bases in the soluble mineral matter as obtained by ashing the
+kerosene and gasoline filtrate. To the bases so determined the factor 10
+can then be applied.
+
+
+FREE FATTY ACID.
+
+The fatty acid method adopted is sufficiently accurate for commercial
+purposes. In many routine laboratories the fat or oil is measured and
+not weighed, but the committee recommends weighing the sample in all
+cases. For scientific purposes the result is often expressed as "acid
+number," meaning the number of milligrams of KOH required to neutralize
+the free acids in one gram of fat, but the commercial practice has been,
+and is, to express the fatty acids as oleic acid or in the case of palm
+oil, as palmitic acid, in some instances. The committee sees no
+objection to the continuation of this custom so long as the analytical
+report clearly indicates how the free acid is expressed. For a more
+exact expression of the free acid in a given fat, the committee
+recommends that the ratio of acid number to saponification number be
+used. This method of expressing results is subject to error when
+unsaponifiable fatty matter is present, since the result expresses the
+ratio of free fatty acid to total saponifiable fatty matter present.
+
+
+TITER.
+
+At the present time the prices of glycerol and caustic potash are
+abnormally high, but the committee has considered that the methods
+adopted are for normal times and normal prices. For routine work during
+the period of high prices the following method may be used for preparing
+the fatty acids and is recommended by the committee:
+
+Fifty grams of fat are saponified with 60 cc. of a solution of 2 parts
+of methyl alcohol to 1 of 50 per cent NaOH. The soap is dried,
+pulverized and dissolved in 1000 cc. of water in a porcelain dish and
+then decomposed with 25 cc. of 75 per cent sulphuric acid. The fatty
+acids are boiled until clear oil is formed and then collected and
+settled in a 150-cc. beaker and filtered into a 50-cc. beaker. They are
+then heated to 130° C. as rapidly as possible with stirring, and
+transferred, after they have cooled somewhat, to the usual 1-in. by
+4-in. titer tube.
+
+The method of taking the titer, including handling the thermometer, to
+be followed is the same as that described in the standard method. Even
+at present high prices many laboratories are using the glycerol-caustic
+potash method for preparing the fatty acids, figuring that the saving of
+time more than compensates for the extra cost of the reagents. Caustic
+soda cannot be substituted for caustic potash in the glycerol method.
+
+UNSAPONIFIABLE MATTER.
+
+The committee has considered unsaponifiable matter to include those
+substances frequently found dissolved in fats and oils which are not
+saponified by the caustic alkalies and which at the same time are
+soluble in the ordinary fat solvents. The term includes such substances
+as the higher alcohols, such as cholesterol which is found in animal
+fats, phytosterol found in some vegetable fats, paraffin and petroleum
+oils, etc. UNSAPONIFIABLE MATTER should not be confused in the lay mind
+with INSOLUBLE IMPURITIES OR SOLUBLE MINERAL MATTER.
+
+The method adopted by the committee has been selected only after the
+most careful consideration of other methods, such as the dry extraction
+method and the wet method making use of the separatory funnel. At first
+consideration the dry extraction process would seem to offer the best
+basis for an unsaponifiable matter method, but in practice it has been
+found absolutely impossible for different analysts to obtain agreeing
+results when using any of the dry extraction methods proposed.
+Therefore, this method had to be abandoned after numerous trials,
+although several members of the committee strongly favored it in the
+beginning.
+
+IODINE NUMBER--The iodine number adopted by the committee is that
+determined by the well-known Wijs method. This method was adopted after
+careful comparison with the Hanus and Hübl methods. The Hübl method was
+eliminated from consideration almost at the beginning of the committee's
+work for the reason that the time required for complete absorption of
+the iodine is unnecessarily long and, in fact, even after absorption has
+gone on over night, it is apparently not complete. In the case of the
+Hanus and Wijs methods complete absorption takes place in from 15
+minutes to an hour, depending on conditions. Formerly, many chemists
+thought the Hanus solution rather easier to prepare than the Wijs
+solution, but the experience of the committee was that the Wijs solution
+was no more difficult to prepare than the Hanus. Furthermore, absorption
+of iodine from the Wijs solution appeared to take place with greater
+promptness and certainty than from the Hanus and was complete in a
+shorter time. Results by the Wijs method were also in better agreement
+in the case of oils showing high iodine absorption than with the Hanus
+solution and showed a slightly higher iodine absorption for the same
+length of time. However, the difference was not great. The committee
+investigated the question of substitution since it has been suggested
+that in case of the Wijs solution substitution of iodine in the organic
+molecule might occur, and found no evidence of this in the time required
+for the determination, namely, 1/2 hr., or even for a somewhat longer
+period. One member of the committee felt that it was not desirable to
+introduce the Wijs method into these standard methods since the Hanus
+method was already standardized by the Association of Official
+Agricultural Chemists, but the committee felt that it must follow the
+principle established at the commencement of its work, namely, that of
+adopting the method which appeared to be the best from all standpoints,
+taking into consideration accuracy, convenience, simplicity, time,
+expense, etc., without allowing precedent to have the deciding vote.
+
+IODINE NUMBER, TUNG OIL--The committee has made an extensive study of
+the application of the Wijs method to the determination of iodine value
+in the case of tung oil with the result that it recommends the method
+for this oil but has thought it desirable to limit the conditions under
+which the determination is conducted rather narrowly, although
+reasonably good results are obtained by the committee method without
+making use of the special limitations.
+
+The co-operative work of the committee and the special investigations
+conducted by individual members bring out the following points:
+
+_Influence of Temperature_--From 16° C. to 30° C. there is a moderate
+increase in the absorption, but above 30° the increase is rather rapid
+so that it was thought best to limit the temperature in the case of tung
+oil to 20° to 25° C.
+
+_Influence of Time_--The absorption increases with the time but
+apparently complete absorption, so far as unsaturated bonds are
+concerned, occurs well within one hour's time. Consequently, one hour
+was set as the practical limit.
+
+_Influence of Excess_--The excess of iodine solution also tends to
+increase the iodine number, hence the Committee thought it necessary to
+limit the excess rather rigidly to 55 ± 3 per cent, although with
+greater latitude results were reasonably good.
+
+_Influence of Age of Solution_--Old solutions tend to give low results
+although up to 2 mo. no great differences were observed. Nevertheless,
+it was thought best to limit the age of the solution to 30 days--long
+enough for all practical purposes.
+
+_Amount of Sample_--As a practical amount of sample to be weighed out
+the Committee decided on 0.15 g. with a tolerance of 0.05 g. in either
+direction according to preference. In other words, the amount of sample
+to be taken for the determination to be from 0.1 to 0.2 g. in the
+discretion of the analyst.
+
+The Committee's study of the Hübl method which has been adopted by the
+Society for Testing Materials in the case of tung oil indicates that
+this method when applied to tung oil is subject to the same influences
+as the Wijs method and it has the additional very serious disadvantage
+of requiring a long period of time for absorption which cannot be
+considered reasonable for a modern analytical method. When using the
+Hübl solution, the absorption is not complete in the case of tung oil
+at 3, 7, 18 or even 24 hrs.
+
+The Hanus method in the case of tung oil gives very high and erratic
+results, as high as 180 to 240 in ordinary cases for an oil whose true
+iodine number is about 165.
+
+
+MELTING POINT.
+
+A melting point is the temperature at which a solid substance assumes
+the liquid condition. If the solid is a pure substance in the
+crystalline condition the melting point is sharp and well defined for
+any given pressure. With increased pressure the melting point is lowered
+or raised, depending on whether the substance contracts or expands in
+melting. The lowering or raising of the melting point with pressure is
+very slight and ordinarily is not taken into consideration.
+Melting-point determinations are commonly carried out under ordinary
+atmospheric pressures without correction. The general effect of soluble
+impurities is to lower the melting point, and this holds true whether
+the impurity has a higher or lower melting point than the pure substance
+(solvent). Thus if a small amount of stearic acid be added to liquid
+palmitic acid and the solution frozen, the melting point of this solid
+will be lower than that of palmitic acid. Likewise the melting point of
+stearic acid is lowered by the addition of a small amount of palmitic
+acid. A eutectic mixture results when two components solidify
+simultaneously at a definite temperature. Such a mixture has a constant
+melting point and because of this and also because both solid and liquid
+phases have the same composition, eutectic mixtures were formerly looked
+upon as compounds. The phenomenon of double melting points has been
+observed in the case of a number of glycerides. Such a glyceride when
+placed in the usual capillary tube and subjected to increasing
+temperature quickly resolidifies only to melt again and remain melted
+at a still higher temperature. This phenomenon has not yet been
+sufficiently investigated to afford a satisfactory explanation.
+
+Non-crystalline substances such as glass, sealing wax and various other
+waxes and wax mixtures, and most colloidal substances do not exhibit a
+sharp melting point, but under the application of heat first soften very
+gradually and at a considerably higher temperature melt sufficiently to
+flow. This phenomenon of melting through a long range of temperature may
+be due to the amorphous nature of the substance or to the fact that it
+consists of a very large number of components of many different melting
+points.
+
+The fats and oils of natural origin, that is, the animal and vegetable
+fats and oils, consist of mixtures of glycerides and, generally
+speaking, of a considerable number of such components. These components
+are crystalline and when separated in the pure state have definite
+melting points, although some exhibit the phenomenon of double melting
+point. For the most part the naturally occurring glycerides are mixed
+glycerides. In the natural fats and oils there are present also certain
+higher alcohols, of which cholesterol is characteristic of the animal
+fats and oils and phytosterol of many of the vegetable fats and oils. In
+addition to the crystalline glycerides and the higher alcohols present
+in neutral fats, there are in fats of lower grade, fatty acids, which
+are crystalline, and also various non-crystalline impurities of an
+unsaponifiable nature, and the presence of these impurities tends to
+lower the melting point. They also tend to induce undercooling and when
+the liquid fat or oil is being chilled for purposes of solidification or
+in determination of titer.
+
+The presence of water, especially when this is thoroughly mixed or
+emulsified with a fat or oil, also influences the melting point to a
+marked extent, causing the mixture to melt through a longer range of
+temperatures than would be the case if the water were absent. This is
+particularly true of emulsified fats and oils, such as butter and
+oleomargarine, both of which contain, besides water, the solids
+naturally present in milk or cream and including casein, milk sugar, and
+salts. The melting-point method recommended by the Committee is not
+applicable to such emulsions or other watery mixtures and the Committee
+has found it impossible to devise an accurate method for making
+softening-point or melting-point determinations on products of this
+nature. Not only the amount of water present but also the fineness of
+its particles, that is, its state of subdivision and distribution, in a
+fat or oil influences the softening point or melting point and causes it
+to vary widely in different samples.
+
+As a consequence of the foregoing facts, natural fats and oils do not
+exhibit a definite melting point, composed as they are of mixtures of
+various crystalline glycerides, higher alcohols, fatty acids, and
+non-crystalline substances. Therefore, the term melting point when
+applied to them requires further definition. They exhibit first a lower
+melting point (the melting point of the lowest melting component) or
+what might be called the softening point and following this the fat
+softens through a shorter or longer range of temperature to the final
+melting point at which temperature the fat is entirely liquid. This is
+the melting point determined by the Committee's melting-point method.
+The range between the softening point and the final melting point varies
+greatly with the different fats and oils depending on their chemical
+components, the water associated with them, emulsification, etc. In the
+case of coconut oil the range between softening point and final melting
+point is rather short; in the case of butter, long. Various methods have
+been devised to determine the so-called melting point of fats and oils.
+Most of these methods, however, determine, not the melting point, but
+the softening point or the flow point of the fat and the great
+difficulty has been in the past to devise a method which would determine
+even this point with reasonable accuracy and so that results could be
+easily duplicated. It has been the aim of the Committee to devise a
+simple method for the determination of the melting point of fats and
+oils, but it should be understood that the term melting point in the
+scientific sense is not applicable to natural fats and oils.
+
+FOOTNOTES:
+
+[22] Approved by the Supervisory Committee on Standard Methods of
+Analysis of the American Chemical Society.
+
+[23] Live steam must not be turned into tank cars or coils before
+samples are drawn, since there is no certain way of telling when coils
+are free from leaks.
+
+[24] If there is water present under the solid material this must be
+noted and estimated separately.
+
+[25] Boiling point of water at reduced pressures.
+
+ Pressure    Boiling Point   Boiling Point   Boiling Point
+  Mm. Hg.      to 1° C.        +15° C.           +20° C.
+   100           52° C.         67° C.            72° C.
+    90           50             65                70
+    80           47             62                67
+    70           45             60                65
+    60           42             57                62
+    50           38             53                58
+    40           34             49                54
+
+[26] Results comparable to those of the Standard Method may be obtained
+on most fats and oils by drying 5-g. portions of the sample, prepared
+and weighed as above, to constant weight in a well-constructed and
+well-ventilated air oven held uniformly at a temperature of 105° to 110°
+C. The thermometer bulb should be close to the sample. The definition of
+constant weight is the same as for the Standard Method.
+
+[27] The following method is suggested by the Committee for routine
+control work: Weigh out 5- to 25-g. portions of prepared sample into a
+glass or aluminum (_Caution_: Aluminum soap may be formed) beaker or
+casserole and heat on a heavy asbestos board over burner or hot plate,
+taking care that the temperature of the sample does not go above 130° C.
+at any time. During the heating rotate the vessel gently on the board by
+hand to avoid sputtering or too rapid evolution of moisture. The proper
+length of time of heating is judged by absence of rising bubbles of
+steam, by the absence of foam or by other signs known to the operator.
+Avoid overheating of sample as indicated by smoking or darkening. Cool
+in desiccator and weigh.
+
+By co-operative work in several laboratories, the Committee has
+demonstrated that this method can be used and satisfactory results
+obtained on coconut oil even when a considerable percentage of free
+fatty acids is present, and the method is recommended for this purpose.
+Unfortunately on account of the very great personal factor involved, the
+Committee cannot establish this method as a preferred method.
+Nevertheless, after an operator has learned the technique of the method,
+it gives perfectly satisfactory results for ordinary oils and fats,
+butter, oleomargarine and coconut oil, and deserves more recognition
+than it has heretofore received.
+
+[28] For routine control work, filter paper is sometimes more convenient
+than the prepared Gooch crucible, but must be very carefully washed,
+especially around the rim, to remove the last traces of fat.
+
+[29] For routine work, an ash may be run on the original fat, and the
+soluble mineral matter obtained by deducting the ash on the insoluble
+impurities from this. In this case the Gooch crucible should be prepared
+with an ignited asbestos mat so that the impurities may be ashed
+directly after being weighed. In all cases ignition should be to
+constant weight so as to insure complete decomposition of carbonates.
+
+[30] See note on Soluble Mineral Matter following these methods. When
+the ash contains phosphates the factor 10 cannot be applied, but the
+bases consisting of calcium oxide, etc., must be determined, and the
+factor 10 applied to them.
+
+[31] For routine work methyl or denatured ethyl alcohol of approximately
+95 per cent strength may be used. With these reagents the end-point is
+not sharp.
+
+[32] P. C. McIlhiney, _J. Am. Chem. Soc._, 29 (1917), 1222, gives the
+following details for the preparation of the iodine monochloride
+solution:
+
+The preparation of the iodine monochloride solution presents no great
+difficulty, but it must be done with care and accuracy in order to
+obtain satisfactory results. There must be in the solution no sensible
+excess either of iodine or more particularly of chlorine, over that
+required to form the monochloride. This condition is most satisfactorily
+attained by dissolving in the whole of the acetic acid to be used the
+requisite quantity of iodine, using a gentle heat to assist the
+solution, if it is found necessary, setting aside a small portion of
+this solution, while pure and dry chlorine is passed into the remainder
+until the halogen content of the whole solution is doubled. Ordinarily
+it will be found that by passing the chlorine into the main part of the
+solution until the characteristic color of free iodine has just been
+discharged there will be a slight excess of chlorine which is corrected
+by the addition of the requisite amount of the unchlorinated portion
+until all free chlorine has been destroyed. A slight excess of iodine
+does little or no harm, but excess of chlorine must be avoided.
+
+[33] The melting point of oils may be determined in general according to
+the above procedure, taking into consideration the lower temperature
+required.
+
+
+
+
+PLANT AND MACHINERY
+
+Illustrations of machinery and layouts of the plant of a modern
+soap-making establishment.
+
+[Illustration: HOIST, LYE TANK, ETC.]
+
+[Illustration: MELTING-OUT TROUGH]
+
+[Illustration: LAUNDRY SOAP PLANT]
+
+[Illustration: DRYING RACK]
+
+[Illustration: SOAP KETTLE]
+
+[Illustration: REMELTER]
+
+[Illustration: CRUTCHER (Cross Section)]
+
+[Illustration: HORIZONTAL CRUTCHER]
+
+[Illustration: CRUTCHER]
+
+[Illustration: WRAPPING MACHINE (LAUNDRY SOAP)]
+
+[Illustration: SLABBER]
+
+[Illustration: CUTTING TABLE]
+
+[Illustration: AUTOMATIC POWER CUTTING TABLE]
+
+[Illustration: AUTOMATIC PRESS (LAUNDRY)]
+
+[Illustration: CUTTING TABLE (HAND)]
+
+[Illustration: CARTON WRAPPING MACHINE]
+
+[Illustration: DRYING RACKS]
+
+[Illustration: SOAP POWDER BOX]
+
+[Illustration: SCOURING SOAP PRESS]
+
+[Illustration: FRAME]
+
+[Illustration: SOAP POWDER EQUIPMENT]
+
+[Illustration: FLUFFY SOAP POWDER EQUIPMENT]
+
+[Illustration: SOAP POWDER MIXER]
+
+[Illustration: SOAP POWDER MILL]
+
+[Illustration: TOILET SOAP EQUIPMENT]
+
+[Illustration: TOILET SOAP DRYER]
+
+[Illustration: MILLING BOX]
+
+[Illustration: AMALGAMATOR]
+
+[Illustration: TOILET SOAP MILL]
+
+[Illustration: TOILET SOAP MILL]
+
+[Illustration: CHIPPER]
+
+[Illustration: PLODDER]
+
+[Illustration: HORIZONTAL CHIPPER]
+
+[Illustration: AMALGAMATOR (IMPROVED)]
+
+[Illustration: PRESS (LETTERING ON 4 SIDES OF CAKE)]
+
+[Illustration: Press (Foot)]
+
+[Illustration: Press (Foot)]
+
+[Illustration: PLODDER]
+
+[Illustration: AUTOMATIC PRESS (TOILET)]
+
+[Illustration: MULTIPLE CAKE CUTTER]
+
+[Illustration: CAKE CUTTER]
+
+[Illustration: CHIPPER]
+
+[Illustration: GLYCERINE DISTILLING PLANT]
+
+[Illustration: CRUDE GLYCERINE PLANT]
+
+[Illustration: H-A FATTY ACID DISTILLING PLANT]
+
+
+
+
+Appendix
+
+Tables marked * are taken from the German Year Book for Soap Industry.
+
+
+(U. S. BUREAU OF STANDARDS)
+
+THE METRIC SYSTEM.
+
+The fundamental unit of the metric system is the meter (the unit of
+length). From this the units of mass (gram) and capacity (liter) are
+derived. All other units are the decimal sub-divisions or multiples of
+these. These three units are simply related, so that for all practical
+purposes the volume of one kilogram of water (one liter) is equal to one
+cubic decimeter.
+
+
+============================================================
+                                        |
+Prefixes.       Meaning.                |     Units.
+________________________________________|___________________
+                                        |
+Milli- = one thousandth 1-1000     .001 |
+Centi- = one hundredth 1-100       .01  | Meter for length.
+Deci- = one tenth 1-10             .1   |
+Unit = one                        1.    | Gram for mass.
+Deka- = ten 10-1                 10.    |
+Hecto- = one hundred 100-1      100.    | Liter for capacity.
+Kilo- = one thousand 1000-1    1000.    |
+============================================================
+
+The metric terms are formed by combining the words "Meter," "Gram" and
+"Liter" with the six numerical prefixes.
+
+
+LENGTH
+
+10 milli-meters mm = 1 centi-meter                  c m
+
+10 centi-meters    = 1 deci-meter                   d m
+
+10 deci-meters     = 1 meter (about 40 inches)        m
+
+10 meters          = 1 deka-meter                 d k m
+
+10 deka-meters     = 1 hecto-meter                  h m
+
+10 hecto-meters    = 1 kilo-meter (about 5/8 mile)  k m
+
+
+MASS.
+
+10 milli-grams. m g = 1 centi-gram                   c g
+10 centi-grams      = 1 deci-gram                    d g
+10 deci-grams       = 1 gram (about 15 grains)         g
+10 grams            = 1 deka-gram                  d k g
+10 Deka-grams       = 1 hecto-gram                   h g
+10 hecto-grams      = 1 kilo-gram (about 2 pounds)   k g
+
+
+CAPACITY.
+
+10 milli-liters. m l = 1 centi-liter                    c l
+10 centi-liters      = 1 deci-liter                     d l
+10 deci-liters       = 1 liter (about 1 quart)            l
+10 liters            = 1 deka-liter                   d k l
+10 deka-liters       = 1 hecto-liter (about a barrel)   h l
+10 hecto-liters      = 1 kilo-liter                     k l
+
+The square and cubic units are the squares and cubes of the linear
+units.
+
+The ordinary unit of land area is the Hectare (about 2-1/2 acres).
+
+
+U.S. BUREAU OF STANDARDS TABLE OF METRIC EQUIVALENTS
+
+
+Meter = 39.37 inches.
+
+Legal Equivalent Adopted by Act of Congress July 28, 1866.
+
+
+LENGTH.
+
+Centimeter              = 0.3937 inch
+Meter                   = 3.28 feet
+Meter                   = 1.094 yards
+Kilometer               = 0.621 statute mile
+Kilometer               = 0.5396 nautical mile
+Inch                    = 2.540 centimeters
+Foot                    = 0.305 meter
+Yard                    = 0.914 meter
+Statute mile            = 1.61 kilometers
+Nautical mile           = 1.853 kilometers
+
+
+AREA.
+
+Sq. centimeter          = 0.155 sq. inch
+Sq. meter               = 10.76 sq. feet
+Sq. meter               = 1.196 sq. yards
+Hectare                 = 2.47 acres
+Sq. kilometer           = 0.386 sq. mile
+Sq. inch                = 6.45 sq. centimeters
+Sq. foot                = 0.0929 sq. meter
+Sq. yard                = 0.836 sq. meter
+Acre                    = 0.405 hectare
+Sq. mile                = 2.59 sq. kilometers
+
+
+WEIGHT.
+
+Gram                    = 15.43 grains
+Gram                    =  0.772 U. S. apoth. scruple
+Gram                    =  0.2572 U. S. apoth. dram
+Gram                    =  0.0353 avoir. ounce
+Gram                    =  0.03215 troy ounce
+Kilogram                =  2.205 avoir. pounds
+Kilogram                =  2.679 troy pounds
+Metric ton              =  0.984 gross or long ton
+Metric ton              =  1.102 short or net tons
+Grain                   =  0.064 gram
+U. S. apoth. scruple    =  1.296 grams
+U. S. apoth. dram       =  3.89 grams
+Avoir. ounce            = 28.35 grams
+Troy ounce              = 31.10 grams
+Avoir. pound            =  0.4536 kilogram
+Troy pound              =  0.373 kilogram
+Gross or long ton       =  1.016 metric tons
+Short or net ton        =  0.907 metric ton
+
+
+VOLUME.
+
+Cu. centimeter          =  0.0610 cu. inch
+Cu. meter               = 35.3 cu. feet
+Cu. meter               =  1.308 cu. yards
+Cu. inch                = 16.39 cu. centimeters
+Cu. foot                =  0.283 cu. meter
+Cu. yard                =  0.765 cu. meter
+
+
+CAPACITY.
+
+Millimeter             =  0.0338 U. S. liq. ounce
+Millimeter             =  0.2705 U. S. apoth. dram
+Liter                  =  1.057  U. S. liq. quarts
+Liter                  =  0.2642 U. S. liq. gallon
+Liter                  =  0.908  U. S. dry quart
+Dekaliter              =  1.135  U. S. pecks
+Hectoliter             =  2.838  U. S. bushels
+U. S. liq. ounce       = 29.57   millimeters
+U. S. apoth. dram      =  3.70   millimeters
+U. S. liq. quarts      =  0.946  liter
+U. S. dry quarts       =  1.101  liters
+U. S. liq. gallon      =  3.785  liters
+U. S. peck             =  0.881  dekaliter
+U. S. bushel           =  0.3524 hectoliter
+
+
+AVOIRDUPOIS WEIGHT.
+
+1 pound = 16 ounces = 256 drams
+           1 ounce  =  16   "
+
+
+TROY (APOTHECARIES') WEIGHT (U. S.)
+
+1 pound = 12 ounces = 96 drams = 288 scruples = 5,760 grains
+          1 ounce  =  8 drams =  24 scruples =   480 grains
+                       1 dram =   3 scruples =    60 grains
+                                  1 scruple  =    20 grains
+
+
+WINE (APOTHECARIES) LIQUID MEASURE (U. S.)
+
+1 gallon = 8 pints = 128 fl. ozs. = 1,024 fl. drams = 61,440 minims
+           1 pint  =  16 fl. ozs. =   128 fl. drams =  7,689 minims
+                       1 fl. oz.  =     8 fl. drams =    480 minims
+                                        1 fl. dram  =     60 minims
+
+_To find diameter of a circle_ multiply circumference by .31831.
+
+_To find circumference of a circle_, multiply diameter by 3.1416.
+
+_To find area of a circle_, multiply square of diameter by .7854.
+
+_To find surface of a ball_, multiply square of diameter by 3.1416.
+
+_To find side of an equal square_, multiply diameter by .8862.
+
+_To find cubic inches in a ball_, multiply cube of diameter by .5236.
+
+_Doubling the diameter of a pipe_, increases its capacity four times.
+
+_One cubic foot of anthracite coal_ weighs about 53 lbs.
+
+_One cubic foot of bituminous coal_ weighs from 47 to 50 pounds.
+
+_A gallon of water_ (U. S. standard) weighs 8-1/3 pounds and contains
+231 cubic inches.
+
+_A cubic foot of water_ contains 7-1/2 gallons, 1728 cubic inches and
+weighs 62-1/2 pounds.
+
+_To find the number of pounds of water a cylindrical_ tank contains,
+square the diameter, multiply by .785 and then by the height in feet.
+This gives the number of cubic feet which multiplied by 62-1/2 gives the
+capacity in pounds of water. Divide by 7-1/2 and this gives the capacity
+in gallons.
+
+_A horse-power_ is equivalent to raising 33,000 pounds 1 foot per
+minute, or 550 pounds 1 foot per second.
+
+_The friction of water in pipes_ is as the square of velocity. The
+capacity of pipes is as the square of their diameters; thus, doubling
+the diameter of a pipe increases its capacity four times.
+
+_To find the diameter of a pump cylinder_ to move a given quantity of
+water per minute (100 feet of piston being the standard of speed),
+divide the number of gallons by 4, then extract the square root, and the
+product will be the diameter in inches of the pump cylinder.
+
+_To find the horse-power necessary to elevate water_ to a given height,
+multiply the weight of the water elevated per minute in pounds by the
+height in feet, and divide the product by 33,000 (an allowance should be
+added for water friction, and a further allowance for loss in steam
+cylinder, say from 20 to 30 per cent).
+
+_To compute the capacity of pumping engines_, multiply the area of water
+piston, in inches, by the distance it travels, in inches, in a given
+time. Deduct 3 per cent for slip and rod displacement. The product
+divided by 231 gives the number of gallons in time named.
+
+_To find the velocity in feet per minute_ necessary to discharge a given
+volume of water in a given time, multiply the number of cubic feet of
+water by 144 and divide the product by the area of the pipe in inches.
+
+_To find the area of a required pipe_, the volume and velocity of water
+being given, multiply the number of cubic feet of water by 144 and
+divide the product by the velocity in feet per minute. The area being
+found, the diameter can be learned by using any table giving the "area
+of circles" and finding the nearest area, opposite to which will be
+found the diameter to correspond.
+
+
+Physical and Chemical Constants of Fixed Oils and Fats.
+
+(FROM LEWKOWITSCH AND OTHER AUTHORITIES.)
+
+______________________________________________________________________________
+                       |            |          |             |               |
+                       |  Specific  |Specific  |   Melting-  |Solidifying-   |
+                       |  gravity   | gravity  |    point.   |    point.     |
+                       |  at 15°C.  | at 100°C.|      C.     |       C.      |
+_______________________|____________|__________|_____________|_______________|
+                       |            |          |             |               |
+Linseed oil            | 0.931-0.938|  0.880   | -16° to -26°|      -16°     |
+Hemp-seed oil          | 0.925-0.931|          |             |      -27°     |
+Walnut oil             | 0.925-0.926|  0.871   |             |      -27°     |
+Poppy-seed oil         | 0.924-0.927|  0.873   |             |      -18°     |
+Sunflower oil          | 0.924-0.926|  0.919   |             |      -17°     |
+Fir-seed oil           | 0.925-0.928|          |             |  -27° to -30° |
+Maize oil              | 0.921-0.926|          |             |  -10° to -15° |
+Cotton-seed oil        | 0.922-0.930|  0.867   |             |      12°      |
+Sesame oil             | 0.923-0.924|  0.871   |             |      -5°      |
+Rape-seed oil          | 0.914-0.917|  0.863   |             |  -2° to -10°  |
+Black mustard oil      | 0.916-0.920|          |             |     -17.5°    |
+Croton oil             | 0.942-0.955|          |             |      -16°     |
+Castor oil             | 0.960-0.966|  0.910   |             |  -12° to -18° |
+Apricot-kernel oil     | 0.915-0.919|          |             |      -14°     |
+Almond oil |           | 0.915-0.920|          |             |  -10° to -20° |
+Peanut (arachis) oil   | 0.916-0.920|  0.867   |             |   -3° to -7°  |
+Olive oil              | 0.914-0.917|  0.862   |             |       2°      |
+Menhaden oil           | 0.927-0.933|          |             |      -4°      |
+Cod-liver oil          | 0.922-0.927|  0.874   |             |   0° to -10°  |
+Seal oil               | 0.924-0.929|  0.873   |             |       3°      |
+Whale oil              | 0.920-0.930|  0.872   |             |      -2°      |
+Dolphin oil            | 0.917-0.918|          |             |   5° to -3°   |
+Porpoise oil           |    0.926   |  0.871   |             |      -16°     |
+Neat's-foot oil        | 0.914-0.916|  0.861   |             |   0° to 1.5°  |
+Cotton-seed stearine   | 0.919-0.923|  0.867   |      40°    |  31° to 32.5° |
+Palm oil               | 0.921-0.925|  0.856   |  27° to 42° |               |
+Cacao butter           | 0.950-0.952|  0.858   |  30° to 33° |   25° to 26°  |
+Cocoa-nut oil          | 0.925-0.926|  0.873   |  20° to 26° |   16° to 20°  |
+Myrtle wax             |    0.995   |  0.875   |  40° to 44° |   39° to 43°  |
+Japan wax              | 0.970-0.980|  0.875   | 51° to 54.5°|      46°      |
+Lard                   | 0.931-0.938|  0.861   |  41° to 46° |      29°      |
+Bone fat               | 0.914-0.916|          |  21° to 22° |   15° to 17°  |
+Tallow                 | 0.943-0.952|  0.860   |  42° to 46° |   35° to 37°  |
+Butter fat             | 0.927-0.936|  0.866   | 29.5° to 33°|   19° to 20°  |
+Oleomargarine          | 0.924-0.930|  0.859   |             |               |
+Sperm oil              | 0.875-0.884|  0.833   |             |      -25°     |
+Bottle-nose oil        | 0.879-0.880|  0.827   |             |               |
+Carnauba wax           | 0.990-0.999|  0.842   |  84° to 85° |   80° to 81°  |
+Wool-fat               |    0.973   |  0.901   |  39° to 42° |  30° to 30.2° |
+Beeswax                | 0.958-0.969|  0.822   |  62° to 64° |  60.5° to 62° |
+Spermaceti             |    0.960   |  0.812   | 43.5° to 49°| 43.4° to 44.2°|
+Chinese wax            |    0.970   |  0.810   | 80.5° to 81°|  80.5° to 81° |
+Tung (Chinese wood oil)| 0.936-0.942|          |             |   below -17°  |
+Soya-bean oil          | 0.924-0.927|          |             |    8° to 15°  |
+_______________________|____________|__________|_____________|_______________|
+
+
+Physical and Chemical Constants of Fixed Oils and Fats.
+
+(FROM LEWKOWITSCH AND OTHER AUTHORITIES.)
+
+Column Headings:
+A: Saponification value.
+B: Maumené test.
+C: Iodine value.
+D: Hehner value.
+E: Reichert value.
+
+______________________________________________________________________________
+                   |             |             |            |         |      |
+                   |     [A]     |     [B]     |     [C]    |   [D]   | [E]  |
+___________________|_____________|_____________|____________|_________|______|
+                   |             |             |            |         |      |
+Linseed oil        |   190-195   |  104°-111°  |   175-190  |         |      |
+Hemp-seed oil      |   190-193   |   95°-96°   |     148    |         |      |
+Walnut oil         |     195     |   96°-101°  |   144-147  |         |      |
+Poppy-seed oil     |     195     |   86°-88°   |   134-141  |  95.38  |      |
+Sunflower oil      |   193-194   |   72°-75°   |   120-129  |    95   |      |
+Fir-seed oil       |    191.3    |   98°-99°   | 118.9-120  |         |      |
+Maize oil          |   188-193   |  56°-60.5°  |  117-125   | 89-95.7 | 2.5  |
+Cotton-seed oil    |   191-195   |   68°-77°   |  104-110   |  96-17  |      |
+Sesame oil         |   189-193   |   64°-68°   |  105-109   |  95.8   | 0.35 |
+Rape-seed oil      |   170-178   |   51°-60°   |   95-105   |    95   |      |
+Black mustard oil  |  174-174.6  |   43°-44°   |   96-110   |  95.05  |      |
+Croton oil         | 210.3-215   |             | 101.7-104  |    89   | 13.5 |
+Castor oil         |   178-186   |   46°-47°   |  83.4-85.9 |         | 1.4  |
+Apricot-kernel oil | 192.2-193.1 |  42.5°-46°  |   100-107  |         |      |
+Almond oil         | 190.5-195.4 |   51°-54°   |    93-97   |  96.2   |      |
+Peanut (arachis)   |             |             |            |         |      |
+  oil              |   190-197   |   45°-49°   |    85-98   |  95.86  |      |
+Olive oil          |   191-196   | 41.5°-45.5° |  80.6-84.5 |  95.43  | 0.3  |
+Menhaden oil       | 189.3-192   |  123°-128°  |   140-170  |         | 1.2  |
+Cod-liver oil      |   182-187   |  102°-103°  |   154-180  |  95.3   |      |
+Seal oil           |   190-196   |     92°     |   127-140  |  94.2   | 0.22 |
+Whale-oil          |   188-193   |   91°-92°   |   110-136  |  93.5   | 2.04 |
+Dolphin  {Body oil |    197.3    |             |    99.5    |  93.07  | 5.6  |
+  oil    {Jaw oil  |     200     |             |    32.8    |  66.28  |65.92 |
+Porpoise {Body oil |   216-218.8 |     50°     |   119.4    |         |23.45 |
+  oil    {Jaw oil  |    253.7    |             |    49.6    |  68.41  |65.8  |
+Neat's-foot oil    |    194.3    |  47°-48.5°  |  69.3-70.4 |         |      |
+Cotton-seed        |             |             |            |         |      |
+  stearine.        | 194.6-195.1 |     48°     |  88.7-92.8 |  96.3   |      |
+Palm oil           | 196.3-202   |             |    53-57   |  95.6   | 0.5  |
+Cacao butter       | 192.2-193.5 |             |    32-41   |  94.59  | 1.6  |
+Cocoa-nut oil      |   250-253   |             |   8.5-9.3  |  88.6   | 3.7  |
+Myrtle wax         | 205.7-211.7 |             |     2.9    |         |      |
+Japan wax          |   220-222.4 |             |   4.2-8.5  |  90.6   |      |
+Lard               | 195.3-196.6 |   27°-32°   |    57-70   |   96    |      |
+Bone fat           |    190.9    |             |  46.3-49.6 |         |      |
+Tallow             |   195-198   |             |    36-47   |  95.6   | 0.25 |
+Butter fat         | 221.5-227   |             |    26-35   |  87.5   |28.78 |
+Oleomargarine      |   194-203.7 |             |   55.3-60  |  95-96  | 2.6  |
+Sperm oil          | 132.5-147   |   47°-51°   |     84     |         | 1.3  |
+Bottle-nose oil    |   126-134   |   41°-47°   |   77.4-82  |         | 1.4  |
+Carnauba wax       |    80-84    |             |    13.5    |         |      |
+Wool-fat           |  98.2-102.4 |             |    25-28   |         |      |
+Beeswax            |    91-96    |             |   8.3-11   |         |      |
+Spermaceti         |     128     |             |            |         |      |
+Chinese wax        |     63      |             |            |         |      |
+Tung (Chinese      |             |             |            |         |      |
+  wood oil)        |     193     |             |   150-165  |         |      |
+Soya-bean oil      | 190.6-192.9 |   59°-61°   | 121.3-124  |  95.5   |      |
+___________________|_____________|_____________|____________|_________|______|
+
+
+*Temperature Correction Table for Hehner's Concentrated Bichromate
+Solution for Glycerine Analysis
+
+__________________________________________
+            |                  |
+     A      |         f        |
+Temperature | Corrected Volume | Logarithm
+            |       1 c.c.     |
+____________|__________________|__________
+            |                  |
+   11° C    |    0.9980 ccm    |   99913
+   12° "    |    0.9985 "      |   99935
+   13° "    |    0.9990 "      |   99956
+   14° "    |    0.9995 "      |   99978
+   15° "    |    1.0000 "      |   00000
+   16° "    |    1.0005 "      |   00022
+   17° "    |    1.0010 "      |   00043
+   18° "    |    1.0015 "      |   00065
+   19° "    |    1.0020 "      |   00087
+   20° "    |    1.0025 "      |   00108
+   21° "    |    1.0030 "      |   00130
+   22° "    |    1.0035 "      |   00152
+   23° "    |    1.0040 "      |   00173
+____________|__________________|__________
+
+
+*Table of Important Fatty Acids
+
+_______________________________________________________________________________
+           |                   |      |                      |       |
+           |                   |      |     Boiling Point    |       |
+           |                   |      |______________________|       |Neutral-
+           |                   | Mol. |          |           | Melt- |ization
+   Name    |      Formula      | Wt.  | Ordinary |  100 mm   |  ing  |value
+           |                   |      | Pressure | Pressure  |   Pt. | Mg. KOH
+___________|___________________|______|__________|___________|_______|__________
+           |                   |      |          |           |       |
+Butyric    | C_{4}H_{8}O_{2}   |  88  |  162.3   |           |       |637.5
+Caproic    | C_{6}H_{12}O_{2}  | 116  |  199.7   |           |       |483.6
+Caprylic   | C_{8}H_{16}O_{2}  | 144  | 236-237  |           | 16.5  |389.6
+Capric     | C_{10}H_{20}O_{2} | 172  | 268-270  | 199.5-200 | 31.3  |326.2
+Lauric     | C_{12}H_{24}O_{2} | 200  |          |    225    | 43.6  |280.5
+Myristic   | C_{14}H_{28}O_{2} | 228  |          |   250.5   | 53.8  |246.1
+Palmitic   | C_{16}H_{32}O_{2} | 256  |          |   268.5   |  62   |219.1
+Stearic    | C_{18}H_{36}O_{2} | 284  |          |    291    |  69.2 |197.5
+Arachidic  | C_{20}H_{40}O_{2} | 302  |          |           |  75   |185.8
+Behenic    | C_{22}H_{44}O_{2} | 330  |          |           | 77-78 |170.0
+Cerotic    | C_{27}H_{54}O_{2} | 400  |          |           |  78   |140.25
+Melissic   | C_{30}H_{60}O_{2} | 442  |          |           |  90   |126.5
+Oleic      | C_{18}H_{34}O_{2} | 282  |          | 185.5-286 |  14   |198.9
+Erucic     | C_{22}H_{42}O_{2} | 338  |          |           | 33-34 |165.9
+Linolic    | C_{18}H_{32}O_{2} | 280  |          |           |       |200.4
+Linolenic  | C_{18}H_{30}O_{2} | 278  |          |           |       |201.5
+Ricinoleic | C_{18}H_{34}O_{3} | 298  |          |           |       |181.6
+___________|___________________|______|__________|___________|_______|__________
+
+
+*Comparison of Thermometer Scales
+
+n Degree Celsius = 4/5n Degree Reaumur = 32 + 9/5n Degree Fahrenheit
+
+n Degree Reaumur = 5/4n Degree Celsius = 32 + 9/4n Degree Fahrenheit
+
+n Degree Fahrenheit = 5/9 (n - 32) Degree Celsius = 4/9 (n - 32) Deg. R
+
+=============================================================================
+ C.   R.     F.     |  C.  R.    F.    | C.  R.    F.     |  C.   R.     F.
+--------------------|------------------|------------------|------------------
+-20  -16     -4     | 20  16     68    | 60  48    140    | 100   80    212
+-19  -15.2   -2.2   | 21  16.8   69.8  | 61  48.8  141.8  | 101   80.8 213.8
+-18  -14.4   -0.4   | 22  17.6   71.6  | 62  49.6  143.6  | 102   81.6 215.6
+-17  -13.6    1.4   | 23  18.4   73.4  | 63  50.4  145.4  | 103   82.4 217.4
+-16  -12.8    3.2   | 24  19.2   75.2  | 64  51.2  147.2  | 104   83.2 219.2|
+                    |                  |                  |
+-15  -12      5     | 25  20     77    | 65  52    149    | 105   84    221
+-14  -11.2    6.8   | 26  20.8   78.8  | 66  52.8  150.8  | 106   84.8 222.8
+-13  -10.4    8.6   | 27  21.6   80.6  | 67  53.6  152.6  | 107   85.6 224.6
+-12   -9.6   10.4   | 28  22.4   82.4  | 68  54.4  154.4  | 108   86.4 226.4
+-11   -8.8   12.2   | 29  23.2   84.2  | 69  55.2  156.2  | 109   87.2 228.2
+                    |                  |                  |
+-10   -8     14     | 30  24     86    | 70  56    158    | 110   88    230
+ -9   -7.2   15.8   | 31  24.8   87.8  | 71  56.8  159.8  | 111   88.8 231.8
+ -8   -6.4   17.6   | 32  25.6   89.6  | 72  57.6  161.6  | 112   89.6 233.6
+ -7   -5.6   19.4   | 33  26.4   91.4  | 73  58.4  163.4  | 113   90.4 235.4
+ -6   -4.8   21.2   | 34  27.2   93.2  | 74  59.2  165.2  | 114   91.2 237.2
+                    |                  |                  |
+ -5   -4     23     | 35  28     95    | 75  60    167    | 115   92    239
+ -4   -3.2   24.8   | 36  28.8   96.8  | 76  60.8  168.8  | 116   92.8 240.8
+ -3   -2.4   26.6   | 37  29.6   98.6  | 77  61.6  170.6  | 117   93.6 242.6
+ -2   -1.6   28.4   | 38  30.4  100.4  | 78  62.4  172.4  | 118   94.4 244.4
+ -1   -0.8   30.2   | 39  31.2  102.2  | 79  63.2  174.2  | 119   95.2 246.2
+                    |                  |                  |
+  0    0     32     | 40  32    104    | 80  64    176    | 120   96    248
+  1    0.8   33.8   | 41  32.8  105.8  | 81  64.8  177.8  | 121   96.8 249.8
+  2    1.6   35.6   | 42  33.6  107.6  | 82  65.6  179.6  | 122   97.6 252.6
+  3    2.4   37.4   | 43  34.4  109.4  | 83  66.4  181.4  | 123   98.4 253.4
+  4    3.2   39.2   | 44  35.2  111.2  | 84  67.2  183.2  | 124   99.2 255.2
+                    |                  |                  |
+  5    4     41     | 45  36    113    | 85  68    185    | 125  100    257
+  6    4.8   42.8   | 46  36.8  114.8  | 86  68.8  186.8  | 126  100.8 258.8
+  7    5.6   44.6   | 47  37.6  116.6  | 87  69.6  188.6  | 127  101.6 260.6
+  8    6.4   46.4   | 48  38.4  118.4  | 88  70.4  190.4  | 128  102.4 262.4
+  9    7.2   48.2   | 49  39.2  120.2  | 89  71.2  192.2  | 129  103.2 264.2
+                    |                  |                  |
+ 10    8     50     | 50  40    122    | 90  72    194    | 130  104    266
+ 11    8.8   51.8   | 51  40.8  123.8  | 91  72.8  195.8  | 131  104.8 267.8
+ 12    9.6   53.6   | 52  41.6  125.6  | 92  73.6  197.6  | 132  105.6 269.6
+ 13   10.4   55.4   | 53  42.4  127.4  | 93  74.4  199.4  | 133  106.4 271.4
+ 14   11.2   57.2   | 54  43.2  129.2  | 94  75.2  201.2  | 134  107.2 273.2
+                    |                  |                  |
+ 15   12     59     | 55  44    131    | 95  76    203    | 135  108    275
+ 16   12.8   60.8   | 56  44.8  132.8  | 96  76.8  204.8  | 136  108.8 276.8
+ 17   13.6   62.6   | 57  45.6  134.6  | 97  77.6  206.6  | 137  109.6 278.6
+ 18   14.4   64.4   | 58  46.4  136.4  | 98  78.4  208.4  | 138  110.4 280.4
+ 19   15.2   66.2   | 59  47.2  138.2  | 99  79.2  210.2  | 139  111.2 282.2
+===============================================================================
+
+
+*Quantities of Alkali Required for Saponification of Fats of Average
+Molecular Weight 670
+
+(Cocoanut Oil, Palmkernel Oil)
+
+_________________________________________________
+      |                     |                   |
+      |    Liters Alkali    |   Liters Alkali   |
+      |      Solution       |     Solution      |
+Kilos |     Sp. Gr. 1.1     |    Sp. Gr. 1.2    |
+______|_____________________|___________________|
+      |          |          |         |         |
+      |   NaOH   |    KOH   |   NaOH  |   KOH   |
+______|__________|__________|_________|_________|
+      |          |          |         |         |
+ 1000 |  1875.83 |  1902.99 |  844.67 |  930.35 |
+ 2000 |  3751.66 |  3805.97 | 1689.35 | 1860.70 |
+ 3000 |  5627.50 |  5708.96 | 2534.02 | 2791.04 |
+ 4000 |  7508.33 | 7611.94  | 3378.69 | 3721.39 |
+ 5000 |  9379.16 |  9514.93 | 4223.37 | 4651.74 |
+ 6000 | 11254.99 | 11417.91 | 5068.04 | 5582.09 |
+ 7000 | 13130.82 | 13320.90 | 5912.71 | 6512.44 |
+ 8000 | 15006.66 | 15223.88 | 6757.38 | 7442.78 |
+ 9000 | 16882.49 | 17126.87 | 7602.06 | 8373.13 |
+10000 | 18758.32 | 19029.85 | 8446.73 | 9303.48 |
+______|__________|__________|_________|_________|
+
+______________________________________________
+      |                   |
+      |   Liters Alkali   |  Liters Alkali
+      |     Solution      |    Solution
+Kilos |    Sp. Gr. 1.3    |  Sp. Gr. 1.355
+______|___________________|___________________
+      |         |         |         |
+      |   NaOH  |   KOH   |   NaOH  |   KOH
+______|_________|_________|_________|_________
+      |         |         |         |
+ 1000 |  510.27 |  622.71 |  409.61 |  517.97
+ 2000 | 1020.54 | 1245.41 |  819.21 | 1035.95
+ 3000 | 1530.81 | 1868.12 | 1228.82 | 1553.92
+ 4000 | 2041.01 | 2490.83 | 1638.43 | 2071.90
+ 5000 | 2551.35 | 3113.54 | 2048.04 | 2589.87
+ 6000 | 3061.61 | 3736.24 | 2457.65 | 3107.84
+ 7000 | 3571.88 | 4358.95 | 2867.26 | 3625.82
+ 8000 | 4082.15 | 4981.66 | 3276.86 | 4143.79
+ 9000 | 4592.42 | 5604.36 | 3886.47 | 4661.77
+10000 | 5102.69 | 6227.02 | 4096.08 | 5179.74
+______|_________|_________|_________|_________
+
+
+*Quantities of Alkali Required for Saponification of Fats of Average
+Molecular Weight 860
+
+(Tallow, Cottonseed Oil, Olive Oil, Etc.)
+
+_________________________________________________
+      |                     |                   |
+      |    Liters Alkali    |   Liters Alkali   |
+      |      Solution       |     Solution      |
+Kilos |     Sp. Gr. 1.1     |    Sp. Gr. 1.2    |
+______|_____________________|___________________|
+      |          |          |         |         |
+      |   NaOH   |    KOH   |   NaOH  |   KOH   |
+______|__________|__________|_________|_________|
+      |          |          |         |         |
+ 1000 |  1461.40 |  1482.56 |  658.05 |  724.81 |
+ 2000 |  2922.81 |  2965.12 | 1316.12 | 1449.61 |
+ 3000 |  4384.21 |  4447.67 | 1974.18 | 2174.42 |
+ 4000 |  5845.62 |  5930.23 | 2632.24 | 2899.22 |
+ 5000 |  7307.02 |  7412.79 | 3290.80 | 3624.03 |
+ 6000 |  8768.42 |  8895.85 | 3948.35 | 4348.84 |
+ 7000 | 10229.83 | 10377.91 | 4606.41 | 5073.64 |
+ 8000 | 11691.23 | 11860.45 | 5264.47 | 5798.45 |
+ 9000 | 13152.64 | 13343.02 | 5922.53 | 6523.25 |
+10000 | 14614.04 | 14825.58 | 6580.59 | 7248.06 |
+______|__________|__________|_________|_________|
+______________________________________________
+      |                   |
+      |   Liters Alkali   |  Liters Alkali
+      |     Solution      |    Solution
+Kilos |    Sp. Gr. 1.3    |  Sp. Gr. 1.355
+______|___________________|___________________
+      |         |         |         |
+      |   NaOH  |   KOH   |   NaOH  |   KOH
+______|_________|_________|_________|_________
+      |         |         |         |
+ 1000 |  397.54 |  485.13 |  319.11 |  403.54
+ 2000 |  795.07 |  970.27 |  638.23 |  807.08
+ 3000 | 1192.61 | 1455.40 |  957.34 | 1210.61
+ 4000 | 1590.14 | 1940.53 | 1276.45 | 1614.15
+ 5000 | 1987.68 | 2425.67 | 1595.57 | 2017.69
+ 6000 | 2385.21 | 2910.80 | 1914.68 | 2421.23
+ 7000 | 2782.75 | 3395.93 | 2233.79 | 2824.77
+ 8000 | 3180.28 | 3881.06 | 2552.90 | 3228.30
+ 9000 | 3577.82 | 4366.20 | 2872.02 | 3631.84
+10000 | 3975.35 | 4851.33 | 3191.13 | 4035.38
+______|_________|_________|_________|_________
+
+
+DENSITY AND STRENGTH OF SULPHURIC ACID (SIDERSKY).
+
+Column Headings:
+A: Degrees Twaddell
+B: Sp. Gr. at 15° C.
+C: % of pure acid (H_{2}SO_{4}).
+D: Equivalent (in cc.) of a kilo of pure acid.
+E: Equivalent (in cc.) of a liter of pure acid.
+
+
+=========================================
+
+ [A]    [B]     [C]      [D]        [E]
+_________________________________________
+
+1     1.007     1.9     52.620     96.930
+3     1.014     2.8     35.710     66.450
+4     1.022     3.8     25.650     47.230
+6     1.029     4.8     20.410     37.582
+8     1.037     5.8     16.670     30.690
+9     1.045     6.8     14.085     25.938
+10    1.052     7.8     12.198     22.460
+12    1.062     8.8     10.755     19.803
+13    1.067     9.8      9.524     17.540
+15    1.075    10.9      8.547     15.740
+17    1.083    11.9      7.752     14.278
+18    1.091    13.0      7.042     12.969
+20    1.100    14.1      6.452     11.882
+22    1.108    15.2      5.953     10.962
+23    1.116    16.2      5.526     10.177
+25    1.125    17.3      5.405      9.954
+27    1.134    18.5      4.76       8.770
+29    1.142    19.6      4.465      8.223
+30    1.152    20.8      4.184      7.723
+32    1.162    22.2      3.876      7.138
+34    1.171    23.3      3.663      6.745
+36    1.180    24.5      3.541      6.521
+38    1.190    25.8      3.258      5.999
+40    1.200    27.1      3.077      5.666
+42    1.210    28.4      2.907      5.353
+44    1.220    29.6      2.770      5.102
+46    1.231    31.0      2.618      4.865
+48    1.241    32.2      2.500      4.604
+50    1.252    33.4      2.392      4.406
+53    1.263    34.7      2.283      4.205
+55    1.274    36.0      2.179      4.012
+57    1.285    37.4      2.079      3.829
+60    1.297    38.8      1.988      3.661
+62    1.308    40.2      1.905      3.508
+64    1.320    41.6      1.821      3.354
+66    1.332    43.0      1.745      3.214
+69    1.345    44.4      1.665      3.085
+71    1.357    45.5      1.621      2.985
+74    1.370    46.9      1.558      2.869
+77    1.383    48.3      1.497      2.757
+80    1.397    49.8      1.436      2.646
+82    1.410    51.2      1.386      2.551
+85    1.424    52.6      1.335      2.459
+88    1.438    54.0      1.287      2.370
+91    1.453    55.4      1.237      2.270
+94    1.468    56.9      1.195      2.200
+97    1.483    58.3      1.156      2.130
+100   1.498    59.6      1.116      2.050
+103   1.514    61.0      1.080      1.980
+106   1.530    62.5      1.045      1.930
+108   1.540    64.0      1.010      1.860
+113   1.563    65.5      0.975      1.800
+116   1.580    67.0      0.950      1.740
+120   1.597    68.6      0.917      1.690
+123   1.615    70.0      0.888      1.630
+127   1.634    71.6      0.855      1.570
+130   1.652    73.2      0.845      1.520
+134   1.671    74.7      0.800      1.470
+138   1.691    76.4      0.774      1.430
+142   1.711    78.1      0.749      1.390
+146   1.732    79.9      0.722      1.320
+151   1.753    81.7      0.705      1.280
+155   1.774    84.1      0.672      1.235
+160   1.798    86.5      0.639      1.190
+164   1.819    89.7      0.609      1.120
+168   1.842   100.0      0.544      1.000
+
+
+*Densities of Potassium Carbonate Solutions at 15 C (Gerlach)
+
+=======================
+        |             |
+        |  Per cent   |
+Sp. Gr. |   of pure   |
+        | K_{2}CO_{3} |
+________|_____________|
+        |             |
+1.00914 |    1        |
+1.01829 |    2        |
+1.02743 |    3        |
+1.03658 |    4        |
+1.04572 |    5        |
+1.05513 |    6        |
+1.06454 |    7        |
+1.07396 |    8        |
+1.08337 |    9        |
+1.09278 |   10        |
+1.10258 |   11        |
+1.11238 |   12        |
+1.12219 |   13        |
+1.13199 |   14        |
+1.14179 |   15        |
+1.15200 |   16        |
+1.16222 |   17        |
+1.17243 |   18        |
+1.18265 |   19        |
+1.19286 |   20        |
+1.20344 |   21        |
+1.21402 |   22        |
+1.22459 |   23        |
+1.23517 |   24        |
+1.24575 |   25        |
+1.25681 |   26        |
+1.26787 |   27        |
+1.27893 |   28        |
+1.28999 |   29        |
+1.30105 |   30        |
+1.31261 |   31        |
+1.32417 |   32        |
+1.33573 |   33        |
+1.34729 |   34        |
+1.35885 |   35        |
+1.37082 |   36        |
+1.38279 |   37        |
+1.39476 |   38        |
+1.40673 |   39        |
+1.41870 |   40        |
+1.43104 |   41        |
+1.44338 |   42        |
+1.45573 |   43        |
+1.46807 |   44        |
+1.48041 |   45        |
+1.49314 |   46        |
+1.50588 |   47        |
+1.51861 |   48        |
+1.53135 |   49        |
+1.54408 |   50        |
+1.55728 |   51        |
+1.57048 |   52        |
+1.57079 |   53.024    |
+________|_____________|
+
+
+*Constants of Certain Fatty Acids and Triglycerides
+
+=========================================================
+              |          |            |
+              |          |            |  Per cent Yield
+Triglycerides | Mol. Wt. | Mol. Wt.   |__________________
+      of      | of Fatty | of Tri-    |       |
+              | of Fatty | glycerides | Fatty | Glycerine
+              |          |            | Acid  |
+______________|__________|____________|_______|___________
+              |          |            |       |
+Stearic Acid  |    284   |     890    | 95.73 |  10.34
+Oleic Acid    |    282   |     884    | 95.70 |  10.41
+Margaric Acid |    270   |     848    | 95.52 |  10.85
+Palmitic Acid |    256   |     806    | 95.28 |  11.42
+Myristic Acid |    228   |     722    | 94.47 |  12.74
+Lauric Acid   |    200   |     638    | 94.04 |  14.42
+Capric Acid   |    172   |     594    | 93.14 |  15.48
+Caproic Acid  |    116   |     386    | 90.16 |  23.83
+Butyric Acid  |     88   |     302    | 87.41 |  30.46
+______________|__________|____________|_______|___________
+
+
+PERCENTAGES OF SOLID CAUSTIC SODA AND CAUSTIC POTASH IN CAUSTIC LYES
+ACCORDING TO BAUME SCALE.
+
+Degrees    %     %
+ Baumé.  NaOH   KOH
+
+ 1       0.61   0.90
+ 2       0.93   1.70
+ 3       2.00   2.60
+ 4       2.71   3.50
+ 5       3.35   4.50
+ 6       4.00   5.60
+ 7       4.556  6.286
+ 8       5.29   7.40
+ 9       5.87   8.20
+10       6.55   9.20
+11       7.31  10.10
+12       8.00  10.90
+13       8.68  12.00
+14       9.42  12.90
+15      10.06  13.80
+16      10.97  14.80
+17      11.84  15.70
+18      12.64  16.50
+19      13.55  17.60
+20      14.37  18.60
+21      15.13  19.50
+22      15.91  20.50
+23      16.77  21.40
+24      17.67  22.50
+25      18.58  23.30
+26      19.58  24.20
+27      20.59  25.10
+28      21.42  26.10
+29      22.64  27.00
+30      23.67  28.00
+31      24.81  28.90
+32      25.80  29.80
+33      26.83  30.70
+34      27.80  31.80
+35      28.83  32.70
+36      29.93  33.70
+37      31.22  34.90
+38      32.47  35.90
+39      33.69  36.90
+40      34.96  37.80
+41      36.25  38.90
+42      37.53  39.90
+43      38.80  40.90
+44      39.99  42.10
+45      41.41  43.40
+46      42.83  44.60
+47      44.38  45.80
+48      46.15  47.10
+49      47.58  48.25
+50      49.02  49.40
+
+
+GLYCERINE CONTENT OF MORE COMMON OILS AND FATS USED IN SOAP MAKING.
+
+   Kind.          Theoretical     Average Free     % Pure        Yield
+                 Yield of Pure   Fatty Acid in    Glycerine     Soap Lye
+                 Glycerine of      Commercial   in Commercial   80% Crude
+                  Neutral Oil        Oil.            Oil.       Glycerine.
+                    or Fat.
+
+Beef Tallow           10.7             5           10.2         12.75
+Bone Grease           10.5            20-50         5.2- 8.4     6.5-10.5
+Castor Oil             9.8           0.5-10         8.8- 9.8    11.0-12.45
+Cocoanut Oil          13.9             3-5         13.2-13.5    16.5-16.9
+Cocoanut Oil Off                      15-40         8.3-11.8    10.37-14.75
+Corn Oil              10.4             1-10         9.3-10.3    11.62-12.9
+Cottonseed Oil        10.6            Trace        10.6         13.25
+Hog Grease            10.6           0.5-1         10.5-10.6    13.12-13.25
+Horse Grease          10.6             1-3         10.5-10.6    13.12-13.25
+Olive Oil             10.3             2-25         7.7-10.2     9.62-12.75
+Olive Foots                           30-60           4-7           5-8.75
+Palm Oil              11.0            10-50         5.5-10       6.87-12.5
+Palmkernel Oil        13.3             4-8         12.2-12.8    15.25-16
+Peanut Oil            10.4             5-20         8.3-9.9     10.37-12.37
+Soya Bean Oil         10.4             2           10.2         12.75
+Train Oil             10.0             2-20           8-9.8     10.0-12.25
+Vegetable Tallow      10.9             1-3         10.5-10.8    13.12-13.5
+
+
+*Table of Specific Gravities of Pure Commercial Glycerine with
+Corresponding Percentage of Water. Temperature 15 C.
+
+------------------+------------------
+ Sp. Gr.  % Water | Sp. Gr.  % Water
+  1.262      0    |  1.160      38
+  1.261      1    |  1.157      39
+  1.258      2    |  1.155      40
+  1.255      3    |  1.152      41
+  1.2515     4    |  1.149      42
+  1.250      5    |  1.1464     43
+  1.2467     6    |  1.1437     44
+  1.2450     7    |  1.141      45
+  1.243      8    |  1.1377     46
+  1.241      9    |  1.1353     47
+  1.237     10    |  1.1326     48
+  1.235     11    |  1.1304     49
+  1.2324    12    |  1.127      50
+  1.229     13    |  1.125      51
+  1.2265    14    |  1.1224     52
+  1.2245    15    |  1.1204     53
+  1.2225    16    |  1.117      54
+  1.2185    17    |  1.114      55
+  1.2174    18    |  1.112      56
+  1.2142    19    |  1.109      57
+  1.211     20    |  1.106      58
+  1.207     21    |  1.103      59
+  1.203     22    |  1.1006     60
+  1.2004    23    |  1.088      65
+  1.198     24    |  1.075      70
+  1.195     25    |  1.0623     75
+  1.1923    26    |  1.049      80
+  1.189     27    |  1.0365     85
+  1.188     28    |  1.0243     90
+  1.1846    29    |  1.0218     91
+  1.182     30    |  1.0192     92
+  1.179     31    |  1.0168     93
+  1.176     32    |  1.0147     94
+  1.1734   33     |  1.0125     95
+  1.171    34     |  1.01       96
+  1.168    35     |  1.0074     97
+  1.165    36     |  1.0053     98
+  1.163    37     |  1.0026     99
+------------------+------------------
+
+
+Table of Percentage, Specific Gravity and Beaume Degree of Pure
+Glycerine Solutions
+
+=========+===========+===========++=========+===========+===========
+Per cent |Sp. Gr.    |Degree     ||Per cent |Sp. Gr.    |Degree
+Water    |Champion   |Beaume     ||Water    |Champion   |Beaume
+         |and Pellet |(Berthelot)||         |and Pellet |(Berthelot)
+=========+===========+===========++=========+===========+===========
+     0   |    1.2640 |      31.2 ||    11.0 |    1.2350 |      28.6
+     0.5 |    1.2625 |      31.0 ||    11.5 |    1.2335 |      28.4
+     1.0 |    1.2612 |      30.9 ||    12.0 |    1.2322 |      28.3
+     1.5 |    1.2600 |      30.8 ||    12.5 |    1.2307 |      28.2
+     2.0 |    1.2585 |      30.7 ||    13.0 |    1.2295 |      28.0
+     2.5 |    1.2575 |      30.6 ||    13.5 |    1.2280 |      27.8
+     3.0 |    1.2560 |      30.4 ||    14.0 |    1.2270 |      27.7
+     3.5 |    1.2545 |      30.3 ||    14.5 |    1.2255 |      27.6
+     4.0 |    1.2532 |      30.2 ||    15.0 |    1.2242 |      27.4
+     4.5 |    1.2520 |      30.1 ||    15.5 |    1.2230 |      27.3
+     5.0 |    1.2505 |      30.0 ||    16.0 |    1.2217 |      27.2
+     5.5 |    1.2490 |      29.9 ||    16.5 |    1.2202 |      27.0
+     6.0 |    1.2480 |      29.8 ||    17.0 |    1.2190 |      26.9
+     6.5 |    1.2465 |      29.7 ||    17.5 |    1.2177 |      26.8
+     7.0 |    1.2455 |      29.6 ||    18.0 |    1.2165 |      26.7
+     7.5 |    1.2440 |      29.5 ||    18.5 |    1.2150 |      26.5
+     8.0 |    1.2427 |      29.3 ||    19.0 |    1.2137 |      26.4
+     8.5 |    1.2412 |      29.2 ||    19.5 |    1.2125 |      26.3
+     9.0 |    1.2400 |      29.0 ||    20.0 |    1.2112 |      26.2
+     9.5 |    1.2390 |      28.9 ||    20.5 |    1.2100 |      26.0
+    10.0 |    1.2375 |      28.8 ||    21.0 |    1.2085 |      25.0
+    10.5 |    1.2362 |      28.7 ||         |           |
+=========+===========+===========++=========+===========+===========
+
+
+*Table of Specific Gravities of Pure Glycerine Solutions with
+Corresponding Beaume Degree and Percent Water
+
+--------+--------+-------+---------+--------+--------
+Per cent| Sp. Gr.| Degree| Percent | Sp. Gr.| Degree
+Water   |        | Beaume|  Water  |        | Beaume
+--------+--------+-------+---------+--------+--------
+        |        |       |         |        |
+  0.0   | 1.2640 |  31.2 |    1.0  | 1.2612 |  30.9
+  0.5   | 1.2625 |  31.0 |    1.5  | 1.2600 |  30.8
+  2.0   | 1.2585 |  30.7 |   12.0  | 1.2322 |  28.3
+  2.5   | 1.2575 |  30.6 |   12.5  | 1.2307 |  28.2
+  3.0   | 1.2560 |  30.4 |   13.0  | 1.2295 |  28.0
+  3.5   | 1.2545 |  30.3 |   13.5  | 1.2280 |  27.8
+  4.0   | 1.2532 |  30.2 |   14.0  | 1.2270 |  27.7
+  4.5   | 1.2520 |  30.1 |   14.5  | 1.2255 |  27.6
+  5.0   | 1.2505 |  30.0 |   15.0  | 1.2242 |  27.4
+  5.5   | 1.2490 |  29.9 |   15.5  | 1.2230 |  27.3
+  6.0   | 1.2480 |  29.8 |   16.0  | 1.2217 |  27.2
+  6.5   | 1.2465 |  29.7 |   16.5  | 1.2202 |  27.0
+  7.0   | 1.2455 |  29.6 |   17.0  | 1.2190 |  26.9
+  7.5   | 1.2440 |  29.5 |   17.5  | 1.2177 |  26.8
+  8.0   | 1.2427 |  29.3 |   18.0  | 1.2165 |  26.7
+  8.5   | 1.2412 |  29.2 |   18.5  | 1.2150 |  26.5
+  9.0   | 1.2400 |  29.0 |   19.0  | 1.2137 |  26.4
+  9.5   | 1.2390 |  28.9 |   19.5  | 1.2125 |  26.3
+ 10.0   | 1.2375 |  28.8 |   20.0  | 1.2112 |  26.2
+ 10.5   | 1.2362 |  28.7 |   20.5  | 1.2100 |  26.0
+ 11.0   | 1.2350 |  28.6 |   21.0  | 1.2085 |  25.9
+ 11.5   | 1.2335 |  28.4 |         |        |
+--------+--------+-------+---------+--------+--------
+
+
+
+
+INDEX
+
+
+A
+
+Acetin process for the determination of glycerol, 155.
+
+Acid, Clupanodonic, 20.
+
+Acid, Hydrochloric, 111.
+
+Acid, Lauric, 2.
+
+Acid, Myristic, 2.
+
+Acid, Napthenic, 24.
+
+Acid, Oleic, 15, 19.
+
+Acid, Palmitic, 2.
+
+Acid, Pinic, 22.
+
+Acid, Resin, 144.
+
+Acid, Stearic, 15, 19.
+
+Acid, Sulfuric, 112.
+
+Acid, Sylvic, 22.
+
+Acid saponification, 120.
+
+Air bleaching of palm oil, 12.
+
+Albuminous matter, Removal from tallow, 6.
+
+Alcohol, Denatured, 82.
+
+Alcoholic method for free alkali in soap, 139.
+
+Alkali Blue 6 B, indicator, 129.
+
+Alkali, Total, determination of in soap, 147.
+
+Alkalis, 25.
+
+Alkalis used in soap making,
+  Testing of, 134.
+
+Amalgamator, 33.
+
+Analysis, Glycerine, International, 150.
+
+Analysis, Soap, 137.
+
+Analysis, Standard methods for fats and oils, 165-196.
+
+Aqueous saponification, 121.
+
+Arachis oil, 79.
+
+Autoclave saponification, 118.
+
+Automobile soaps, 41.
+
+
+B
+
+Barrels, sampling, 168.
+
+Baumé scale, 25.
+
+Bayberry wax, Use in shaving soap, 89.
+
+Bichromate Process for glycerol determination, 160.
+
+Bleaching, Fullers' earth process for tallow, 4.
+
+Bleaching palm oil by bichromate method, 9.
+
+Bleaching palm oil by air, 12.
+
+Bosshard & Huggenberg method for determination of free alkali, 140.
+
+Bunching of soap, 52.
+
+
+C
+
+Candelite, 96.
+
+Candle tar, 125.
+
+Carbolic soap, 77.
+
+Carbon Dioxide, Formation of in carbonate saponification, 45.
+
+Carbonate, potassium, 29.
+
+Carbonate, saponification, 35, 45.
+
+Carbonate, sodium, 28.
+
+Castile soap, 79.
+
+Castor oil ferment, 121.
+
+Castor oil, Use of in transparent soaps, 83.
+
+Caustic potash, 26.
+
+Caustic potash, Electrolytic, 27.
+
+Caustic soda, 26.
+
+Changes in soap-making, 36.
+
+Chemist, Importance of, 127.
+
+Chipper, Soap, 32.
+
+Chip soap, 54.
+
+Chip soap, Cold made, 55.
+
+Chip soap, Unfilled, 56.
+
+Chrome bleaching of palm oil, 9.
+
+Cloud test for oil, Standard method, 182-183.
+
+Clupanodonic acid, 20.
+
+Cocoanut oil, 6.
+
+Cold cream soap, 78.
+
+Cold made chip soaps, 55.
+
+Cold made toilet soaps, 72.
+
+Cold made transparent soaps, 84.
+
+Cold process, 35, 43.
+
+Colophony, 22.
+
+Coloring soap, 75.
+
+Copra, 7.
+
+Corn oil, 14.
+
+Corrosive sublimate, 78.
+
+Cotton goods. Soaps used for, 103.
+
+Cottonseed oil, 14.
+
+Cream, Shaving, 90.
+
+Crude glycerine, 113.
+
+Crutcher, 32.
+
+Curd soap, 71.
+
+Cutting table, 32.
+
+
+D
+
+Determination of free fatty acid, 128.
+
+Determination of unsaponifiable matter, 132.
+
+Distillation of fatty acids, 125.
+
+Drying machine, 32.
+
+
+E
+
+Enzymes, 17.
+
+Eschweger soap, 81.
+
+Examination of fats and oils, 128.
+
+
+F
+
+Fahrion's method for moisture, 138.
+
+Fats and oils, Examination of, 128.
+
+Fats and oils used in soap manufacture, 3.
+
+Fatty acids, 14.
+
+Fatty acids, Distillation of, 125.
+
+Ferments, Splitting fats with, 121.
+
+Fillers for laundry soaps, 53.
+
+Fillers for soap powders, 58.
+
+Finishing change, 36.
+
+Fish oils, 20.
+
+Floating soap, 62.
+
+Formaldehyde soap, 78.
+
+Frames, 31.
+
+Free alkali in soap, Determination of, 139.
+
+Free fatty acid, Determination of, 128.
+
+Free fatty acids, Extraction from tallow, 6.
+
+Free fatty acid, Standard method of dilu., 174.
+  Note on method, 188-189.
+
+Full boiled soaps, 35.
+
+Fullers' earth bleaching of tallow, 4.
+
+
+G
+
+Glycerides, 2.
+
+Glycerine, 2.
+
+Glycerine analysis, 150.
+
+Glycerine change, 36.
+
+Glycerine, Crude, 113.
+
+Glycerine in spent lyes, Recovery of, 106.
+
+Glycerine in soap, Determination of, 149.
+
+Glycerine, Sampling crude, 162.
+
+Glycerine soaps, 83.
+
+Glycerol content, Ways of calculating actual, 159.
+
+Glycerol determination, Acetin process, 155.
+
+Glycerol determination, Bichromate process for, 160.
+
+Graining soap, 30.
+
+Grease, 21.
+
+Grease, Bleaching, 21.
+
+Grinding soap, 34.
+
+
+H
+
+Hand Paste, 93.
+
+Hard water, 29.
+
+Hardened oils in toilet soap, Use of, 96.
+
+Hydrocarbon oils, 2.
+
+Hydrogenating oils, 19.
+
+Hydrolysis of fats and oils, 17.
+
+Hydrolytic dissociation of soap, 1.
+
+Hydrometers, 25.
+
+
+I
+
+Indicators, Action, 135-6.
+
+Insoluble impurities in fatty oils, Determination of (standard method), 172.
+  Note on method, 187.
+
+Insoluble matter in soap, determination of, 143.
+
+International committee on glycerine analysis, 150.
+
+Iodine manufacturing oil, 191.
+
+Iodine member Wijs method, Standard, 177-181.
+  Note on method, 191.
+
+Iodine soap, 78.
+
+
+J
+
+Joslin, ref., 113.
+
+
+K
+
+"Killing" change, 36.
+
+Koettstorfer number (Standard method), 181-182.
+
+Kontakt reagent, 117.
+
+Krebitz Process, 123.
+
+Krutolin, 96.
+
+
+L
+
+Leiste & Stiepel method for rosin in soap, 146.
+
+Liebermann, Storch reaction, 144.
+
+Light powders, 60.
+
+Laundry soap, 48.
+
+LeBlanc Process, 28.
+
+Lewkowitsch, ref., 17, 146.
+
+Lime saponification, 118.
+
+Lime, Use in Krebitz Process, 123.
+
+Lime, Use in treatment of glycerine water, 116.
+
+Liquid medicinal soaps, 79.
+
+Liquid soaps, 94.
+
+Lyes, Spent, 37.
+
+
+M
+
+Magnesia, Use in  autoclave saponification, 120.
+
+Manganese sulfate, Use of as catalyzer in fermentative cleavage of fats, 122.
+
+Marine soaps, 39.
+
+Medicinal soaps, 76.
+
+Medicinal soaps, Less important, 78.
+
+Medicinal soaps, Therapeutic value of, 76.
+
+Melting point of fat or oil, Standard method, 193.
+
+Mercury soaps, 78.
+
+Metallic soaps, 1.
+
+Methyl orange, indicator, 136.
+
+Meyerheim, ref., 21.
+
+Mill soap, 32.
+
+Moisture in soap, Determination of, 138, 130.
+
+Moisture and volatile matter in fats and oils, Standard method for
+  detm. of, 170.
+    Note on method, 184-185.
+
+Mottle in soap, 81.
+
+Mug shaving soap, 90.
+
+
+N
+
+Naphtha, Incorporation in soap, 49.
+
+Naphthenic acids, 24.
+
+Nigre, 36.
+
+Normal acids, Equivalent in alkalis, 136.
+
+
+O
+
+Oils and fats, 1.
+
+Oils and fats, Chemical constants, 18.
+
+Oils and fats, Distinction, 1.
+
+Oils and fats, Preserving, 18.
+
+Oils and fat, Nature of used in soap manufacture, 2.
+
+Oils and fats, Rancidity of, 16.
+
+Oil hardening, 19.
+
+Oleic acid, 15, 19.
+
+Olein, 2, 19.
+
+Olive oil, 14.
+
+Olive oil foots, 14.
+
+Organoleptic methods, 127.
+
+
+P
+
+Palmatin, 2.
+
+Palm kernel oil, 8.
+
+Palmitic acid, 2.
+
+Palm oil, 8.
+
+Palm oil, air bleaching, 12.
+
+Palm oil, Chrome bleaching of, 9.
+
+Palm oil soap, 66.
+
+Pearl ash, 29.
+
+Perfuming and coloring toilet soaps, 73.
+
+Peroxide soap, 78.
+
+Petroff reagent, 117.
+
+Pfeilring reagent, 117.
+
+Phenol, 77.
+
+Phenolphthalein, indicator, 38.
+
+Phenolphthalein, Using as indicator, 51.
+
+Phenols, Soaps containing, 77.
+
+Pinic acid, 22.
+
+Plodder, 33.
+
+Potash from wood ash, 27.
+
+Potassium carbonate, 29.
+
+Powders, Light, 60.
+
+Powders, Scouring, 61.
+
+Powders, Shaving, 90.
+
+Powders, Soap, 56.
+
+Precipitation test for treated spent lyes, 110.
+
+Prevention of rancidity, 18.
+
+Pumice or sand soaps, 93.
+
+Purple shade in soap, 75.
+
+
+R
+
+Rancidity of oils and fats, 16.
+
+Rancidity, Prevention, 18.
+
+Recovery of glycerine from spent lye, 106.
+
+Red oil, 15.
+
+Red oil, Saponified, 15.
+
+Resin acids, Total fatty and, Determination of in soap, 144.
+
+Ribot, ref., 20.
+
+Rosin, 22.
+
+Rosin, Determination of in soap, 144.
+
+Rosin saponification, 23.
+
+Run and glued up soaps, 69.
+
+Run soaps, 39.
+
+
+S
+
+Sal soda, 29.
+
+Salt, 30.
+
+Salting out, 30.
+
+Salt "pickle," 37.
+
+Sampling crude glycerine, 162.
+
+Sampling for standard method, 166.
+  Note on, 184.
+
+Sampling oils and fats, 128.
+
+Sampling soap, 137.
+
+Saponification by ferments, 121.
+
+Saponification, Acid, 120.
+
+Saponification, Aqueous, 121.
+
+Saponification, Autoclave, 118.
+
+Saponification, Carbonate, 45.
+
+Saponification defined, 2, 105.
+
+Saponification, Lime, 118.
+
+Saponification number, 181-182.
+
+Saponification, Rosin, 23.
+
+Saponification, Various methods, 105.
+
+Scouring and fulling soaps for wool, 98.
+
+Scouring powders, 61.
+
+Scouring soap, 61.
+
+Semi-boiled laundry soaps, 49.
+
+Semi-boiled process, 44.
+
+Shaving cream, 90.
+
+Shaving powder, 90.
+
+Shaving soaps, 87.
+
+Silica and silicates, Determination of in soap, 148.
+
+Silk dyeing, 102.
+
+Silk industry, Soaps used in, 101.
+
+Slabber, 32.
+
+Smith method for moisture in soap, 138.
+
+Soap analysis, 137.
+
+Soap, Automobile, 41.
+
+Soap, Carbolic, 71.
+
+Soap, Castile, 79.
+
+Soap, Chip, 54.
+
+Soap Chip, cold made, 55.
+
+Soap, Chip, unfilled, 56.
+
+Soap, Cold cream, 78.
+
+Soap, Coloring, 75.
+
+Soap containing phenols, 77.
+
+Soap, Curd, 71.
+
+Soap, Defined, 1.
+
+Soap, Determination insoluble matter, 143.
+
+Soap, Determining glycerine in, 149.
+
+Soap, Eschweger, 81.
+
+Soap, Floating, 62.
+
+Soap, Formaldehyde, 78.
+
+Soap for wool, Scouring and fulling, 98.
+
+Soap, Full boiled, 35.
+
+Soap, Iodine, 78.
+
+Soap kettle, 31.
+
+Soap, Laundry, 48.
+
+Soap, Liquid, 94.
+
+Soap lye crude glycerine, 113.
+
+Soap, Marine, 39.
+
+Soap, Medicinal, 76.
+
+Soap, Medicinal, less important, 78.
+
+Soap, Mercury, 78.
+
+Soap, Metallic, 1.
+
+Soap, Peroxide, 78.
+
+Soap powders, 56.
+
+Soap, Pumice or sand, 93.
+
+Soap, Rosin settled, 50.
+
+Soap, Run and glued up, 69.
+
+Soap, Scouring, 61.
+
+Soap, Semi-boiled laundry, 49.
+
+Soap, Shaving, 87.
+
+Soap, Sulphur, 77.
+
+Soap, Tannin, 78.
+
+Soap, Tar, 77.
+
+Soap, Test for color of, 133.
+
+Soap, Textile, 98.
+
+Soap, Toilet, 65.
+
+Soap, Toilet cheaper, 68.
+
+Soap, Toilet, cold made, 72.
+
+Soap, Toilet perfuming and coloring, 73.
+
+Soap, Transparent, 82.
+
+Soap, Transparent, cold made, 84.
+
+Soap used for cotton goods, 103.
+
+Soap used in the silk industry, 101.
+
+Soap, Witch hazel, 78.
+
+Soap, Wool thrower's, 100.
+
+Soap, Worsted finishing, 101.
+
+Soda ash, 28.
+
+Sodium carbonate, 28.
+
+Sodium perborate, Use of in soap powders, 57.
+
+Soft soaps, 40.
+
+Soluble mineral matter detm. of in fats and oils, 173.
+  Note on method, 187-188.
+
+Solvay process, 28.
+
+Soya bean oil, 14.
+
+Spent lye, Recovery of glycerine from, 106.
+
+Spent lyes, 37.
+
+Spent lyes, Treatment of for glycerine recovery, 107.
+
+Splitting fats with ferments, 121.
+
+Standard methods of analysis for fats and oils, 165-196.
+
+Starch and gelatine, Determination in soap, 143.
+
+Stearic acid, 15, 19.
+
+Stearin, 2, 19.
+
+Strengthening change, 36.
+
+Strengthening lyes, 38.
+
+Strunz crutcher, 63.
+
+Sugar in soap, Determination of, 150.
+
+Sugar, Use in transparent soap, 83.
+
+Sulfate of alumina, Use of in spent lyes, 108.
+
+Sulphonated oils, 104.
+
+Sulphur soaps, 77.
+
+Sweating of soap, 62.
+
+Sweet water, 119.
+
+Sylvic acid, 22.
+
+
+T
+
+Talgol, 96.
+
+Tallow, 4.
+
+Tallow, Fullers' earth bleaching of, 4.
+
+Tallow, Improving color by extraction of free fatty acid, 6.
+
+Tannin soap, 78.
+
+Tar soap, 77.
+
+Test for color of soap, 133.
+
+Testing of alkalis used in soap making, 134.
+
+Textile soaps, 98.
+
+Titer, 130.
+
+Tank cars, Sampling, 166.
+
+Tierces, Sampling, 168.
+
+Titer, Standard method, 175.
+
+Titer, Note on, 189.
+
+Tung oil, Note one iodine, number of, 180.
+
+Toilet soap, 65.
+
+Toilet soaps, Cheaper, 68.
+
+Toilet soap, Use of hardened oils in, 96.
+
+Total alkali, Determination of in soap, 147.
+
+Total fatty and resin acids, Determination of in soap, 144.
+
+Train oils, 20.
+
+Transparent soap, 82.
+
+Transparent soap, Cold made, 84.
+
+Troweling soap, 52.
+
+Tsujimoto, ref., 20.
+
+Tubes for transparent soap, 85.
+
+Turkey red oil, 104.
+
+Twaddle scale, 25.
+
+Twitchell method for rosin, 145.
+
+Twitchell process, 113.
+
+Twitchell process, Advantages, 113.
+
+
+U
+
+Unsaponifiable matter, Determination of in oils and fats, 132.
+
+Unsaponifiable matter, Determination of in soap, 148.
+
+Unsaponifiable matter, determination of by standard method, 176.
+
+
+V
+
+Vacuum Oven, Standard, 176.
+
+Vegetable oils, 6.
+
+
+W
+
+Water, 29.
+
+Water, Hard, 29.
+
+Witch hazel soap, 78.
+
+Wool thrower's soap, 100.
+
+Worsted finishing soaps, 101.
+
+
+Z
+
+Zinc oxide, Use of in autoclave saponification, 120.
+
+Zinc oxide, Use of in soap, 33.
+
+
+
+
+LITERATURE OF THE CHEMICAL INDUSTRIES
+
+
+On our shelves is the most complete stock of technical, industrial,
+engineering and scientific books in the United States. The technical
+literature of every trade is well represented, as is also the literature
+relating to the various sciences, both the books useful for reference as
+well as those fitted for students' use as textbooks.
+
+A large number of these we publish and for an ever increasing number we
+are the sole agents.
+
+ALL INQUIRIES MADE OF US ARE CHEERFULLY AND CAREFULLY ANSWERED AND
+COMPLETE CATALOGS AS WELL AS SPECIAL LISTS SENT FREE ON REQUEST
+
+D. VAN NOSTRAND COMPANY
+
+_Publishers and Booksellers_
+
+8 WARREN STREET NEW YORK
+
+
+The Soap-Maker's Book Shelf
+
+A list of standard books relating to soapmaking and allied industries.
+
+Published and For Sale by
+
+D. VAN NOSTRAND COMPANY
+
+_Publishers and Booksellers_
+
+8 WARREN STREET          NEW YORK
+
+
+~Askinson, George W.~ Perfumes and Cosmetics. Their preparation and
+manufacture. Fourth Edition, translated from the German, and revised
+with additions by W. L. Dudley. 32 illustrations. 6-1/4 × 9-1/2. Cloth.
+354 pp. New York, 1915. ~$5.00~
+
+~Chalmers, T. W.~ The Production and Treatment of Vegetable Oils.
+Including chapters on the refining of oils, the hydrogenation of oils,
+the generation of hydrogen, soap making, the recovery and refining of
+glycerine, and the splitting of oils. 95 illustrations, 9 folding
+plates. 8 × 11-1/2. Cloth. 163 pp. London, 1919. ~$7.50~
+
+~Deite, C.~ Manual of Toilet Soap-Making. Comprising toilet soaps,
+medicated soaps, and other specialties. Second Revised Edition. 85
+illustrations. 6-1/2 × 10. Cloth. 356 pp. London, 1920. ~$7.50~
+
+~Ellis, Carleton G.~ The Hydrogenation of Oils, Catalyzers and Catalysis
+and the Generation of Hydrogen and Oxygen. Second Edition, thoroughly
+revised and enlarged. 240 illustrations. 6-1/4 × 9-1/2. Cloth. 767 pp.
+N. Y., 1919. ~$7.50~
+
+~Fischer, M. H.~ Soaps and Proteins, Their Colloid Chemistry in Theory and
+Practice. With the collaboration of G. D. McLaughlin and M. O. Hooker.
+114 illustrations. 6 × 9-1/4. Cloth. 281 pp. New York, 1921. ~$4.00~
+
+~Holde, D.~ The Examination of Hydrocarbon Oils, and of the Saponifiable
+Fats and Waxes. Translated from the Fourth German Edition by Edward
+Mueller. 115 illustrations. 6-1/4 × 9-1/4. Cloth. 499 pp. N. Y., 1915.
+~Net, $5.00~
+
+~Hurst, G. H~. Soaps. A practical manual of the manufacture of domestic,
+toilet and other soaps. Second Edition. 66 illustrations. 6 × 8-3/4.
+Cloth. 385 pp. London, 1907. ~$6.00~
+
+~Hurst, George H., and Simmons, W. H.~ Textile Soaps and Oils. A handbook
+on the preparation, properties, and analysis of the soaps and oils and
+in textile manufacturing, dyeing and printing. Third Edition, revised.
+12 illustrations. 5-1/2 × 8-3/4. Cloth. 212 pp. London, 1921. ~$4.00~
+
+~Koller, T. Cosmetics.~ A handbook of the manufacture, employment, and
+testing of all cosmetic materials and cosmetic specialties, with
+numerous recipes. Translated from the German. Third Edition. 5 × 7-1/2.
+Cloth. 264 pp. London, 1920. ~$3.50~
+
+~Koppe, S. W. Glycerine.~ Its introduction, Uses and Examination. For
+chemists, perfumers, soapmakers, pharmacists, and explosives
+technologists. 7 illustrations. 5-1/4 × 7-1/2. Cloth. 260 pp. New York,
+1915. ~$3.50~
+
+~Lamborn, L. L.~ Modern Soaps, Candles, and Glycerin. A practical manual
+of modern methods of utilization of fats and oils in the manufacture of
+soaps and candles, and the recovery of glycerin. 228 illustrations.
+6-1/2 × 9-1/4. Cloth. 708 pp. N. Y., 1906. ~$10.00~
+
+~Murray, B. L.~ Standards and Tests for Reagent Chemicals. 6 × 9. Cloth.
+400 pp. New York, 1920. ~$3.00~
+
+~Parry, Ernest J.~ The Chemistry of Essential Oils and Artificial
+Perfumes. Vol. I, Monographs on Essential Oils. Fourth Edition, revised
+and enlarged. 51 illustrations. 6-1/4 × 10. Cloth. 557 pp. London, 1921.
+~$9.00~
+
+Vol. II. Constituents of Essential Oils, Synthetic Perfumes and Isolated
+Aromatics, and the Analysis of Essential Oils. Third Edition, revised
+and enlarged. Illustrated. 351 pp. London, 1919. ~$7.00~
+
+~Partington, J. R.~ The Alkali Industry. 63 illustrations. 5-1/2 × 8-1/2.
+Cloth. 318 pp. London, 1918. ~$3.00~
+
+~Rogers, Allen.~ Industrial Chemistry. A manual for the student and
+manufacturer. Third Edition, thoroughly revised and enlarged. 377
+illustrations. 6-1/2 × 9-3/4. Flexible fabrikoid. 1255 pp. New York,
+1920. ~$7.50~
+
+~Scott, Wilfred W.~ (Editor). Standard Methods of Chemical Analysis. A
+manual of analytical methods and general reference for the analytical
+chemist and for the advanced student. Second Edition, revised, with
+additional tables. 142 illustrations, 3 color plates. 7 × 9-1/4. Cloth.
+900 pp. N. Y., 1917. ~$7.50~
+
+~Simmons, W. H.~ Fats, Waxes and Essential Oils. ~In Press.~
+
+~Simmons, William H.~ Soap. Its composition, manufacture and properties.
+11 illustrations. 4-3/4 × 7-1/4. Cloth. 133 pp. London, 1916. ~$1.00~
+
+~Simmons, W. H., and Appleton, H. A.~ The Handbook of Soap Manufacture. 27
+illustrations. 6 × 9. Cloth. 166 pp. London, 1908. ~$4.00~
+
+~Van Nostrand's Chemical Annual.~ Edited by John C. Olsen. A handbook of
+useful data for analytical manufacturing and investigating chemists and
+chemical students. Fourth Issue, enlarged. 5 × 7-1/2. Flexible
+fabrikoid. 785 pp. New York, 1918. ~$3.00~
+
+~Watt, A.~ Art of Soapmaking. A practical handbook of the manufacture of
+hard and soft soaps, toilet soaps, etc. Seventh Edition, revised and
+enlarged. 43 illustrations. 5-1/4 × 7-1/2. Cloth. 323 pp. London, 1918.
+~$4.00~
+
+~Wright, C. R. A.~ Animal and Vegetable Fixed Oils, Fats, Butters, and
+Waxes: Their Preparation and Properties, and the Manufacture Therefrom
+of Candles, Soaps, and Other Products. Third Edition, revised and
+greatly enlarged by C. Ainsworth Mitchell. 185 illustrations, 3 plates.
+6 × 9. Cloth. 953 pp. London, 1921. ~$16.50~
+
+
+
+
+
+
+End of the Project Gutenberg EBook of Soap-Making Manual, by E. G. Thomssen
+
+*** END OF THIS PROJECT GUTENBERG EBOOK SOAP-MAKING MANUAL ***
+
+***** This file should be named 34114-8.txt or 34114-8.zip *****
+This and all associated files of various formats will be found in:
+        https://www.gutenberg.org/3/4/1/1/34114/
+
+Produced by David Clarke, Josephine Paolucci and the Online
+Distributed Proofreading Team at https://www.pgdp.net. (This
+file was produced from images generously made available
+by The Internet Archive/American Libraries.)
+
+
+Updated editions will replace the previous one--the old editions
+will be renamed.
+
+Creating the works from public domain print editions means that no
+one owns a United States copyright in these works, so the Foundation
+(and you!) can copy and distribute it in the United States without
+permission and without paying copyright royalties.  Special rules,
+set forth in the General Terms of Use part of this license, apply to
+copying and distributing Project Gutenberg-tm electronic works to
+protect the PROJECT GUTENBERG-tm concept and trademark.  Project
+Gutenberg is a registered trademark, and may not be used if you
+charge for the eBooks, unless you receive specific permission.  If you
+do not charge anything for copies of this eBook, complying with the
+rules is very easy.  You may use this eBook for nearly any purpose
+such as creation of derivative works, reports, performances and
+research.  They may be modified and printed and given away--you may do
+practically ANYTHING with public domain eBooks.  Redistribution is
+subject to the trademark license, especially commercial
+redistribution.
+
+
+
+*** START: FULL LICENSE ***
+
+THE FULL PROJECT GUTENBERG LICENSE
+PLEASE READ THIS BEFORE YOU DISTRIBUTE OR USE THIS WORK
+
+To protect the Project Gutenberg-tm mission of promoting the free
+distribution of electronic works, by using or distributing this work
+(or any other work associated in any way with the phrase "Project
+Gutenberg"), you agree to comply with all the terms of the Full Project
+Gutenberg-tm License (available with this file or online at
+https://gutenberg.org/license).
+
+
+Section 1.  General Terms of Use and Redistributing Project Gutenberg-tm
+electronic works
+
+1.A.  By reading or using any part of this Project Gutenberg-tm
+electronic work, you indicate that you have read, understand, agree to
+and accept all the terms of this license and intellectual property
+(trademark/copyright) agreement.  If you do not agree to abide by all
+the terms of this agreement, you must cease using and return or destroy
+all copies of Project Gutenberg-tm electronic works in your possession.
+If you paid a fee for obtaining a copy of or access to a Project
+Gutenberg-tm electronic work and you do not agree to be bound by the
+terms of this agreement, you may obtain a refund from the person or
+entity to whom you paid the fee as set forth in paragraph 1.E.8.
+
+1.B.  "Project Gutenberg" is a registered trademark.  It may only be
+used on or associated in any way with an electronic work by people who
+agree to be bound by the terms of this agreement.  There are a few
+things that you can do with most Project Gutenberg-tm electronic works
+even without complying with the full terms of this agreement.  See
+paragraph 1.C below.  There are a lot of things you can do with Project
+Gutenberg-tm electronic works if you follow the terms of this agreement
+and help preserve free future access to Project Gutenberg-tm electronic
+works.  See paragraph 1.E below.
+
+1.C.  The Project Gutenberg Literary Archive Foundation ("the Foundation"
+or PGLAF), owns a compilation copyright in the collection of Project
+Gutenberg-tm electronic works.  Nearly all the individual works in the
+collection are in the public domain in the United States.  If an
+individual work is in the public domain in the United States and you are
+located in the United States, we do not claim a right to prevent you from
+copying, distributing, performing, displaying or creating derivative
+works based on the work as long as all references to Project Gutenberg
+are removed.  Of course, we hope that you will support the Project
+Gutenberg-tm mission of promoting free access to electronic works by
+freely sharing Project Gutenberg-tm works in compliance with the terms of
+this agreement for keeping the Project Gutenberg-tm name associated with
+the work.  You can easily comply with the terms of this agreement by
+keeping this work in the same format with its attached full Project
+Gutenberg-tm License when you share it without charge with others.
+
+1.D.  The copyright laws of the place where you are located also govern
+what you can do with this work.  Copyright laws in most countries are in
+a constant state of change.  If you are outside the United States, check
+the laws of your country in addition to the terms of this agreement
+before downloading, copying, displaying, performing, distributing or
+creating derivative works based on this work or any other Project
+Gutenberg-tm work.  The Foundation makes no representations concerning
+the copyright status of any work in any country outside the United
+States.
+
+1.E.  Unless you have removed all references to Project Gutenberg:
+
+1.E.1.  The following sentence, with active links to, or other immediate
+access to, the full Project Gutenberg-tm License must appear prominently
+whenever any copy of a Project Gutenberg-tm work (any work on which the
+phrase "Project Gutenberg" appears, or with which the phrase "Project
+Gutenberg" is associated) is accessed, displayed, performed, viewed,
+copied or distributed:
+
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever.  You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at www.gutenberg.org
+
+1.E.2.  If an individual Project Gutenberg-tm electronic work is derived
+from the public domain (does not contain a notice indicating that it is
+posted with permission of the copyright holder), the work can be copied
+and distributed to anyone in the United States without paying any fees
+or charges.  If you are redistributing or providing access to a work
+with the phrase "Project Gutenberg" associated with or appearing on the
+work, you must comply either with the requirements of paragraphs 1.E.1
+through 1.E.7 or obtain permission for the use of the work and the
+Project Gutenberg-tm trademark as set forth in paragraphs 1.E.8 or
+1.E.9.
+
+1.E.3.  If an individual Project Gutenberg-tm electronic work is posted
+with the permission of the copyright holder, your use and distribution
+must comply with both paragraphs 1.E.1 through 1.E.7 and any additional
+terms imposed by the copyright holder.  Additional terms will be linked
+to the Project Gutenberg-tm License for all works posted with the
+permission of the copyright holder found at the beginning of this work.
+
+1.E.4.  Do not unlink or detach or remove the full Project Gutenberg-tm
+License terms from this work, or any files containing a part of this
+work or any other work associated with Project Gutenberg-tm.
+
+1.E.5.  Do not copy, display, perform, distribute or redistribute this
+electronic work, or any part of this electronic work, without
+prominently displaying the sentence set forth in paragraph 1.E.1 with
+active links or immediate access to the full terms of the Project
+Gutenberg-tm License.
+
+1.E.6.  You may convert to and distribute this work in any binary,
+compressed, marked up, nonproprietary or proprietary form, including any
+word processing or hypertext form.  However, if you provide access to or
+distribute copies of a Project Gutenberg-tm work in a format other than
+"Plain Vanilla ASCII" or other format used in the official version
+posted on the official Project Gutenberg-tm web site (www.gutenberg.org),
+you must, at no additional cost, fee or expense to the user, provide a
+copy, a means of exporting a copy, or a means of obtaining a copy upon
+request, of the work in its original "Plain Vanilla ASCII" or other
+form.  Any alternate format must include the full Project Gutenberg-tm
+License as specified in paragraph 1.E.1.
+
+1.E.7.  Do not charge a fee for access to, viewing, displaying,
+performing, copying or distributing any Project Gutenberg-tm works
+unless you comply with paragraph 1.E.8 or 1.E.9.
+
+1.E.8.  You may charge a reasonable fee for copies of or providing
+access to or distributing Project Gutenberg-tm electronic works provided
+that
+
+- You pay a royalty fee of 20% of the gross profits you derive from
+     the use of Project Gutenberg-tm works calculated using the method
+     you already use to calculate your applicable taxes.  The fee is
+     owed to the owner of the Project Gutenberg-tm trademark, but he
+     has agreed to donate royalties under this paragraph to the
+     Project Gutenberg Literary Archive Foundation.  Royalty payments
+     must be paid within 60 days following each date on which you
+     prepare (or are legally required to prepare) your periodic tax
+     returns.  Royalty payments should be clearly marked as such and
+     sent to the Project Gutenberg Literary Archive Foundation at the
+     address specified in Section 4, "Information about donations to
+     the Project Gutenberg Literary Archive Foundation."
+
+- You provide a full refund of any money paid by a user who notifies
+     you in writing (or by e-mail) within 30 days of receipt that s/he
+     does not agree to the terms of the full Project Gutenberg-tm
+     License.  You must require such a user to return or
+     destroy all copies of the works possessed in a physical medium
+     and discontinue all use of and all access to other copies of
+     Project Gutenberg-tm works.
+
+- You provide, in accordance with paragraph 1.F.3, a full refund of any
+     money paid for a work or a replacement copy, if a defect in the
+     electronic work is discovered and reported to you within 90 days
+     of receipt of the work.
+
+- You comply with all other terms of this agreement for free
+     distribution of Project Gutenberg-tm works.
+
+1.E.9.  If you wish to charge a fee or distribute a Project Gutenberg-tm
+electronic work or group of works on different terms than are set
+forth in this agreement, you must obtain permission in writing from
+both the Project Gutenberg Literary Archive Foundation and Michael
+Hart, the owner of the Project Gutenberg-tm trademark.  Contact the
+Foundation as set forth in Section 3 below.
+
+1.F.
+
+1.F.1.  Project Gutenberg volunteers and employees expend considerable
+effort to identify, do copyright research on, transcribe and proofread
+public domain works in creating the Project Gutenberg-tm
+collection.  Despite these efforts, Project Gutenberg-tm electronic
+works, and the medium on which they may be stored, may contain
+"Defects," such as, but not limited to, incomplete, inaccurate or
+corrupt data, transcription errors, a copyright or other intellectual
+property infringement, a defective or damaged disk or other medium, a
+computer virus, or computer codes that damage or cannot be read by
+your equipment.
+
+1.F.2.  LIMITED WARRANTY, DISCLAIMER OF DAMAGES - Except for the "Right
+of Replacement or Refund" described in paragraph 1.F.3, the Project
+Gutenberg Literary Archive Foundation, the owner of the Project
+Gutenberg-tm trademark, and any other party distributing a Project
+Gutenberg-tm electronic work under this agreement, disclaim all
+liability to you for damages, costs and expenses, including legal
+fees.  YOU AGREE THAT YOU HAVE NO REMEDIES FOR NEGLIGENCE, STRICT
+LIABILITY, BREACH OF WARRANTY OR BREACH OF CONTRACT EXCEPT THOSE
+PROVIDED IN PARAGRAPH 1.F.3.  YOU AGREE THAT THE FOUNDATION, THE
+TRADEMARK OWNER, AND ANY DISTRIBUTOR UNDER THIS AGREEMENT WILL NOT BE
+LIABLE TO YOU FOR ACTUAL, DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE OR
+INCIDENTAL DAMAGES EVEN IF YOU GIVE NOTICE OF THE POSSIBILITY OF SUCH
+DAMAGE.
+
+1.F.3.  LIMITED RIGHT OF REPLACEMENT OR REFUND - If you discover a
+defect in this electronic work within 90 days of receiving it, you can
+receive a refund of the money (if any) you paid for it by sending a
+written explanation to the person you received the work from.  If you
+received the work on a physical medium, you must return the medium with
+your written explanation.  The person or entity that provided you with
+the defective work may elect to provide a replacement copy in lieu of a
+refund.  If you received the work electronically, the person or entity
+providing it to you may choose to give you a second opportunity to
+receive the work electronically in lieu of a refund.  If the second copy
+is also defective, you may demand a refund in writing without further
+opportunities to fix the problem.
+
+1.F.4.  Except for the limited right of replacement or refund set forth
+in paragraph 1.F.3, this work is provided to you 'AS-IS' WITH NO OTHER
+WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
+WARRANTIES OF MERCHANTIBILITY OR FITNESS FOR ANY PURPOSE.
+
+1.F.5.  Some states do not allow disclaimers of certain implied
+warranties or the exclusion or limitation of certain types of damages.
+If any disclaimer or limitation set forth in this agreement violates the
+law of the state applicable to this agreement, the agreement shall be
+interpreted to make the maximum disclaimer or limitation permitted by
+the applicable state law.  The invalidity or unenforceability of any
+provision of this agreement shall not void the remaining provisions.
+
+1.F.6.  INDEMNITY - You agree to indemnify and hold the Foundation, the
+trademark owner, any agent or employee of the Foundation, anyone
+providing copies of Project Gutenberg-tm electronic works in accordance
+with this agreement, and any volunteers associated with the production,
+promotion and distribution of Project Gutenberg-tm electronic works,
+harmless from all liability, costs and expenses, including legal fees,
+that arise directly or indirectly from any of the following which you do
+or cause to occur: (a) distribution of this or any Project Gutenberg-tm
+work, (b) alteration, modification, or additions or deletions to any
+Project Gutenberg-tm work, and (c) any Defect you cause.
+
+
+Section  2.  Information about the Mission of Project Gutenberg-tm
+
+Project Gutenberg-tm is synonymous with the free distribution of
+electronic works in formats readable by the widest variety of computers
+including obsolete, old, middle-aged and new computers.  It exists
+because of the efforts of hundreds of volunteers and donations from
+people in all walks of life.
+
+Volunteers and financial support to provide volunteers with the
+assistance they need are critical to reaching Project Gutenberg-tm's
+goals and ensuring that the Project Gutenberg-tm collection will
+remain freely available for generations to come.  In 2001, the Project
+Gutenberg Literary Archive Foundation was created to provide a secure
+and permanent future for Project Gutenberg-tm and future generations.
+To learn more about the Project Gutenberg Literary Archive Foundation
+and how your efforts and donations can help, see Sections 3 and 4
+and the Foundation web page at https://www.pglaf.org.
+
+
+Section 3.  Information about the Project Gutenberg Literary Archive
+Foundation
+
+The Project Gutenberg Literary Archive Foundation is a non profit
+501(c)(3) educational corporation organized under the laws of the
+state of Mississippi and granted tax exempt status by the Internal
+Revenue Service.  The Foundation's EIN or federal tax identification
+number is 64-6221541.  Its 501(c)(3) letter is posted at
+https://pglaf.org/fundraising.  Contributions to the Project Gutenberg
+Literary Archive Foundation are tax deductible to the full extent
+permitted by U.S. federal laws and your state's laws.
+
+The Foundation's principal office is located at 4557 Melan Dr. S.
+Fairbanks, AK, 99712., but its volunteers and employees are scattered
+throughout numerous locations.  Its business office is located at
+809 North 1500 West, Salt Lake City, UT 84116, (801) 596-1887, email
+business@pglaf.org.  Email contact links and up to date contact
+information can be found at the Foundation's web site and official
+page at https://pglaf.org
+
+For additional contact information:
+     Dr. Gregory B. Newby
+     Chief Executive and Director
+     gbnewby@pglaf.org
+
+
+Section 4.  Information about Donations to the Project Gutenberg
+Literary Archive Foundation
+
+Project Gutenberg-tm depends upon and cannot survive without wide
+spread public support and donations to carry out its mission of
+increasing the number of public domain and licensed works that can be
+freely distributed in machine readable form accessible by the widest
+array of equipment including outdated equipment.  Many small donations
+($1 to $5,000) are particularly important to maintaining tax exempt
+status with the IRS.
+
+The Foundation is committed to complying with the laws regulating
+charities and charitable donations in all 50 states of the United
+States.  Compliance requirements are not uniform and it takes a
+considerable effort, much paperwork and many fees to meet and keep up
+with these requirements.  We do not solicit donations in locations
+where we have not received written confirmation of compliance.  To
+SEND DONATIONS or determine the status of compliance for any
+particular state visit https://pglaf.org
+
+While we cannot and do not solicit contributions from states where we
+have not met the solicitation requirements, we know of no prohibition
+against accepting unsolicited donations from donors in such states who
+approach us with offers to donate.
+
+International donations are gratefully accepted, but we cannot make
+any statements concerning tax treatment of donations received from
+outside the United States.  U.S. laws alone swamp our small staff.
+
+Please check the Project Gutenberg Web pages for current donation
+methods and addresses.  Donations are accepted in a number of other
+ways including including checks, online payments and credit card
+donations.  To donate, please visit: https://pglaf.org/donate
+
+
+Section 5.  General Information About Project Gutenberg-tm electronic
+works.
+
+Professor Michael S. Hart was the originator of the Project Gutenberg-tm
+concept of a library of electronic works that could be freely shared
+with anyone.  For thirty years, he produced and distributed Project
+Gutenberg-tm eBooks with only a loose network of volunteer support.
+
+
+Project Gutenberg-tm eBooks are often created from several printed
+editions, all of which are confirmed as Public Domain in the U.S.
+unless a copyright notice is included.  Thus, we do not necessarily
+keep eBooks in compliance with any particular paper edition.
+
+
+Most people start at our Web site which has the main PG search facility:
+
+     https://www.gutenberg.org
+
+This Web site includes information about Project Gutenberg-tm,
+including how to make donations to the Project Gutenberg Literary
+Archive Foundation, how to help produce our new eBooks, and how to
+subscribe to our email newsletter to hear about new eBooks.
diff --git a/34114-8.zip b/34114-8.zip
new file mode 100644
index 0000000..1ec0fe9
--- /dev/null
+++ b/34114-8.zip
diff --git a/34114-h.zip b/34114-h.zip
new file mode 100644
index 0000000..849ac97
--- /dev/null
+++ b/34114-h.zip
diff --git a/34114-h/34114-h.htm b/34114-h/34114-h.htm
new file mode 100644
index 0000000..9168f65
--- /dev/null
+++ b/34114-h/34114-h.htm
@@ -0,0 +1,9631 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
+    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
+
+<html xmlns="http://www.w3.org/1999/xhtml">
+  <head>
+    <meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1" />
+    <title>
+      The Project Gutenberg eBook of Soap-making Manual, by E. G. Thomssen, Ph. D.
+    </title>
+    <style type="text/css">
+
+    p {  margin-top: .75em;
+         text-align: justify;
+         margin-bottom: .75em;
+         }
+    h1,h2,h3,h4,h5,h6 {
+         text-align: center; /* all headings centered */
+         clear: both;
+         }
+    hr { width: 33%;
+	 margin-top: 2em;
+	 margin-bottom: 2em;
+         margin-left: auto;
+         margin-right: auto;
+         clear: both;
+       }
+
+    table {margin-left: auto; margin-right: auto;}
+
+    body{margin-left: 10%;
+         margin-right: 10%;
+        }
+
+    .pagenum  { /* uncomment the next line for invisible page numbers */
+            /*  visibility: hidden;  */
+                position: absolute;
+                left: 92%;
+                font-size: smaller;
+                text-align: right;
+              } /* page numbers */
+
+    .notes    {background-color: #eeeeee; color: #000; padding: .5em; margin-left: 10%; margin-right: 10%;}
+    .tocnum  {position: absolute; top: auto; right: 15%;}
+    .blockquot{margin-left: 5%; margin-right: 10%;}
+
+    .bbox     {border: solid 2px;}
+
+    .center   {text-align: center;}
+    .smcap    {font-variant: small-caps;}
+    .right    {text-align: right;}
+
+    .caption  {font-weight: bold;}
+
+    .figcenter   {margin: auto; text-align: center;}
+
+    .figleft     {float: left; clear: left; margin-left: 0; margin-bottom: 1em; margin-top:
+                 1em; margin-right: 1em; padding: 0; text-align: center;}
+
+    .figright    {float: right; clear: right; margin-left: 1em; margin-bottom: 1em;
+                 margin-top: 1em; margin-right: 0; padding: 0; text-align: center;}
+
+    .footnotes        {border: dashed 1px;}
+    .footnote         {margin-left: 10%; margin-right: 10%; font-size: 0.9em;}
+    .footnote .label  {position: absolute; right: 84%; text-align: right;}
+    .fnanchor         {vertical-align: super; font-size: .8em; text-decoration: none;}
+
+    .poem             {margin-left:10%; margin-right:10%; text-align: left;}
+    .poem br          {display: none;}
+    .poem .stanza     {margin: 1em 0em 1em 0em;}
+    .poem span.i0     {display: block; margin-left: 0em; padding-left: 3em; text-indent: -3em;}
+    .poem span.i2     {display: block; margin-left: 1em; padding-left: 3em; text-indent: -3em;}
+    .poem span.i4     {display: block; margin-left: 2em; padding-left: 3em; text-indent: -3em;}
+
+    </style>
+  </head>
+<body>
+
+
+<pre>
+
+The Project Gutenberg EBook of Soap-Making Manual, by E. G. Thomssen
+
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever.  You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at www.gutenberg.org
+
+
+Title: Soap-Making Manual
+       A Practical Handbook on the Raw Materials, Their
+              Manipulation, Analysis and Control in the Modern Soap Plant.
+
+Author: E. G. Thomssen
+
+Release Date: October 22, 2010 [EBook #34114]
+
+Language: English
+
+Character set encoding: ISO-8859-1
+
+*** START OF THIS PROJECT GUTENBERG EBOOK SOAP-MAKING MANUAL ***
+
+
+
+
+Produced by David Clarke, Josephine Paolucci and the Online
+Distributed Proofreading Team at https://www.pgdp.net. (This
+file was produced from images generously made available
+by The Internet Archive/American Libraries.)
+
+
+
+
+
+
+</pre>
+
+
+
+<h1>Soap-Making Manual</h1>
+
+<h3>A practical handbook on the raw materials, their manipulation, analysis
+and control in the modern soap plant.</h3>
+
+<h3>By</h3>
+
+<h2><i>E. G. Thomssen, Ph. D.</i></h2>
+
+<h4>ILLUSTRATED</h4>
+
+<div class="figcenter" style="width: 150px;">
+<img src="images/title.jpg" width="150" height="130" alt="" title="" />
+</div>
+
+<p class="center">
+NEW YORK<br />
+<br />
+D. VAN NOSTRAND COMPANY<br />
+<br />
+<span class="smcap">Eight Warren Street</span><br />
+<br />
+1922<br />
+<br />
+<span class="smcap">Copyright</span> 1922<br />
+<br />
+<span class="smcap">By</span><br />
+<br />
+D. VAN NOSTRAND COMPANY<br />
+<br />
+Printed in the United States of America<br />
+<span class='pagenum'><a name="Page_iii" id="Page_iii">[Pg iii]</a></span></p>
+
+
+
+<hr style="width: 65%;" />
+<h2>PREFATORY NOTE.</h2>
+
+
+<p>The material contained in this work appeared several years ago in serial
+form in the American Perfumer and Essential Oil Review. Owing to the
+numerous requests received, it has been decided to now place before
+those interested, these articles in book form. While it is true that the
+works pertaining to the soapmaking industry are reasonably plentiful,
+books are quite rare, however, which, in a brief volume, will clearly
+outline the processes employed together with the necessary methods of
+analyses from a purely practical standpoint. In the work presented the
+author has attempted to briefly, clearly, and fully explain the
+manufacture of soap in such language that it might be understood by all
+those interested in this industry. In many cases the smaller plants find
+it necessary to dispense with the services of a chemist, so that it is
+necessary for the soapmaker to make his own tests. The tests outlined,
+therefore, are given as simple as possible to meet this condition. The
+formulae submitted are authentic, and in many cases are now being used
+in soapmaking.</p>
+
+<p>In taking up the industry for survey it has been thought desirable to
+first mention and describe the raw materials used; second, to outline
+the processes of manufacture; third, to classify the methods and
+illustrate by formulae the composition of various soaps together with
+their mode of manufacture; fourth, to enumerate the various methods of
+glycerine recovery, including the processes of saponification, and,
+fifth, to give the most important analytical methods which are of value
+to control<span class='pagenum'><a name="Page_iv" id="Page_iv">[Pg iv]</a></span> the process of manufacture and to determine the purity and
+fitness of the raw material entering into it.</p>
+
+<p>It is not the intention of the author to go into great detail in this
+work, nor to outline to any great extent the theoretical side of the
+subject, but rather to make the work as brief as possible, keeping the
+practical side of the subject before him and not going into concise
+descriptions of machinery as is very usual in works on this subject.
+Illustrations are merely added to show typical kinds of machinery used.</p>
+
+<p>The author wishes to take this opportunity of thanking Messrs. L. S.
+Levy and E. W. Drew for the reading of proof, and Mr. C. W. Aiken of the
+Houchin-Aiken Co., for his aid in making the illustrations a success, as
+well as others who have contributed in the compiling of the formulae for
+various soaps. He trusts that this work may prove of value to those
+engaged in soap manufacture.</p>
+
+<p class="right">
+E. G. T.<br />
+</p>
+
+<p>January, 1922</p>
+
+<hr style="width: 65%;" />
+
+<p class="notes">Transcriber's note: This is a series of articles collected into a book. There are
+differences in spelling and punctuation in the different chapters (e.g.
+cocoanut in one chapter and coconut in another). These differences were
+left in the text as they appeared.</p>
+
+<hr style="width: 65%;" /><p><span class='pagenum'><a name="Page_v" id="Page_v">[Pg v]</a></span></p>
+<h2>TABLE OF CONTENTS.</h2>
+
+<p>
+CHAPTER I.                                                      <span class="tocnum">Page.</span><br />
+<br />
+<span class="smcap">Raw Materials Used in Soap Making</span>                      <span class="tocnum"><a href='#Page_1'>1-30</a></span><br />
+<br />
+<span style="margin-left: 1em;">1. Soap Defined</span>                         <span class="tocnum"><a href='#Page_1'>1</a></span><br />
+<br />
+<span style="margin-left: 1em;">2. Oils and Fats</span>                       <span class="tocnum"><a href='#Page_1'>1-2</a></span><br />
+<br />
+<span style="margin-left: 1em;">3. Saponification Defined</span>                   <span class="tocnum"><a href='#Page_2'>2-3</a></span><br />
+<br />
+<span style="margin-left: 1em;">4. Fats and Oils Used in Soap Manufacture</span>           <span class="tocnum"><a href='#Page_3'>3-4</a></span><br />
+<span style="margin-left: 2em;">Fullers' Earth Process for Bleaching Tallow</span>         <span class="tocnum"><a href='#Page_4'>4-6</a></span><br />
+<span style="margin-left: 2em;">Method for Further Improvement of Color in Tallow</span>       <span class="tocnum"><a href='#Page_6'>6</a></span><br />
+<span style="margin-left: 2em;">Vegetable Oils</span>                       <span class="tocnum"><a href='#Page_6'>6-9</a></span><br />
+<span style="margin-left: 2em;">Chrome Bleaching of Palm Oil</span>                <span class="tocnum"><a href='#Page_9'>9-12</a></span><br />
+<span style="margin-left: 2em;">Air Bleaching of Palm Oil</span>                 <span class="tocnum"><a href='#Page_12'>12-16</a></span><br />
+<br />
+<span style="margin-left: 1em;">5. Rancidity of Oils and Fats</span>                <span class="tocnum"><a href='#Page_16'>16-18</a></span><br />
+<span style="margin-left: 2em;">Prevention of Rancidity</span>                   <span class="tocnum"><a href='#Page_18'>18</a></span><br />
+<br />
+<span style="margin-left: 1em;">6. Chemical Constants of Oils and Fats</span>           <span class="tocnum"><a href='#Page_18'>18-19</a></span><br />
+<br />
+<span style="margin-left: 1em;">7. Oil Hardening or Hydrogenating</span>              <span class="tocnum"><a href='#Page_19'>19-21</a></span><br />
+<br />
+<span style="margin-left: 1em;">8. Grease</span>                          <span class="tocnum"><a href='#Page_21'>21-22</a></span><br />
+<br />
+<span style="margin-left: 1em;">9. Rosin (Colophony, Yellow Rosin, Resina)</span>         <span class="tocnum"><a href='#Page_22'>22-23</a></span><br />
+<br />
+<span style="margin-left: 1em;">10. Rosin Saponification</span>                  <span class="tocnum"><a href='#Page_23'>23-24</a></span><br />
+<br />
+<span style="margin-left: 1em;">11. Naphthenic Acids</span>                    <span class="tocnum"><a href='#Page_24'>24-25</a></span><br />
+<br />
+<span style="margin-left: 1em;">12. Alkalis</span>                         <span class="tocnum"><a href='#Page_25'>25-26</a></span><br />
+<span style="margin-left: 2em;">Caustic Soda</span>                         <span class="tocnum"><a href='#Page_26'>26</a></span><br />
+<span style="margin-left: 2em;">Caustic Potash</span>                      <span class="tocnum"><a href='#Page_26'>26-28</a></span><br />
+<span style="margin-left: 2em;">Sodium Carbonate (Soda Ash)</span>                <span class="tocnum"><a href='#Page_28'>28-29</a></span><br />
+<span style="margin-left: 2em;">Potassium Carbonate</span>                     <span class="tocnum"><a href='#Page_29'>29</a></span><br />
+<br />
+<span style="margin-left: 1em;">13. Additional Material Used in Soap Making</span>         <span class="tocnum"><a href='#Page_29'>29-30</a></span><br />
+<br />
+<br />
+CHAPTER II.<br />
+<br />
+<span class="smcap">Construction and Equipment of a Soap Plant</span>            <span class="tocnum"><a href='#Page_31'>31-34</a></span><br />
+<br />
+<br />
+CHAPTER III.<br />
+<br />
+<span class="smcap">Classification of Soap Making Methods</span>                 <span class="tocnum"><a href='#Page_35'>35-46</a></span><br />
+<br />
+<span style="margin-left: 1em;">1. Full Boiled Soaps</span>                    <span class="tocnum"><a href='#Page_36'>36-42</a></span><br />
+<br />
+<span style="margin-left: 1em;">2. Cold Process</span>                       <span class="tocnum"><a href='#Page_43'>43-44</a></span><br />
+<br />
+<span style="margin-left: 1em;">3. Carbonate Saponification</span>                 <span class="tocnum"><a href='#Page_45'>45-46</a></span><br />
+<br />
+<br />
+CHAPTER IV.<br />
+<br />
+<span class="smcap">Classification of Soaps</span>                              <span class="tocnum"><a href='#Page_47'>47-104</a></span><br />
+<br />
+<span style="margin-left: 1em;">1. Laundry Soap</span>                        <span class="tocnum"><a href='#Page_48'>48</a></span><br />
+<span style="margin-left: 2em;">Semi-Boiled Laundry Soap</span>                 <span class="tocnum"><a href='#Page_49'>49-50</a></span><br />
+<span style="margin-left: 2em;">Settled Rosin Soap</span>                    <span class="tocnum"><a href='#Page_50'>50-54</a></span><br />
+<br />
+<span class='pagenum'><a name="Page_vi" id="Page_vi">[Pg vi]</a></span><span style="margin-left: 1em;">2. Chip Soap</span>                        <span class="tocnum"><a href='#Page_54'>54-55</a></span><br />
+<span style="margin-left: 2em;">Cold Made Chip Soap</span>                    <span class="tocnum"><a href='#Page_55'>55-56</a></span><br />
+<span style="margin-left: 2em;">Unfilled Chip Soap</span>                      <span class="tocnum"><a href='#Page_56'>56</a></span><br />
+<br />
+<span style="margin-left: 1em;">3. Soap Powders </span>                      <span class="tocnum"><a href='#Page_56'>56-59</a></span><br />
+<span style="margin-left: 2em;">Light Powders </span>                      <span class="tocnum"><a href='#Page_60'>60-61</a></span><br />
+<br />
+<span style="margin-left: 1em;">4. Scouring Powders</span>                      <span class="tocnum"><a href='#Page_61'>61</a></span><br />
+<br />
+<span style="margin-left: 1em;">5. Scouring Soap</span>                      <span class="tocnum"><a href='#Page_61'>61-62</a></span><br />
+<br />
+<span style="margin-left: 1em;">6. Floating Soap</span>                      <span class="tocnum"><a href='#Page_62'>62-65</a></span><br />
+<br />
+<span style="margin-left: 1em;">7. Toilet Soap</span>                       <span class="tocnum"><a href='#Page_65'>65-68</a></span><br />
+<span style="margin-left: 2em;">Cheaper Toilet Soaps</span>                   <span class="tocnum"><a href='#Page_68'>68-69</a></span><br />
+<span style="margin-left: 2em;">Run and Glued-up Soaps</span>                  <span class="tocnum"><a href='#Page_69'>69-71</a></span><br />
+<span style="margin-left: 2em;">Curd Soap</span>                         <span class="tocnum"><a href='#Page_71'>71-72</a></span><br />
+<span style="margin-left: 2em;">Cold Made Toilet Soaps</span>                  <span class="tocnum"><a href='#Page_72'>72-73</a></span><br />
+<span style="margin-left: 2em;">Perfuming and Coloring Toilet Soaps</span>            <span class="tocnum"><a href='#Page_73'>73-75</a></span><br />
+<span style="margin-left: 2em;">Coloring Soap</span>                       <span class="tocnum"><a href='#Page_75'>75-76</a></span><br />
+<br />
+<span style="margin-left: 1em;">8. Medicinal Soaps</span>                     <span class="tocnum"><a href='#Page_76'>76-77</a></span><br />
+<span style="margin-left: 2em;">Sulphur Soaps</span>                        <span class="tocnum"><a href='#Page_77'>77</a></span><br />
+<span style="margin-left: 2em;">Tar Soap</span>                           <span class="tocnum"><a href='#Page_77'>77</a></span><br />
+<span style="margin-left: 2em;">Soaps Containing Phenols</span>                 <span class="tocnum"><a href='#Page_77'>77-78</a></span><br />
+<span style="margin-left: 2em;">Peroxide Soap</span>                        <span class="tocnum"><a href='#Page_78'>78</a></span><br />
+<span style="margin-left: 2em;">Mercury Soaps</span>                        <span class="tocnum"><a href='#Page_78'>78</a></span><br />
+<span style="margin-left: 2em;">Less Important Medicinal Soaps</span>              <span class="tocnum"><a href='#Page_78'>78-79</a></span><br />
+<br />
+<span style="margin-left: 1em;">9. Castile Soap</span>                       <span class="tocnum"><a href='#Page_79'>79-81</a></span><br />
+<br />
+<span style="margin-left: 1em;">10. Eschweger Soap</span>                     <span class="tocnum"><a href='#Page_81'>81-82</a></span><br />
+<br />
+<span style="margin-left: 1em;">11. Transparent Soap</span>                    <span class="tocnum"><a href='#Page_82'>82-84</a></span><br />
+<span style="margin-left: 2em;">Cold Made Transparent Soap</span>                <span class="tocnum"><a href='#Page_84'>84-87</a></span><br />
+<br />
+<span style="margin-left: 1em;">12. Shaving Soaps</span>                      <span class="tocnum"><a href='#Page_87'>87-90</a></span><br />
+<span style="margin-left: 2em;">Shaving Powder</span>                        <span class="tocnum"><a href='#Page_90'>90</a></span><br />
+<span style="margin-left: 2em;">Shaving Cream</span>                       <span class="tocnum"><a href='#Page_90'>90-93</a></span><br />
+<br />
+<span style="margin-left: 1em;">13. Pumice or Sand Soaps</span>                  <span class="tocnum"><a href='#Page_93'>93-94</a></span><br />
+<br />
+<span style="margin-left: 1em;">14. Liquid Soaps</span>                      <span class="tocnum"><a href='#Page_94'>94-95</a></span><br />
+<br />
+<span style="margin-left: 1em;">15. Use of Hardened Oils in Toilet Soaps</span>          <span class="tocnum"><a href='#Page_96'>96-98</a></span><br />
+<br />
+<span style="margin-left: 1em;">16. Textile Soaps</span>                       <span class="tocnum"><a href='#Page_98'>98</a></span><br />
+<span style="margin-left: 2em;">Scouring and Fulling Soaps for Wool</span>           <span class="tocnum"><a href='#Page_98'>98-100</a></span><br />
+<span style="margin-left: 2em;">Wool Thrower's Soap</span>                   <span class="tocnum"><a href='#Page_100'>100-101</a></span><br />
+<span style="margin-left: 2em;">Worsted Finishing Soaps</span>                   <span class="tocnum"><a href='#Page_101'>101</a></span><br />
+<span style="margin-left: 2em;">Soaps Used in the Silk Industry</span>             <span class="tocnum"><a href='#Page_101'>101-103</a></span><br />
+<span style="margin-left: 2em;">Soaps Used for Cotton Goods</span>               <span class="tocnum"><a href='#Page_103'>103-104</a></span><br />
+<br />
+<span style="margin-left: 1em;">17. Sulphonated Oils</span>                   <span class="tocnum"><a href='#Page_104'>104-105</a></span><br />
+<br />
+<br />
+CHAPTER V.<br />
+<br />
+<span class="smcap">Glycerine Recovery</span>                                  <span class="tocnum"><a href='#Page_105'>105-126</a></span><br />
+<br />
+<span class='pagenum'><a name="Page_vii" id="Page_vii">[Pg vii]</a></span><span style="margin-left: 1em;">1. Methods of Saponification</span>               <span class="tocnum"><a href='#Page_105'>105-106</a></span><br />
+<span style="margin-left: 2.5em;">Recovery of Glycerine from Spent Lye</span>          <span class="tocnum"><a href='#Page_106'>106-113</a></span><br />
+<span style="margin-left: 2.5em;">Twitchell Process</span>                   <span class="tocnum"><a href='#Page_113'>113-118</a></span><br />
+<span style="margin-left: 2.5em;">Autoclave Saponification</span>                  <span class="tocnum"><a href='#Page_118'>118</a></span><br />
+<span style="margin-left: 2.5em;">Lime Saponification</span>                  <span class="tocnum"><a href='#Page_118'>118-120</a></span><br />
+<span style="margin-left: 2.5em;">Acid Saponification</span>                  <span class="tocnum"><a href='#Page_120'>120-121</a></span><br />
+<span style="margin-left: 2.5em;">Aqueous Saponification</span>                   <span class="tocnum"><a href='#Page_121'>121</a></span><br />
+<span style="margin-left: 2.5em;">Splitting Fats with Ferments</span>              <span class="tocnum"><a href='#Page_121'>121-123</a></span><br />
+<span style="margin-left: 2.5em;">Krebitz Process</span>                    <span class="tocnum"><a href='#Page_123'>123-125</a></span><br />
+<br />
+<span style="margin-left: 1em;">2. Distillation of Fatty Acids</span>              <span class="tocnum"><a href='#Page_125'>125-126</a></span><br />
+<br />
+<br />
+CHAPTER VI.<br />
+<br />
+<span class="smcap">Analytical Methods</span>                                  <span class="tocnum"><a href='#Page_127'>127-164</a></span><br />
+<br />
+<span style="margin-left: 1em;">1. Analysis of Oils and Fats</span>                 <span class="tocnum"><a href='#Page_128'>128</a></span><br />
+<span style="margin-left: 2.5em;">Free Fatty Acids</span>                    <span class="tocnum"><a href='#Page_128'>128-130</a></span><br />
+<span style="margin-left: 2.5em;">Moisture</span>                          <span class="tocnum"><a href='#Page_130'>130</a></span><br />
+<span style="margin-left: 2.5em;">Titer</span>                         <span class="tocnum"><a href='#Page_130'>130-132</a></span><br />
+<span style="margin-left: 2.5em;">Determination of Unsaponifiable Matter</span>         <span class="tocnum"><a href='#Page_132'>132-133</a></span><br />
+<span style="margin-left: 2.5em;">Test for Color of Soap</span>                 <span class="tocnum"><a href='#Page_133'>133-134</a></span><br />
+<span style="margin-left: 2.5em;">Testing of Alkalis Used in Soap Making</span>         <span class="tocnum"><a href='#Page_134'>134-137</a></span><br />
+<br />
+<span style="margin-left: 1em;">2. Soap Analysis</span>                     <span class="tocnum"><a href='#Page_137'>137-138</a></span><br />
+<span style="margin-left: 2.5em;">Moisture </span>                       <span class="tocnum"><a href='#Page_138'>138-139</a></span><br />
+<span style="margin-left: 2.5em;">Free Alkali or Acid</span>                  <span class="tocnum"><a href='#Page_139'>139-142</a></span><br />
+<span style="margin-left: 2.5em;">Insoluble Matter</span>                      <span class="tocnum"><a href='#Page_143'>143</a></span><br />
+<span style="margin-left: 2.5em;">Starch and Gelatine</span>                  <span class="tocnum"><a href='#Page_143'>143-144</a></span><br />
+<span style="margin-left: 2.5em;">Total Fatty and Resin Acids</span>                <span class="tocnum"><a href='#Page_144'>144</a></span><br />
+<span style="margin-left: 2.5em;">Determination of Rosin</span>                 <span class="tocnum"><a href='#Page_144'>144-147</a></span><br />
+<span style="margin-left: 2.5em;">Total Alkali </span>                     <span class="tocnum"><a href='#Page_147'>147-148</a></span><br />
+<span style="margin-left: 2.5em;">Unsaponifiable Matter</span>                   <span class="tocnum"><a href='#Page_148'>148</a></span><br />
+<span style="margin-left: 2.5em;">Silica and Silicates</span>                  <span class="tocnum"><a href='#Page_148'>148-149</a></span><br />
+<span style="margin-left: 2.5em;">Glycerine in Soap</span>                   <span class="tocnum"><a href='#Page_149'>149-150</a></span><br />
+<span style="margin-left: 2.5em;">Sugar in Soap</span>                       <span class="tocnum"><a href='#Page_150'>150</a></span><br />
+<br />
+<span style="margin-left: 1em;">3. Glycerine Analysis</span>                   <span class="tocnum"><a href='#Page_150'>150-151</a></span><br />
+<span style="margin-left: 2.5em;">Sampling</span>                          <span class="tocnum"><a href='#Page_151'>151</a></span><br />
+<span style="margin-left: 2.5em;">Analysis</span>                        <span class="tocnum"><a href='#Page_151'>151-154</a></span><br />
+<span style="margin-left: 2.5em;">Acetin Process for the Determination of Glycerol</span>    <span class="tocnum"><a href='#Page_155'>155-156</a></span><br />
+<span style="margin-left: 2.5em;">The Method</span>                       <span class="tocnum"><a href='#Page_156'>156-159</a></span><br />
+<span style="margin-left: 2.5em;">Ways of Calculating Actual Glycerol Contents</span>      <span class="tocnum"><a href='#Page_159'>159-160</a></span><br />
+<span style="margin-left: 2.5em;">Bichromate Process for Glycerol Determination</span><br />
+<span style="margin-left: 3.5em;">Reagents Required</span>                  <span class="tocnum"><a href='#Page_160'>160-161</a></span><br />
+<span style="margin-left: 2.5em;">The Method</span>                       <span class="tocnum"><a href='#Page_161'>161-162</a></span><br />
+<span class='pagenum'><a name="Page_viii" id="Page_viii">[Pg viii]</a></span><span style="margin-left: 2.5em;">Sampling Crude Glycerine</span>                <span class="tocnum"><a href='#Page_162'>162-164</a></span><br />
+<br />
+<br />
+CHAPTER VII<br />
+<br />
+<span class="smcap">Standard Methods for the Sampling and Analysis of Commercial Fats and Oils</span>                            <span class="tocnum"><a href='#Page_165'>165-195</a></span><br />
+<br />
+<span style="margin-left: 1em;">1. Scope, Applicability and Limitations of the Methods</span>  <span class="tocnum"><a href='#Page_165'>165-166</a></span><br />
+<span style="margin-left: 2em;">Scope</span>                            <span class="tocnum"><a href='#Page_165'>165</a></span><br />
+<span style="margin-left: 2em;">Applicability </span>                       <span class="tocnum"><a href='#Page_166'>166</a></span><br />
+<span style="margin-left: 2em;">Limitations</span>                         <span class="tocnum"><a href='#Page_166'>166</a></span><br />
+<span style="margin-left: 2em;">Sampling</span>                        <span class="tocnum"><a href='#Page_166'>166-169</a></span><br />
+<span style="margin-left: 2em;">Tank Cars</span>                        <span class="tocnum"><a href='#Page_166'>166-167</a></span><br />
+<span style="margin-left: 2em;">Barrels, Tierces, Casks, Drums, and Other Packages</span>     <span class="tocnum"><a href='#Page_168'>168</a></span><br />
+<br />
+<span style="margin-left: 1em;">2. Analysis</span>                        <span class="tocnum"><a href='#Page_169'>169-183</a></span><br />
+<span style="margin-left: 2em;">Sample</span>                           <span class="tocnum"><a href='#Page_169'>169</a></span><br />
+<span style="margin-left: 2em;">Moisture and Volatile Matter</span>              <span class="tocnum"><a href='#Page_170'>170-172</a></span><br />
+<span style="margin-left: 2em;">Insoluble Impurities</span>                  <span class="tocnum"><a href='#Page_172'>172-173</a></span><br />
+<span style="margin-left: 2em;">Soluble Mineral Matter</span>                   <span class="tocnum"><a href='#Page_173'>173</a></span><br />
+<span style="margin-left: 2em;">Free Fatty Acids</span>                      <span class="tocnum"><a href='#Page_174'>174</a></span><br />
+<span style="margin-left: 2em;">Titer</span>                          <span class="tocnum"><a href='#Page_174'>174-175</a></span><br />
+<span style="margin-left: 2em;">Unsaponifiable Matter</span>                  <span class="tocnum"><a href='#Page_176'>176-177</a></span><br />
+<span style="margin-left: 2em;">Iodine Number-Wijs Method </span>               <span class="tocnum"><a href='#Page_177'>177-181</a></span><br />
+<span style="margin-left: 2em;">Saponification Number (Koettstorfer Number)</span>         <span class="tocnum"><a href='#Page_181'>181</a></span><br />
+<span style="margin-left: 2em;">Melting Point</span>                      <span class="tocnum"><a href='#Page_181'>181-182</a></span><br />
+<span style="margin-left: 2em;">Cloud Test</span>                       <span class="tocnum"><a href='#Page_182'>182-184</a></span><br />
+<br />
+<span style="margin-left: 1em;">3. Notes of the Above Methods </span>              <span class="tocnum"><a href='#Page_184'>184-196</a></span><br />
+<span style="margin-left: 2em;">Sampling </span>                         <span class="tocnum"><a href='#Page_183'>183</a></span><br />
+<span style="margin-left: 2em;">Moisture and Volatile Matter</span>              <span class="tocnum"><a href='#Page_184'>184-187</a></span><br />
+<span style="margin-left: 2em;">Insoluble Impurities</span>                    <span class="tocnum"><a href='#Page_187'>187</a></span><br />
+<span style="margin-left: 2em;">Soluble Mineral Matter</span>                 <span class="tocnum"><a href='#Page_187'>187-188</a></span><br />
+<span style="margin-left: 2em;">Free Fatty Acid</span>                     <span class="tocnum"><a href='#Page_188'>188-189</a></span><br />
+<span style="margin-left: 2em;">Titer  </span>                          <span class="tocnum"><a href='#Page_189'>189</a></span><br />
+<span style="margin-left: 2em;">Unsaponified Matter </span>                  <span class="tocnum"><a href='#Page_190'>190-193</a></span><br />
+<span style="margin-left: 2em;">Melting Point</span>                      <span class="tocnum"><a href='#Page_193'>193-196</a></span><br />
+<br />
+Plant and Machinery                                          <span class="tocnum"><a href='#Page_198'>198-219</a></span><br />
+<span style="margin-left: 2em;">Illustrations of Machinery and Layouts of the Plant of a Modern Soap Making Establishment</span>          <span class="tocnum"><a href='#Page_198'>198-219</a></span><br />
+<br />
+Appendix                                                     <span class="tocnum"><a href='#Page_219'>219-237</a></span><br />
+<br />
+<span style="margin-left: 2em;">Useful Tables</span><br />
+<br />
+Index                                                            <span class="tocnum"><a href='#Page_239'>239</a></span><br />
+</p>
+
+
+
+<hr style="width: 65%;" /><p><span class='pagenum'><a name="Page_1" id="Page_1">[Pg 1]</a></span></p>
+<h2>CHAPTER I</h2>
+
+<h3>Raw Materials Used in Soap Making.</h3>
+
+
+<p>Soap is ordinarily thought of as the common cleansing agent well known
+to everyone. In a general and strictly chemical sense this term is
+applied to the salts of the non-volatile fatty acids. These salts are
+not only those formed by the alkali metals, sodium and potassium, but
+also those formed by the heavy metals and alkaline earths. Thus we have
+the insoluble soaps of lime and magnesia formed when we attempt to wash
+in "hard water"; again aluminum soaps are used extensively in polishing
+materials and to thicken lubricating oils; ammonia or "benzine" soaps
+are employed among the dry cleaners. Commonly, however, when we speak of
+soap we limit it to the sodium or potassium salt of a higher fatty acid.</p>
+
+<p>It is very generally known that soap is made by combining a fat or oil
+with a water solution of sodium hydroxide (caustic soda lye), or
+potassium hydroxide (caustic potash). Sodium soaps are always harder
+than potassium soaps, provided the same fat or oil is used in both
+cases.</p>
+
+<p>The detergent properties of soap are due to the fact that it acts as an
+alkali regulator, that is, when water comes into contact with soap, it
+undergoes what is called hydrolytic dissociation. This means that it is
+broken down by water into other substances. Just what these substances
+are is subject to controversy, though it is presumed caustic alkali and
+the acid alkali salt of the fatty acids are formed.</p>
+
+
+<h3>OILS AND FATS.</h3>
+
+<p>There is no sharp distinction between fat and oil. By "oil" the layman
+has the impression of a liquid which at<span class='pagenum'><a name="Page_2" id="Page_2">[Pg 2]</a></span> warm temperature will flow as a
+slippery, lubricating, viscous fluid; by "fat" he understands a greasy,
+solid substance unctuous to the touch. It thus becomes necessary to
+differentiate the oils and fats used in the manufacture of soap.</p>
+
+<p>Inasmuch as a soap is the alkali salt of a fatty acid, the oil or fat
+from which soap is made must have as a constituent part, these fatty
+acids. Hydrocarbon oils or paraffines, included in the term "oil," are
+thus useless in the process of soap-making, as far as entering into
+chemical combination with the caustic alkalis is concerned. The oils and
+fats which form soap are those which are a combination of fatty acids
+and glycerine, the glycerine being obtained as a by-product to the
+soap-making industry.</p>
+
+
+<h3>NATURE OF A FAT OR OIL USED IN SOAP MANUFACTURE.</h3>
+
+<p>Glycerine, being a trihydric alcohol, has three atoms of hydrogen which
+are replaceable by three univalent radicals of the higher members of the
+fatty acids, <i>e. g.</i>,</p>
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'></td><td align='left'>OH</td><td align='left'></td><td align='left'>OR</td></tr>
+<tr><td align='left'>C<sub>3</sub> H<sub>5</sub></td><td align='left'>OH</td><td align='left'>+ 3 ROH = C<sub>3</sub> H<sub>5</sub></td><td align='left'>OR</td><td align='left'>+ 3 H<sub>2</sub>O</td></tr>
+<tr><td align='left'></td><td align='left'>OH</td><td align='left'></td><td align='left'>OR</td></tr>
+</table></div>
+
+
+<p class="center">Glycerine plus 3 Fatty Alcohols equals Fat or Oil plus 3 Water.</p>
+
+<p>Thus three fatty acid radicals combine with one glycerine to form a true
+neutral oil or fat which are called triglycerides. The fatty acids which
+most commonly enter into combination of fats and oils are lauric,
+myristic, palmitic, stearic and oleic acids and form the neutral oils or
+triglycerides derived from these, <i>e. g.</i>, stearin, palmatin, olein.
+Mono and diglycerides are also present in fats.</p>
+
+
+<h3>SAPONIFICATION DEFINED.</h3>
+
+<p>When a fat or oil enters into chemical combination with one of the
+caustic hydrates in the presence of water, the<span class='pagenum'><a name="Page_3" id="Page_3">[Pg 3]</a></span> process is called
+"saponification" and the new compounds formed are soap and glycerine,
+thus:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'></td><td align='left'>OR</td><td align='left'>&nbsp;</td><td align='left'>OH</td></tr>
+<tr><td align='left'>C<sub>3</sub>H<sub>5</sub></td><td align='left'>OR</td><td align='left'>+ 3 NaOH = C<sub>3</sub>H<sub>5</sub></td><td align='left'>OH</td><td align='left'>+ 3 NaOR</td></tr>
+<tr><td align='left'></td><td align='left'>OR</td><td align='left'>&nbsp;</td><td align='left'>OH</td></tr>
+</table></div>
+
+<p class="center">Fat or Oil plus 3 Sodium Hydrate equals Glycerine plus 3 Soap.</p>
+
+<p>It is by this reaction almost all of the soap used today is made.</p>
+
+<p>There are also other means of saponification, as, the hydrolysis of an
+oil or fat by the action of hydrochloric or sulfuric acid, by autoclave
+and by ferments or enzymes. By these latter processes the fatty acids
+and glycerine are obtained directly, no soap being formed.</p>
+
+
+<h3>FATS AND OILS USED IN SOAP MANUFACTURE.</h3>
+
+<p>The various and most important oils and fats used in the manufacture of
+soap are, tallow, cocoanut oil, palm oil, olive oil, poppy oil, sesame
+oil, soya bean oil, cotton-seed oil, corn oil and the various greases.
+Besides these the fatty acids, stearic, red oil (oleic acid) are more or
+less extensively used. These oils, fats and fatty acids, while they vary
+from time to time and to some extent as to their color, odor and
+consistency, can readily be distinguished by various physical and
+chemical constants.</p>
+
+<p>Much can be learned by one, who through continued acquaintance with
+these oils has thoroughly familiarized himself with the indications of a
+good or bad oil, by taste, smell, feel and appearance. It is, however,
+not well for the manufacturer in purchasing to depend entirely upon
+these simpler tests. Since he is interested in the yield of glycerine,
+the largest possible yield of soap per pound of soap stock and the
+general body and appearance of the finished product, the chemical tests
+upon which these depend<span class='pagenum'><a name="Page_4" id="Page_4">[Pg 4]</a></span> should be made. Those especially important are
+the acid value, percentage unsaponifiable matter and titer test.</p>
+
+<p>A short description of the various oils and fats mentioned is sufficient
+for their use in the soap industry.</p>
+
+<p><i>Tallow</i> is the name given to the fat extracted from the solid fat or
+"suet" of cattle, sheep or horses. The quality varies greatly, depending
+upon the seasons of the year, the food and age of the animal and the
+method of rendering. It comes to the market under the distinction of
+edible and inedible, a further distinction being made in commerce as
+beef tallow, mutton tallow or horse tallow. The better quality is white
+and bleaches whiter upon exposure to air and light, though it usually
+has a yellowish tint, a well defined grain and a clean odor. It consists
+chiefly of stearin, palmitin and olein. Tallow is by far the most
+extensively used and important fat in the making of soap.</p>
+
+<p>In the manufacture of soaps for toilet purposes, it is usually necessary
+to produce as white a product as possible. In order to do this it often
+is necessary to bleach the tallow before saponification. The method
+usually employed is the Fuller's Earth process.</p>
+
+
+<h3>FULLER'S EARTH PROCESS FOR BLEACHING TALLOW.</h3>
+
+<p>From one to two tons of tallow are melted out into the bleaching tank.
+This tank is jacketed, made of iron and provided with a good agitator
+designed to stir up sediment or a coil provided with tangential downward
+opening perforations and a draw-off cock at the bottom. The coil is the
+far simpler arrangement, more cleanly and less likely to cause trouble.
+By this arrangement compressed air which is really essential in the
+utilization of the press (see later) is utilized for agitation. A dry
+steam coil in an ordinary tank may be employed in place of a jacketed
+tank, which lessens the cost of installation.<span class='pagenum'><a name="Page_5" id="Page_5">[Pg 5]</a></span></p>
+
+<p>The tallow in the bleaching tank is heated to 180&deg; F. (82&deg; C.) and ten
+pounds of dry salt per ton of fat used added and thoroughly mixed by
+agitation. This addition coagulates any albumen and dehydrates the fat.
+The whole mass is allowed to settle over night where possible, or for at
+least five hours. Any brine which has separated is drawn off from the
+bottom and the temperature of the fat is then raised to 160&deg; F. (71&deg; C).</p>
+
+<p>Five per cent. of the weight of the tallow operated upon, of dry
+Fuller's earth is now added and the whole mass agitated from twenty to
+thirty minutes.</p>
+
+<p>The new bleached fat, containing the Fuller's earth is pumped directly
+to a previously heated filter press and the issuing clear oil run
+directly to the soap kettle.</p>
+
+<p>One of the difficulties experienced in the process is the heating of the
+press to a temperature sufficient to prevent solidification of the fat
+without raising the press to too great a temperature. To overcome this
+the first plate is heated by wet steam. Air delivered from a blower and
+heated by passage through a series of coils raised to a high temperature
+by external application of heat (super-heated steam) is then substituted
+for the steam. The moisture produced by the condensation of the steam is
+vaporized by the hot air and carried on gradually to each succeeding
+plate where it again condenses and vaporizes. In this way the small
+quantity of water is carried through the entire press, raising its
+temperature to 80&deg;-100&deg; C. This temperature is subsequently maintained
+by the passage of hot air. By this method of heating the poor
+conductivity of hot air is overcome through the intermediary action of a
+liquid vapor and the latent heat of steam is utilized to obtain the
+initial rise in temperature. To heat a small press economically where
+conditions are such that a large output is not required the entire
+press<span class='pagenum'><a name="Page_6" id="Page_6">[Pg 6]</a></span> may be encased in a small wooden house which can be heated by
+steam coils. The cake in the press is heated for some time after the
+filtration is complete to assist drainage. After such treatment the cake
+should contain approximately 15 per cent. fat and 25 per cent. water.
+The cake is now removed from the press and transferred to a small tank
+where it is treated with sufficient caustic soda to convert the fat
+content into soap.</p>
+
+<p>Saturated brine is then added to salt out the soap, the Fuller's earth
+is allowed to settle to the bottom of the tank and the soap which
+solidifies after a short time is skimmed off to be used in a cheap soap
+where color is not important. The liquor underneath may also be run off
+without disturbing the sediment to be used in graining a similar cheap
+soap. The waste Fuller's earth contains about 0.1 to 0.3 per cent. of
+fat.</p>
+
+
+<h3>METHOD FOR FURTHER IMPROVEMENT OF COLOR.</h3>
+
+<p>A further improvement of the color of the tallow may be obtained by
+freeing it from a portion of its free fatty acids, either with or
+without previous Fuller's earth bleaching.</p>
+
+<p>To carry out this process the melted fat is allowed to settle and as
+much water as possible taken off. The temperature is then raised to 160&deg;
+F. with dry steam and enough saturated solution of soda ash added to
+remove 0.5 per cent. of the free fatty acids, while agitating the mass
+thoroughly mechanically or by air. The agitation is continued ten
+minutes, the whole allowed to settle for two hours and the foots drawn
+off. The soap thus formed entangles a large proportion of the impurities
+of the fat.</p>
+
+
+<h3>VEGETABLE OILS.</h3>
+
+<p><i>Cocoanut Oil</i>, as the name implies, is obtained from the fruit of the
+cocoanut palm. This oil is a solid, white fat at ordinary temperature,
+having a bland taste and a characteristic<span class='pagenum'><a name="Page_7" id="Page_7">[Pg 7]</a></span> odor. It is rarely
+adulterated and is very readily saponified. In recent years the price of
+this oil has increased materially because cocoanut oil is now being used
+extensively for edible purposes, especially in the making of
+oleomargarine. Present indications are that shortly very little high
+grade oil will be employed for soap manufacture since the demand for
+oleomargarine is constantly increasing and since new methods of refining
+the oil for this purpose are constantly being devised.</p>
+
+<p>The oil is found in the market under three different grades: (1) Cochin
+cocoanut oil, the choicest oil comes from Cochin (Malabar). This
+product, being more carefully cultivated and refined than the other
+grades, is whiter, cleaner and contains a smaller percentage of free
+acid. (2) Ceylon cocoanut oil, coming chiefly from Ceylon, is usually of
+a yellowish tint and more acrid in odor than Cochin oil. (3) Continental
+cocoanut oil (Copra, Freudenberg) is obtained from the dried kernels,
+the copra, which are shipped to Europe in large quantities, where the
+oil is extracted. These dried kernels yield 60 to 70 per cent oil. This
+product is generally superior to the Ceylon oil and may be used as a
+very satisfactory substitute for Cochin oil, in soap manufacture,
+provided it is low in free acid and of good color. The writer has
+employed it satisfactorily in the whitest and finest of toilet soaps
+without being able to distinguish any disadvantage to the Cochin oil.
+Since continental oil is usually cheaper than Cochin oil, it is
+advisable to use it, as occasion permits.</p>
+
+<p>Cocoanut oil is used extensively in toilet soap making, usually in
+connection with tallow. When used alone the soap made from this oil
+forms a lather, which comes up rapidly but which is fluffy and dries
+quickly. A pure tallow soap lathers very much slower but produces a more
+lasting lather. Thus the advantage of using cocoanut oil<span class='pagenum'><a name="Page_8" id="Page_8">[Pg 8]</a></span> in soap is
+seen. It is further used in making a cocoanut oil soap by the cold
+process also for "fake" or filled soaps. The fatty acid content readily
+starts the saponification which takes place easily with a strong lye
+(25&deg;-35&deg; B.). Where large quantities of the oil are saponified care must
+be exercised as the soap formed suddenly rises or puffs up and may boil
+over. Cocoanut oil soap takes up large quantities of water, cases having
+been cited where a 500 per cent. yield has been obtained. This water of
+course dries out again upon exposure to the air. The soap is harsh to
+the skin, develops rancidity and darkens readily.</p>
+
+<p><i>Palm Kernel Oil</i>, which is obtained from the kernels of the palm tree
+of West Africa, is used in soap making to replace cocoanut oil where the
+lower price warrants its use. It resembles cocoanut oil in respect to
+saponification and in forming a very similar soap. Kernel oil is white
+in color, has a pleasant nutty odor when fresh, but rapidly develops
+free acid, which runs to a high percentage.</p>
+
+<p><i>Palm Oil</i> is produced from the fruit of the several species of the palm
+tree on the western coast of Africa generally, but also in the
+Philippines. The fresh oil has a deep orange yellow tint not destroyed
+by saponification, a sweetish taste and an odor of orris root or violet
+which is also imparted to soap made from it. The methods by which the
+natives obtain the oil are crude and depend upon a fermentation, or
+putrefaction. Large quantities are said to be wasted because of this
+fact. The oil contains impurities in the form of fermentable fibre and
+albuminous matter, and consequently develops free fatty acid rapidly.
+Samples tested for free acid have been found to have hydrolized
+completely and one seldom obtains an oil with low acid content. Because
+of this high percentage of free fatty acid, the glycerine yield is
+small, though the neutral oil should produce approximately 12 per cent.
+glycerine. Some<span class='pagenum'><a name="Page_9" id="Page_9">[Pg 9]</a></span> writers claim that glycerine exists in the free state
+in palm oil. The writer has washed large quantities of the oil and
+analyzed the wash water for glycerine. The results showed that the
+amount present did not merit its recovery. Most soap makers do not
+attempt to recover the glycerine from this oil, when used alone for soap
+manufacture.</p>
+
+<p>There are several grades of palm oil in commerce, but in toilet soap
+making it is advisable to utilize only Lagos palm oil, which is the best
+grade. Where it is desired to maintain the color of the soap this oil
+produces, a small quantity of the lower or "brass" grade of palm oil may
+be used, as the soap made from the better grades of oil gradually
+bleaches and loses its orange yellow color.</p>
+
+<p>Palm oil produces a crumbly soap which cannot readily be milled and is
+termed "short." When used with tallow and cocoanut oil, or 20 to 25 per
+cent. cocoanut oil, it produces a very satisfactory toilet soap. In the
+saponification of palm oil it is not advisable to combine it with tallow
+in the kettle, as the two do not readily mix.</p>
+
+<p>Since the finished soap has conveyed to it the orange color of the oil,
+the oil is bleached before saponification. Oxidation readily destroys
+the coloring matter, while heat and light assist materially. The methods
+generally employed are by the use of oxygen developed by bichromates and
+hydrochloric acid and the direct bleaching through the agency of the
+oxygen of the air.</p>
+
+
+<h3>CHROME BLEACHING OF PALM OIL.</h3>
+
+<p>The chrome process of bleaching palm oil is more rapid and the oxygen
+thus derived being more active will bleach oils which air alone cannot.
+It depends upon the reaction:</p>
+
+<p class="center">
+Na<sub>2</sub>Cr<sub>2</sub>O<sub>7</sub> + 8HCl = Cr<sub>2</sub>Cl<sub>6</sub> + 2NaCl + 7O.<br />
+</p>
+
+<p>in which the oxygen is the active principle. In practice it is found
+necessary to use an excess of acid over that theoretically indicated.<span class='pagenum'><a name="Page_10" id="Page_10">[Pg 10]</a></span></p>
+
+<p>For the best results an oil should be chosen containing under 2 per
+cent. impurities and a low percentage of free fatty acids. Lagos oil is
+best adapted to these requirements. The oil is melted by open steam from
+a jet introduced through the bung, the melted oil and condensed water
+running to the store tank through two sieves (about 1/8 inch mesh) to
+remove the fibrous material and gross impurities. The oil thus obtained
+contains fine earthy and fibrous material and vegetable albuminous
+matter which should be removed, as far as possible, since chemicals are
+wasted in their oxidation and they retard the bleaching. This is best
+done by boiling the oil for one hour with wet steam and 10 per cent.
+solution of common salt (2 per cent. dry salt on weight of oil used) in
+a lead-lined or wooden tank. After settling over night the brine and
+impurities are removed by running from a cock at the bottom of the vat
+and the oil is run out into the bleaching tank through an oil cock,
+situated about seven inches from the bottom.</p>
+
+<p>The bleaching tank is a lead-lined iron tank of the approximate
+dimensions of 4 feet deep, 4 feet long and 3-1/2 feet wide, holding
+about 1-1/2 tons. The charge is one ton. A leaden outlet pipe is fixed
+at the bottom, to which is attached a rubber tube closed by a screw
+clip. A plug also is fitted into the lead outlet pipe from above. Seven
+inches above the lower outlet is affixed another tap through which the
+oil is drawn off.</p>
+
+<p>The tank is further equipped with a wet steam coil and a coil arranged
+to allow thorough air agitation, both coils being of lead. A good
+arrangement is to use one coil to deliver either air or steam. These
+coils should extend as nearly as possible over the entire bottom of the
+tank and have a number of small downward perforations, so as to spread
+the agitation throughout the mass.</p>
+
+<p>The temperature of the oil is reduced by passing in air<span class='pagenum'><a name="Page_11" id="Page_11">[Pg 11]</a></span> to 110&deg; F. and
+40 pounds of fine common salt per ton added through a sieve. About
+one-half of the acid (40 pounds of concentrated commercial hydrochloric
+acid) is now poured in and this is followed by the sodium bichromate in
+concentrated solution, previously prepared in a small lead vat or
+earthen vessel by dissolving 17 pounds of bichromate in 45 pounds
+commercial hydrochloric acid. This solution should be added slowly and
+should occupy three hours, the whole mass being thoroughly agitated with
+air during the addition and for one hour after the last of the bleaching
+mixture has been introduced. The whole mixture is now allowed to settle
+for one hour and the exhausted chrome liquors are then run off from the
+lower pipe to a waste tank. About 40 gallons of water are now run into
+the bleached oil and the temperature raised by open steam to 150&deg; to
+160&deg; F. The mass is then allowed to settle over night.</p>
+
+<p>One such wash is sufficient to remove the spent chrome liquor
+completely, provided ample time is allowed for settling. A number of
+washings given successively with short periods of settling do not remove
+the chrome liquors effectually. The success of the operation depends
+entirely upon the completeness of settling.</p>
+
+<p>The wash water is drawn off as before and the clear oil run to storage
+tanks or to the soap kettle through the upper oil cock.</p>
+
+<p>The waste liquors are boiled with wet steam and the oil skimmed from the
+surface, after which the liquors are run out through an oil trap.</p>
+
+<p>By following the above instructions carefully it is possible to bleach
+one ton of palm oil with 17 pounds of bichromate of soda and 85 pounds
+hydrochloric acid.</p>
+
+<p>The spent liquors should be a bright green color. Should they be of a
+yellow or brownish shade insufficient acid has<span class='pagenum'><a name="Page_12" id="Page_12">[Pg 12]</a></span> been allowed and more
+must be added to render the whole of the oxygen available.</p>
+
+<p>If low grade oils are being treated more chrome will be necessary, the
+amount being best judged by conducting the operation as usual and after
+the addition of the bichromate, removing a sample of the oil, washing
+the sample and noting the color of a rapidly cooled sample.</p>
+
+<p>A little practice will enable the operator to judge the correspondence
+between the color to be removed and the amount of bleaching mixture to
+be added.</p>
+
+<p>To obtain success with this process the method of working given must be
+adhered to even in the <i>smallest detail</i>. This applies to the
+temperature at which each operation is carried out particularly.</p>
+
+
+<h3>AIR BLEACHING OF PALM OIL.</h3>
+
+<p>The method of conducting this process is identical with the chrome
+process to the point where the hydrochloric acid is to be added to the
+oil. In this method no acid or chrome is necessary, as the active
+bleaching agent is the oxygen of the air.</p>
+
+<p>The equipment is similar to that of the former process, except that a
+wooden tank in which no iron is exposed will suffice to bleach the oil
+in. The process depends in rapidity upon the amount of air blown through
+the oil and its even distribution. Iron should not be present or exposed
+to the oil during bleaching, as it retards the process considerably.</p>
+
+<p>After the impurities have been removed, as outlined under the chrome
+process, the temperature of the oil is raised by open steam to boiling.
+The steam is then shut off and air allowed to blow through the oil until
+it is completely bleached, the temperature being maintained above 150&deg;
+F. by occasionally passing in steam. Usually a ton of oil is readily and
+completely bleached after the air has<span class='pagenum'><a name="Page_13" id="Page_13">[Pg 13]</a></span> been passed through it for 18 to
+20 hours, provided the oil is thoroughly agitated by a sufficient flow
+of air.</p>
+
+<p>If the oil has been allowed to settle over night, it is advisable to run
+off the condensed water and impurities by the lower cock before
+agitating again the second day.</p>
+
+<p>When the oil has been bleached to the desired color, which can be
+determined by removing a sample and cooling, the mass is allowed to
+settle, the water run off to a waste tank from which any oil carried
+along may be skimmed off and the supernatant clear oil run to the
+storage or soap kettle.</p>
+
+<p>In bleaching by this process, while the process consumes more time and
+is not as efficient in bleaching the lower grade oils, the cost of
+bleaching is less and with a good oil success is more probable, as there
+is no possibility of any of the chrome liquors being present in the oil.
+These give the bleached oil a green tint when the chrome method is
+improperly conducted and they are not removed.</p>
+
+<p>Instead of blowing the air through it, the heater oil may be brought
+into contact with the air, either by a paddle wheel arrangement, which,
+in constantly turning, brings the oil into contact with the air, or by
+pumping the heated oil into an elevated vessel, pierced with numerous
+fine holes from which the oil continuously flows back into the vessel
+from which the oil is pumped. While in these methods air, light and heat
+act simultaneously in the bleaching of the oil, the equipment required
+is too cumbersome to be practical.</p>
+
+<p>Recent investigations<a name="FNanchor_1_1" id="FNanchor_1_1"></a><a href="#Footnote_1_1" class="fnanchor">[1]</a> in bleaching palm oil by oxygen have shown that
+not only the coloring matter but the oil itself was affected. In
+bleaching palm oil for 30 hours with air the free fatty acid content
+rose and titer decreased considerably.<span class='pagenum'><a name="Page_14" id="Page_14">[Pg 14]</a></span></p>
+
+<p><i>Olive Oil</i>, which comes from the fruit of the olive trees, varies
+greatly in quality, according to the method by which it is obtained and
+according to the tree bearing the fruit. Three hundred varieties are
+known in Italy alone. Since the larger portion of olive oil is used for
+edible purposes, a lower grade, denatured oil, denatured because of the
+tariff, is used for soap manufacture in this country. The oil varies in
+color from pale green to golden yellow. The percentage of free acid in
+this oil varies greatly, though the oil does not turn rancid easily. It
+is used mainly in the manufacture of white castile soap.</p>
+
+<p>Olive oil foots, which is the oil extracted by solvents after the better
+oil is expressed, finds its use in soap making mostly in textile soaps
+for washing and dyeing silks and in the production of green castile
+soaps.</p>
+
+<p>Other oils, as poppy seed oil, sesame oil, cottonseed oil, rape oil,
+peanut (arachis) oil, are used as adulterants for olive oil, also as
+substitutes in the manufacture of castile soap, since they are cheaper
+than olive oil.</p>
+
+<p><i>Cottonseed Oil</i> is largely used in the manufacture of floating and
+laundry soaps. It may be used for toilet soaps where a white color is
+not desired, as yellow spots appear on a finished soap in which it has
+been used after having been in stock a short time.</p>
+
+<p><i>Corn Oil and Soya Bean Oil</i> are also used to a slight extent in the
+manufacture of toilet soaps, although the oils form a soap of very
+little body. Their soaps also spot yellow on aging.</p>
+
+<p>Corn oil finds its greatest use in the manufacture of soap for washing
+automobiles. It is further employed for the manufacture of cheap liquid
+soaps.</p>
+
+<p><i>Fatty Acids</i> are also used extensively in soap manufacture. While the
+soap manufacturer prefers to use a neutral oil or fat, since from these
+the by-product glycerine is<span class='pagenum'><a name="Page_15" id="Page_15">[Pg 15]</a></span> obtained, circumstances arise where it is
+an advantage to use the free fatty acids. Red oil (oleic acid, elaine)
+and stearic acid are the two fatty acids most generally bought for soap
+making. In plants using the Twitchell process, which consists in
+splitting the neutral fats and oils into fatty acids and glycerine by
+dilute sulphuric acid and producing their final separation by the use of
+so-called aromatic sulphonic acids, these fatty acids consisting of a
+mixture of oleic, stearic, palmitic acids, etc., are used directly after
+having been purified by distillation, the glycerine being obtained from
+evaporating the wash water.</p>
+
+<p>Oleic acid (red oil) and stearic acid are obtained usually by the
+saponification of oils, fats and greases by acid, lime or water under
+pressure or Twitchelling. The fatty acids thus are freed from their
+combination with glycerine and solidify upon cooling, after which they
+are separated from the water and pressed at a higher or lower
+temperature. The oleic acid, being liquid at ordinary temperature,
+together with some stearic and palmitic acid, is thus pressed out. These
+latter acids are usually separated by distillation, combined with the
+press cake further purified and sold as stearic acid.</p>
+
+<p>The red oil, sometimes called saponified red oil, is often semi-solid,
+resembling a soft tallow, due to the presence of stearic acid. The
+distilled oils are usually clear, varying in color from light to a deep
+brown. Stearic acid, which reaches the trade in slab form, varies in
+quality from a soft brown, greasy, crumbly solid of unpleasant odor to a
+snow white, wax-like, hard, odorless mass. The quality of stearic acid
+is best judged by the melting point, since the presence of any oleic
+acid lowers this. The melting point of the varieties used in soap
+manufacture usually ranges from 128&deg; to 132&deg; F. Red oil is used in the
+manufacture of textile soaps, replacing olive oil foots soap for<span class='pagenum'><a name="Page_16" id="Page_16">[Pg 16]</a></span> this
+purpose, chlorophyll being used to color the soap green. Stearic acid,
+being the hard firm fatty acid, may be used in small quantities to give
+a better grade of soap body and finish. In adding this substance it
+should always be done in the crutcher, as it will not mix in the kettle.
+It finds its largest use for soap, however, in the manufacture of
+shaving soaps and shaving creams, since it produces the non-drying
+creamy lather so greatly desired for this purpose. Both red oil and
+stearic acid being fatty acids, readily unite with the alkali
+carbonates, carbon dioxide being formed in the reaction and this method
+is extensively used in the formation of soap from them.</p>
+
+
+<h3>RANCIDITY OF OILS AND FATS.</h3>
+
+<p>Rancidity in neutral oils and fats is one of the problems the soap
+manufacturer has to contend with. The mere saying that an oil is rancid
+is no indication of its being high in free acid. The two terms rancidity
+and acidity are usually allied. Formerly, the acidity of a fat was
+looked upon as the direct measure of its rancidity. This idea is still
+prevalent in practice and cannot be too often stated as incorrect. Fats
+and oils may be <i>acid</i>, or <i>rancid</i>, or <i>acid and rancid</i>. In an acid
+fat there has been a hydrolysis of the fat and it has developed a rather
+high percentage of free acid. A rancid fat is one in which have been
+developed compounds of an odoriferous nature. An acid and rancid fat is
+one in which both free acid and organic compounds of the well known
+disagreeable odors have been produced.</p>
+
+<p>It cannot be definitely stated just how this rancidity takes place, any
+more than just what are the chemical products causing rancidity. The
+only conclusion that one may draw is that the fats are first hydrolyzed
+or split up into glycerine and free fatty acids. This is followed by an
+oxidation of the products thus formed.<span class='pagenum'><a name="Page_17" id="Page_17">[Pg 17]</a></span></p>
+
+<p>Moisture, air, light, enzymes (organized ferments) and bacteria are all
+given as causes of rancidity.</p>
+
+<p>It seems very probable that the initial splitting of the fats is caused
+by enzymes, which are present in the seeds and fruits of the vegetable
+oils and tissue of animal fats, in the presence of moisture. Lewkowitsch
+strongly emphasizes this point and he is substantiated in his idea by
+other authorities. Others hold that bacteria or micro-organisms are the
+cause of this hydrolysis, citing the fact that they have isolated
+various micro-organisms from various fats and oils. The acceptance of
+the bacterial action would explain the various methods of preservation
+of oils and fats by the use of antiseptic preparations. It cannot,
+however, be accepted as a certainty that bacteria cause the rancidity of
+fats.</p>
+
+<p>The action of enzymes is a more probable explanation.</p>
+
+<p>The hydrolysis of fats and oils is accelerated when they are allowed to
+remain for some time in the presence of organic non-fats. Thus, palm
+oil, lower grades of olive oil, and tallow, which has been in contact
+with the animal tissue for a long time, all contain other nitrogenous
+matter and exhibit a larger percentage of free fatty acid than the oils
+and fats not containing such impurities.</p>
+
+<p>Granting this initial splitting of the fat into free fatty acids and
+glycerine, this is not a sufficient explanation. The products thus
+formed must be acted upon by air and light. It is by the action of these
+agents that there is a further action upon the products, and from this
+oxidation we ascertain by taste and smell (chemical means are still
+unable to define rancidity) whether or not a fat is rancid. While some
+authorities have presumed to isolate some of these products causing
+rancidity, we can only assume the presence of the various possible
+compounds produced by the action<span class='pagenum'><a name="Page_18" id="Page_18">[Pg 18]</a></span> of air and light which include oxy
+fatty acids, lactones, alcohols, esters, aldehydes and other products.</p>
+
+<p>The soap manufacturer is interested in rancidity to the extent of the
+effect upon the finished soap. Rancid fats form darker soaps than fats
+in the neutral state, and very often carry with them the disagreeable
+odor of a rancid oil. Further, a rancid fat or oil is usually high in
+free acid. It is by no means true, however, that rancidity is a measure
+for acidity, for as has already been pointed out, an oil may be rancid
+and not high in free acid.</p>
+
+<p>The percentage of free fatty acid is of even greater importance in the
+soap industry. The amount of glycerine yield is dependent upon the
+percentage of free fatty acid and is one of the criterions of a good fat
+or oil for soap stock.</p>
+
+
+<h3>PREVENTION OF RANCIDITY.</h3>
+
+<p>Since moisture, air, light and enzymes, produced by the presence of
+organic impurities, are necessary for the rancidity of a fat or oil, the
+methods of preventing rancidity are given. Complete dryness, complete
+purification of fats and oils and storage without access of air or light
+are desirable. Simple as these means may seem, they can only be
+approximated in practice. The most difficult problem is the removal of
+the last trace of moisture. Impurities may be lessened very often by the
+use of greater care. In storing it is well to store in closed barrels or
+closed iron tanks away from light, as it has been observed that oils and
+fats in closed receptacles become rancid less rapidly than those in open
+ones, even though this method of storing is only partially attained.
+Preservatives are also used, but only in edible products, where their
+effectiveness is an open question.</p>
+
+
+<h3>CHEMICAL CONSTANTS OF OILS AND FATS.</h3>
+
+<p>Besides the various physical properties of oils and fats,<span class='pagenum'><a name="Page_19" id="Page_19">[Pg 19]</a></span> such as
+color, specific gravity, melting point, solubility, etc., they may be
+distinguished chemically by a number of chemical constants. These are
+the iodine number, the acetyl value, saponification number,
+Reichert-Meissl number for volatile acids, Hehner number for insoluble
+acids. These constants, while they vary somewhat with any particular oil
+or fat, are more applicable to the edible products and are criterions
+where any adulteration of fat or oil is suspected. The methods of
+carrying out the analyses of oils and fats to obtain these constants are
+given in the various texts<a name="FNanchor_2_2" id="FNanchor_2_2"></a><a href="#Footnote_2_2" class="fnanchor">[2]</a> on oils and fats, and inasmuch as they are
+not of great importance to the soap industry they are merely mentioned
+here.</p>
+
+
+<h3>OIL HARDENING OR HYDROGENATING.</h3>
+
+<p>It is very well known that oils and fats vary in consistency and
+hardness, depending upon the glycerides forming same. Olein, a
+combination of oleic acid and glycerine, as well as oleic acid itself
+largely forms the liquid portion of oils and fats. Oleic acid
+(C<sub>18</sub>H<sub>34</sub>O<sub>2</sub>) is an unsaturated acid and differs from stearic acid
+(C<sub>18</sub>H<sub>36</sub>O<sub>2</sub>), the acid forming the hard firm portion of oils and
+fats, by containing two atoms of hydrogen less in the molecule.
+Theoretically it should be a simple matter to introduce two atoms of
+hydrogen into oleic acid or olein, and by this mere addition convert
+liquid oleic acid and olein into solid stearic acid and stearine.</p>
+
+<p>For years this was attempted and all attempts to apply the well known
+methods of reduction (addition of hydrogen) in organic chemistry, such
+as treatment with tin and acid, sodium amalgam, etc., were unsuccessful.
+In recent years, however, it has been discovered that in the presence of
+a catalyzer, nickel in finely divided form<span class='pagenum'><a name="Page_20" id="Page_20">[Pg 20]</a></span> or the oxides of nickel are
+usually employed, the process of hydrogenating an oil is readily
+attained upon a practical basis.</p>
+
+<p>The introduction of hardened oils has opened a new source of raw
+material for the soap manufacturer in that it is now possible to use
+oils in soap making which were formerly discarded because of their
+undesirable odors. Thus fish or train oils which had up to the time of
+oil hydrogenating resisted all attempts of being permanently deodorized,
+can now be employed very satisfactorily for soap manufacture. A Japanese
+chemist, Tsujimoto<a name="FNanchor_3_3" id="FNanchor_3_3"></a><a href="#Footnote_3_3" class="fnanchor">[3]</a> has shown that fish oils contain an unsaturated
+acid of the composition C<sub>18</sub>H<sub>28</sub>O<sub>2</sub>, for which he proposed the
+name clupanodonic acid. By the catalytic hardening of train oils this
+acid passes to stearic acid and the problem of deodorizing these oils is
+solved.<a name="FNanchor_4_4" id="FNanchor_4_4"></a><a href="#Footnote_4_4" class="fnanchor">[4]</a></p>
+
+<p>At first the introduction of hardened oils for soap manufacture met with
+numerous objections, due to the continual failures of obtaining a
+satisfactory product by the use of same. Various attempts have now shown
+that these oils, particularly hardened train oils, produce
+extraordinarily useful materials for soap making. These replace
+expensive tallow and other high melting oils. It is of course impossible
+to employ hardened oils alone, as a soap so hard would thus be obtained
+that it would be difficultly soluble in water and possess very little
+lathering quality. By the addition of 20-25% of tallow oil or some other
+oil forming a soft soap a very suitable soap for household use may be
+obtained. Ribot<a name="FNanchor_5_5" id="FNanchor_5_5"></a><a href="#Footnote_5_5" class="fnanchor">[5]</a> discusses this matter fully. Hardened oils readily
+saponify, may be<span class='pagenum'><a name="Page_21" id="Page_21">[Pg 21]</a></span> perfumed without any objections and do not impart any
+fishy odor to an article washed with same. Meyerheim<a name="FNanchor_6_6" id="FNanchor_6_6"></a><a href="#Footnote_6_6" class="fnanchor">[6]</a> states that
+through the use of hydrogenated oils the hardness of soap is
+extraordinarily raised, so that soap made from hardened cottonseed oil
+is twelve times as hard as the soap made from ordinary cottonseed oil.
+This soap is also said to no longer spot yellow upon aging, and as a
+consequence of its hardness, is able to contain a considerably higher
+content of rosin through which lathering power and odor may be improved.
+Hardened oils can easily be used for toilet soap bases, provided they
+are not added in too great a percentage.</p>
+
+<p>The use of hardened oils is not yet general, but there is little doubt
+that the introduction of this process goes a long way toward solving the
+problem of cheaper soap material for the soap making industry.</p>
+
+
+<h3>GREASE.</h3>
+
+<p>Grease varies so greatly in composition and consistency that it can
+hardly be classed as a distinctive oil or fat. It is obtained from
+refuse, bones, hides, etc., and while it contains the same constituents
+as tallow, the olein content is considerably greater, which causes it to
+be more liquid in composition. Grease differs in color from an off-white
+to a dark brown. The better qualities are employed in the manufacture of
+laundry and chip soap, while the poorer qualities are only fit for the
+cheapest of soaps used in scrubbing floors and such purposes. There is
+usually found in grease a considerable amount of gluey matter, lime and
+water. The percentage of free fatty acid is generally high.</p>
+
+<p>The darker grades of grease are bleached before being used. This is done
+by adding a small quantity of sodium nitrate to the melted grease and
+agitating, then<span class='pagenum'><a name="Page_22" id="Page_22">[Pg 22]</a></span> removing the excess saltpeter by decomposing with
+sulphuric acid. A better method of refining, however, is by
+distillation. The chrome bleach is also applicable.</p>
+
+
+<h3>ROSIN (COLOPHONY, YELLOW ROSIN, RESINA).</h3>
+
+<p>Rosin is the residue which remains after the distillation of turpentine
+from the various species of pines. The chief source of supply is in the
+States of Georgia North and South Carolina. It is a transparent, amber
+colored hard pulverizable resin. The better grades are light in color
+and known as water white (w. w.) and window glass (w. g.). These are
+obtained from a tree which has been tapped for the first year. As the
+same trees are tapped from year to year, the product becomes deeper and
+darker in color until it becomes almost black.</p>
+
+<p>The constituents of rosin are chiefly (80-90%) abietic acid or its
+anhydride together with pinic and sylvic acids. Its specific gravity is
+1.07-1.08, melting point about 152.5 C., and it is soluble in alcohol,
+ether, benzine, carbon disulfide, oils, alkalis and acetic acid. The
+main use of rosin, outside of the production of varnishes, is in the
+production of laundry soaps, although a slight percentage acts as a
+binder and fixative for perfumes in toilet soaps and adds to their
+detergent properties. Since it is mainly composed of acids, it readily
+unites with alkaline carbonates, though the saponification is not quite
+complete and the last portion must be completed through the use of
+caustic hydrates, unless an excess of 10% carbonate over the theoretical
+amount is used. A lye of 20&deg; B. is best adapted to the saponification of
+rosin when caustic hydrates are employed for this purpose, since weak
+lyes cause frothing. While it is sometimes considered that rosin is an
+adulterant for soap, this is hardly justifiable, as it adds to the
+cleansing properties of soap. Soaps containing<span class='pagenum'><a name="Page_23" id="Page_23">[Pg 23]</a></span> rosin are of the well
+known yellowish color common to ordinary laundry soaps. The price of
+rosin has so risen in the last few years that it presents a problem of
+cost to the soap manufacturer considering the price at which laundry
+soaps are sold.</p>
+
+
+<h3>ROSIN SAPONIFICATION.</h3>
+
+<p>As has been stated, rosin may be saponified by the use of alkaline
+carbonates. On account of the possibility of the soap frothing over, the
+kettle in which the operation takes place should be set flush with the
+floor, which ought to be constructed of cement. The kettle itself is an
+open one with round bottom, equipped with an open steam coil and skimmer
+pipe, and the open portion is protected by a semi-circular rail. A
+powerful grid, having a 3-inch mesh, covers one-half of the kettle, the
+sharp edges protruding upwards.</p>
+
+<p>The staves from the rosin casks are removed at the edge of the kettle,
+the rosin placed on the grid and beaten through with a hammer to break
+it up into small pieces.</p>
+
+<p>To saponify a ton of rosin there are required 200 lbs. soda ash, 1,600
+lbs. water and 100 lbs. salt. Half the water is run into the kettle,
+boiled, and then the soda ash and half the salt added. The rosin is now
+added through the grid and the mixture thoroughly boiled. As carbon
+dioxide is evolved by the reaction the boiling is continued for one hour
+to remove any excess of this gas. A portion of the salt is gradually
+added to grain the soap well and to keep the mass in such condition as
+to favor the evolution of gas. The remainder of the water is added to
+close the soap and boiling continued for one or two hours longer. At
+this point the kettle must be carefully watched or it will boil over
+through the further<span class='pagenum'><a name="Page_24" id="Page_24">[Pg 24]</a></span> escape of carbon dioxide being hindered. The mass,
+being in a frothy condition, will rapidly settle by controlling the flow
+of steam. The remaining salt is then scattered in and the soap allowed
+to settle for two hours or longer. The lyes are then drained off the
+top. If the rosin soap is required for toilet soaps, it is grained a
+second time. The soap is now boiled with the water caused by the
+condensation of the steam, which changes it to a half grained soap
+suitable for pumping. A soap thus made contains free soda ash 0.15% or
+less, free rosin about 15%. The mass is then pumped to the kettle
+containing the soap to which it is to be added at the proper stage. The
+time consumed in thus saponifying rosin is about five hours.</p>
+
+
+<h3>NAPHTHENIC ACIDS.</h3>
+
+<p>The naphtha or crude petroleum of the various provinces in Europe, as
+Russia, Galacia, Alsace and Roumania yield a series of bodies of acid
+character upon refining which are designated under the general name of
+naphthenic acids. These acids are retained in solution in the alkaline
+lyes during the distillation of the naphtha in the form of alkaline
+naphthenates. Upon adding dilute sulphuric acid to these lyes the
+naphthenates are decomposed and the naphthenic acids float to the
+surface in an oily layer of characteristic disagreeable odor and varying
+from yellow to brown in color<a name="FNanchor_7_7" id="FNanchor_7_7"></a><a href="#Footnote_7_7" class="fnanchor">[7]</a>. In Russia particularly large
+quantities of these acids are employed in the manufacture of soap.</p>
+
+<p>The soaps formed from naphthenic acids have recently been
+investigated<a name="FNanchor_8_8" id="FNanchor_8_8"></a><a href="#Footnote_8_8" class="fnanchor">[8]</a> and found to resemble the soaps made from cocoanut oil
+and palm kernel oil, in that they are<span class='pagenum'><a name="Page_25" id="Page_25">[Pg 25]</a></span> difficult to salt out and
+dissociate very slightly with water. The latter property makes them
+valuable in textile industries when a mild soap is required as a
+detergent, e. g., in the silk industry. These soaps also possess a high
+solvent power for mineral oils and emulsify very readily. The mean
+molecular weight of naphthenic acids themselves is very near that of the
+fatty acids contained in cocoanut oil, and like those of cocoanut oil a
+portion of the separated acids are volatile with steam. The iodine
+number indicates a small content of unsaturated acids.</p>
+
+<p>That naphthenic acids are a valuable soap material is now recognized,
+but except in Russia the soap is not manufactured to any extent at the
+present time.</p>
+
+
+<h3>ALKALIS.</h3>
+
+<p>The common alkali metals which enter into the formation of soap are
+sodium and potassium. The hydroxides of these metals are usually used,
+except in the so called carbonate saponification of free fatty acids in
+which case sodium and potassium carbonate are used. A water solution of
+the caustic alkalis is known as lye, and it is as lyes of various
+strengths that they are added to oils and fats to form soap. The density
+or weight of a lye is considerably greater than that of water, depending
+upon the amount of alkali dissolved, and its weight is usually
+determined by a hydrometer. This instrument is graduated by a
+standardized scale, and while all hydrometers should read alike in a
+liquid of known specific gravity, this is generally not the case, so
+that it is advisable to check a new hydrometer for accurate work against
+one of known accuracy. In this country the Baum&eacute; scale has been adopted,
+while in England a different graduation known as the Twaddle scale is
+used. The strength of a lye or any solution is determined by the
+distance the instrument<span class='pagenum'><a name="Page_26" id="Page_26">[Pg 26]</a></span> sinks into the solution, and we speak of the
+strength of a solution as so many degrees Baum&eacute; or Twaddle which are
+read to the point where the meniscus of the lye comes on the graduated
+scale. Hydrometers are graduated differently for liquids of different
+weights. In the testing of lyes one which is graduated from 0&deg; to 50&deg; B.
+is usually employed.</p>
+
+<p><i>Caustic soda</i> is received by the consumer in iron drums weighing
+approximately 700 lbs. each. The various grades are designated as 60,
+70, 74, 76 and 77%. These percentages refer to the percentage of sodium
+oxide (Na<sub>2</sub>O) in 100 parts of pure caustic soda formed by the
+combination of 77-1/2 parts of sodium oxide and 22-1/2 parts of water,
+77-1/2% being chemically pure caustic soda. There are generally
+impurities present in commercial caustic soda. These consist of sodium
+carbonate, sodium chloride or common salt and sometimes lime. It is
+manufactured by treating sodium carbonate in an iron vessel with calcium
+hydroxide or slaked lime, or by electrolysis of common salt. The latter
+process has yet been unable to compete with the former in price.
+Formerly all the caustic soda used in soap making was imported, and it
+was only through the American manufacturer using a similar container to
+that used by foreign manufacturers that they were able to introduce
+their product. This prejudice has now been entirely overcome and most of
+the caustic soda used in this country is manufactured here.</p>
+
+
+<h3>CAUSTIC POTASH.</h3>
+
+<p>The output of the salts containing potassium is controlled almost
+entirely by Germany. Formerly the chief source of supply of potassium
+compounds was from the burned ashes of plants, but about fifty years ago
+the inexhaustible salt mines of Stassfurt, Germany, were discovered.<span class='pagenum'><a name="Page_27" id="Page_27">[Pg 27]</a></span>
+The salt there mined contains, besides the chlorides and sulphates of
+sodium, magnesium, calcium and other salts, considerable quantities of
+potassium chloride, and the Stassfurt mines at present are practically
+the entire source of all potassium compounds, in spite of the fact that
+other localities have been sought to produce these compounds on a
+commercial basis, especially by the United States government.</p>
+
+<p>After separating the potassium chloride from the magnesium chloride and
+other substances found in Stassfurt salts the methods of manufacture of
+caustic potash are identical to those of caustic soda. In this case,
+however, domestic electrolytic caustic potash may be purchased cheaper
+than the imported product and it gives results equal to those obtained
+by the use of the imported article, opinions to the contrary among soap
+makers being many. Most of the caustic potash in the United States is
+manufactured at Niagara Falls by the Niagara Alkali Co., and the Hooker
+Electrochemical Co., chlorine being obtained as a by-product. The latter
+concern employs the Townsend Cell, for the manufacture of electrolytic
+potash, and are said to have a capacity for making 64 tons of alkali
+daily.</p>
+
+<p>Since the molecular weight of caustic potash (56) is greater than that
+of caustic soda (40) more potash is required to saponify a pound of fat.
+The resulting potash soap is correspondingly heavier than a soda soap.
+When salt is added to a potassium soap double decomposition occurs, the
+potassium soap being transformed to a sodium soap and the potassium
+uniting with the chlorine to form potassium chloride. This was one of
+the earliest methods of making a hard soap, especially in Germany, where
+potash was derived from leeching ashes of burned wood and plants.<span class='pagenum'><a name="Page_28" id="Page_28">[Pg 28]</a></span></p>
+
+
+<h3>SODIUM CARBONATE (SODA ASH).</h3>
+
+<p>While carbonate of soda is widely distributed in nature the source of
+supply is entirely dependent upon the manufactured product. Its uses are
+many, but it is especially important to the soap industry in the so
+called carbonate saponification of free fatty acids, as a constituent of
+soap powders, in the neutralization of glycerine lyes and as a filler
+for laundry soaps.</p>
+
+<p>The old French Le Blanc soda process, which consists in treating common
+salt with sulphuric acid and reducing the sodium sulphate (salt cake)
+thus formed with carbon in the form of charcoal or coke to sodium
+sulphide, which when treated with calcium carbonate yields a mixture of
+calcium sulphide and sodium carbonate (black ash) from which the
+carbonate is dissolved by water, has been replaced by the more recent
+Solvay ammonia soda process. Even though there is a considerable loss of
+salt and the by-product calcium chloride produced by this process is
+only partially used up as a drying agent, and for refrigerating
+purposes, the Le Blanc process cannot compete with the Solvay process,
+so that the time is not far distant when the former will be considered a
+chemical curiosity. In the Solvay method of manufacture sodium chloride
+(common salt) and ammonium bicarbonate are mixed in solution. Double
+decomposition occurs with the formation of ammonium chloride and sodium
+bicarbonate. The latter salt is comparatively difficultly soluble in
+water and crystallizes out, the ammonium chloride remaining in solution.
+When the sodium bicarbonate is heated it yields sodium carbonate, carbon
+dioxide and water; the carbon dioxide is passed into ammonia which is
+set free from the ammonium chloride obtained as above by treatment with
+lime (calcium oxide) calcium chloride being the by-product.<span class='pagenum'><a name="Page_29" id="Page_29">[Pg 29]</a></span></p>
+
+<p>Sal soda or washing soda is obtained by recrystallizing a solution of
+soda ash in water. Large crystals of sal soda containing but 37% sodium
+carbonate are formed.</p>
+
+
+<h3>POTASSIUM CARBONATE.</h3>
+
+<p>Potassium carbonate is not extensively used in the manufacture of soap.
+It may be used in the forming of soft soaps by uniting it with free
+fatty acids. The methods of manufacture are the same as for sodium
+carbonate, although a much larger quantity of potassium carbonate than
+carbonate of soda is obtained from burned plant ashes. Purified
+potassium carbonate is known as <i>pearl ash</i>.</p>
+
+
+<h3>ADDITIONAL MATERIAL USED IN SOAP MAKING.</h3>
+
+<p>Water is indispensable to the soap manufacturer. In the soap factory
+<i>hard</i> water is often the cause of much trouble. Water, which is the
+best solvent known, in passing through the crevices of rocks dissolves
+some of the constituents of these, and the water is known as hard. This
+hardness is of two kinds, <i>temporary</i> and <i>permanent</i>. Temporarily hard
+water is formed by water, which contains carbonic acid, dissolving a
+portion of calcium carbonate or carbonate of lime. Upon boiling, the
+carbonic acid is driven from the water and the carbonate, being
+insoluble in carbon dioxide free water, is deposited. This is the cause
+of boiler scale, and to check this a small amount of sal ammoniac may be
+added to the water, which converts the carbonate into soluble calcium
+chloride and volatile ammonium carbonate. Permanent hardness is caused
+by calcium sulphate which is soluble in 400 parts of water and cannot be
+removed by boiling.</p>
+
+<p>The presence of these salts in water form insoluble lime soaps which act
+as inert bodies as far as their value for the common use of soap is
+concerned. Where the percentage of lime in water is large this should be
+removed.<span class='pagenum'><a name="Page_30" id="Page_30">[Pg 30]</a></span> A method generally used is to add about 5% of 20&deg; B. sodium
+silicate to the hard water. This precipitates the lime and the water is
+then sufficiently pure to use.</p>
+
+<p><i>Salt</i>, known as sodium chloride, is used to a large extent in soap
+making for "salting out" the soap during saponification, as well as
+graining soaps. Soap ordinarily soluble in water is insoluble in a salt
+solution, use of which is made by adding salt to the soap which goes
+into solution and throws any soap dissolved in the lyes out of solution.
+Salt may contain magnesium and calcium chlorides, which of course are
+undesirable in large amounts. The products on the market, however, are
+satisfactory, thus no detail is necessary.</p>
+
+<p><i>Filling materials</i> used are sodium silicate, or water glass, talc,
+silex, pumice, starch, borax, tripoli, etc.</p>
+
+<p>Besides these other materials are used in the refining of the oils and
+fats, and glycerine recovery, such as Fuller's earth, bichromates of
+soda or potash, sulphate of alumina, sulphuric and hydrochloric acids
+and alcohol.</p>
+
+<p>A lengthy description of these substances is not given, as their modes
+of use are detailed elsewhere.</p>
+
+<div class="footnotes"><h3>FOOTNOTES:</h3>
+
+<div class="footnote"><p><a name="Footnote_1_1" id="Footnote_1_1"></a><a href="#FNanchor_1_1"><span class="label">[1]</span></a> Seifensieder Zeit, 1913, 40, p. 687, 724, 740.</p></div>
+
+<div class="footnote"><p><a name="Footnote_2_2" id="Footnote_2_2"></a><a href="#FNanchor_2_2"><span class="label">[2]</span></a> Official Methods, see Bull. 107, A. O. A. C., U. S. Dept.
+Agricult.</p></div>
+
+<div class="footnote"><p><a name="Footnote_3_3" id="Footnote_3_3"></a><a href="#FNanchor_3_3"><span class="label">[3]</span></a> Journ. Coll. of Engin. Tokyo Imper. Univ. (1906), p. 1.
+Abs. Chem. Revue f. d. Fett-u. Harz, Ind. 16, p. 84; 20, p. 8.</p></div>
+
+<div class="footnote"><p><a name="Footnote_4_4" id="Footnote_4_4"></a><a href="#FNanchor_4_4"><span class="label">[4]</span></a> Meyerheim&mdash;Fort. der Chem., Physik. und Physik. Chem.
+(1913), 8. 6, p. 293-307.</p></div>
+
+<div class="footnote"><p><a name="Footnote_5_5" id="Footnote_5_5"></a><a href="#FNanchor_5_5"><span class="label">[5]</span></a> Seifs. Ztg. (1913), 40, p. 142.</p></div>
+
+<div class="footnote"><p><a name="Footnote_6_6" id="Footnote_6_6"></a><a href="#FNanchor_6_6"><span class="label">[6]</span></a> Loc. cit.</p></div>
+
+<div class="footnote"><p><a name="Footnote_7_7" id="Footnote_7_7"></a><a href="#FNanchor_7_7"><span class="label">[7]</span></a> Les Matieres Graisses (1914), 7, 69, p. 3367.</p></div>
+
+<div class="footnote"><p><a name="Footnote_8_8" id="Footnote_8_8"></a><a href="#FNanchor_8_8"><span class="label">[8]</span></a> Zeit. f. Angew. Chem. (1914), 27, 1, p. 2-4.</p></div>
+</div>
+
+
+<hr style="width: 65%;" /><p><span class='pagenum'><a name="Page_31" id="Page_31">[Pg 31]</a></span></p>
+<h2>CHAPTER II</h2>
+
+<h3>Construction and Equipment of a Soap Plant.</h3>
+
+
+<p>No fixed plan for the construction and equipment of a soap plant can be
+given. The specifications for a soap factory to be erected or remodeled
+must suit the particular cases. Very often a building which was
+constructed for a purpose other than soap manufacture must be adapted
+for the production of soap. In either case it is a question of
+engineering and architecture, together with the knowledge obtained in
+practice and the final decision as to the arrangement is best solved by
+a conference with those skilled in each of these branches.</p>
+
+<p>An ideal soap plant is one in which the process of soap making, from the
+melting out of the stock to the packing and shipping of the finished
+product, moves downward from floor to floor, since by this method it is
+possible to utilize gravitation rather than pumping liquid fats and
+fluid soaps. Convenience and economy are obtained by such an
+arrangement.</p>
+
+<p>The various machinery and other equipment for soap manufacture are well
+known to those connected with this industry. It varies, of course,
+depending upon the kind of soap to be manufactured, and full
+descriptions of the necessary machinery are best given in the catalogs
+issued by the manufacturers of such equipment, who in this country are
+most reliable.</p>
+
+<p>To know just what equipment is necessary can very easily be described by
+a brief outline of the process various soaps undergo to produce the
+finished article. After the saponification has taken place in the <i>soap
+kettle</i> the molten soap is run directly into the soap <i>frames</i>,<span class='pagenum'><a name="Page_32" id="Page_32">[Pg 32]</a></span> which
+consist of an oblong compartment, holding anywhere from 400 to 1,200
+pounds, with removable steel sides and mounted upon trucks, in which it
+solidifies. In most cases it is advisable to first run the soap into a
+<i>crutcher</i> or mixer which produces a more homogeneous mass than if this
+operation is omitted. Color and perfume may also be added at this point,
+although when a better grade of perfume is added it must be remembered
+that there is considerable loss due to volatilization of same. When a
+<i>drying machine</i> is employed the molten soap is run directly upon the
+rollers of this machine, later adding about 1.0% zinc oxide to the soap
+from which it passes continuously through the drying chamber and is
+emitted in chip form ready for milling. After the soap has been framed,
+it is allowed to cool and solidify, which takes several days, and then
+the sides of the frame are stripped off. The large solid cake is cut
+with wires by hand or by a <i>slabber</i> into slabs of any desired size.
+These slabs are further divided into smaller divisions by the <i>cutting
+table</i>. In non-milled soaps (laundry soaps, floating soaps, etc.), these
+are pressed at this stage, usually by automatic presses, after a thin
+hard film has been formed over the cake by allowing it to dry slightly.
+In making these soaps they are not touched by hand at any time during
+the operation, the pressing, wrapping and packing all being done by
+machinery. For a milled soap the large slabs are cut into narrow oblong
+shapes by means of the cutting table to readily pass into the feeder of
+the <i>chipper</i>, the chips being spread upon <i>trays</i> and dried in a <i>dry
+house</i> until the moisture content is approximately 15%.</p>
+
+<p>The process of milling is accomplished by passing the dried soap chips
+through a <i>soap mill</i>, which is a machine consisting of usually three or
+four contiguous, smooth,<span class='pagenum'><a name="Page_33" id="Page_33">[Pg 33]</a></span> granite rollers operated by a system of gears
+and set far enough apart to allow the soap to pass from a hopper to the
+first roller, from which it is constantly conveyed to each succeeding
+roller as a thin film, and finally scraped from the last roller to fall
+into the <i>milling box</i> in thin ribbon form. These mills are often
+operated in tandem, which necessitates less handling of soap by the
+operator. The object of milling is to give the soap a glossy, smooth
+finish and to blend it into a homogeneous mass. The perfume, color,
+medication or any other material desired are added to the dried soap
+chips prior to milling. Some manufacturers use an <i>amalgamator</i> to
+distribute these uniformly through the soap, which eliminates at least
+one milling. When a white soap is being put through the mill, it is
+advisable to add from 0.5% to 1% of a good, fine quality of zinc oxide
+to the soap, if this substance has not been previously added. This
+serves to remove the yellowish cast and any translucency occasioned by
+plodding. Too great a quantity of this compound added, later exhibits
+itself by imparting to the soap a dead white appearance. Inasmuch as the
+milling process is one upon which the appearance of a finished cake of
+toilet soap largely depends, it should be carefully done. The number of
+times a soap should be milled depends upon the character of a soap being
+worked. It should of course be the object to mill with as high a
+percentage of moisture as possible. Should the soap become too dry it is
+advisable to add water directly, rather than wet soap, since water can
+more easily be distributed through the mass. As a general statement it
+may be said it is better policy to overmill a soap, rather than not mill
+it often enough.</p>
+
+<p>After the soap has been thoroughly milled it is ready for plodding. A
+<i>plodder</i> is so constructed as to take the<span class='pagenum'><a name="Page_34" id="Page_34">[Pg 34]</a></span> soap ribbons fed into the
+hopper by means of a worm screw and continuously force it under great
+pressure through a jacketed cylinder through which cold water circulates
+in the rear to compensate the heat produced by friction and hot water at
+the front, to soften and polish the soap which passes out in solid form
+in bars of any shape and size depending upon the form of the <i>shaping
+plate</i> through which it is emitted. The bars run upon a <i>roller board</i>,
+are cut into the required length by a special <i>cake cutting table</i>,
+allowed to dry slightly and pressed either automatically or by a foot
+power <i>press</i> in any suitable soap <i>die</i>. The finished cake is then
+ready for wrapping and after due time in stock reaches the consumer.</p>
+
+<p>Besides the various apparatus mentioned above there are many other parts
+for the full equipment of a modern soap plant, such as remelters, pumps,
+mixers, special tanks, power equipment, etc. As has been stated,
+however, practical experience will aid in judging the practicability as
+to installation of these. The various methods of powdering soap are,
+however, not generally known. Where a coarse powder is to be produced,
+such as is used for common washing powders, no great difficulty is
+experienced with the well known Blanchard mill. In grinding soap to an
+impalpable powder the difficulties increase. The methods adapted in
+pulverizing soaps are by means of disintegrators, pebble mills and
+chaser mills. The disintegrator grinds by the principle of attrition,
+that is, the material is reduced by the particles being caused to beat
+against each other at great velocity; a pebble mill crushes the
+substance by rubbing it between hard pebbles in a slowly revolving
+cylinder; the chaser mill first grinds the material and then floats it
+as a very fine powder above a curb of fixed height. The last method is
+particularly adapted for the finest of powder (140 mesh and over).</p>
+
+
+
+<hr style="width: 65%;" /><p><span class='pagenum'><a name="Page_35" id="Page_35">[Pg 35]</a></span></p>
+<h2>CHAPTER III</h2>
+
+<h3>Classification of Soap-Making Methods.</h3>
+
+
+<p>In the saponification of fats and oils to form soap through the agency
+of caustic alkalis, as has been stated, the sodium or potassium salts of
+the mixed fatty acids are formed. Sodium soaps are usually termed hard
+soaps, and potassium soaps soft. There are, however, a great many
+varieties of soaps the appearance and properties of which depend upon
+their method of manufacture and the oils or fats used therein.</p>
+
+<p>The various methods adopted in soap making may be thus classified:</p>
+
+<p>1. Boiling the fats and oils in open kettles by open steam with
+indefinite quantities of caustic alkali solutions until the finished
+soap is obtained; ordinarily named <i>full boiled soaps</i>. These may be
+sub-divided into (a) hard soaps with sodium hydrate as a base, in which
+the glycerine is recovered from the spent lyes; (b) hard soaps with soda
+as a base, in which the glycerine remains in the soap, e. g., marine
+cocoanut oil soaps; (c) soft potash soaps, in which the glycerine is
+retained by the soap.</p>
+
+<p>2. Combining the required amount of lye for complete saponification of a
+fat therewith, heating slightly with dry heat and then allowing the
+saponification to complete itself. This is known as the <i>cold process</i>.</p>
+
+<p>3. Utilizing the fatty acid, instead of the neutral fat, and combining
+it directly with caustic alkali or carbonate, which is incorrectly
+termed <i>carbonate saponification</i>, since it is merely neutralizing the
+free fatty acid and thus is not a saponification in the true sense of
+the word. No glycerine is directly obtained by this method, as it is<span class='pagenum'><a name="Page_36" id="Page_36">[Pg 36]</a></span>
+usually previously removed in the clearage of the fat by either the
+Twitchell or autoclave saponification method.</p>
+
+<p>In the methods thus outlined the one most generally employed is the full
+boiled process to form a sodium soap. This method of making soap
+requires close attention and a knowledge which can only be obtained by
+constant practice. The stock, strength of lyes, heat, amount of salt or
+brine added, time of settling, etc., are all influencing factors.</p>
+
+<p>The principles involved in this process are briefly these:</p>
+
+<p>The fat is partly saponified with weak lyes (usually those obtained from
+a previous boiling in the strengthening change are used), and salt is
+added to grain the soap. The mass is then allowed to settle into two
+layers. The upper layer is partly saponified fat; the lower layer, or
+spent lye, is a solution of salt, glycerine, and contains any albuminous
+matter or any other impurity contained in the fat. This is known as the
+<i>killing</i> or glycerine change. Strong lyes are now added and the fat
+entirely saponified, which is termed the <i>strengthening change</i>. The
+mass is then allowed to settle and the fluid soap run off above the
+"nigre." This operation is called the finish or <i>finishing</i> change.</p>
+
+<p>The method may be more fully illustrated by a concrete example of the
+method of manufacture of a tallow base:</p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='right'>Charge&mdash;</td></tr>
+<tr><td align='left'>Tallow</td><td align='left'>88 per cent.</td></tr>
+<tr><td align='left'>Cocoanut oil</td><td align='left'>10 per cent.</td></tr>
+<tr><td align='left'>Rosin w. w.</td><td align='left'>2 per cent.</td></tr>
+<tr><td align='right'>Amount charge</td><td align='left'>10 tons</td></tr>
+</table></div>
+
+
+<p>About five tons of tallow and one ton of cocoanut oil are pumped or run
+into the soap kettle and brought to a boil with wet steam until it
+briskly comes through the hot fat. The caustic soda (strengthening lyes
+from former<span class='pagenum'><a name="Page_37" id="Page_37">[Pg 37]</a></span> boilings may be used here) is gradually added by the
+distributing pipe, any tendency to thicken being checked by the
+introduction of small quantities of brine ("salt pickle"). If the lye is
+added too rapidly the soap assumes a granular appearance, indicating
+that the addition of same must be discontinued. Water should then be
+added and the mass boiled through until it again closes. When the
+addition of the proper amount of caustic soda is nearing its completion
+the soap gradually thins. The steam is now cut down to about one turn of
+the valve, and brine is rapidly added or salt shoveled in. In ten to
+fifteen minutes the steam again breaks through and, from the appearance
+of the soap, it can be seen whether sufficient brine has been added. A
+sample taken out by means of a long wooden paddle should show the soap
+in fine grains with the lyes running from it clear. The steam is then
+shut off and the soap allowed to settle from one and one-half to two
+hours. In all settlings the longer time this operation is permitted to
+continue, the better will the subsequent operations proceed.</p>
+
+<p>The mixture now consists of a partly saponified layer of fat above the
+spent lyes. The lyes are drawn off until soap makes its appearance at
+the exit pipe. The valve is then closed and the soap blown back into the
+kettle by steam. The lyes thus obtained are known as <i>spent lyes</i>, from
+which the glycerine is recovered. They should show an alkalinity of
+approximately 0.5 per cent. if the operation is carefully carried out.</p>
+
+<p>The remaining tallow is now added and the above operations repeated.</p>
+
+<p>After the spent lyes have been drawn off, the soap is closed with water
+and the proper percentage of rosin soap previously formed, or rosin
+itself is added to the mass in the kettle. More lye is then allowed to
+flow in until the<span class='pagenum'><a name="Page_38" id="Page_38">[Pg 38]</a></span> mixture is up to "strength." This is usually tested
+by the "bite" on the tongue of a small cooled sample. After boiling
+until the steam comes through, the mass is grained with salt as before
+and allowed to settle one and one-half to three hours. These lyes, known
+as <i>strengthening lyes</i> are run to storage to be used subsequently with
+fresh fat to take up the caustic soda contained therein.</p>
+
+<p>The soap is now ready for finishing and is first boiled through and
+tried for strength. A drop of phenolphthalein (1 per cent.
+phenolphthalein in 98 per cent. alcohol) is allowed to drop on the
+molten soap taken up on a trowel. The red color should be instantly
+produced and develop to a full deep crimson in a few seconds, or more
+lye must be added until this condition is realized. Should it flash a
+deep crimson immediately it is on the strong side. This cannot be
+conveniently remedied; it can only serve as a guide for the next boil,
+but in any case it is not of any serious consequence, unless it is too
+strong.</p>
+
+<p>With the steam on, the soap is now examined with a trowel which must be
+thoroughly heated by working it about under the surface of the hot soap.
+The appearance of the soap as it runs from the face of the trowel
+indicates its condition. It is not possible to absolutely describe the
+effect, which can only be properly judged by practice, yet the following
+points may serve as a guide. The indications to be noticed are the shape
+and size of the flakes of soap as the sample on the trowel breaks up and
+runs from the hot iron surface, when the latter is turned in a vertical
+position, as well as the condition of the iron surface from which the
+soap flakes have fallen. A closed soap will run slowly into a
+homogeneous sheet, leaving the trowel's surface covered with a thin
+layer of transparent soap; a grained mass will run rapidly down in tiny
+grains, about one-half an inch in diameter or less, leaving the hot
+trowel<span class='pagenum'><a name="Page_39" id="Page_39">[Pg 39]</a></span> absolutely dry. The object of the finish is to separate the
+soaps of the lower fatty acids from those of the higher, and both from
+excess of liquid. A point midway between "open" and "closed" is required
+to arrive at this point.</p>
+
+<p>Having arrived at the above condition, the soap is allowed to settle
+anywhere from one to three days and then run off through the skimmer
+pipes to the nigre and framed or pumped to the tank feeding the drying
+machine.</p>
+
+<p>The stock thus obtained should be fairly white, depending upon the grade
+of tallow used and slightly alkaline to an alcoholic phenolphthalein
+solution. If removed at exactly the neutral point or with a content of
+free fat the soap will sooner or later develop rancidity. The soap thus
+obtained is an ordinary tallow base, and the one by far greatest used in
+the manufacture of toilet soaps. The percentage of cocoanut oil
+indicated is not fixed and may readily be varied, while in fine toilet
+soap the rosin is usually eliminated.</p>
+
+<p>In the manufacture of full boiled soda soaps in which no glycerine is
+obtained as a by-product, it being retained in the soap itself, the soap
+formed is known as a "run" soap. The process is used most extensively in
+the manufacture of marine soaps by which the method may be best
+illustrated. This soap is known as marine soap because of its property
+of readily forming a lather with salt water and is mostly consumed
+aboard vessels.</p>
+
+<p>Marine soaps are manufactured by first placing in the kettle a
+calculated amount of lye of 25 deg. to 35 deg. B., depending upon the
+amount of moisture desired in the finished soaps, plus a slight excess
+required to saponify a known weight of cocoanut oil. With open steam on,
+the cocoanut oil is then gradually added, care being taken that the soap
+does not froth over. Saponification takes place readily and when the oil
+is entirely saponified the finished<span class='pagenum'><a name="Page_40" id="Page_40">[Pg 40]</a></span> soap is put through the process
+known as running. This consists in constantly pumping the mass from the
+skimmer pipe back into the top of the kettle, the object being to
+prevent any settling of the nigre or lye from the soap, as well as
+producing a homogeneous mass. It is customary to begin the
+saponification in the morning, which should be completed by noon. The
+soap is then run for about three hours and framed the next morning.
+After having remained in the frame the time required to solidify and
+cool, the soap is slabbed and cut into cakes. This process is difficult
+to carry out properly, and one not greatly employed, although large
+quantities of marine soap are purchased by the government for use in the
+navy and must fulfill certain specifications required by the purchasing
+department.</p>
+
+<p>In making potash soaps it is practically impossible to obtain any
+glycerine directly because of the pasty consistency of the soap, and no
+graining is possible because the addition of salt to a soft soap, as
+already explained, would form a soda soap. Large quantities of soft
+soaps are required for the textile industries who desire mostly a strong
+potash soap, and the large number of automobiles in use at the present
+time has opened a field for the use of a soft soap for washing these. A
+soap for this purpose must be neutral so as not to affect the varnish or
+paint of automobiles.</p>
+
+<p>A suitable soap for textile purposes may be made as follows:</p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Red oil</td><td align='left'>80</td><td align='left'>parts</td></tr>
+<tr><td align='left'>House grease</td><td align='left'>20</td><td align='left'>parts</td></tr>
+<tr><td align='left'>Caustic soda lye, 36 degs. B.</td><td align='left'>&nbsp;3</td><td align='left'>parts</td></tr>
+<tr><td align='left'>Carbonate of potash</td><td align='left'>&nbsp;5-1/2</td><td align='left'>parts</td></tr>
+<tr><td align='left'>Caustic potash</td><td align='left'>23-1/4</td><td align='left'>parts</td></tr>
+</table></div>
+
+
+<p>Olive oil, corn oil, soya bean oil, olive oil foots or cottonseed<span class='pagenum'><a name="Page_41" id="Page_41">[Pg 41]</a></span> oil
+may replace any of the above oils. A large quantity of cottonseed oil
+will cause the soap to fig.</p>
+
+<p>To carry out the process, the caustic potash and carbonate of potash are
+dissolved and placed in the kettle together with the soda lye, and the
+oils added. This is most satisfactorily accomplished by being finished
+the day before the boiling is begun. The next day the boiling is begun
+and water added to bring the soap up to the desired percentage of fatty
+acid, due allowance being made for the water formed by the condensation
+of the open steam in boiling. Care must be taken that the soap in the
+kettle does not swell and run over during the saponification. A good
+procedure is to use open steam for a period of about two hours, then
+close the valve and allow the saponification to continue without
+boiling, and repeat this until it is entirely saponified. After the
+saponification has been completed the soap is briskly boiled all day and
+the proper corrections made; that is, if too alkaline, more oil is
+added, and if free fat is present, more potash. About 2 per cent.
+carbonate of potash is the proper amount for a soap containing 50 per
+cent. fatty acid. The soap is sampled by allowing it to drop on a clean,
+cold glass surface. In so doing, the soap should not slide or slip over
+the glass surface when pressed thereon, but should adhere to the glass,
+or it is too alkaline. A sample worked between the fingers showing too
+much stringiness should have more strong potash and oil added. A sample
+taken out in a pail and allowed to cool over night will serve as a guide
+as to the body of the soap in the kettle. When the soap has thus been
+properly finished it is run into barrels.</p>
+
+<p>For an automobile soap the following is a good working formula:</p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Corn oil</td><td align='right'>1,000</td><td align='left'>parts</td></tr>
+<tr><td align='left'>Potash lye, 31-1/2 degs. B.</td><td align='right'>697</td><td align='left'>parts</td></tr>
+</table></div>
+
+
+<p><span class='pagenum'><a name="Page_42" id="Page_42">[Pg 42]</a></span></p>
+
+<p>Proceed as in the directions just given for textile soap in placing
+charge in the kettle. When the kettle is boiling up well, shut off the
+steam and the saponification will complete itself. The soap may be run
+into the barrels the next day.</p>
+
+<p>A heavy soap with a smaller percentage of fat may be made as follows:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Corn oil</td><td align='right'>1,000</td><td align='left'>parts</td></tr>
+<tr><td align='left'>Potash lye, 24-1/2 degs. B.</td><td align='right'>900</td><td align='left'>parts</td></tr>
+</table></div>
+
+<p>Boil until the soap bunches, and shovel the finished soap into barrels.
+Upon standing it will clear up. By the addition of more water the yield
+of soap per pound of oil may be run up to 300 per cent.</p>
+
+<p>After soft soaps have been allowed to stand for some time the phenomenon
+known as "figging" often occurs. This term is applied to a
+crystalline-like formation, causing spots of a star-like shape
+throughout the soap. This is undoubtedly due to the stearine content of
+the soap crystallizing out as it cools, and forming these
+peculiarly-shaped spots. It more generally occurs in the winter and may
+be produced artificially by adding a small quantity of soda to the
+potash lye before saponification.</p>
+
+<p>The oils usually employed in the manufacture of potash soaps are
+cottonseed oil, corn oil, soya bean oil, olive oil foots, red oil,
+cocoanut oil, grease and the various train oils. The usual percentage
+yield is from 225 per cent. to 300 per cent., based upon the weight of
+oil used. In calculating the weight of a soft soap it is to be
+remembered that since potassium has a higher molecular weight (56) than
+sodium (40), the corresponding soap formed is that much greater in
+weight when compared with a sodium soap. Rosin may be added to soft
+soaps as a cheapening agent.<span class='pagenum'><a name="Page_43" id="Page_43">[Pg 43]</a></span></p>
+
+
+<h3>COLD PROCESS.</h3>
+
+<p>The cold process for manufacturing soap is the simplest method of soap
+making, and the equipment required is small when compared to the other
+methods. All the more expensive equipment that is necessary is a
+crutcher, a tank to hold the lye, frames, a slabber or cutting table,
+and a press. Yet, in spite of the simplicity of thus making soap, the
+disadvantages are numerous for the production of a good piece of soap.
+The greatest difficulty is to obtain a thorough combination of oil or
+fat and lye so that there will not be an excess of one or the other in
+the finished soap. At its best there is either a considerable excess of
+free fat which later exhibits itself in producing rancidity or
+uncombined caustic, which produces an unpleasant effect on the skin when
+the soap is consumed for washing. The latter objection, of course, can
+only be applied to toilet soaps.</p>
+
+<p>Cocoanut oil is used very largely in the manufacture of cold-made soaps
+as it is well adapted for this purpose, although it is by no means true
+that other oils may not be employed. Since by this process of
+manufacture no impurity contained in the fat or oil is removed in the
+making of the soap, it is necessary that in order to obtain a fine
+finished product, any impurity contained in these may be removed if
+present, or that the fats be as pure as can be obtained. If inedible
+tallow is used for cold-made soap, it is advisable to bleach it by the
+Fuller's Earth Process.</p>
+
+<p>The carrying out of this method is best illustrated by an example of a
+cold-made cocoanut oil soap.</p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='right'>Charge:</td></tr>
+<tr><td align='left'>Cochin cocoanut oil</td><td align='right'>846</td><td align='left'>parts</td></tr>
+<tr><td align='left'>Lye (soda), 35 degs. B.</td><td align='right'>470</td><td align='left'>parts</td></tr>
+<tr><td align='left'>Water</td><td align='right'>24</td><td align='left'>parts</td></tr>
+</table></div>
+
+
+<p><span class='pagenum'><a name="Page_44" id="Page_44">[Pg 44]</a></span></p>
+
+<p>The oil is run into the crutcher and the temperature of the oil raised
+to 100 degs. F. by dry steam. The lye and water are at room temperature.
+After all the oil is in the crutcher, the lye and water are slowly added
+to prevent any graining of the soap. Toward the end the lye may be added
+more rapidly. When all the lye is in, the mass is crutched for about
+three hours, or until upon stopping the crutcher a finger drawn over the
+surface of the soap leaves an impression. If this condition is not
+realized, the soap must be mixed until such is the case. Having arrived
+at this point, the mixture is dropped into a frame which should remain
+uncovered. The heat produced by the further spontaneous saponification
+will cause the soap to rise in the middle of the frame. After having set
+for some days it is ready to be slabbed and cut into cakes.</p>
+
+<p>A potash soap may be made by the cold process just as readily as a soda
+soap. Soaps of this type may be made by either of these formulae in a
+crutcher:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Olive oil foots</td><td align='right'>600</td></tr>
+<tr><td align='left'>Potash lye, 18 degs. B. hot, 20 degs. B. cold</td><td align='right'>660</td></tr>
+</table></div>
+
+<p class="center">or</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Corn oil</td><td align='right'>800</td></tr>
+<tr><td align='left'>Rosin</td><td align='right'>200</td></tr>
+<tr><td align='left'>Potash lye, 27 degs. B.</td><td align='right'>790</td></tr>
+<tr><td align='left'>Water</td><td align='right'>340</td></tr>
+</table></div>
+
+
+<p>Heat the oils to 190 degs. F., add the lye and crutch until the soap
+begins to bunch, when it is ready to be run into barrels where the
+saponification will be completed.</p>
+
+<p>Semi-boiled soaps differ from those made by the cold process in
+temperature. In making semi-boiled soaps the fats are usually heated to
+140&deg; F. The addition of the<span class='pagenum'><a name="Page_45" id="Page_45">[Pg 45]</a></span> lye raises the temperature to 180&deg;&mdash;200&deg; F.
+when saponification takes place.</p>
+
+
+<h3>CARBONATE SAPONIFICATION.</h3>
+
+<p>The method of the formation of soap by the utilization of the fatty acid
+directly, from which the glycerine has already been removed by some
+method of saponification other than with caustic soda, and neutralizing
+this with alkali, is becoming increasingly popular. The glycerine is
+more easily recovered from a previous cleavage of the fats or oils, but
+a soap made from the mixed fatty acids thus obtained is seldom white in
+color and retains an unpleasant odor. Since soda ash or sodium carbonate
+is cheaper than caustic soda and readily unites with a fatty acid, it is
+used as the alkali in the carbonate saponification. The process is
+similar to that already given under Rosin Saponification. About 19 per
+cent. by weight of the fatty acids employed of 58 per cent. soda ash is
+dissolved in water until it has a density of 30 degs. B., and the
+solution is run into the kettle, which is usually equipped with a
+removable agitator. The fatty acids, previously melted, are then slowly
+added while the mixture is boiled with open steam and agitated with the
+stirring device. The fatty acids instantly unite with the carbonate and
+rise in the kettle, due to the generation of carbon dioxide, and care
+must be exercised to prevent boiling over. After all the fatty acid has
+been added, and the mass is boiled through the saponification must be
+completed with caustic soda, as there is as yet no practical method
+known which will split a fat entirely into fatty acid and glycerine.
+Thus about 10 per cent. of the fatty acids are true neutral fats and
+require caustic soda for their saponification. This is then added and
+the soap completed, as in full-boiled soaps.</p>
+
+<p>In carrying out this method upon a large scale, large<span class='pagenum'><a name="Page_46" id="Page_46">[Pg 46]</a></span>
+sue\Neanderthal\doroteer\Neanderthal\Josephine\ quantities of carbon
+dioxide are formed during the boiling of the soap, which replaces a
+quantity of the air contained therein. The kettle room should therefore
+be well ventilated, allowing for a large inflow of fresh air from out of
+doors.</p>
+
+
+
+<hr style="width: 65%;" /><p><span class='pagenum'><a name="Page_47" id="Page_47">[Pg 47]</a></span></p>
+<h2>CHAPTER IV</h2>
+
+<h3>Classification of Soaps.</h3>
+
+
+<p>In considering the many different varieties of soaps, their
+classification is purely an arbitrary one. No definite plan can be
+outlined for any particular brand to be manufactured nor can any very
+sharp distinction be drawn between the many soaps of different
+properties which are designated by various names. It is really a
+question to what use a soap is to be put, and at what price it may be
+sold. There is, of course, a difference in the appearance, form and
+color, and then there are soaps of special kinds, such as floating
+soaps, transparent soaps, liquid soaps, etc., yet in the ultimate sense
+they are closely allied, because they are all the same chemical
+compound, varying only in their being a potash or soda soap, and in the
+fatty acids which enter into combination with these alkalis. Thus we can
+take a combination of tallow and cocoanut oil and make a great many
+presumably different soaps by combining these substances with caustic
+soda, by different methods of manufacture and by incorporating various
+other ingredients, as air, to form a floating soap, alcohol to make a
+transparent soap, dyestuffs to give a different color, etc., but
+essentially it is the same definite compound.</p>
+
+<p>The manufacturer can best judge the brand of soaps he desires to
+manufacture, and much of his success depends upon the name, package,
+shape, color or perfume of a cake of soap. It is the consumer whom he
+must please and many of the large selling brands upon the market today
+owe their success to the above mentioned details. The great majority of
+consumers of soap know very little<span class='pagenum'><a name="Page_48" id="Page_48">[Pg 48]</a></span> concerning soap, except the fact
+that it washes or has a pleasant odor or looks pretty, and the
+manufacturer of soap must study these phases of the subject even more
+carefully than the making of the soap itself.</p>
+
+<p>For a matter of convenience we will classify soap under three general
+divisions:</p>
+
+<p>I. Laundry soaps, including chip soaps, soap powders and scouring soaps.</p>
+
+<p>II. Toilet soaps, including floating soap, castile soap, liquid soap,
+shaving soap, etc.</p>
+
+<p>III. Textile soaps.</p>
+
+
+<h3>LAUNDRY SOAP.</h3>
+
+<p>The most popular household soap is laundry soap. A tremendous amount of
+this soap is consumed each day in this country, and it is by far
+manufactured in larger quantities than any other soap. It is also a soap
+which must be sold cheaper than any other soap that enters the home.</p>
+
+<p>The consumers of laundry soap have been educated to use a full boiled
+settled rosin soap and to make a good article at a price this method
+should be carried out, as it is the one most advisable to use. The
+composition of the fats entering into the soap depends upon the market
+price of these, and it is not advisable to keep to one formula in the
+manufacture of laundry soap, but rather to adjust the various fatty
+ingredients to obtain the desired results with the cheapest material
+that can be purchased. It is impossible to use a good grade of fats and
+make a profit upon laundry soap at the price at which it must be
+retailed. The manufacturer of this grade of soap must look to the
+by-product, glycerine, for his profit and he is fortunate indeed if he
+realizes the entire benefit of this and still produces a superior piece
+of laundry soap.<span class='pagenum'><a name="Page_49" id="Page_49">[Pg 49]</a></span></p>
+
+
+<h3>SEMI-BOILED LAUNDRY SOAPS.</h3>
+
+<p>It is advantageous at times to make a laundry soap by a method other
+than the full boiled settled soap procedure as previously outlined. This
+is especially the condition in making a naphtha soap, in which is
+incorporated naphtha, which is very volatile and some of the well known
+manufacturers of this class of soap have adopted this process entirely.
+A laundry soap containing rosin cannot be advantageously made by the
+cold process, as the soap thus made grains during saponification and
+drops a portion of the lye and filling materials. By making a
+semi-boiled soap this objection is overcome. The half boiled process
+differs from the cold process by uniting the fats and alkalis at a
+higher temperature.</p>
+
+<p>To carry out this process the following formulae have been found by
+experience to give satisfactory results.</p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='center'>I.</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>100</td></tr>
+<tr><td align='left'>Rosin</td><td align='right'>60</td></tr>
+<tr><td align='left'>Soda Lye, 36&deg; B.</td><td align='right'>80</td></tr>
+<tr><td colspan="2">II.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>100</td></tr>
+<tr><td align='left'>Rosin</td><td align='right'>60</td></tr>
+<tr><td align='left'>Silicate of Soda</td><td align='right'>25</td></tr>
+<tr><td align='left'>Soda Lye, 36&deg; B.</td><td align='right'>85</td></tr>
+<tr><td colspan="2">III.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>100</td></tr>
+<tr><td align='left'>Rosin</td><td align='right'>100</td></tr>
+<tr><td align='left'>Lye, 36&deg; B.</td><td align='right'>105</td></tr>
+<tr><td align='left'>Silicate of Soda</td><td align='right'>25</td></tr>
+<tr><td align='left'>Sal Soda Solution</td><td align='right'>20</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_50" id="Page_50">[Pg 50]</a></span></p>
+
+<p>In any of these formulas the sodium silicate (40&deg; B.) may be increased
+to the same proportion as the fats used. By so doing, however, twenty
+pounds of 36&deg; B. lye must be added for every hundred pounds of silicate
+additional to that indicated or in other words, for every pound of
+silicate added 20 per cent. by weight of 36&deg; B. lye must be put into the
+mixture. The rosin may also be replaced by a previously made rosin soap.</p>
+
+<p>To make a semi-boiled soap, using any of the above formulae, first melt
+the rosin with all or part of the fat, as rosin when melted alone
+readily decomposes. When the mixture is at 150&deg; F. run it into the
+crutcher and add the lye. Turn on sufficient dry steam to keep the
+temperature of the soap at about 150&deg; F. in the winter or 130&deg; F. in
+summer. After the mass has been mixed for half an hour, by continuously
+crutching the soap it will at first thicken, then grain and it may again
+become thick before it becomes smooth. When the mass is perfectly smooth
+and homogeneous drop into a frame and crutch in the frame by hand to
+prevent streaking. After standing the required length of time the soap
+is finished into cakes as usual.</p>
+
+
+<h3>SETTLED ROSIN SOAP.</h3>
+
+<p>Settled rosin soaps are made from tallow, grease, cottonseed oil,
+bleached palm oils of the lower grades, corn oil, soya bean oil, arachis
+oil, distilled garbage grease, cottonseed foots or fatty acids together
+with an addition of rosin, varying from 24 per cent. to 60 per cent. of
+the fatty acids which should titer from 28 to 35. A titer lower than 28
+will prevent the finished kettle of soap from being capable of later
+taking up the filling materials. As has already been stated under
+hardened oils, these being very much higher in titer allow a greater
+percentage of rosin to be added. Thus hardened fish oils and cottonseed
+oil are <span class='pagenum'><a name="Page_51" id="Page_51">[Pg 51]</a></span>gradually being more extensively employed in soaps of this
+character.</p>
+
+<p>The procedure of handling the kettle is similar to that given under full
+boiled soap. The stock is steamed out into a settling tank and allowed
+to settle over night, after which it is pumped into the soap kettle.
+Having stocked the kettle, open steam is turned on and 10&deg;-12&deg; B. lye is
+run in, while using a steam pressure of ninety to one hundred pounds in
+order to prevent too great a quantity of condensation of the steam, the
+water thus being formed weakening the lye. If a steam pressure of fifty
+to sixty pounds is available, a stronger lye (20&deg; B.) should be added.
+Care must be taken not to allow the lye to flow in too rapidly or the
+soap will not grain. The saponification is only attained by prolonged
+boiling with sufficient lye of proper strength. When saponification has
+taken place, the mass begins to clear and a sample taken out with a
+paddle and cooled should show a slight pink with a 1 per cent. alcoholic
+phenolphthalein solution.</p>
+
+<p>It may be stated here that in using this indicator or any other to test
+the alkalinity of soap, the soap should always be cooled and firm, as
+whenever water is present, the dissociation of the soap thereby will
+always react alkaline. When this state is reached the mass is ready for
+graining, which is accomplished by distributing salt brine or pickle or
+spreading dry salt over the surface of the soap. The kettle is then
+thoroughly boiled until the mass shows a soft curd and the lye drops
+clearly from a sample taken out with a trowel or paddle. The steam is
+then shut off and the soap allowed to settle over night. The lyes are
+then run off to the spent lye tank for glycerine recovery. In
+saponifying a freshly stocked kettle it is apt to bunch. To prevent this
+salt is added at various times to approximately one per cent. of the fat
+used.<span class='pagenum'><a name="Page_52" id="Page_52">[Pg 52]</a></span></p>
+
+<p>If, by any possibility the soap has bunched, this condition may be
+remedied by the addition of more strong lye and boiling until it is
+taken up. To work a kettle to its full capacity it is advisable to make
+two "killing" changes. First add about 75 per cent. of the fat and grain
+as directed. Run off the spent lyes and then add the remainder of the
+stock and repeat the process. When the spent lye has been run to
+storage, the open steam is again turned on and 18&deg; B. lye gradually
+allowed to run in. The rosin is now broken up and put into the kettle,
+or a previously made rosin soap is pumped in.</p>
+
+<p>Lye is then added until the soap has a sharp taste after about three
+hours of continuous boiling, or when the soap is in the closed state.
+More lye should then be run into the kettle to grain the soap well, the
+grain not being too small. Then allow the soap to settle over night and
+draw off the strengthening lye. The next day again boil up the kettle
+and add water until the soap thins out and rises or swells high in the
+kettle. A sample taken out at this stage upon a hot trowel should run
+off in large flakes. The surface of the soap should be bright and shiny.</p>
+
+<p>If the sample clings to the trowel, a slight addition of lye will remedy
+this defect. The kettle is then allowed to rest, to drop the nigre and
+to cool for some time, depending upon the size of the kettle. The proper
+temperature is such that after having been pumped to the crutcher and
+the filling materials having been added, a thermometer placed into the
+mass should indicate 128&deg;-135&deg; F. after the crutcher has run from ten to
+fifteen minutes. The filling material may consist of from 7-9 per cent.
+of sal soda solution, 36&deg;-37&deg; B. warm or just enough to close up the
+soap and make it rise high in the center of a screw crutcher and make it
+cling close to a warm trowel. Other fillers such as outlined below are
+added at this point.<span class='pagenum'><a name="Page_53" id="Page_53">[Pg 53]</a></span></p>
+
+<p>An addition of from 2-3 per cent. of a special mineral oil for this
+purpose will impart a finish to the soap and 3-5 per cent. starch added
+prevents the soap from cracking in the frames. Other filling material as
+silicate of soda, borax, talc or silex are used. After the filling
+material has been thoroughly crutched through the soap it is framed,
+and, after being several days in the frame to solidify and cool the soap
+is ready for slabbing, pressing and wrapping.</p>
+
+<p>In order to more definitely illustrate the composition of the mixture of
+fats and oils entering into the formation of a laundry soap a typical
+formula may be given for such a soap containing 40 per cent. rosin added
+to the amount of fats used:</p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'></td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Grease</td><td align='right'>7,000</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>4,000</td></tr>
+<tr><td align='left'>Corn Oil</td><td align='right'>7,000</td></tr>
+<tr><td align='left'>Cottonseed Oil</td><td align='right'>3,000</td></tr>
+<tr><td align='left'>Rosin</td><td align='right'>8,400</td></tr>
+</table></div>
+
+
+<p>The following have been found to be satisfactory filling materials and
+are calculated upon the basis of a 1,400-pound frame of soap.</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='center'>I.</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Sodium Silicate, 38&deg;-40&deg; B.</td><td align='right'>100</td></tr>
+<tr><td align='left'>Mineral Oil</td><td align='right'>25</td></tr>
+<tr><td align='left'>Sal Soda Solution, 36&deg; B.</td><td align='right'>80</td></tr>
+<tr><td align='left'>Borax</td><td align='right'>1</td></tr>
+<tr><td colspan="2">II.</td></tr>
+<tr><td align='left'>Sal Soda Solution, 36&deg; B.</td><td align='right'>80</td></tr>
+<tr><td align='left'>Mineral Oil</td><td align='right'>25</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='right'>60</td></tr>
+<tr><td align='left'><span class='pagenum'><a name="Page_54" id="Page_54">[Pg 54]</a></span></td></tr>
+<tr><td colspan="2">III.</td></tr>
+<tr><td align='left'>Soda Ash</td><td align='right'>10</td></tr>
+<tr><td align='left'>Sal Soda</td><td align='right'>55</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='right'>115</td></tr>
+<tr><td align='left'>Mineral Oil</td><td align='right'>40</td></tr>
+<tr><td align='left'>Brine (Saturated Solution)</td><td align='right'>10</td></tr>
+<tr><td align='left'>Sodium Silicate, 38&deg;-40&deg; B.</td><td align='right'>100</td></tr>
+<tr><td colspan="2">IV.</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='right'>100</td></tr>
+<tr><td align='left'>Silex or Talc</td><td align='right'>200</td></tr>
+<tr><td align='left'>Soda Ash</td><td align='right'>50</td></tr>
+<tr><td colspan="2">V.</td></tr>
+<tr><td align='left'>Sal Soda Solution, 36&deg; B.</td><td align='right'>90</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='right'>50-60</td></tr>
+<tr><td align='left'>Mineral Oil</td><td align='right'>25</td></tr>
+<tr><td align='left'>Borax Solution, 25&deg; B. (hot)</td><td align='right'>15</td></tr>
+</table></div>
+
+
+<h3>CHIP SOAP.</h3>
+
+<p>Chip soap is used extensively in laundries but is also used largely in
+other branches. It may be made either as a settled soap or by the cold
+made process.</p>
+
+<p>To make a full boiled settled chip soap, proceed as directed under
+settled laundry soap. The kettle is stocked with light grease or a
+mixture of grease with corn oil or other cheap oils. For this kind of
+soap the rosin is eliminated.</p>
+
+<p>Chip soap may be filled as well as laundry soap. This is done in the
+crutcher and the following adulterations are suitable.</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'></td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Settled Soap</td><td align='right'>700</td></tr>
+<tr><td align='left'>Soda Ash</td><td align='right'>35</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='right'>215</td></tr>
+<tr><td colspan="2">or</td></tr>
+<tr><td align='left'>Settled Soap</td><td align='right'>700</td></tr>
+<tr><td align='left'><span class='pagenum'><a name="Page_55" id="Page_55">[Pg 55]</a></span></td></tr>
+<tr><td align='left'>Silicate of Soda</td><td align='right'>560</td></tr>
+<tr><td align='left'>Soda Ash</td><td align='right'>18</td></tr>
+<tr><td align='left'>Carbonate of Potash, 26&deg; B.</td><td align='right'>50</td></tr>
+</table></div>
+
+<p>The cheapest method of drying is by running this soap through a drying
+machine and this is the procedure usually carried out for making dried
+chip soap.</p>
+
+
+<h3>COLD MADE CHIP SOAPS.</h3>
+
+<p>To make chip soaps by the cold process a sweet tallow of low percentage
+of free fatty acid should be employed. The tallow is heated to 120&deg; to
+135&deg; F. and the lye run in slowly at first and then the silicate of soda
+is added. The mass is then mixed until a finger drawn through the soap
+leaves a slight impression, then dropped into frames or barrels. Soaps
+containing a small percentage of fat should be well covered in the frame
+for twenty-four hours to retain their heat and insure proper
+saponification. The following formulae are suitable:</p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='center'>I.</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>1,200</td></tr>
+<tr><td align='left'>Soda Lye, 35&deg; B.</td><td align='right'>850</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='right'>750</td></tr>
+<tr><td colspan="2">II.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>475</td></tr>
+<tr><td align='left'>Ceylon Cocoanut Oil</td><td align='right'>100</td></tr>
+<tr><td align='left'>Soda Lye, 37&deg; B.</td><td align='right'>325</td></tr>
+<tr><td align='left'>Potash Lye, 37&deg; B.</td><td align='right'>56</td></tr>
+<tr><td colspan="2">III.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>500</td></tr>
+<tr><td align='left'>Soda Lye, 37-1/2&deg; B.</td><td align='right'>297</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='right'>416</td></tr>
+<tr><td align='left'>Potash Lye, 37-1/2&deg; B.</td><td align='right'>37-1/2</td></tr>
+<tr><td align='left'><span class='pagenum'><a name="Page_56" id="Page_56">[Pg 56]</a></span></td></tr>
+<tr><td colspan="2">IV.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>450</td></tr>
+<tr><td align='left'>Soda Lye, 37-1/2&deg; B.</td><td align='right'>255</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='right'>450</td></tr>
+<tr><td align='left'>Potash Lye, 37-1/2&deg; B.</td><td align='right'>50</td></tr>
+<tr><td align='left'>V.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>450</td></tr>
+<tr><td align='left'>Soda Lye, 35&deg; B.</td><td align='right'>470</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='right'>650</td></tr>
+<tr><td colspan="2">VI.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>420</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='right'>600</td></tr>
+<tr><td align='left'>Soda Lye, 37-12&deg; B.</td><td align='right'>270</td></tr>
+</table></div>
+
+
+<h3>UNFILLED CHIP SOAP.</h3>
+
+<p>A very good grade of chip soap is made by employing no filling material
+whatsoever, but unfortunately the price of this soap has been cut to
+such an extent that these can not compete with a filled chip. A number
+of the best soaps of this kind are made from a settled soap using a
+light grease with corn oil. A soap of this nature is made as follows.</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'></td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Settled Soap</td><td align='right'>800</td></tr>
+<tr><td align='left'>Sal Soda Solution, 36&deg;-37&deg; B.</td><td align='right'>252</td></tr>
+<tr><td align='left'>Soda Ash</td><td align='right'>182</td></tr>
+</table></div>
+
+<p>If this soap is run into frames it may be stripped and chipped in two
+days.</p>
+
+
+<h3>SOAP POWDERS.</h3>
+
+<p>Soap powders have become so great a convenience as a general cleansing
+agent that to eliminate them from the household necessities would mean
+much unnecessary<span class='pagenum'><a name="Page_57" id="Page_57">[Pg 57]</a></span> energy and work to the great number of consumers of
+this product. They may be manufactured so cheaply and still be
+efficient, that their use has almost become universal for cleansing and
+scouring purposes. The uses to which soap and scouring powders are
+adapted are too well known to enter into a description of their
+employment. Since they offer a greater profit to the manufacturer than
+ordinary household soap, many brands are extensively advertised.</p>
+
+<p>Numerous combinations for soap powders might be cited and it is a simple
+matter to vary the ingredients as to fat content and manufacture a
+powder of this sort as low as a cent a pound. Many substances are
+incorporated with soap, such as salt, soda ash, tripoli, crushed
+volcanic deposits, ground feldspar, infusorial earth of various kinds,
+silex, etc. In addition to these various fillers, compounds with true
+cleansing and bleaching properties, in addition to soap, are added, such
+as the salts of ammonium (sal ammoniac, carbonate of ammonia), sodium
+perborate and the peroxides of various metals. The public, however, have
+been accustomed to receive a large package of soap or scouring powder
+for a small amount of money and it is a difficult matter for the
+manufacturer to add more expensive substances of this nature to his
+product, to increase its efficiency, without raising the price or
+decreasing the size of the package.</p>
+
+<p>In manufacturing soap powders, the dried soap chips might be mixed with
+the filler and alkali and then pulverized. This method is not
+extensively employed nevertheless. The process which is the most
+economical is one whereby the ingredients are mixed in a specially
+adapted mixer for heavy material until dry and then run directly to the
+crusher and pulverizer, after which it is automatically packed, sealed
+and boxed.<span class='pagenum'><a name="Page_58" id="Page_58">[Pg 58]</a></span> Another method of procedure is to run out the mixture from
+the crutcher to the frames, which are stripped before the soap cools,
+and is cut up at once, for if it hardens it could not be cut with wires.
+It is better, however, to run the mixture into sheets upon a specially
+constructed floor and break up the mass when cool.</p>
+
+<p>Formulae for soap powders which have been found to be suitable for
+running dry in the mixer follow:</p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td colspan="2">I</td></tr>
+<tr><td align='left'>Soda ash, 58 per cent.</td><td align='right'>42</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Silica</td><td align='right'>220</td><td align='center'>"</td></tr>
+<tr><td align='left'>Settled soap (usually cottonseed).</td><td align='right'>25</td><td align='center'>"</td></tr>
+<tr><td align='left'>Salt</td><td align='right'>10</td><td align='center'>"</td></tr>
+<tr><td colspan="2">II</td></tr>
+<tr><td align='left'>Soap (settled cottonseed)</td><td align='right'>40</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Soda ash, 58 per cent.</td><td align='right'>60</td><td align='center'>"</td></tr>
+<tr><td colspan="2">III</td></tr>
+<tr><td align='left'>Settled soap</td><td align='right'>100</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Soda ash, 58 per cent.</td><td align='right'>400</td><td align='center'>"</td></tr>
+</table></div>
+
+<p>Fillers in varying proportions may replace the soda ash in the above
+formulae. It is of course understood that the soap has been previously
+made and run as molten soap into the crutcher.</p>
+
+<p>The following soap powders will not dry up in the crutcher upon running,
+but are of the class which may be framed or run on the floor to
+solidify:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td colspan="2">I</td></tr>
+<tr><td align='left'>Soap</td><td align='left'>850</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Filler</td><td align='right'>400</td><td align='center'>"</td></tr>
+<tr><td align='left'>Sal soda solution, 20 degs. B</td><td align='right'>170</td><td align='center'>"</td></tr>
+<tr><td align='left'><span class='pagenum'><a name="Page_59" id="Page_59">[Pg 59]</a></span></td></tr>
+<tr><td colspan="2">II</td></tr>
+<tr><td align='left'>Soap</td><td align='right'>650</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Filler</td><td align='right'>550</td><td align='center'>"</td></tr>
+<tr><td align='left'>Sal soda solution, 20 degs. B.</td><td align='right'>340</td><td align='center'>"</td></tr>
+<tr><td colspan="2">III</td></tr>
+<tr><td align='left'>Soap</td><td align='right'>80</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Filler</td><td align='right'>550</td><td align='center'>"</td></tr>
+<tr><td align='left'>Sal soda solution</td><td align='right'>170</td><td align='center'>"</td></tr>
+<tr><td colspan="2">IV</td></tr>
+<tr><td align='left'>Soap (settled tallow)</td><td align='right'>800</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Filler</td><td align='right'>400</td><td align='center'>"</td></tr>
+<tr><td align='left'>Sal soda solution</td><td align='right'>170</td><td align='center'>"</td></tr>
+<tr><td align='left'>Water</td><td align='right'>100</td><td align='center'>"</td></tr>
+</table></div>
+
+<p class="center">V</p>
+
+<p>First saponify 100 parts house grease and 100 parts ordinary grease and
+make a run soap. Then use in crutcher either:</p>
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Soap</td><td align='right'>400</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Filler</td><td align='right'>575</td><td align='center'>"</td></tr>
+<tr><td align='left'>Hot water</td><td align='right'>60</td><td align='center'>"</td></tr>
+<tr><td colspan="2">or</td></tr>
+<tr><td align='left'>Soap</td><td align='right'>200</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Hot water</td><td align='right'>200</td><td align='center'>"</td></tr>
+<tr><td align='left'>Filler</td><td align='right'>625</td><td align='center'>"</td></tr>
+</table></div>
+
+<p>It would be a simple matter to write numerous additional formulae, but
+the above are typical. The manufacturer must judge for himself just what
+filling material to use. The filler indicated in the above formulae is
+therefore left open. A few formulae for more expensive powders than
+those given recently appeared among others in the "Seifensieder
+Zeitung"<a name="FNanchor_9_9" id="FNanchor_9_9"></a><a href="#Footnote_9_9" class="fnanchor">[9]</a>:<span class='pagenum'><a name="Page_60" id="Page_60">[Pg 60]</a></span></p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td colspan="2">I</td></tr>
+<tr><td align='left'>Powdered soap</td><td align='right'>90</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Sodium perborate</td><td align='right'>10</td><td align='center'>"</td></tr>
+</table></div>
+
+<p>The perborate should be added when the powder is perfectly dry or it
+loses its bleaching properties.</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td colspan="2">II</td></tr>
+<tr><td align='right'>Soap powder, 20 per cent. fat.</td></tr>
+<tr><td align='left'>Cocoanut oil fatty acids</td><td align='right'>25</td><td align='right'> lbs.</td></tr>
+<tr><td align='left'>Olein</td><td align='right'>25</td><td align='center'>"</td></tr>
+<tr><td align='left'>Bone fat</td><td align='right'>70</td><td align='center'>"</td></tr>
+<tr><td align='left'>Soda lye, 30 degs. B.</td><td align='right'>90</td><td align='center'>"</td></tr>
+<tr><td align='left'>Water</td><td align='right'>150</td><td align='center'>"</td></tr>
+<tr><td align='left'>Ammonium carbonate</td><td align='left'>125</td><td align='center'>"</td></tr>
+<tr><td colspan="2">III</td></tr>
+<tr><td align='left'>Soap powder, 10 per cent. fat.</td></tr>
+<tr><td align='left'>Cocoanut oil fatty acids</td><td align='right'>20</td><td align='left'>lbs.</td></tr>
+<tr><td align='left'>Olein</td><td align='right'>10</td><td align='center'>"</td></tr>
+<tr><td align='left'>Bone fat</td><td align='right'>20</td><td align='center'>"</td></tr>
+<tr><td align='left'>Soda lye, 30 degs. B.</td><td align='right'>30</td><td align='center'>"</td></tr>
+<tr><td align='left'>Water</td><td align='right'>175</td><td align='center'>"</td></tr>
+<tr><td align='left'>Ammonium carbonate</td><td align='right'>175</td><td align='center'>"</td></tr>
+</table></div>
+
+<h3>LIGHT OR FLUFFY POWDERS.</h3>
+
+<p>Light or fluffy powders containing 35-45% moisture can be made in two
+ways. The first method requiring a minimum equipment is to mix the
+powder and sal soda in a mixer, allow it to stand in frames for a week
+to crystallize or spread it on the floor for a few hours to dry and then
+grinding it.</p>
+
+<p>The continuous method finishes the powder in a few minutes and with a
+minimum amount of labor. By this process the various ingredients, soap,
+soda ash solution, etc., are measured, run by gravity into the mixer,
+mixed and the molten mass run over the crystallizer or chilling rolls
+thru<span class='pagenum'><a name="Page_61" id="Page_61">[Pg 61]</a></span> which either cold water or brine is pumped. From the roll the
+powder is scraped off clean by a knife, passes to a screen which sends
+the tailings to a grinder, falls into a storage bin from whence it is
+weighed and packed by an automatic weighing machine into cartons made up
+in most cases by another machine. Due to the large percentage of
+moisture contained in these soap powders the carton is generally wrapped
+in wax paper to aid in the prevention of the escape of moisture.</p>
+
+
+<h4><span class="smcap">Scouring Powders.</span></h4>
+
+<p>Scouring powders are very similar to soap powders and differ only in the
+filler used. We have already considered these fillers under scouring
+soap, from which they do not differ materially. They are usually
+insoluble in water to aid in scouring. The mixer used for substances of
+this kind in incorporating the soap and alkali must be of strong
+construction.</p>
+
+
+<h3>SCOURING SOAP.</h3>
+
+<p>Scouring soaps resemble soap powders very closely in their composition,
+in that they are a combination of soap and filling material. Since more
+lather is required from a scouring soap than in soap powders, a cocoanut
+oil soap is generally used. The usual filling material used is silex.
+The greatest difficulty in the manufacture of scouring soap is the
+cracking of the finished cake. This is usually due to the incorporation
+of too great an amount of filler, or too high a percentage of moisture.</p>
+
+<p>In manufacturing these soaps the cocoanut oil is saponified in the
+crutcher with 38 degs. B. lye, or previously saponified as a run soap,
+as already described under "Marine Soaps." To twenty-five parts of soap
+are added a percentage of 38 degs. B. sal soda<span class='pagenum'><a name="Page_62" id="Page_62">[Pg 62]</a></span> or soda ash solution,
+together with a small quantity of salt brine. To this mixture in the
+crutcher seventy-five parts of silex are then added, and a sufficient
+amount of hot water to make the mass flow readily. Care must be
+exercised to not add too great a quantity of water or the mass will
+crack when it cools. The mass is then framed and cut before it sets, or
+poured into molds and allowed to set. While silex is the most
+extensively used filler for scouring soaps, it is feasible to
+incorporate other substances of like character, although it is to be
+remembered that the consumer is accustomed to a white cake, such as
+silex produces. Any other material used to replace silex should also be
+as fine as this product.</p>
+
+
+<h3>FLOATING SOAP.</h3>
+
+<p>Floating soap occupies a position midway between laundry and toilet
+soap. Since it is not highly perfumed and a large piece of soap may be
+purchased for small cost, as is the case with laundry soap, it is
+readily adaptable to general household use. Floating soap differs from
+ordinary soap in having air crutched into it which causes the soap to
+float in water. This is often advantageous, especially as a bath soap,
+and undoubtedly the largest selling brand of soap on the American market
+today is a floating soap.</p>
+
+<p>In the manufacture of floating soap a high proportion of cocoanut oil is
+necessary. A most suitable composition is one part cocoanut oil to one
+part of tallow. This is an expensive stock for the highest grade of soap
+and is usually cheapened by the use of cottonseed or various other
+liquid oils. Thus it is possible to obtain a floating soap from a kettle
+stocked with 30 per cent. cocoanut oil, 15 per cent. cottonseed oil and
+55 per cent. tallow. With this quality of soap, however, there is a
+possibility of sweating and<span class='pagenum'><a name="Page_63" id="Page_63">[Pg 63]</a></span> rancidity, and of the soap being too soft
+and being poor in color.</p>
+
+<p>The process of manufacture is to boil the soap in an ordinary soap
+kettle, after which air is worked into the hot soap by a specially
+constructed crutcher, after which the soap is framed, slabbed, cut into
+cakes and pressed.</p>
+
+<p>Concerning the boiling of the soap, the saponification must be carefully
+carried out, as the high proportion of cocoanut oil may cause a violent
+reaction in the kettle causing it to boil over.</p>
+
+<p>The method of procedure is the same as for a settled soap up to the
+finishing. When the mass is finally settled after the finish, the soap
+should be more on the "open" side, and the object should be to get as
+long a piece of goods as possible.</p>
+
+<p>Due to its high melting point, a much harder crust forms on the surface
+of a floating soap and in a greater proportion than on a settled soap
+during the settling. In a large kettle, in fact, it has been found
+impossible to break through this crust by the ordinary procedure to
+admit the skimmer pipe. Much of the success of the subsequent operations
+depends upon the completeness of the settling, and in order to overcome
+the difficulties occasioned by the formation of the crust everything
+possible should be done in the way of covering the kettle completely to
+enable this period of settling to continue as long as possible.</p>
+
+<p>When the soap is finished it is run into a specially constructed U-shape
+crutcher, a Strunz crutcher is best adapted to this purpose, although a
+rapidly revolving upright screw crutcher has been found to give
+satisfaction upon a smaller scale, and a sufficient quantity of air
+beaten into the soap to make it light enough to float. Care must be
+taken not to run the crutcher too rapidly or the soap will be entirely
+too fobby. During this operation the mass of<span class='pagenum'><a name="Page_64" id="Page_64">[Pg 64]</a></span> soap increases in bulk,
+and after it has been established how much air must be put into the soap
+to satisfy the requirements, this increase in bulk is a criterion to
+estimate when this process is completed.</p>
+
+<p>It is of course understood that the longer the crutching continues the
+greater quantity of air is incorporated and the increase of volume must
+be established for a particular composition by sampling, cooling the
+sample rapidly and seeing if it floats in water. If the beating is
+continued too long an interval of time, the finished soap is too spongy
+and useless.</p>
+
+<p>The temperature of the mass during crutching is most important. This
+must never exceed 158 degrees F. At 159 degrees F. the operation is not
+very successful, yet the thermometer may indicate 140 degrees F. without
+interfering with this operation. If, however, the temperature drops too
+low, trouble is liable to be met with, by the soap solidifying too
+quickly in the frames.</p>
+
+<p>When the crutching is completed, the soap is allowed to drop into frames
+through the valve at the bottom of the crutcher and rapidly crutched by
+the hand in the frames to prevent large air spaces and then allowed to
+cool. It is an improvement to jolt the frames as they are drawn away as
+this tends to make the larger air bubbles float to the surface and thus
+reduce the quantity of waste. When the soap has cooled, the frame is
+stripped and the soap slabbed as usual. At this point a layer of
+considerable depth of spongy soap will be found to have formed. This of
+course must be cut away and returned to the kettle. The last few slabs
+are also often rejected, inasmuch as the weight of the soap above them
+has forced out so much of the air that the soap no longer floats. As a
+fair average it may be estimated that not more than 50 to 60 per cent.
+of the soap in the kettle will come out as finished cakes.<span class='pagenum'><a name="Page_65" id="Page_65">[Pg 65]</a></span> the
+remaining 40 to 50 per cent. being constituted by the heavy crust in the
+kettle, the spongy tops, the bottom slabs and scrapings. This soap is of
+course reboiled and consequently not lost, but the actual cakes obtained
+are produced at a cost of practically double labor.</p>
+
+<p>It is advisable to add a small quantity of soap blue color to the mass
+while crutching to neutralize the yellowish tint a floating soap is
+liable to have.</p>
+
+<p>Some manufacturers add a percentage of carbonate of soda, about 3 per
+cent., to prevent the soap from shrinking. Floating soap may also be
+loaded with sodium silicate to the extent of about 5 per cent.</p>
+
+
+<h3>TOILET SOAP.</h3>
+
+<p>It is not a simple matter to differentiate between toilet soaps and
+various other soaps, because numerous soaps are adaptable to toilet
+purposes. While some soaps of this variety are manufactured by the cold
+made or semi-boiled process, and not milled, the consumer has become
+accustomed to a milled soap for general toilet use.</p>
+
+<p>The toilet base most extensively employed is a tallow and cocoanut base
+made as a full boiled settled soap. The manufacture of this base has
+already been outlined and really needs no further comment except that it
+is to be remembered that a suitable toilet soap should contain no great
+excess of free alkali which is injurious to the skin. Cochin cocoanut
+oil is preferable to the Ceylon cocoanut oil or palm kernel oil, to use
+in conjunction with the tallow, which should be a good grade and color
+if a white piece of goods is desired. The percentage of cocoanut oil may
+be anywhere from 10 to 25 per cent., depending upon the kind of lather
+required, it being remembered that cocoanut oil increases the lathering
+power of the soap.</p>
+
+<p>In addition to a tallow base, numerous other oils are<span class='pagenum'><a name="Page_66" id="Page_66">[Pg 66]</a></span> used in the
+manufacture of toilet soaps, especially palm oil, palm kernel oil, olive
+oil and olive oil foots, and to a much less extent arachis or peanut
+oil, sesame oil and poppy seed oil, oils of the class of cottonseed,
+corn and soya bean oils are not adapted to manufacturing a milled soap,
+as they form yellow spots in a finished cake of soap which has been kept
+a short time.</p>
+
+<p>Palm oil, especially the Lagos oil, is much used in making a palm base.
+As has already been stated, the oil is bleached before saponification. A
+palm base has a yellowish color, a sweetish odor, and a small quantity
+added to a tallow base naturally aids the perfume. It is especially good
+for a violet soap. The peculiarity of a palm oil base is that this oil
+makes a short soap. By the addition of some tallow or twenty to
+twenty-five per cent. of cocoanut oil, or both, this objection is
+overcome. It is a good plan in using a straight palm base to add a
+proportion of yellow color to hold the yellowish tint of this soap, as a
+soap made from this oil continues bleaching upon exposure to air and
+light.</p>
+
+<p>Olive oil and olive oil foots are used most extensively in the
+manufacture of castile soaps. The peculiarity of an olive oil soap is
+that it makes a very slimy lather, and like palm oil gives the soap a
+characteristic odor. An olive oil soap is usually considered to be a
+very neutral soap and may readily be superfatted. Much olive oil soap is
+used in bars or slabs as an unmilled soap and it is often made by the
+cold process. Peanut oil or sesame and poppy seed oil often replaces
+olive oil, as they form a similar soap to olive oil.</p>
+
+<p>In the manufacture of a toilet soap it is hardly practical to lay down a
+definite plan for the various bases to be made. From the combination of
+tallow, palm oil, cocoanut oil, palm kernel oil, olive oil and olive oil
+foots, a great<span class='pagenum'><a name="Page_67" id="Page_67">[Pg 67]</a></span> many bases of different proportions might be given. The
+simplest method is to make a tallow base, a palm base and an olive oil
+base. Then from these it is an easy matter to weigh out any proportion
+of these soap bases and obtain the proper mixture in the mill. If,
+however, as is often the case, a large quantity of soap base of certain
+proportions of these, four or even more of these fats and oils is
+required, it is not only more economical to stock the kettle with the
+correct proportion of these oils, but a more thorough mixture is thus
+obtained by saponifying these in the kettle. In view of the fact that it
+is really a question for the manufacturer to decide for himself what
+combination of oils he desires for a particular soap we will simply
+outline a few typical toilet soap bases in their simplest combination.
+It is understood that these soaps are suitable for milled soaps and are
+to be made as fully boiled settled soaps. Palm kernel oil may be
+substituted for cocoanut oil in all cases.</p>
+
+
+<h4>TALLOW BASE.</h4>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Tallow</td><td align='left'>75-90 parts</td></tr>
+<tr><td align='left'>Cocoanut oil</td><td align='left'>25-10 parts</td></tr>
+</table></div>
+
+
+
+<h4>PALM BASE.</h4>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Bleached Lagos palm oil</td><td align='left'>75-80 parts</td></tr>
+<tr><td align='left'>Cocoanut oil</td><td align='left'>25-20 parts</td></tr>
+</table></div>
+
+<p class="center">or</p>
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Tallow</td><td align='left'>30 parts</td></tr>
+<tr><td align='left'>Palm oil</td><td align='left'>60 parts</td></tr>
+<tr><td align='left'>Cocoanut oil</td><td align='left'>10 parts</td></tr>
+</table></div>
+
+
+
+<h4>OLIVE OIL BASE (WHITE).</h4>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Olive oil</td><td align='left'>75-90 parts</td></tr>
+<tr><td align='left'>Cocoanut oil</td><td align='left'>25-10 parts</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_68" id="Page_68">[Pg 68]</a></span></p>
+
+<p class="center">or</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Olive oil</td><td align='left'>40 parts</td></tr>
+<tr><td align='left'>Tallow</td><td align='left'>40 parts</td></tr>
+<tr><td align='left'>Cocoanut</td><td align='left'>20 parts</td></tr>
+</table></div>
+
+
+<p>Where a green olive oil base is desired, olive oil foots are substituted
+for the olive oil. Peanut oil may replace the olive oil or part of it,
+the same being true of sesame oil and poppy seed oil.</p>
+
+
+<h4>PALM AND OLIVE BASE.</h4>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Palm oil</td><td align='left'>50 parts</td></tr>
+<tr><td align='left'>Olive oil</td><td align='left'>30 parts</td></tr>
+<tr><td align='left'>Cocoanut oil</td><td align='left'>20 parts</td></tr>
+</table></div>
+
+<p class="center">or</p>
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Palm oil</td><td align='left'>20 parts</td></tr>
+<tr><td align='left'>Olive oil</td><td align='left'>10 parts</td></tr>
+<tr><td align='left'>Tallow</td><td align='left'>50 parts</td></tr>
+<tr><td align='left'>Cocoanut oil</td><td align='left'>20 parts</td></tr>
+</table></div>
+
+
+
+<h3>CHEAPER TOILET SOAPS.</h3>
+
+<p>It is often necessary to manufacture a cheaper grade of soap for toilet
+purposes to meet the demand of a certain class of trade as well as for
+export. To accomplish this it is of course necessary to produce a very
+inferior product and run down the percentage of fatty acids contained in
+the soaps by the addition of fillers or to use cheaper oils in
+manufacturing. The most simple method of filling a soap is to load it at
+the mill with some substance much less expensive than the soap itself.
+Many of the cheaper toilet soaps, however, are not milled and it is,
+therefore, necessary to follow out some other procedure.</p>
+
+<p>Milled soaps, as has just been stated, are loaded at the mill. The
+consumers of cheaper toilet soaps in this country are accustomed to a
+milled soap and this grade of soap for home consumption is very often
+filled with<span class='pagenum'><a name="Page_69" id="Page_69">[Pg 69]</a></span> numerous substances, but most generally by adding starch
+and talc. The addition of such materials of course later exhibit
+themselves by imparting to the cake of soap a dead appearance. Talc is
+more readily detected in the soap than starch by washing with it, as
+talc is insoluble and imparts a roughness to the soap, like sand or
+pumice, as the soap wears down. It may readily be added to 20 per cent.
+by weight. Starch is to be preferred to talc, in loading a soap, as it
+is not so readily noticeable in washing. It leaves the cake itself
+absolutely smooth although the lather formed is more shiny. This
+substance may be employed to as high a percentage as one-third the
+weight of the soap. It is, of course, possible to cheapen the best soap
+base by this method and the price may be further lowered by using the
+less expensive oils and fats to make the soap base.</p>
+
+
+<h3>RUN AND GLUED UP SOAPS.</h3>
+
+<p>A very cheap grade of soap may be made by making a run soap and adding
+the filler e. g. sodium silicate in the kettle during saponification.
+The percentage of fatty acids may be brought down to 10 per cent.,
+although of course a soap of this type shrinks a whole lot upon
+exposure.</p>
+
+<p>In making a "glued up" soap the procedure is the same for making the
+soap itself as with a settled soap, except that the soap is finished
+"curd" and later filled in the crutcher. The percentage of fatty acids
+in a soap of this type is seldom below 50 per cent.</p>
+
+<p>The method of "gluing up" a soap is best illustrated by a typical soap
+of this character in which the kettle is charged with the following
+stock.</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Bleached palm oil</td><td align='left'>5</td><td align='center'> parts</td></tr>
+<tr><td align='left'>Distilled grease</td><td align='left'>2</td><td align='center'>"</td></tr>
+<tr><td align='left'>Cotton oil foots stock, 63% fatty acid</td><td align='left'>1</td><td align='center'>"</td></tr>
+<tr><td align='left'>Rosin</td><td align='left'>4</td><td align='center'>"</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_70" id="Page_70">[Pg 70]</a></span></p>
+<p>The palm oil is first run into the kettle, saponified and washed to
+extract any glycerine, then the rest of the fats and finally the rosin.
+The soap is then finished and settled as with a boiled settled soap. To
+assure success it is absolutely necessary that the soap settle as long a
+period as possible, or until the temperature is about 150 degs. F. The
+ideal temperature for carrying out the "gluing up" process is 140 degs.
+F., as at a lower temperature than this the soap is liable to cool too
+quickly and not be thoroughly glued up. A higher temperature than 150
+degs. F. causes delay in that the soap does not properly take the filler
+at a higher temperature and the soap must be kept in the crutcher until
+the temperature drops to the right point.</p>
+
+<p>The soap is run into the crutcher and the percentage of fatty acids run
+down to 50-55 per cent. with one of the following mixtures:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Sodium silicate, 59-1/2&deg; B.</td><td align='left'>1</td><td align='center'> part</td></tr>
+<tr><td align='left'>Potassium carbonate, 51&deg; B.</td><td align='left'>1</td><td align='center'>"</td></tr>
+</table></div>
+
+<p class="center">or</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Sodium silicate, 59-1/2&deg; B.</td><td align='left'>1</td><td align='center'> part</td></tr>
+<tr><td align='left'>Potassium carbonate, 51&deg; B.</td><td align='left'>1</td><td align='center'>"</td></tr>
+<tr><td align='left'>Sodium sulfate, 28&deg; B.</td><td align='left'>1</td><td align='center'>"</td></tr>
+</table></div>
+
+
+<p>From 230 to 300 pounds of either of these mixtures are required for a
+crutcher holding 2,600 pounds of soap.</p>
+
+<p>The crutching is continued until the mass is well "spiked," that is to
+say, a freshly broken surface of the soap, as the crutcher blade is
+jerked away, stands up like shattered sheets in triangular form (&#916;
+&#916; &#916;), which retain their shape perfectly.
+When this condition is realized the soap is run into frames which are
+carefully crutched by hand to remove any air spaces. The surface of the
+soap is then smoothed down and heaped up in the center. After standing a
+day to contract, the surface is again leveled and a<span class='pagenum'><a name="Page_71" id="Page_71">[Pg 71]</a></span> snugly-fitting
+board placed on the top of the soap upon which a weight is placed or
+upon which the workman treads and stamps until the surface is flat, thus
+assuring the further removal of air spaces. The soap remains in the
+frame from six to eight days and is then slabbed, barred and pressed by
+the usual method employed for soaps thus handled without milling.</p>
+
+<p>In a soap of this nature no hard and fast rule can be laid down as to
+the quantity of solution to be used for "gluing up" or the strength of
+the solution. In a soap of the type described the most satisfactory
+appearing cake will be obtained from a soap containing 58 per cent.
+fatty acids. That is to say, about 8 per cent. to 10 per cent. filling
+solution is added per hundred pounds of soap. The filling solutions
+given are very satisfactory. Carbonate of soda should be avoided in
+connection with sodium silicate as the property of efflorescing on the
+surface of the finished cake after a short time will prove detrimental.
+To assure successful gluing up it is advisable to experiment upon a
+small scale to determine the exact extent to which the filling solution
+should be diluted. Various proportions of water are added to a certain
+quantity of the filled soap. After the soap has been filled in a small
+receptacle a sample is taken and rubbed between the fingers. If the
+freshly exposed surface is smooth and glossy, the filling solution is
+weak enough, if rough it is too strong. It is of course understood that
+the temperature must be correct, 140 degs. to 150 degs. F., or the soap
+will be rough. By this means the operator can readily judge the correct
+strength of his filling solution. When properly carried out a perfectly
+satisfactory soap is obtained.</p>
+
+
+<h3>CURD SOAP.</h3>
+
+<p>The object of a soap which is finished "curd" or grained, is to obtain a
+harder piece of goods from low titer fat or<span class='pagenum'><a name="Page_72" id="Page_72">[Pg 72]</a></span> to increase the percentage
+of fatty acids in the finished soap. This is still another method of
+producing a cheap grade of soap as by its adoption the cheaper oils and
+fats may be used to obtain a firm piece of soap.</p>
+
+<p>A typical charge for curd soap is:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Red oil</td><td align='left'>63</td><td align='center'>parts</td></tr>
+<tr><td align='left'>Tallow</td><td align='left'>10</td><td align='center'>"</td></tr>
+<tr><td align='left'>Rosin</td><td align='left'>27</td><td align='center'>"</td></tr>
+</table></div>
+
+
+<p>Cotton seed foots may be employed in place of red oil and a tallow of
+too high titer is not suitable for this kind of soap.</p>
+
+<p>The red oil and tallow are first saponified with 15 degs. B. lye, boiler
+pressure 80-90 pounds, 18 degs. B. lye for lower steam pressure, and two
+washings given to extract the glycerine. The rosin is added at the
+strengthening change and at the finish the soap is "pitched," that is to
+say, the soap is settled over night only. The next day the lyes are
+drawn off and a portion of the nigre pumped to another kettle which
+prevents later streaking of the soap. The soap is then boiled with 18
+degs. B. lye as with another strengthening change under closed steam.
+Salt brine or "pickle," 15 degs. B. is then added and the mass boiled
+with closed steam until the brine reaches a density of 18 degs. B. and
+the kettle pumped the next day. A soap of this type requires either hand
+or power crutching to assure homogeneity and prevention of streaks. To
+obviate any air spaces it is advisable to place over the top of the
+frame a tightly-fitted board which is heavily weighted down. This soap
+is also pressed without any milling.</p>
+
+
+<h3>COLD MADE TOILET SOAPS.</h3>
+
+<p>Comparatively little toilet soap is made by the cold or semi-boiled
+processes. While these are the simplest<span class='pagenum'><a name="Page_73" id="Page_73">[Pg 73]</a></span> methods of manufacturing soaps
+the drawbacks of using them are numerous and only in a few cases are
+they very extensively employed. To make a toilet soap by the cold
+process a combination of good grade tallow and cocoanut oil is required.
+It requires 50 per cent. by weight of 36 degs. B. lye to saponify a
+given weight of tallow and 50 per cent. of 38 degs. B. lye for cocoanut
+oil. The lyes are used full strength or may be reduced slightly with
+water and the method of procedure is the same as already given in the
+general directions for cold made soaps.</p>
+
+<p>Cold made soaps are readily filled with sodium silicate which is added
+at the same time the stock is put into the crutcher. In adding the
+silicate it is necessary to add additional lye to that required for
+saponifying the fats, about 20 per cent. of 36 degs. B. lye is the
+proper amount. There is of course a certain amount of shrinking due to
+the addition of this filler and the finished cake is exceedingly hard,
+yet the author has seen a good looking cake of cheap soap made from as
+high a proportion as 420 parts of tallow to 600 parts of silicate.</p>
+
+<p>Cold made soaps are usually pressed without milling, although it is
+readily feasible to mill a cold made soap provided it is not a filled
+soap such as has just been described.</p>
+
+
+<h3>PERFUMING AND COLORING TOILET SOAPS.</h3>
+
+<p>Equally important as the soap itself or even to a greater extent is the
+perfume of a toilet soap. A prominent manufacturer recently made the
+statement, which is often the truth, that it makes no difference to the
+public what kind of soap you give them, as long as you put plenty of
+odor into it. The perfuming of soaps is an art in itself and a subject
+to be treated by one versed in this particular branch. We can only take
+into account the importance of<span class='pagenum'><a name="Page_74" id="Page_74">[Pg 74]</a></span> the perfume as related to toilet soap
+not only, but the necessity of adding a certain proportion of the
+cheaper products of odoriferous nature to laundry soap to cover and
+disguise the odor of even this type of soap.</p>
+
+<p>The price of a cake of toilet soap to a great extent depends upon the
+perfume, and the manufacturer should aim to give the best possible
+perfume for a certain price. He should not allow his personal likes or
+dislikes to enter into the judgment of whether an odor is good or not,
+but submit it to a number of persons to obtain the concensus of opinion.
+In giving or selling a piece of soap to the consumer, it is second
+nature for him to smell it, and in the great majority of cases his
+opinion is formed not from any quality the soap itself may have during
+use, but from the odor. This only emphasizes the fact that the perfume
+must be pleasing, not to one person, but to the majority, and many
+brands owe their popularity to nothing more than the enticing perfume.</p>
+
+<p>Perfuming of soap is closely allied to the soap making industry, but as
+stated a branch in itself. It is, therefore, not our purpose to give
+numerous formulae of how to perfume a soap, but rather to advise to go
+for information to some one who thoroughly understands the
+characteristics of the numerous essential oils and synthetics and give
+positive information for the particular odor desired. Under no
+circumstances is it advisable to purchase a perfume already compounded,
+but since all perfumes are a blend of several or many essential oils and
+synthetics, it is a more positive assurance of obtaining what is
+desired, by purchasing the straight oils and blending or mixing them as
+one desires.</p>
+
+<p>The perfume is added to a milled soap just before the milling process in
+the proper proportion per hundred pounds of soap. In cold made or
+unmilled soaps it is<span class='pagenum'><a name="Page_75" id="Page_75">[Pg 75]</a></span> added in the crutcher while the soap is still hot.
+By this method, of course, a proportion of the perfume is lost due to
+its being more or less volatile.</p>
+
+
+<h3>COLORING SOAP.</h3>
+
+<p>While much toilet soap is white or natural in color, many soaps are also
+artificially colored. The soap colors used for this purpose are mostly
+aniline dyestuffs. The price of these dyestuffs is no criterion as to
+their quality, as the price is usually regulated by the addition of some
+inert, water soluble substance like common salt or sugar.</p>
+
+<p>The main properties that a dyestuff suitable for producing a colored
+soap should have are fastness to light and to alkali. They should
+further be of such a type that the color does not come off and stain a
+wash cloth or the hands when the soap is used and should be soluble in
+water. Under no circumstances is it advisable to add these in such a
+quantity that the lather produced in the soap is colored. It is
+customary to first dissolve the dye in hot water as a standardized
+solution. This can then be measured out in a graduate and added to the
+soap the same time as the perfume is put in. About one part of color to
+fifty parts of water is the proper proportion to obtain a perfect
+solution, though this is by no means fixed. In making up a solution thus
+it is an improvement to add to the same about one-half of one per cent.
+of an alkali either as the hydroxide or carbonate. Then, if there is any
+possibility of change of color due to alkalinity of the soap, it will
+exhibit itself before the color is added.</p>
+
+<p>A particularly difficult shade to obtain is a purple, as there is up to
+the present time no purplish aniline color known which is fast to light.
+Very good results in soap may be obtained by mixing a fast blue, as
+ultramarine or cobalt blue, with a red as rhodamine or eosine.<span class='pagenum'><a name="Page_76" id="Page_76">[Pg 76]</a></span></p>
+
+<p>Inasmuch as the colors for soap have been carefully tested by most of
+the dyestuff manufacturers, and their information, usually reliable, is
+open to any one desiring to know about a color for soap, it is better to
+depend upon their experience with colors after having satisfied one's
+self that a color is what it is represented for a particular shade, than
+to experiment with the numerous colors one's self.</p>
+
+
+<h3>MEDICINAL SOAPS.</h3>
+
+<p>Soap is often used for the conveyance of various medicants, antiseptics
+or other material presumably beneficial for treatment of skin diseases.
+While soap is an ideal medium for the carrying of such materials, it is
+an unfortunate condition that when incorporated with the soap, all but a
+very few of the numerous substances thus employed lose their medicinal
+properties and effectiveness for curing skin disorders, as well as any
+antiseptic value the substance may have. Soap is of such a nature
+chemically that many of the substances used for skin troubles are either
+entirely decomposed or altered to such an extent so as to impair their
+therapeutic value. Thus many of the claims made for various medicated
+soaps fall flat, and really have no more antiseptic or therapeutic merit
+than ordinary soap which in itself has certain germicidal and cleaning
+value.</p>
+
+<p>In medicating a soap the material used for this purpose is usually added
+at the mill. A tallow and cocoanut oil base is best adapted for a soap
+of this type. The public have been educated more or less to the use of
+colored soap to accentuate its medicinal value, and green is undoubtedly
+the most popular shade. This inference, however, is by no means true for
+all soaps of this<span class='pagenum'><a name="Page_77" id="Page_77">[Pg 77]</a></span> character. Possibly the best method of arranging
+these soaps is briefly to outline some medicinal soaps.</p>
+
+
+<h3>SULPHUR SOAPS.</h3>
+
+<p>The best known sulphur soaps contain anywhere from one to 20 per cent.
+of flowers of sulphur. Other soaps contain either organic or inorganic
+sulphur compounds.</p>
+
+
+<h3>TAR SOAP.</h3>
+
+<p>The tar used in the manufacturing of tar soap is obtained by the
+destructive distillation of wood, the pine tar being the most
+extensively employed. While the different wood tars contain numerous
+aromatic compounds, such as phenols, phenyl oxides, terpenes and organic
+acids, these are present in such a slight proportion so as to render
+their effectiveness practically useless. It has, therefore, been tried
+to use these various compounds contained in the tar themselves to make
+tar soap really effective, yet tar is so cheap a substance that it is
+usually the substance used for medicating a tar soap. About 10 per cent.
+of tar is usually added to the soap with 2 ounces of lamp black per
+hundred pounds of soap.</p>
+
+
+<h3>SOAPS CONTAINING PHENOLS.</h3>
+
+<p>Phenol (Carbolic Acid) is most extensively used in soaps of this kind,
+which are called carbolic soaps. Carbolic soaps are generally colored
+green and contain from 1 to 5 per cent. phenol crystals.</p>
+
+<p>The cresols are also extensively used for making soaps named carbolic.
+These substances impart more odor to the soap and really have more
+disinfecting powers than phenol when incorporated with soap.</p>
+
+<p>Other soaps, containing the phenol group, which are well known are
+resorcinol soap, salol soap, thymol soap,<span class='pagenum'><a name="Page_78" id="Page_78">[Pg 78]</a></span> naphthol soap, etc. From one
+to five per cent of the compound after which the soap is named is
+usually incorporated with the soap.</p>
+
+
+<h3>PEROXIDE SOAP.</h3>
+
+<p>Hydrogen peroxide in itself is an excellent disinfectant. It loses all
+its medicinal value, however, when added to the soap. To overcome this
+objection various metallic peroxides are added to the soap, as sodium
+peroxide, zinc peroxide and barium peroxide. These generate hydrogen
+peroxide by the addition of water. Sodium perborate is also used in
+peroxide soaps, as this substance is decomposed by water into hydrogen
+peroxide and sodium metaborate.</p>
+
+
+<h3>MERCURY SOAPS.</h3>
+
+<p>Mercuric chloride (corrosive sublimate) is most extensively used for the
+production of mercury soaps. Because of its extremely poisonous
+properties care should be taken in using it. Since it really eventually
+loses any antiseptic value in the soap through forming an insoluble
+mercury soap it might better be omitted entirely.</p>
+
+
+<h3>LESS IMPORTANT MEDICINAL SOAPS.</h3>
+
+<p>While the above mentioned soaps are probably the best known medicated
+soaps, there are numerous other soaps which may be classed under these
+kinds of soaps. Thus we have cold cream soap, which can be made by
+adding Russian Mineral Oil, 1 to 5 per cent., to the soap; witch hazel
+soap, made by the addition of extract of witch hazel; iodine soap, made
+by adding iodine or iodoform; formaldehyde soap, made by adding
+formaldehyde; tannin soaps, made by adding tannin. In fact, there have
+been incorporated in soap so great a<span class='pagenum'><a name="Page_79" id="Page_79">[Pg 79]</a></span> number of substances that the list
+might be greatly enlarged.</p>
+
+<p>Medicated soaps are not only used in solid form, but in powder, paste
+and liquid soap as well. The only difference in a soap like those just
+referred to is that the medicant is incorporated with these forms of
+soaps as convenience directs.</p>
+
+
+<h3>CASTILE SOAP.</h3>
+
+<p>A pure castile soap should be made from olive oil. This, however, is not
+always the case, as a number of oils as well as tallow are used to
+adulterate this oil to cheapen it, and there are even some soaps called
+castile which contain no olive oil at all. Most of the pure castile soap
+used in this country is imported, as it is a difficult matter for the
+American manufacturer to compete with the pure imported castile soap,
+since both labor and oil itself are so much cheaper in the vicinities of
+Europe where this oil is produced, that this advantage is more than
+compensated by the carrying and custom charges by importing the castile
+soap.</p>
+
+<p>Castile soap may be made either by the full boiled or cold process.
+There are numerous grades of olive oil, and those used for soap making
+are denatured to lower the duty charges. Olive oil makes a hard white
+soap, usually sold in bars, and olive oil foots a green soap, due to the
+coloring matter contained in this oil.</p>
+
+<p>To make a boiled castile soap, a composition of 10 per cent. Cochin
+cocoanut oil and 90 per cent. olive oil may be used. To cheapen this,
+peanut oil (Arachis oil) may entirely replace the olive oil, or about 20
+per cent. of corn or soya bean oil may be added. The oils are saponified
+as usual in making a settled soap and to prevent rancidity the soap is
+boiled near the finish for<span class='pagenum'><a name="Page_80" id="Page_80">[Pg 80]</a></span> some time in the closed state with
+sufficient excess of alkali to give it a sharp taste, then grained with
+lye, the lye drawn off, closed with water and then grained with salt.
+This process is repeated until the desired strength is reached. The last
+graining should not be too great, and on the last change the soap should
+not be thinned out, as it will contain too great a quantity of water
+when slabbed.</p>
+
+<p>In making a cold castile soap the usual method is pursued as already
+directed under cold made soap. When the soap is taken from the crutcher
+it is advisable, however, to keep the soap in the frame well covered to
+assure complete saponification. Some manufacturers use very small frames
+which are placed into compartments, well insulated to retain heat.
+Several formulae for cold made castile soaps, follow. It may be noted
+that some of these contain practically no olive oil.</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td colspan="2">I</td></tr>
+<tr><td align='left'>Olive oil</td><td align='right'>2030</td></tr>
+<tr><td align='left'>Palm kernel</td><td align='right'>674</td></tr>
+<tr><td align='left'>Soda lye, 35 per cent. B.</td><td align='right'>1506</td></tr>
+<tr><td colspan="2">II</td></tr>
+<tr><td align='left'>Olive oil</td><td align='right'>2030</td></tr>
+<tr><td align='left'>Cochin cocoanut oil</td><td align='right'>674</td></tr>
+<tr><td align='left'>Soda lye, 36 per cent. B.</td><td align='right'>1523</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='right'>82</td></tr>
+<tr><td colspan="2">III</td></tr>
+<tr><td align='left'>Palm kernel oil</td><td align='right'>1578</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>940</td></tr>
+<tr><td align='left'>Olive oil</td><td align='right'>7</td></tr>
+<tr><td align='left'>Sodium silicate, 20 per cent.</td><td align='right'>190</td></tr>
+<tr><td align='left'>Soda lye, 36 per cent. B.</td><td align='right'>1507</td></tr>
+<tr><td align='left'><span class='pagenum'><a name="Page_81" id="Page_81">[Pg 81]</a></span></td></tr>
+<tr><td colspan="2">IV</td></tr>
+<tr><td align='left'>Olive oil (yellow)</td><td align='right'>1000</td></tr>
+<tr><td align='left'>Soda lye, 37 per cent. B.</td><td align='right'>500</td></tr>
+<tr><td colspan="2">V</td></tr>
+<tr><td align='left'>Olive oil</td><td align='right'>90</td></tr>
+<tr><td colspan="2">or</td></tr>
+<tr><td align='left'>Palm kernel &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}</td><td align='right'>10</td></tr>
+<tr><td align='left'>Cochin or cocoanut oil }</td><td align='right'>10</td></tr>
+<tr><td align='left'>Lye, 37 per cent. B.</td><td align='right'>51</td></tr>
+</table></div>
+
+<p>If any of the soaps containing a high proportion of cocoanut oil are
+boiled the soap will float. It is therefore necessary to keep the
+temperature as low as possible.</p>
+
+
+<h3>ESCHWEGER SOAP (BLUE MOTTLED).</h3>
+
+<p>Eschweger soap is a colored mottled or marbled soap made to a very
+slight extent in this country. Inasmuch as it has been introduced to the
+export trade, it is made for this purpose by some manufacturers. A high
+percentage of cocoanut oil is usually used together with tallow and
+grease. About one-third of each is a typical formula. In a soap of this
+character the fact that cocoanut oil soap takes up a large quantity of
+water and salts of various kinds and is difficult to salt out is made
+use of. The tallow and grease are first saponified as usual, then the
+cocoanut oil is pumped and saponified. When the saponification is nearly
+completed either silicate or carbonate of soda or common salt are added
+to make the soap "short" so as to form the mottle. The finishing of a
+soap of this type can only be gained by practice and it is rather
+difficult to explain the exact appearance of the kettle at this stage.
+The surface of the soap should be bright and lustrous with the steam<span class='pagenum'><a name="Page_82" id="Page_82">[Pg 82]</a></span>
+escaping in numerous places in rose-like formation. A sample on the
+trowel should have a slight sharpness to the tongue and be plastic. When
+the soap slides from the trowel it should break short. When the soap has
+reached this stage the desired coloring matter, usually ultramarine, is
+added to the soap either in the kettle or crutcher and the soap framed.
+The yield is 200-215 pounds per hundred pounds of stock.</p>
+
+<p>Several modifications of this general method for Eschweger soap are used
+by adopting the half boiled or cold process.</p>
+
+
+<h4><span class="smcap">Transparent Soap.</span></h4>
+
+<p>Transparent soap is really not a most desirable soap for toilet
+purposes, as it contains an excess of free alkali. It has, nevertheless,
+met with public approval because of the fact it is novel in being
+transparent. Except for this fact very little merit can be claimed for a
+soap of this kind.</p>
+
+<p>The transparency of soap is generally due to the presence of alcohol,
+sugar or glycerine in the soap when it is made. It is very essential in
+a soap of this character, where lightness and clearness of color are
+desired, that the material for making the soap be carefully selected as
+to color and purity. The perfumes also play an important part in the
+color of the soap and many of the tinctures, balsams and infusions used
+in perfuming soap may eventually cause trouble by spotting. If the soap
+is artificially colored, which is almost always the case, the dyestuffs
+used for this purpose should have careful attention and only those
+should be used which are known to resist the action of alkalis. Where
+rosin is used this product must be of the better grade. Distilled water
+is always preferable for use in transparent soap. The government permits
+the use of a specially denatured alcohol. This alcohol is not taxed and
+consists of grain (ethyl) alcohol denatured with 5 per cent. wood<span class='pagenum'><a name="Page_83" id="Page_83">[Pg 83]</a></span>
+(methyl) alcohol. Some soapmakers prefer to use a more expensive refined
+methyl alcohol, but outside of adding to the cost of the soap, there is
+no particular advantage. The glycerine should be chemically pure. As to
+the oils and fats these should be low in acid and of good color. Under
+no circumstances should the crutcher or kettle in which the soap is made
+be rusty or unclean in any way. For a light soap enameled utensils are
+to be preferred.</p>
+
+<p>To obtain transparency in soap the following general methods may be
+given.</p>
+
+<p>1. Where the transparency is due to sugar.</p>
+
+<p>2. Where alcohol and glycerine produce transparency.</p>
+
+<p>3. Where (1) or (2) is supplemented by the use of castor oil.</p>
+
+<p>4. Where transparency depends upon the percentage of fatty acid in a
+soap and the number of times the soap is milled.</p>
+
+<p>Under the first method at least 25 per cent. of the charge should be
+cocoanut oil, the other constituent being tallow or any fat or oil
+capable of giving a sufficiently hard soap. The soap is boiled and
+finished as usual, then run to the crutcher to be mixed with a strong
+cane sugar solution, containing 10-20 per cent. sugar of the weight of
+the soap. The sugar is dissolved in its own weight of water and the
+solution heated to 175 degs. F. before being very slowly added to the
+soap. As the water evaporates, soaps of this type show spots due to the
+sugar thus being thrown out of solution.</p>
+
+<p>Transparent soap made under the second method may be saponified as usual
+and consist of any good toilet base. The soap is run to the crutcher and
+mixed with 95 per cent. alcohol in the proportion of one part alcohol to
+two parts of fatty acid contained in the soap together with glycerine in
+the same proportion.<span class='pagenum'><a name="Page_84" id="Page_84">[Pg 84]</a></span></p>
+
+<p>By the third method castor oil alone may be used to make the soap or
+added to any of the above bases up to 33-1/3 per cent. of the charge. If
+castor oil only is used, but 2 per cent. or 3 per cent. of sugar is
+required.</p>
+
+<p>In the last method a combination of 80 per cent. tallow, very low in
+free acid, 20 per cent. cocoanut oil and 5 per cent. W. W. rosin is a
+suitable charge. The saponification and finishing is carried out as with
+a full boiled soap. The soap is then placed into a jacketed vessel,
+provided with dry-steam coils, by which the excess water is evaporated
+from the soap until it contains 73 per cent. fatty acids. When the thick
+mass reaches this stage it is framed and when cool is suitable for
+obtaining a semi transparency which now depends upon the number of times
+the soap is milled, it being, of course, inferred that no solid matter
+of any sort be added to the soap.</p>
+
+
+<h4><span class="smcap">Cold Made Transparent Soap.</span></h4>
+
+<p>While transparent soaps may be made by the above general methods they
+are usually made by the semi-boiled or cold process. By this process a
+more satisfactory soap is obtained and it is more simple to carry out. A
+detailed description of this method is best and most easily given by
+using a typical formula.</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Charge:</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>193-1/2</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Cochin Cocoanut Oil</td><td align='right'>169-1/2</td><td align='center'>"</td></tr>
+<tr><td align='left'>Castor Oil</td><td align='right'>89-1/2</td><td align='center'>"</td></tr>
+<tr><td align='left'>Soda Ash</td><td align='right'>7-3/4</td><td align='center'>"</td></tr>
+<tr><td align='left'>Soda Lye, 36 degs. B.</td><td align='right'>256</td><td align='center'>"</td></tr>
+<tr><td align='left'>Sugar (Cane)</td><td align='right'>198</td><td align='center'>"</td></tr>
+<tr><td align='left'>Alcohol</td><td align='right'>126</td><td align='center'>"</td></tr>
+<tr><td align='left'>Water (Distilled)</td><td align='right'>80</td><td align='center'>"</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_85" id="Page_85">[Pg 85]</a></span></p>
+
+<p>To proceed, first place into a crutcher or jacketed kettle the oils and
+fat and heat to 140 degs. F. Then add the soda ash dissolved in about 30
+pounds of the water, after which the lye is added and the mass stirred
+until a finger or stick run over the surface leaves an imprint. Where
+the soap has reached this stage, it is well covered and allowed to stand
+about two hours or until it bulges in the center, after which the rest
+of the water which should contain no lime or other mineral substance and
+which is preferably distilled water, is added. The sugar is then slowly
+shoveled in while the mass is stirring and finally the alcohol is poured
+in. The heat is then increased to 160 degs. F. by dry steam and the soap
+crutched until dissolved. Under no circumstances should any soap be
+allowed to remain above the surface of the mass on the sides of the
+mixer. This crutching operation consumes about one hour, and when
+finished the soap should stand in the vessel about half an hour when a
+small sample is taken out to cool. This sample should be clear and show
+an excess of alkali. If it is not clear more alcohol is added, if not of
+sufficient strength more lye put in until the desired condition is
+reached. The perfume and color are now added.</p>
+
+<p>The soap is then framed and allowed to set after which it is cut,
+allowed to dry slightly and then pressed. To obtain a polished cake
+transparent soaps are often planed before pressing and after pressing
+polished with a soft cloth, dampened with alcohol. Instead of framing
+this soap, it is sometimes "tubed," that is to say, the soap from the
+crutcher is run into specially constructed tubes of a shape near that of
+the desired cake and allowed to cool, after which it is cut and pressed.
+All scraps are returned to the crutcher, but in so doing the soap is
+slightly darkened in color. It is advisable to expose a finished cake of
+transparent<span class='pagenum'><a name="Page_86" id="Page_86">[Pg 86]</a></span> soap to the air for some time as by so doing it becomes
+clearer.</p>
+
+<p>Other formulae for cold made transparent soaps made as just outlined
+follow:</p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td colspan="2">I.</td></tr>
+<tr><td align='left'>Bleached Tallow</td><td align='right'>134</td><td align='center'>lbs.</td></tr>
+<tr><td align='left'>Cochin Cocoanut Oil</td><td align='right'>88</td><td align='center'>"</td></tr>
+<tr><td align='left'>Castor Oil</td><td align='right'>20</td><td align='center'>"</td></tr>
+<tr><td align='left'>W. W. Rosin</td><td align='right'>7</td><td align='center'>"</td></tr>
+<tr><td align='left'>Cane Sugar</td><td align='right'>64</td><td align='center'>"</td></tr>
+<tr><td align='left'>Water</td><td align='right'>32</td><td align='center'>"</td></tr>
+<tr><td align='left'>Glycerine</td><td align='right'>34</td><td align='center'>"</td></tr>
+<tr><td align='left'>Soda Lye, 38 degs. B.</td><td align='right'>135</td><td align='center'>"</td></tr>
+<tr><td align='left'>Alcohol</td><td align='right'>16</td><td align='center'>gal.</td></tr>
+<tr><td colspan="2">II.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>211</td><td align='center'>lbs.</td></tr>
+<tr><td align='left'>Cochin Cocoanut Oil</td><td align='right'>185</td><td align='center'>"</td></tr>
+<tr><td align='left'>Castor Oil</td><td align='right'>97-1/2</td><td align='center'>"</td></tr>
+<tr><td align='left'>Soda Ash</td><td align='right'>8-1/2</td><td align='center'>"</td></tr>
+<tr><td align='left'>Water</td><td align='right'>106</td><td align='center'>"</td></tr>
+<tr><td align='left'>Soda Lye, 38 degs. B.</td><td align='right'>279</td><td align='center'>"</td></tr>
+<tr><td align='left'>Sugar</td><td align='right'>216</td><td align='center'>"</td></tr>
+<tr><td align='left'>Alcohol</td><td align='right'>137</td><td align='center'>"</td></tr>
+<tr><td colspan="2">III.</td></tr>
+<tr><td align='left'>Castor Oil</td><td align='right'>60</td><td align='center'>lbs.</td></tr>
+<tr><td align='left'>Cochin Cocoanut Oil</td><td align='right'>195</td><td align='center'>"</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>120</td><td align='center'>"</td></tr>
+<tr><td align='left'>Alcohol</td><td align='right'>115</td><td align='center'>"</td></tr>
+<tr><td align='left'>Sugar</td><td align='right'>90</td><td align='center'>"</td></tr>
+<tr><td align='left'>Water</td><td align='right'>53</td><td align='center'>"</td></tr>
+<tr><td align='left'>Glycerine</td><td align='right'>53</td><td align='center'>"</td></tr>
+<tr><td align='left'>Soda Lye, 38 degs. B.</td><td align='right'>205-1/2</td><td align='center'>"</td></tr>
+<tr><td align='left'><span class='pagenum'><a name="Page_87" id="Page_87">[Pg 87]</a></span></td></tr>
+<tr><td colspan="2">IV.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>100</td><td align='center'>lbs.</td></tr>
+<tr><td align='left'>Cochin Cocoanut Oil</td><td align='right'>100</td><td align='center'>"</td></tr>
+<tr><td align='left'>Castor Oil</td><td align='right'>60</td><td align='center'>"</td></tr>
+<tr><td align='left'>Glycerine</td><td align='right'>20</td><td align='center'>"</td></tr>
+<tr><td align='left'>Rosin, W. W.</td><td align='right'>20</td><td align='center'>"</td></tr>
+<tr><td align='left'>Sugar</td><td align='right'>40</td><td align='center'>"</td></tr>
+<tr><td align='left'>Water</td><td align='right'>50</td><td align='center'>"</td></tr>
+<tr><td align='left'>Soda Lye, 36 degs. B.</td><td align='right'>164</td><td align='center'>"</td></tr>
+<tr><td align='left'>Alcohol</td><td align='right'>8</td><td align='center'>gal.</td></tr>
+<tr><td colspan="2">V.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>174</td><td align='center'>lbs.</td></tr>
+<tr><td align='left'>Cocoanut Oil</td><td align='right'>114</td><td align='center'>"</td></tr>
+<tr><td align='left'>Soda Lye, 38 degs. B.</td><td align='right'>170</td><td align='center'>"</td></tr>
+<tr><td align='left'>Sugar</td><td align='right'>80</td><td align='center'>"</td></tr>
+<tr><td align='left'>Water</td><td align='right'>72</td><td align='center'>"</td></tr>
+<tr><td align='left'>Alcohol</td><td align='right'>16</td><td align='center'>gal.</td></tr>
+</table></div>
+
+
+<p>Rosin may be added in this formula up to 20 per cent. of fats used and
+the tallow cut down correspondingly.</p>
+
+
+<h3>SHAVING SOAPS.</h3>
+
+<p>The requirements of a shaving soap are somewhat different than those of
+other soaps. To be a good shaving soap the lather produced therefrom
+must be heavy, creamy, but not gummy, and remain moist when formed on
+the face. The soap itself should be of a soft consistency so as to
+readily adhere to the face when used in stick form. It should
+furthermore be neutral or nearly so to prevent the alkali from smarting
+during shaving.</p>
+
+<p>Shaving soap is made in the form of a stick, and a tablet for use in the
+shaving mug. Some shavers prefer to have the soap as a powder or cream,
+which are claimed to be more convenient methods of shaving. While a
+liquid shaving soap is not as well known because it has not yet<span class='pagenum'><a name="Page_88" id="Page_88">[Pg 88]</a></span> become
+popular, some soap for shaving is made in this form.</p>
+
+<p>Formerly shaving soap was extensively made from a charge of about 80
+parts tallow and 20 parts cocoanut oil as a boiled settled soap, but
+either making the strengthening change with potash lye or using potash
+lye in saponifying the stock and graining with salt. Soaps for shaving
+made in this manner are very unsatisfactory, as they do not produce a
+sufficiently thick or lasting lather and discolor very materially upon
+ageing. Potassium stearate forms an ideal lather for shaving, but
+readily hardens and hence needs some of the softer oils, or glycerine
+incorporated with it to form a satisfactory soap for shaving.</p>
+
+<p>The selection of materials for making a shaving soap is important. The
+tallow used should be white and of high titer. Cochin cocoanut oil is to
+be preferred to the other kinds, and the alkalis should be the best for
+technical use that can be purchased&mdash;76 per cent. caustic soda and 88-92
+per cent. caustic potash are suitable. By the use of stearic acid it is
+a simple matter to reach the neutral point which can be carefully
+approximated.</p>
+
+<p>The following are shaving soap formulae which have been found to give
+good satisfaction:</p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='center'>I.</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>360</td></tr>
+<tr><td align='left'>Stearic acid</td><td align='right'>40</td></tr>
+<tr><td align='left'>Soda lye, 41&deg; B.</td><td align='right'>147</td></tr>
+<tr><td align='left'>Potash lye, 34&deg; B.</td><td align='right'>87</td></tr>
+<tr><td align='left'>Water</td><td align='right'>32</td></tr>
+<tr><td align='left'>Gum tragacanth</td><td align='right'>1</td></tr>
+<tr><td align='center'>II.</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>282</td></tr>
+<tr><td align='left'>Cocoanut oil</td><td align='right'>60</td></tr>
+<tr><td align='left'><span class='pagenum'><a name="Page_89" id="Page_89">[Pg 89]</a></span></td></tr>
+<tr><td align='left'>Stearic acid</td><td align='left'>50</td></tr>
+<tr><td align='left'>Bayberry wax</td><td align='right'>18</td></tr>
+<tr><td align='left'>Soda lye, 41&deg; B.</td><td align='right'>147</td></tr>
+<tr><td align='left'>Potash lye, 34&deg; B.</td><td align='right'>90</td></tr>
+<tr><td align='left'>Water</td><td align='right'>32</td></tr>
+<tr><td align='center'>III.</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>400</td></tr>
+<tr><td align='left'>Cocoanut oil</td><td align='right'>176</td></tr>
+<tr><td align='left'>Stearic acid</td><td align='right'>415</td></tr>
+<tr><td align='left'>Caustic soda, 40&deg; B.</td><td align='right'>182</td></tr>
+<tr><td align='left'>Caustic potash, 38&deg; B.</td><td align='right'>108</td></tr>
+</table></div>
+
+
+<p>To proceed, first run into the crutcher the tallow, cocoanut oil and
+bayberry wax when used, and bring the temperature of the mass up to
+140&deg;-160&deg; F. by dry steam. Then add the caustic soda lye and keep on
+heat with occasional mixing until it is all taken up. When this stage is
+reached gradually add all but about 5 per cent. of the potash lye, and
+complete the saponification. This point having been reached, the heat is
+turned off; the crutcher is run and the stearic acid, previously melted
+by dry steam in a lead-lined or enameled vessel, is run in in a
+continuous stream and the crutching continued for fifteen minutes to
+half an hour. Samples are taken at this time, cooled and tested by
+alcoholic phenolphthalein solution. If too alkaline more stearic acid is
+added, if too acid more potash lye from that previously reserved. After
+each addition of lye or stearic acid the mass is crutched from 10 to 15
+minutes longer, another sample is taken, cooled and again tested. When
+the phenolphthalein shows a very light pink after several minutes, the
+soap is practically neutral, although at this point one can better judge
+by dissolving a sample in hot neutralized alcohol made by putting into
+the alcohol a few drops of phenolphthalein, and then adding weak<span class='pagenum'><a name="Page_90" id="Page_90">[Pg 90]</a></span> alkali
+drop by drop from a burette until a slight pink, not yellow, tint is
+obtained, and noting the color of the solution. The solution should show
+a very light pink when the soap is properly neutralized. When this stage
+is arrived at the gum tragacanth, previously softened in water, is
+crutched in if it is to be added. The soap is then framed, stripped in
+three or four days, dried and milled.</p>
+
+<p>The formulae as given are for shaving sticks, and do not readily press
+unless thoroughly dried. A more satisfactory result is obtained by
+adding at the mill 25 per cent. of white tallow base to obtain a
+satisfactory mug soap.</p>
+
+
+<h3>SHAVING POWDER.</h3>
+
+<p>Shaving powder differs from the soaps just described in being
+pulverized, usually adding up to 5 per cent. starch to prevent caking.
+Any of the above soaps, dried bone dry, with or without the addition of
+tallow base make a satisfactory powder for shaving.</p>
+
+
+<h3>SHAVING CREAM.</h3>
+
+<p>Shaving cream is now a very popular shaving medium due to the rapidity
+and convenience with which one can shave by the use of this product.
+Formerly shaving cream was made from the liquid oils like olive oil and
+a soft fat like lard, together with cocoanut oil. Now, however, most of
+the popular shaving creams are made from stearic acid and cocoanut oil,
+as a far superior product is obtained by the use of these substances. By
+using these a more satisfactory cream is obtained, and it is far more
+convenient to make. The lather also produced therefrom is more suitable
+for shaving, being thick, creamy and remaining moist.</p>
+
+<p>A few typical formulae for shaving creams of this type are as follows:<span class='pagenum'><a name="Page_91" id="Page_91">[Pg 91]</a></span></p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='center'>I.</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Cochin cocoanut oil</td><td align='right'>26</td></tr>
+<tr><td align='left'>Stearic acid</td><td align='right'>165</td></tr>
+<tr><td align='left'>Caustic potash lye, 50&deg; B.</td><td align='right'>69</td></tr>
+<tr><td align='left'>Glycerine C. P.</td><td align='right'>76</td></tr>
+<tr><td align='left'>Water</td><td align='right'>38</td></tr>
+<tr><td align='center'>II.</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Cochin cocoanut oil</td><td align='right'>18</td></tr>
+<tr><td align='left'>Stearic acid</td><td align='right'>73</td></tr>
+<tr><td align='left'>Caustic potash lye, 39&deg; B.</td><td align='right'>54</td></tr>
+<tr><td align='left'>Glycerine</td><td align='right'>33</td></tr>
+<tr><td align='left'>Water</td><td align='right'>27</td></tr>
+<tr><td align='center'>III.</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Cochin cocoanut oil</td><td align='right'>18</td></tr>
+<tr><td align='left'>Stearic acid</td><td align='right'>73</td></tr>
+<tr><td align='left'>Caustic potash lye, 39&deg; B.</td><td align='right'>54</td></tr>
+<tr><td align='left'>Glycerine</td><td align='right'>20</td></tr>
+<tr><td align='left'>Water</td><td align='right'>40</td></tr>
+<tr><td align='center'>and</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Stearic acid</td><td align='right'>60</td></tr>
+<tr><td align='left'>Glycerine C. P.</td><td align='right'>85</td></tr>
+<tr><td align='left'>Water</td><td align='right'>165</td></tr>
+<tr><td align='left'>Sodium carbonate</td><td align='right'>50</td></tr>
+<tr><td align='left'>Borax</td><td align='right'>1</td></tr>
+</table></div>
+
+<p>To make a shaving cream by Formula I or II, the cocoanut oil and
+glycerine are first put into a suitable mixing apparatus or crutcher,
+and heated to 120&deg; F. A part or all the potash lye is then added and the
+cocoanut oil<span class='pagenum'><a name="Page_92" id="Page_92">[Pg 92]</a></span> saponified. The rest of the potash lye and the water are
+then added, and with the mixer running the stearic acid, previously
+melted in a lead-lined or enameled vessel, is then poured in in a stream
+and the mass stirred until smooth, care being exercised not to aerate it
+too much. The cream is then tested for alkalinity, the best method being
+by that described under shaving soap, in which the sample is dissolved
+in alcohol. Because of the large quantity of water present,
+phenolphthalein is unsatisfactory, as dissociation of the soap may show
+a pink indication in spite of the fact the mass is on the acid side. For
+a quick method of testing the bite on the tongue is a satisfactory
+criterion. If a cooled sample bites the tongue more stearic acid is
+added until there is a 3% excess of this. When the proper neutralization
+has taken place the cream is perfumed and framed in a special frame, or
+it may be allowed to cool in the mixer and perfumed the next day. When
+cool the cream is strained, or put through an ointment mill, after which
+it is ready to fill into tubes.</p>
+
+<p>The procedure for the first part of Formula III is the same as that just
+given. The second part of the formula is made the same as a vanishing
+cream for toilet purposes. To make this, first melt the stearic acid as
+already directed. Dissolve the sodium carbonate and borax in water and
+when dissolved add the glycerine and stir. Then heat this solution to
+about 100&deg;-120&deg; F. and while stirring in a suitable mixing machine into
+which this solution has been poured after being heated, or better still
+in which it has been heated by dry steam, add the stearic acid. Continue
+mixing until smooth and then allow to cool, or run into frames to cool.</p>
+
+<p>When the shaving cream and vanishing cream are both cool, they are mixed
+in the proportion of one of the former to two of the latter. It is
+claimed that in thus<span class='pagenum'><a name="Page_93" id="Page_93">[Pg 93]</a></span> making a shaving cream a smoother product is
+obtained, although it may be said that the vanishing cream is merely a
+soft soap and the ultimate result is the same as though the various
+ingredients were added in one operation, rather than making two separate
+products and then mixing them, thereby considerably increasing the cost
+of manufacture.</p>
+
+
+<h3>PUMICE OR SAND SOAPS.</h3>
+
+<p>Pumice and sand are at times added to soap to aid in the removal of dirt
+in cleansing the hands. In some cases these soaps are made in the form
+of a cake, in others they are sold in cans in the form of a paste.</p>
+
+<p>A hand paste is usually made by merely dissolving ordinary tallow base
+in two or three times its weight of hot water and mixing in the desired
+quantity of pumice or sand and in some instances adding a little
+glycerine to keep it soft or a solvent of some kind for grease. It may
+also be made by directly incorporating any of these in a potash soap.</p>
+
+<p>A cold made or semi-boiled cocoanut or palm kernel oil soap is the base
+used to add the pumice or sand to in making a cake soap of this sort.
+The following formulae serve as a guide for these soaps.</p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td colspan="2">I.</td></tr>
+<tr><td align='left'>Palm Kernel or Ceylon Cocoanut Oil</td><td align='right'>705</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Pumice (Powdered)</td><td align='right'>281</td><td align='center'>"</td></tr>
+<tr><td align='left'>Soda Lye, 38&deg; B.</td><td align='right'>378</td><td align='center'>"</td></tr>
+<tr><td colspan="2">II.</td></tr>
+<tr><td align='left'>Cocoanut Oil</td><td align='right'>100</td><td align='center'>"</td></tr>
+<tr><td align='left'>Soda Lye, 38&deg; B.</td><td align='right'>55</td><td align='center'>"</td></tr>
+<tr><td align='left'>Water</td><td align='right'>6</td><td align='center'>"</td></tr>
+<tr><td align='left'>Silver Sand (fine)</td><td align='right'>60</td><td align='center'>"</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_94" id="Page_94">[Pg 94]</a></span></p>
+
+<p>To proceed place the oil in a crutcher and heat to 140&deg; F. Sift in the
+pumice and mix thoroughly. The lye is then added which causes a curdling
+of the grain. The stirring is continued until the grain closes and the
+soap is smooth, after which the desired perfume is added and the soap
+dropped into a frame and crutched by hand. When the soap is set, it is
+slabbed, cut into cakes, dried slightly and pressed.</p>
+
+
+<h3>LIQUID SOAPS.</h3>
+
+<p>Liquid soaps are merely solutions of a potash soap, usually cocoanut oil
+soap, although corn oil is used to make a cheap soap. One of the
+difficulties encountered in liquid soap is to keep it clear. At a low
+temperature a sediment is often formed, but this can be overcome by the
+use of sugar and filtering the soap through a filter press at a low
+temperature. In order to prevent the soap from freezing, it is necessary
+to lower the freezing point by the addition of glycerine or alcohol.</p>
+
+<p>To make liquid soap by any of the formulae given below, the oil is first
+run into a jacketed kettle with a stirring device, and heated to about
+120&deg; F. The potash lye is then added and the oil saponified. When the
+saponification takes place, especially when cocoanut oil is used, the
+mass swells rapidly and may foam over the sides of the kettle unless
+water is used to check this, or a kettle of about four to five times the
+capacity of the total charge of soap is used. When the saponification
+has occurred, the sugar, borax and glycerine are added, the water run in
+and the mixture stirred until the soap is thoroughly dissolved. Heat
+aids materially in dissolving the soap. The soap is then allowed to cool
+and if color or perfume is to be added this is stirred in, after which
+the soap is cooled and filtered or else run directly into barrels.<span class='pagenum'><a name="Page_95" id="Page_95">[Pg 95]</a></span></p>
+
+<p>Tallow is not suitable for making a clear liquid soap since it is too
+high in stearine which when formed into the stearate makes an opaque
+solution. The formulae herewith given have been found to give good
+practical results.</p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='center'>I.</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Cocoanut oil</td><td align='right'>130</td></tr>
+<tr><td align='left'>Caustic potash lye, 28&deg; B.</td><td align='right'>135</td></tr>
+<tr><td align='left'>Sugar</td><td align='right'>72</td></tr>
+<tr><td align='left'>Borax</td><td align='right'>2</td></tr>
+<tr><td align='left'>Water</td><td align='right'>267</td></tr>
+<tr><td align='center'>II.</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Corn oil</td><td align='right'>130</td></tr>
+<tr><td align='left'>Caustic potash lye, 26&deg; B.</td><td align='right'>135</td></tr>
+<tr><td align='left'>Sugar</td><td align='right'>72</td></tr>
+<tr><td align='left'>Borax</td><td align='right'>2</td></tr>
+<tr><td align='left'>Water</td><td align='right'>267</td></tr>
+<tr><td align='center'>III.</td><td align='right'>lbs.</td></tr>
+<tr><td align='left'>Cocoanut oil</td><td align='right'>100</td></tr>
+<tr><td align='left'>Caustic potash lye, 28&deg; B.</td><td align='right'>102</td></tr>
+<tr><td align='left'>Glycerine</td><td align='right'>100</td></tr>
+<tr><td align='left'>Sugar</td><td align='right'>70</td></tr>
+<tr><td align='left'>Water</td><td align='right'>833</td></tr>
+</table></div>
+
+<p>Formulae I and II contain about 20 per cent. fatty acids. It is
+possible, of course, to either increase or decrease the percentage of
+fatty acid by varying the amount of water. The water used in making
+liquid soaps, of course, should be soft, for hard water forms insoluble
+soaps which precipitate and cause a sediment.<span class='pagenum'><a name="Page_96" id="Page_96">[Pg 96]</a></span></p>
+
+
+<h3>USE OF HARDENED OILS IN TOILET SOAPS.</h3>
+
+<p>While the introduction of the hydrogenation of oils is a decided advance
+in the production of suitable cheaper oils for soap making,
+comparatively little hardened oil is employed for soap making in America
+up to the present time. In Europe, however, considerable advance has
+been made by the use of such oils for manufacturing soap therefrom and a
+number of plants turn out large quantities of hydrogenated oils for soap
+making as well as for edible purposes. Recently a company has been
+formed in this country for hardening oils and it is very probable that
+the future will see this material extensively used in our own country,
+as these appear to be the one present hope of the soap manufacturer as a
+check on the ever increasing cost of fats and oils now used in making
+soap.</p>
+
+<p>It is an unfortunate condition that hydrogenated oils produced abroad
+are sold under names which give absolutely no indication as to the oil
+which has been hardened. The softer and cheaper oils like fish oil,
+linseed oil, cottonseed oil, etc., are generally hardened for soap
+manufacture to different degrees of hardness. While it is impossible to
+definitely state just what products as Candelite, Talgol, Krutolin or
+several other coined names of hardened oils are, various investigators
+have experimented with them as to their adaptability for producing
+toilet soaps and found that suitable toilet soaps may be made from them.
+While many objections were at first met with concerning soaps made from
+these products, as to their unsatisfactory saponification, the poor
+lathering quality of the soaps and their odor and consequent difficulty
+in perfuming, the results of most investigators along these lines
+indicate that these in many cases were due to prejudice against or
+unfamiliarity with handling oils of this type for soap making.</p>
+
+<p>In manufacturing soap from hardened oils it is usually<span class='pagenum'><a name="Page_97" id="Page_97">[Pg 97]</a></span> necessary to
+incorporate with the charge lard, tallow, tallow oil or some other soft
+oil of this nature. Satisfactory bases for toilet soaps, made as boiled
+settled soap by the use of Talgol (undoubtedly hardened fish oil), are
+said to be made by the formulae<a name="FNanchor_10_10" id="FNanchor_10_10"></a><a href="#Footnote_10_10" class="fnanchor">[10]</a> below.</p>
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td colspan="2">I.</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>45</td><td align='center'>parts</td></tr>
+<tr><td align='left'>Talgol</td><td align='right'>40</td><td align='center'>"</td></tr>
+<tr><td align='left'>Cocoanut Oil</td><td align='right'>15</td><td align='center'>"</td></tr>
+<tr><td colspan="2">II.</td></tr>
+<tr><td align='left'>Cocoanut Oil (Ceylon)</td><td align='right'>6</td><td align='center'>"</td></tr>
+<tr><td align='left'>Tallow</td><td align='right'>12</td><td align='center'>"</td></tr>
+<tr><td align='left'>Talgol, Extra</td><td align='right'>12</td><td align='center'>"</td></tr>
+</table></div>
+
+
+<p>The method of boiling a soap of this type does not differ materially
+from that of making settled tallow soap base. The soap itself has a
+different odor than a straight tallow base, but is said to make a very
+satisfactory soap for milling and to be of good appearance.</p>
+
+<p>Satisfactory transparent soaps are made from the hardened oil Candelite,
+which replaces the tallow in transparent soap formulae such as have
+already been given in the section under "Transparent Soaps." The method
+of manufacturing a soap by the use of this product varies in no way from
+the usual method employed for making these soaps.</p>
+
+<p>Since hydrogenated oils are high in stearine, their use in shaving soaps
+is a decided advantage. It has previously been pointed out that
+potassium stearate forms an ideal lather for shaving, and in the
+hydrogenating process the olein is converted to stearine. Thus a
+hardened<span class='pagenum'><a name="Page_98" id="Page_98">[Pg 98]</a></span> oil is advantageous in a shaving soap. As an example of a cold
+made soap for shaving the following may be taken.<a name="FNanchor_11_11" id="FNanchor_11_11"></a><a href="#Footnote_11_11" class="fnanchor">[11]</a></p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Talgol Extra</td><td align='left'>50 lbs.</td></tr>
+<tr><td align='left'>Cocoanut Oil</td><td align='left'>10 "</td></tr>
+<tr><td align='left'>Lard</td><td align='left'>10 "</td></tr>
+<tr><td align='left'>Soda Lye, 38&deg; B.</td><td align='left'>20 "</td></tr>
+<tr><td align='left'>Potash Lye, 37&deg; B.</td><td align='left'>21 "</td></tr>
+</table></div>
+
+<p>This soap may be made in a crutcher by the method generally used in
+making soap by the cold process.</p>
+
+
+<h3>TEXTILE SOAPS.</h3>
+
+<p>Soap is a very important product to every branch of the textile
+industry. For woolen fabrics it is used for scouring, fulling and
+throwing the wool; in the silk industry it is necessary for degumming
+the raw silk, as well as for dyeing; in the cotton mills it is used to
+finish cotton cloth and to some extent in bleaching; it is, furthermore,
+employed in a number of ways in the manufacture of linen. Large
+quantities of soap are thus consumed in an industry of so great an
+extent and the requirements necessitate different soaps for the
+different operations. We will, therefore, consider these in detail.</p>
+
+
+<h3>SCOURING AND FULLING SOAPS FOR WOOL.</h3>
+
+<p>The soaps used to scour wool and for fulling the woven cloth are usually
+made as cheaply as possible. They are, however, generally pure soaps, as
+filling material such as sodium silicate does not readily rinse out of
+the wool and if used at all must be added very sparingly. Both cold made
+and boiled settled soaps are made for this purpose. The soap is
+generally sold in barrels, hence is run directly to these from the
+crutcher or soap kettle. As cold made soaps the following serve for wool
+scouring or fulling.<span class='pagenum'><a name="Page_99" id="Page_99">[Pg 99]</a></span></p>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td colspan="2">I.</td></tr>
+<tr><td align='left'>Palm Oil</td><td align='left'>200 lbs.</td></tr>
+<tr><td align='left'>Bone Grease</td><td align='left'>460 "</td></tr>
+<tr><td align='left'>Soda Lye, 36&deg; B.</td><td align='left'>357 "</td></tr>
+<tr><td align='left'>Water</td><td align='left'>113 "</td></tr>
+<tr><td align='left'>Soda Ash</td><td align='left'>50 "</td></tr>
+<tr><td align='left'>Citronella</td><td align='left'>2 "</td></tr>
+<tr><td colspan="2">II.</td></tr>
+<tr><td align='left'>Palm Oil (Calabar, unbleached)</td><td align='left'>155 "</td></tr>
+<tr><td align='left'>House Grease</td><td align='left'>360 "</td></tr>
+<tr><td align='left'>Soda Lye, 36&deg; B.</td><td align='left'>324 "</td></tr>
+<tr><td align='left'>Water</td><td align='left'>268 "</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='left'>83 "</td></tr>
+<tr><td colspan="2">III.</td></tr>
+<tr><td align='left'>House Grease</td><td align='left'>185 "</td></tr>
+<tr><td align='left'>Palm Oil (unbleached)</td><td align='left'>309 "</td></tr>
+<tr><td align='left'>Soda Lye, 36&deg; B.</td><td align='left'>309 "</td></tr>
+<tr><td align='left'>Water</td><td align='left'>391 "</td></tr>
+<tr><td align='left'>Soda Ash</td><td align='left'>70 "</td></tr>
+<tr><td align='left'>Sodium Silicate</td><td align='left'>60 "</td></tr>
+<tr><td align='left'>Corn Starch</td><td align='left'>10 "</td></tr>
+</table></div>
+
+<p>These soaps are made in a crutcher by the usual process for cold-made
+soaps, crutched until smooth, dropped into a barrel and crutched by hand
+the next day or just before cooling.</p>
+
+<p>As a settled soap for these operations the following charge is typical:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Palm Oil</td><td align='left'>34</td><td align='left'> parts</td></tr>
+<tr><td align='left'>Cottonseed foots or its equivalent in fatty acids</td><td align='left'>33</td><td align='left'>"</td></tr>
+<tr><td align='left'>Rosin</td><td align='left'>10</td><td align='left'>"</td></tr>
+<tr><td align='left'>House Grease</td><td align='left'>23</td><td align='left'>"</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_100" id="Page_100">[Pg 100]</a></span></p>
+
+<p>The method of boiling such a soap is the same as for any settled soap up
+to the strengthening change. When this stage is reached, sufficient lye
+is added to strengthen the kettle strongly. It is then boiled down with
+closed steam on salt brine or "pickle" until a sample of the lye taken
+from the bottom stands at 16&deg;-22&deg; B. The soap is then run into barrels
+and after standing therein for a day is hand crutched until cool to
+prevent streaking of the soap.</p>
+
+<p>Besides a soap of this type a settled tallow chip soap is used.</p>
+
+
+<h3>WOOL THROWER'S SOAP.</h3>
+
+<p>Soaps for wool throwing are sometimes made from olive oil foots but
+these are often objected to because of the sulphur-like odor conveyed to
+the cloth due to the method by which this oil is extracted with carbon
+disulphide. A potash soap hardened somewhat with soda is also used. As a
+formula for a suitable soap of this type this may be given.</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Olive Oil Foots</td><td align='left'>12 parts</td></tr>
+<tr><td align='left'>Corn Oil</td><td align='left'>46 "</td></tr>
+<tr><td align='left'>House Grease</td><td align='left'>20 "</td></tr>
+<tr><td align='left'>Soda Lye, 36&deg; B.</td><td align='left'>3 "</td></tr>
+<tr><td align='left'>Potassium Carbonate (dry)</td><td align='left'>5-3/4 "</td></tr>
+<tr><td align='left'>Potassium Hydrate (solid)</td><td align='left'>23 "</td></tr>
+</table></div>
+
+
+<p>This soap is made as a "run" soap by the general directions already
+given for a soap thus made. The kettle is boiled with open and closed
+steam, adding water very slowly and aiming to obtain a 220-225 per cent.
+yield or fatty acid content of the finished soap of 46 per cent. When
+the soap is finished a sample cooled on a plate of glass should be
+neither slippery or short, but should string slightly. The finished soap
+is run directly into barrels.<span class='pagenum'><a name="Page_101" id="Page_101">[Pg 101]</a></span></p>
+
+<p>A soap for wool throwing by the semi-boiled process may be made from
+olive oil foots in a crutcher thus:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Olive Oil Foots</td><td align='left'>600 lbs.</td></tr>
+<tr><td align='left'>Potash Lye, 20&deg; B.</td><td align='left'>660 "</td></tr>
+</table></div>
+
+<p>The oil is heated to 180&deg; F., the lye added and the mass stirred until
+it bunches, when it is dropped into barrels.</p>
+
+
+<h3>WORSTED FINISHING SOAPS.</h3>
+
+<p>For the finishing of worsted cloth soaps high in cocoanut oil or palm
+kernel oil are preferred. These soaps are finished very neutral, being
+made as settled soaps, but given an extra wash change after
+strengthening strongly. They are then finished as usual and run into
+barrels. If framed too hot, the high percentage of cocoanut oil causes
+mottling, which is prevented by crutching by hand until the temperature
+of the soap is 140&deg;-145&deg; F. Some typical charges, all of which are
+saponified with soda lye, follow:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td colspan="2">I.</td></tr>
+<tr><td align='left'>Palm Kernel Oil</td><td align='left'>60 parts</td></tr>
+<tr><td align='left'>Corn Oil</td><td align='left'>40 "</td></tr>
+<tr><td colspan="2">II.</td></tr>
+<tr><td align='left'>Palm Kernel Oil</td><td align='left'>30 "</td></tr>
+<tr><td align='left'>Red Oil (single pressed)</td><td align='left'>70 "</td></tr>
+<tr><td colspan="2">III.</td></tr>
+<tr><td align='left'>Red Oil</td><td align='left'>33-1/3 "</td></tr>
+<tr><td align='left'>Corn Oil</td><td align='left'>33-1/3 "</td></tr>
+<tr><td align='left'>Cocoanut Oil or Palm Kernel Oil</td><td align='left'>33-1/3 "</td></tr>
+</table></div>
+
+
+
+<h3>SOAPS USED IN THE SILK INDUSTRY.</h3>
+
+<p>Soap is used to a very large extent in silk mills, both for<span class='pagenum'><a name="Page_102" id="Page_102">[Pg 102]</a></span> degumming
+the raw silk and in silk dyeing. Raw silk consists of the true silk
+fibre known as fibroin and a gummy coating, sericin, which dulls the
+lustre of the silk unless removed. For this purpose a slightly alkaline
+olive oil foots soap is best adapted, although palm oil and peanut oil
+soaps are sometimes used, as well as soaps made from a combination of
+house grease to the extent of 30 per cent., together with red oil or
+straight olein soaps, both of which are artificially colored green. In
+using house grease, if 30 per cent. is exceeded in combination with red
+oil, the titer is raised to such an extent that the soap does not
+readily rinse from the silk nor dissolve readily. They are also not
+advisable because they impart a disagreeable odor to the silk.</p>
+
+<p>To make a soap for this purpose from olive oil foots it is made as a
+settled soap, care being taken to thoroughly boil the mass on the
+saponification change in the closed state to assure proper
+saponification. The kettle is usually grained with lye and given a good
+wash change to remove the excess strength. The change previous to the
+finish should not be too heavy or too large a nigre results. The lighter
+the grain is, the better the finished kettle is. A yield of 150 per
+cent. is usually obtained. This soap is generally run to a frame,
+slabbed upon cooling and packed directly into wooden cases.</p>
+
+<p>For silk dyeing the above soap is suitable, although any well-made soap
+of good odor and not rancid is useable. While soap alone is often used
+in the bath for silk dyeing, certain dyestuffs require the addition of
+acetic or sulphuric acid, which sets free the fatty acids. If these be
+of bad odor it is taken up by the silk and is difficult to remove. The
+most generally used soaps are the just mentioned olive foots soap or a
+soap made from a good grade red oil.</p>
+
+<p>Both kinds are extensively used.<span class='pagenum'><a name="Page_103" id="Page_103">[Pg 103]</a></span></p>
+
+
+<h3>SOAPS USED FOR COTTON GOODS.</h3>
+
+<p>In the manufacture of cotton goods, as compared to the wool and silk
+industries, very much less soap is used and it is only applied to the
+finished fabric either to clean the cloth preparatory to dyeing or to
+aid in dyeing with certain colors. It is also used in calico printing.
+For cleansing the cloth ordinary chip soap is suitable although a more
+alkaline soap finished as a curd soap is an advantage in that the free
+alkali contained therein aids in removing the dirt and has no harmful
+effect on the cotton. For dyeing cotton goods or to brighten certain
+colors after dyeing an olive oil foots soap is most generally employed.
+In calico printing soap is used to wash and clear the cloth after
+printing. A soap for this purpose should be easily soluble in water and
+contain no free alkali, rosin or filler. The best soaps for use in
+calico printing are either an olive oil foots soap or an olein soap.</p>
+
+
+<h3>SULPHONATED OILS.</h3>
+
+<p>While sulphonated oils are not used to any great extent in the
+manufacture of soap, they are used very largely in the dyeing and
+printing of turkey and alizarine reds on cotton as well as other colors.
+Just what action these oils have is not known. Turkey red oil or
+sulphonated castor oil is the best known sulphonated oil.</p>
+
+<p>The process of making these oils is simple. The equipment necessary is a
+wooden tank or barrel of suitable capacity, approximately two and a half
+times the amount of oil to be treated. There are furthermore required
+other tanks or vessels to hold the solutions used such as caustic soda,
+ammonia and acid. The tank to be used for the preparation of sulphonated
+oil should be provided with a valve at the bottom of the tank and a
+gauge to measure the quantity of liquid therein.<span class='pagenum'><a name="Page_104" id="Page_104">[Pg 104]</a></span></p>
+
+<p>The process is carried out as follows:</p>
+
+<p>Three hundred pounds of castor oil are placed in the tank and 80 pounds
+at 66 deg. B. sulphuric acid are weighed out in another vessel. The acid
+is run into the tank containing the oil in a very thin stream while the
+oil is well stirred. At no time should the temperature exceed 40 deg. C.
+This operation should consume at least an hour and stirring should be
+continued half an hour longer to insure the thorough mixing of the oil
+with the acid. The mass is then allowed to settle for 24 hours, after
+which 40 gallons of water are added and the mixture stirred until it has
+a uniform creamy color indicating no dark streaks. This mixing process
+should be carefully carried out and when completed allowed to settle 36
+hours. At this point the mass will have separated into two layers, the
+lower layer consisting of a water solution of acid and the upper layer
+of oil. The former is run out through the valve located at the bottom of
+the tank. Another wash may now be given or dispensed with as desired. In
+this wash the addition of salt or sodium sulphate at the rate of 1-1/2
+pounds per gallon of water is advisable. A 24 deg. B. caustic soda
+solution is prepared and added slowly to the acidified oil with constant
+stirring. The mass first turns creamy, then becomes streaked, increasing
+in streaks as the caustic solution is poured in, and finally becomes
+clear and transparent. Water is now added to bring the volume to 75
+gallons. The oil is now milky in appearance, but the addition of a
+little more soda solution restores the transparency.</p>
+
+<p>In some cases ammonia is used in addition to caustic soda in
+neutralizing the oil. Three-fourths of the amount of caustic soda
+required to complete the neutralization is first added and then the
+neutralization is completed with a one to one liquid ammonia and water
+solution.</p>
+
+<div class="footnotes"><h3>FOOTNOTES:</h3>
+
+<div class="footnote"><p><a name="Footnote_9_9" id="Footnote_9_9"></a><a href="#FNanchor_9_9"><span class="label">[9]</span></a> Seifensieder Ztg., 40, 47, 1266 (1913).</p></div>
+
+<div class="footnote"><p><a name="Footnote_10_10" id="Footnote_10_10"></a><a href="#FNanchor_10_10"><span class="label">[10]</span></a>
+Seifensieder Ztg. (1913), p. 334 and 338.<br />
+<span style="margin-left: 2em;">"&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"&nbsp;&nbsp;&nbsp;(1912), p. 1229 and 1257.</span>
+</p></div>
+
+<div class="footnote"><p><a name="Footnote_11_11" id="Footnote_11_11"></a><a href="#FNanchor_11_11"><span class="label">[11]</span></a> Seifensieder Ztg. (1912), p. 954.</p></div>
+</div>
+
+
+<hr style="width: 65%;" /><p><span class='pagenum'><a name="Page_105" id="Page_105">[Pg 105]</a></span></p>
+<h2>CHAPTER V</h2>
+
+<h3>Glycerine Recovery.</h3>
+
+
+<p>The recovery of glycerine is very closely allied with the soap-making
+industry, because glycerine is the very valuable by-product obtained in
+the saponification of oils and fats. No soap plant is, therefore, fully
+equipped unless it has some method whereby the glycerine is recovered
+and the importance of recovering this product cannot be too strongly
+emphasized.</p>
+
+<p>It has already been pointed out that neutral fats or the glycerides are
+a combination of fatty acid with glycerine. These are split apart in the
+process of saponification. While by the term <i>saponification</i> as used in
+soap making it is inferred that this is the combination of caustic
+alkalis with the fatty acids to form soap, this term is by no means
+limited to this method of saponification, as there are various other
+methods of saponifying a fat. The chemical definition of saponification
+is the conversion of an ester, of which glycerides are merely a certain
+type, into an alcohol and an acid or a salt of this acid. Thus, if we
+use caustic alkali as our saponifying agent for a fat or oil, we obtain
+the sodium or potassium salt of the higher fatty acids or soap and the
+alcohol, glycerine. On the other hand, if we use a mineral acid as the
+saponifying agent, we obtain the fatty acids themselves in addition to
+glycerine. While the former is by far the most generally employed for
+making soap, other processes consist in saponifying the fats by some
+method other than caustic alkalis and then converting the fatty acids
+into soap by either neutralizing them with sodium or potassium carbonate
+or hydrate.</p>
+
+<p>It is important to again point out here that fats and oils<span class='pagenum'><a name="Page_106" id="Page_106">[Pg 106]</a></span> develop free
+fatty acid of themselves and that the development of this acid
+represents a loss in glycerine. The selection of an oil or fat for soap
+making should therefore to a large extent be judged as to its
+adaptability by the free fatty acid content, as the higher this content
+is, the greater is the loss in the glycerine eventually obtained.
+Glycerine often represents the only profit to a soap manufacturer. It is
+indeed necessary to determine the percentage of free fatty acid before
+purchasing a lot of stock to be made into soap.</p>
+
+<p>In taking up the question of glycerine recovery we will consider the
+various methods thus:</p>
+
+<p>1. Where the glycerine is obtained from spent lye by saponifying the
+fats or oils with caustic alkali.</p>
+
+<p>2. Where the glycerine is obtained by saponifying the fats or oils by
+some other method than the above, of which there are the following:</p>
+
+<p>
+(a) Twitchell process.<br />
+(b) Saponification by lime in autoclave.<br />
+(c) Saponification by acid.<br />
+(d) Saponification by water in autoclave.<br />
+(e) Fermentative (Enzymes).<br />
+(f) Krebitz process.
+</p>
+
+
+<h3>RECOVERY OF GLYCERINE FROM SPENT LYE.</h3>
+
+<p>The spent lye obtained from the glycerine changes in making soap varies
+greatly, the quality depending upon the stock saponified and the soap
+maker's care in handling the operation. No two lyes run exactly alike as
+to proportion of the various ingredients, although they are all similar
+in containing the same substances either in solution or suspension.
+Spent lye is a water solution of mainly glycerine, free alkali either as
+caustic alkali or carbonate and salt, including sodium sulfate, but
+furthermore contains some soap and albuminous matter either in solution
+or<span class='pagenum'><a name="Page_107" id="Page_107">[Pg 107]</a></span> suspension. Upon standing in the storage tank the greater part of
+the soap usually separates when the lye cools. In order to assure the
+greatest economical yield of glycerine by saponifying a fat with caustic
+soda it is necessary to obtain a proportion of three parts of water to
+every part of fat made into soap. Test runs have shown that this is the
+proper proportion and that it is not economical to greatly exceed this
+amount, and if a much less proportion is used the full yield of
+glycerine is not obtained.</p>
+
+<p>The spent lyes contain varying amounts of glycerine, the first change
+being richest in glycerine content, and this being reduced in the
+subsequent changes. If the lyes always run high in glycerine it is an
+indication that it is not all being obtained. The usual percentage is
+from 0.5% to 5% or even more, although the average is somewhere around
+2% to 3%. The lye as it comes from the kettle should not contain any
+more than 0.5% to 0.6% of free alkali calculated as sodium carbonate,
+Na<sub>2</sub>CO<sub>3</sub>. If the proportion is higher than this, it shows that the
+saponification has been conducted with too high a proportion of alkali,
+a condition which should be corrected in the kettle room. An excess of
+free alkali does not interfere to any great extent with the successful
+recovery of the glycerine, but is a waste of both alkali and the acid
+used in neutralizing this. It is, therefore, more economical to run a
+strong lye over fresh stock and neutralize the alkali thus, rather than
+treating the lye for glycerine recovery.</p>
+
+<p>Before the spent lye can be run into the evaporator it is necessary to
+remove the albuminous impurities and soap and to neutralize the excess
+alkali to between exactly neutral and 0.02% alkalinity. The lye should
+never be fed into the evaporator in the acid condition.</p>
+
+<p>In order to treat the spent lyes for evaporation, they are first allowed
+to cool in the storage tank, after which any<span class='pagenum'><a name="Page_108" id="Page_108">[Pg 108]</a></span> soap which may have
+separated is skimmed off and returned to the soap kettle. This lye is
+then pumped to the treatment tank, an ordinary tank equipped with some
+method of agitating the liquor, either by a mechanical stirrer, steam
+blower or compressed air, until it is about two feet from the top.</p>
+
+<p>After the lye has been skimmed off it is thoroughly agitated and a
+sample taken. The amount of lye in the tank is then calculated. Spent
+lye is about 1.09 times heavier than water, or weighs about 9 pounds to
+the gallon. While the sample is being tested for alkalinity it is
+advisable to add sulfate of alumina, which may be dissolving while the
+sample is being titrated. This substance should be added in the
+proportion of anywhere from 6 to 14 pounds per thousand pounds of lye,
+depending upon the amount of impurities contained therein. For a clean
+lye six pounds per thousand is sufficient, but for an impure lye a
+greater quantity is necessary. The sulfate of alumina used should be
+free from arsenic and sulfides and should contain a minimum amount of
+grit (silica), as grit reduces the life of the pump valves. This may be
+estimated with sufficient accuracy by rubbing the filtered-off portions,
+insoluble in water between the fingers and a plate of glass. The object
+of adding the sulfate of alumina is to transform the soap contained in
+the lye into the insoluble aluminum soaps, and at the same time to
+coagulate the albuminous impurities. It must be remembered that the
+sulfate of alumina is added only for the fresh lye put into the tank.
+Thus if there were 10,000 pounds of lye in the treating tank when the
+fresh lye was run in, and 50,000 pounds when the tank is filled, adding
+nine pounds of sulfate of alumina per thousand of lye, only 360 pounds
+would be added or enough for 40,000 pounds. Sulfate of alumina
+neutralizes one-third of its weight of caustic.<span class='pagenum'><a name="Page_109" id="Page_109">[Pg 109]</a></span></p>
+
+<p>To determine the alkali in the sample, 10 cubic centimeters are pipetted
+into a beaker, a little distilled water added, then 3 or 4 drops of
+phenolphthalein indicator. From a burette, quarter normal (N/4) sulfuric
+acid is added until the pink color is just discharged. When this point
+is reached 4 to 5 c. c. more of acid are added and the solution is
+boiled to expel the carbon dioxide. Should the solution turn pink, it is
+necessary to add more acid. After having boiled for 3 to 4 minutes, N/4
+caustic soda is added until the pink color just returns and the amount
+of caustic soda used is read on the burette. The difference between the
+number of cubic centimeters of N/4 sulfuric acid and N/4 caustic soda
+gives the amount of alkali in the sample. By using a 10 c. c. sample and
+N/4 sulfuric acid and N/4 caustic soda each c. c. obtained by the
+difference of these two solutions is equal to one-tenth of one per cent.
+(0.1%) of the total alkali in the lye. As an example, say we first used
+7.7 c. c. of N/4 sulfuric acid to just discharge the pink, then added 4
+c. c. more, or 11.7 c. c. in total. After boiling it required 5.3 c. c.
+to bring back a slight pink, the total alkalinity would be 11.7 c. c. -
+5.3 c. c. = 6.4 c. c., or 0.64% total alkali in the lye in terms of
+caustic soda. If there were 40,000 pounds of lye to be treated then we
+should have to neutralize:</p>
+
+<p>40,000 &times; .0064 = 256 lbs. alkali. Since sulfate of alumina neutralizes
+one-third of its weight in caustic, and there are say 9 lbs. of this
+added per thousand pounds of lye we would add</p>
+
+<p>40,000 &times; 9 = 360 lbs. of sulfate of alumina. This would neutralize 360 &times;
+1/3 = 120 lbs of alkali. There are then 256 - 120 = 136 lbs. of alkali
+still to be neutralized. If 60&deg; B. sulfuric acid is used it requires
+about 1.54 lbs. of acid to one pound of caustic. Therefore to neutralize
+the caustic soda remaining it requires:<span class='pagenum'><a name="Page_110" id="Page_110">[Pg 110]</a></span></p>
+
+<p>136 &times; 1.54 = 209.44 lbs. 60&deg; B. sulfuric acid to neutralize the total
+alkali in the 40,000 pounds of spent lye.</p>
+
+<p>The acid is added and the lye well stirred, after which another sample
+is taken and again titrated as before. From this titration the amount of
+acid to be added is again calculated and more acid is added if
+necessary. Should too much acid have been added, caustic soda solution
+is added until the lye is between exactly neutral and 0.02% alkaline.
+The filtered lyes at this stage have a slight yellowish cast.</p>
+
+<p>To be sure that the lyes are treated correctly the precipitation test is
+advisable. To carry this out filter about 50 c. c. of the treated lye
+and divide into two portions in a test tube. To one portion add ammonia
+drop by drop. If a cloudiness develops upon shaking, more alkali is
+added to the lye in the tank. To the other portion add a few drops of 1
+to 5 sulfuric acid and shake the test tube. If a precipitate develops or
+the solution clouds, more acid is needed. When the lyes are treated
+right no cloudiness should develop either upon adding ammonia or the
+dilute acid.</p>
+
+<p>The properly treated lye is then run through the filter press while
+slightly warm and the filtered lye is fed to the evaporator from the
+filtered lye tank. The lye coming from the filter press should be clear
+and have a slight yellowish cast. As the pressure increases it is
+necessary to clean the press or some of the press cake will pass through
+the cloths. Where sodium silicate is used as a filler, the silicate
+scrap should never be returned to the soap kettle until the glycerine
+lyes have been withdrawn. This practice of some soapmakers is to be
+strongly censured, as it causes decided difficulty in filtering the lye,
+since during the treatment of the lye, free silicic acid in colloidal
+form is produced by the decomposition of the sodium silicate by acid.
+This often prevents filtering the treated lye even at<span class='pagenum'><a name="Page_111" id="Page_111">[Pg 111]</a></span> excess pressure
+and at its best retards the filtering.</p>
+
+<p>As to the filter press cake, this may be best thrown away in a small
+factory. Where, however, the output of glycerine is very large it pays
+to recover both the fatty acids and alumina in the press cakes.</p>
+
+<p>In some cases, especially when the lyes are very dirty and the total
+residue in the crude glycerine runs high, for which there is a penalty
+usually attached, a double filtration of the lye is advisable. This is
+carried out by first making the lye slightly acid in reaction by the
+addition of alum and acid, then filtering. This filtered lye is then
+neutralized to the proper point with caustic, as already described, and
+passed through the filter press again.</p>
+
+<p>While in the method of treating the lyes as given sulfuric acid is used
+for neutralizing, some operators prefer to use hydrochloric acid, as
+this forms sodium chloride or common salt, whereas sulfuric acid forms
+sodium sulfate, having 3/5 the graining power of salt, which eventually
+renders the salt useless for graining the soap, as the percentage of
+sodium sulfate increases in the salt. When the salt contains 25 per
+cent. sodium sulfate it is advisable to throw it away. Sulfuric acid,
+however, is considerably cheaper than hydrochloric and this more than
+compensates the necessity of having to eventually reject the recovered
+salt. It may here also be mentioned that recovered salt contains 5-7 per
+cent. glycerine which should be washed out in the evaporator before it
+is thrown away. The following tables give the approximate theoretical
+amounts of acids of various strengths required to neutralize one pound
+of caustic soda:</p>
+
+<p>
+For 1 pound of caustic soda&mdash;</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>3.25</td><td align='left'>lbs.</td><td align='left'>18&deg; B.</td><td align='left'>hydrochloric</td><td align='left'>(muriatic)</td><td align='left'>acid</td><td align='left'>are</td><td align='left'>required.</td></tr>
+<tr><td align='left'>2.92</td><td align='left'>"</td><td align='left'>20&deg; B.</td><td align='center'>"</td><td align='center'>"</td><td align='center'>"</td><td align='center'>"</td><td align='center'>"</td></tr>
+<tr><td align='left'>2.58</td><td align='left'>"</td><td align='left'>22&deg; B.</td><td align='center'>"</td><td align='center'>"</td><td align='center'>"</td><td align='center'>"</td><td align='center'>"</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_112" id="Page_112">[Pg 112]</a></span></p>
+
+
+<p>
+For 1 pound of caustic soda&mdash;</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>1.93</td><td align='left'>lbs.</td><td align='left'>50&deg; B.</td><td align='left'>sulphuric</td><td align='left'>acid</td><td align='left'>are</td><td align='left'>required.</td></tr>
+<tr><td align='left'>1.54</td><td align='left'>"</td><td align='left'>60&deg; B.</td><td align='center'>"</td><td align='center'>"</td><td align='center'>"</td><td align='center'>"</td></tr>
+<tr><td align='left'>1.28</td><td align='left'>"</td><td align='left'>66&deg; B.</td><td align='center'>"</td><td align='center'>"</td><td align='center'>"</td><td align='center'>"</td></tr>
+</table></div>
+
+
+<p>It is, of course, feasible to neutralize the spent lye without first
+determining the causticity by titrating a sample and this is often the
+case. The operator under such conditions first adds the sulfate of
+alumina, then the acid, using litmus paper as his indicator.
+Comparatively, this method of treatment is much slower and not as
+positive, as the amount of acid or alkali to be added is at all times
+uncertain, for in the foaming of the lyes their action on litmus is
+misleading.</p>
+
+<p>After the lye has been filtered to the filtered lye tank it is fed to
+the evaporator, the method of operation of which varies somewhat with
+different styles or makes. When it first enters the evaporator the lye
+is about 11&deg;-12&deg; B. After boiling the density will gradually rise to 27&deg;
+B. and remain at this gravity for some time and during which time most
+of the salt is dropped out in the salt filter. As the lye concentrates
+the gravity gradually rises to 28&deg;-30&deg; B., which is half crude glycerine
+and contains about 60 per cent. glycerine. Some operators carry the
+evaporation to this point and accumulate a quantity of half crude before
+going on to crude. After half crude is obtained the temperature on the
+evaporator increases, the vacuum increases and the pressure on the
+condensation drain goes up (using the same amount of live steam). As the
+liquor grows heavier the amount of evaporation is less, and less steam
+is required necessitating the regulation of the steam pressure on the
+drum. When a temperature of 210&deg; F. on the evaporator, with 26 or more
+inches vacuum on the pump is arrived at, the crude stage has been
+reached and the liquor now contains about 80 per cent. glycerine in
+which shape it is<span class='pagenum'><a name="Page_113" id="Page_113">[Pg 113]</a></span> usually sold by soap manufacturers. A greater
+concentration requires more intricate apparatus. After settling a day in
+the crude tank it is drummed.</p>
+
+<p>Crude glycerine (about 80 per cent. glycerol) free from salt is 33&deg; B.,
+or has a specific gravity of 1.3. A sample boiled in an open dish boils
+at a temperature of 155&deg; C. or over.</p>
+
+
+<h3>TWITCHELL PROCESS.</h3>
+
+<p>The Twitchell process of saponification consists of causing an almost
+complete cleavage of fats and oils by the use of the Twitchell reagent
+or saponifier, a sulfo-aromatic compound. This is made by the action of
+concentrated sulfuric acid upon a solution of oleic acid or stearic acid
+in an aromatic hydrocarbon. From 0.5 per cent. to 3 per cent. of the
+reagent is added and saponification takes place from 12-48 hours by
+heating in a current of live steam. The reaction is usually accelerated
+by the presence of a few per cent. of free fatty acids as a starter.
+Recently the Twitchell double reagent has been introduced through which
+it is claimed that better colored fatty acids are obtained and the
+glycerine is free from ash.</p>
+
+<p>The advantages claimed for the Twitchell process as outlined by
+Joslin<a name="FNanchor_12_12" id="FNanchor_12_12"></a><a href="#Footnote_12_12" class="fnanchor">[12]</a> are as follows:</p>
+
+<p>1. All the glycerine is separated from the stock before entering the
+kettle, preventing loss of glycerine in the soap and removing glycerine
+from spent lye.</p>
+
+<p>2. The liquors contain 15-20 per cent. glycerine whereas spent lyes
+contain but 3-5 per cent. necessitating less evaporation and
+consequently being more economical in steam, labor and time.</p>
+
+<p>3. No salt is obtained in the liquors which makes the evaporation
+cheaper and removes the cause of corrosion of<span class='pagenum'><a name="Page_114" id="Page_114">[Pg 114]</a></span> the evaporator; also
+saves the glycerine retained by the salt.</p>
+
+<p>4. The glycerine liquors are purer and thus the treatment of the lyes is
+cheaper and simpler and the evaporation less difficult.</p>
+
+<p>5. The glycerine can readily be evaporated to 90 per cent. crude rather
+than 80 per cent. crude, thus saving drums, labor in handling and
+freight. The glycerine furthermore receives a higher rating and price,
+being known as saponification crude which develops no glycols in
+refining it.</p>
+
+<p>6. The fatty acids obtained by the Twitchell saponifier may be converted
+into soap by carbonates, thus saving cost in alkali.</p>
+
+<p>7. There is a decrease in the odor of many strong smelling stocks.</p>
+
+<p>8. The glycerine may be obtained from half boiled and cold made soaps as
+well as soft (potash) soaps.</p>
+
+<p>While the advantages thus outlined are of decided value in the
+employment of the Twitchell process, the one great disadvantage is that
+the fatty acids obtained are rather dark in color and are not
+satisfactorily employed for the making of a soap where whiteness of
+color is desired.</p>
+
+<p>To carry out the process the previously heated oil or fat to be
+saponified is run into a lead lined tank. As greases and tallow often
+contain impurities a preliminary treatment with sulfuric acid is
+necessary. For a grease 1.25 per cent. of half water and half 66&deg; B.
+sulfuric acid is the approximate amount. The undiluted 66&deg; B. acid
+should never be added directly, as the grease would be charred by this.
+The grease should be agitated by steam after the required percentage of
+acid, calculated on the weight of the grease, has been added. The wash
+lye coming off should be 7&deg;-10&deg; B. on a good clean grease or 15&deg;-22&deg; B.
+on cotton oil or a poor grease. As has been<span class='pagenum'><a name="Page_115" id="Page_115">[Pg 115]</a></span> stated the grease is heated
+before the acid is added or the condensation of the steam necessitates
+the addition of more acid. After having boiled for 1-2 hours the grease
+is allowed to settle for 12 hours and run off through a swivel pipe.</p>
+
+<p>After the grease has been washed, as just explained, and settled, it is
+pumped into a covered wooden tank containing an open brass coil. Some of
+the second lye from a previous run is usually left in this tank and the
+grease pumped into this. The amount of this lye should be about
+one-third to one-half the weight of the grease so that there is about 60
+per cent. by weight of grease in the tank after 24 hours boiling. Where
+occasions arise when there is no second lye about 50 per cent. by weight
+of distilled water to the amount of grease is run into the tank to
+replace the lye. The saponifier is then added through a glass or granite
+ware funnel after the contents of the tank have been brought to a boil.
+If the boiling is to be continued 48 hours, 1 per cent. of saponifier is
+added. For 24 hours boiling add 1.5 per cent. The boiling is continued
+for 24-48 hours allowing 18 inches for boiling room or the grease will
+boil over.</p>
+
+<p>After boiling has continued the required length of time the mass is
+settled and the glycerine water is drawn off to the treatment tank.
+Should a permanent emulsion have formed, due to adding too great an
+amount of saponifier, a little sulfuric acid (0.1 per cent.-0.3 per
+cent.) will readily break this. During the time this is being done the
+space between the grease and the cover on the tank is kept filled with
+steam as contact with the air darkens the fatty acids.</p>
+
+<p>To the grease remaining in the tank distilled water (condensed water
+from steam coils) to one-half its volume is added and the boiling
+continued 12-24 hours. The grease<span class='pagenum'><a name="Page_116" id="Page_116">[Pg 116]</a></span> is then settled and the clear grease
+run off through a swivel pipe. A layer of emulsion usually forms between
+the clear grease and lye so that it may easily be determined when the
+grease has all been run off. To prevent discoloration of the fatty acids
+it is necessary to neutralize the lye with barium carbonate. The amount
+of this to be added depends upon the percentage of saponifier used.
+About 1/10 the weight of saponifier is the right amount. The barium
+carbonate is added through the funnel at the top of the tank mixed with
+a little water and the lye tested until it is neutral to methyl orange
+indicator. When the fatty acids are thus treated they will not darken
+upon exposure to the air when run off.</p>
+
+<p>Fresh grease is now pumped into the lye or water remaining in the tank
+and the process repeated.</p>
+
+<p>The glycerine water or first lye is run to the treatment tank, the fat
+skimmed off and neutralized with lime until it shows pink with
+phenolphthalein, after having been thoroughly boiled with steam. About
+0.25 per cent. lime is the proper amount to add. The mixture is then
+allowed to settle and the supernatant mixture drawn off and run to the
+glycerine evaporator feed tank. The lime which holds considerable
+glycerine is filtered and the liquor added to the other. The evaporation
+is carried out in two stages. The glycerine water is first evaporated to
+about 60 per cent. glycerol, then dropped into a settling tank to settle
+out the calcium sulfate. The clear liquor is then evaporated to crude
+(about 90 per cent. glycerine) and the sediment filtered and also
+evaporated to crude.</p>
+
+<p>As to the amount of saponifier to use on various stocks, this is best
+determined by experiment as to how high a percentage gives dark colored
+fatty acids. For good stock such as clean tallow, prime cottonseed oil,
+corn oil, cocoanut oil and stock of this kind 0.75 per cent. saponifier<span class='pagenum'><a name="Page_117" id="Page_117">[Pg 117]</a></span>
+is sufficient. For poorer grades of tallow, house grease, poor
+cottonseed oil, etc., 1 per cent. saponifier is required and for poorer
+grade greases higher percentages. The percentage of fatty acids
+developed varies in various stocks, and also varies with the care that
+the operation is carried out, but is usually between 85 per cent.-95 per
+cent. Due to the water taken up in the saponification process there is a
+yield of about 103 pounds of fatty acids and glycerine for 100 pounds of
+fat.</p>
+
+<p>The Twitchell reagent has undoubtedly caused a decided advance in the
+saponification of fats and oils and has been of great value to the soap
+manufacturer, because with a small expenditure it is possible to compete
+with the much more expensive equipment necessary for autoclave
+saponification. The drawback, however, has been that the reagent
+imparted a dark color to the fatty acids obtained, due to decomposition
+products forming when the reagent is made, and hence is not suitable for
+use in soaps where whiteness of color is desired.</p>
+
+<p>There have recently been two new reagents introduced which act as
+catalyzers in splitting fats, just as the Twitchell reagent acts, but
+the fatty acids produced by the cleavage are of good color. The
+saponification, furthermore, takes place more rapidly. These are the
+Pfeilring reagent and Kontact reagent.</p>
+
+<p>The Pfeilring reagent is very similar to the Twitchell reagent, being
+made from hydrogenated castor oil and naphthalene by sulfonation with
+concentrated sulfuric acid. It is manufactured in Germany and is being
+extensively used in that country with good success.</p>
+
+<p>The Kontact or Petroff reagent, discovered by Petroff in Russia, is made
+from sulfonated mineral oils. Until very recently it has only been
+manufactured in Europe, but now that it has been found possible to
+obtain the proper mineral<span class='pagenum'><a name="Page_118" id="Page_118">[Pg 118]</a></span> constituent from American petroleum, it is
+being manufactured in this country, and it is very probable that it will
+replace the Twitchell reagent because of the advantages derived by using
+it, as compared to the old Twitchell reagent.</p>
+
+<p>The method and equipment necessary for employing either the Pfeilring or
+Kontact reagents is exactly the same as in using the Twitchell process.</p>
+
+
+<h3>AUTOCLAVE SAPONIFICATION.</h3>
+
+<p>While the introduction of the Twitchell process to a great extent
+replaced the autoclave method of saponification for obtaining fatty
+acids for soap making, the autoclave method is also used. This process
+consists in heating the previously purified fat or oil in the presence
+of lime and water, or water only, for several hours, which causes a
+splitting of the glycerides into fatty acids and glycerine. The
+advantage of autoclave saponification over the Twitchell process is that
+a greater cleavage of the fats and oils results in less time and at a
+slightly less expense. The glycerine thus obtained is also purer and of
+better color than that obtained by Twitchelling the fats.</p>
+
+<p>An autoclave or digestor consists of a strongly constructed, closed
+cylindrical tank, usually made of copper, and is so built as to resist
+internal pressure. The digestor is usually 3 to 5 feet in diameter and
+from 18 to 25 feet high. It may be set up horizontally or vertically and
+is covered with an asbestos jacket to retain the heat. Various inlets
+and outlets for the fats, steam, etc., as well as a pressure gauge and
+safety valve are also a necessary part of the equipment.</p>
+
+
+<h3>LIME SAPONIFICATION.</h3>
+
+<p>The saponification in an autoclave is usually carried out by introducing
+the fats into the autoclave with a percentage<span class='pagenum'><a name="Page_119" id="Page_119">[Pg 119]</a></span> of lime, magnesia or zinc
+oxide, together with water. If the fats contain any great amount of
+impurities, it is first necessary to purify them either by a treatment
+with weak sulfuric acid, as described under the Twitchell process, or by
+boiling them up with brine and settling out the impurities from the hot
+fat.</p>
+
+<p>To charge the autoclave a partial vacuum is created therein by
+condensation of steam just before running the purified oil in from an
+elevated tank. The required quantity of unslaked lime, 2 to 4 per cent.
+of the weight of the fat, is run in with the molten fat, together with
+30 per cent. to 50 per cent. of water. While 8.7 per cent. lime is
+theoretically required, practice has shown that 2 per cent. to 4 per
+cent. is sufficient. The digestor, having been charged and adjusted,
+steam is turned on and a pressure of 8 to 10 atmospheres maintained
+thereon for a period of six to ten hours. Samples of the fat are taken
+at various intervals and the percentage of free fatty acids determined.
+When the saponification is completed the contents of the autoclave are
+removed, usually by blowing out the digestor into a wooden settling
+tank, or by first running off the glycerine water and then blowing out
+the lime, soap and fatty acids. The mass discharged from the digestor
+separates into two layers, the upper consisting of a mixture of lime
+soap or "rock" and fatty acids, and the lower layer contains the
+glycerine or "sweet" water. The glycerine water is first run off through
+a clearing tank or oil separator, if this has not been done directly
+from the autoclave, and the mass remaining washed once or twice more
+with water to remove any glycerine still retained by the lime soap. The
+calculated amount of sulfuric acid to decompose the lime "rock" is then
+added, and the mass agitated until the fatty acids contained therein are
+entirely set free. Another small wash is then given and the wash<span class='pagenum'><a name="Page_120" id="Page_120">[Pg 120]</a></span> water
+added to the glycerine water already run off. The glycerine water is
+neutralized with lime, filtered and concentrated as in the Twitchell
+process.</p>
+
+<p>Due to the difficulties of working the autoclave saponification with
+lime, decomposing the large amount of lime soap obtained and dealing
+with much gypsum formed thereby which collects as a sediment and
+necessitates cleaning the tanks, other substances are used to replace
+lime. Magnesia, about 2 per cent. of the weight of the fat, is used and
+gives better results than lime. One-half to 1 per cent. of zinc oxide of
+the weight of the fat is even better adapted and is now being
+extensively employed for this purpose. In using zinc oxide it is
+possible to recover the zinc salts and use them over again in the
+digestor, which makes the process as cheap to work as with lime, with
+far more satisfactory results.</p>
+
+
+<h3>ACID SAPONIFICATION.</h3>
+
+<p>While it is possible to saponify fats and oils in an autoclave with the
+addition of acid to the fat, unless a specially-constructed digestor is
+built, the action of the acid on the metal from which the autoclave is
+constructed prohibits its use. The acid saponification is therefore
+carried out by another method.</p>
+
+<p>The method of procedure for acid saponification, therefore, is to first
+purify the fats with dilute acid as already described. The purified, hot
+or warm, dry fat is then run to a specially-built acidifier or a
+lead-lined tank and from 4 per cent. to 6 per cent. of concentrated
+sulfuric acid added to the fat, depending upon its character, the degree
+of saponification required, temperature and time of saponification. A
+temperature of 110 degrees C. is maintained and the mass mixed from four
+to six hours. The tank is then allowed to settle out the tar formed
+during the saponification,<span class='pagenum'><a name="Page_121" id="Page_121">[Pg 121]</a></span> and the fatty acids run off to another tank
+and boiled up about three times with one-third the amount of water. The
+water thus obtained contains the glycerine, and after neutralization is
+concentrated.</p>
+
+
+<h3>AQUEOUS SAPONIFICATION.</h3>
+
+<p>While lime or a similar substance is ordinarily used to aid in splitting
+fats in an autoclave, the old water process is still used. This is a
+convenient, though slower and more dangerous method, of producing the
+hydrolysis of the glyceride, as well as the simplest in that fatty acids
+and glycerine in a water solution are obtained. The method consists in
+merely charging the autoclave with fats and adding about 30 per cent. to
+40 per cent. of their weight of water, depending on the amount of free
+fatty acid and subjecting the charge to a pressure of 150 to 300 pounds,
+until the splitting has taken place. This is a much higher pressure than
+when lime is used and therefore a very strong autoclave is required.
+Since fatty acids and pure glycerine water are obtained no subsequent
+treatment of the finished charge is necessary except separating the
+glycerine water and giving the fatty acids a wash with water to remove
+all the glycerine from them.</p>
+
+
+<h3>SPLITTING FATS WITH FERMENTS.</h3>
+
+<p>In discussing the causes of rancidity of oils and fats it was pointed
+out that the initial splitting of these is due to enzymes, organized
+ferments. In the seeds of the castor oil plant, especially in the
+protoplasm of the seed, the enzyme which has the property of causing
+hydrolysis of the glycerides is found. The ferment from the seeds of the
+castor oil plant is now extracted and used upon a commercial basis for
+splitting fats.</p>
+
+<p>The equipment necessary to carry out this method of<span class='pagenum'><a name="Page_122" id="Page_122">[Pg 122]</a></span> saponification is a
+round, iron, lead-lined tank with a conical bottom, preferably about
+twice as long as it is wide. Open and closed steam coils are also
+necessary in the tank.</p>
+
+<p>The oils are first heated and run into this tank. The right temperature
+to heat these to is about 1 degree to 2 degrees above their
+solidification point. For liquid oils 23 degrees C. is the proper heat
+as under 20 degrees C. the cleavage takes place slowly. Fats titering 44
+degrees C. or above must be brought down in titer by mixing with them
+oils of a lower titer as the ferment or enzyme is killed at about 45
+degrees C. and thus loses its power of splitting. It is also necessary
+to have the fat in the liquid state or the ferment does not act. The
+proper temperature must be maintained with dry steam.</p>
+
+<p>It is, of course, necessary to add water, which may be any kind desired,
+condensed, water from steam coils, well, city, etc. From 30 per cent. to
+40 per cent., on the average 35 per cent. of water is added, as the
+amount necessary is regulated so as to not dilute the glycerine water
+unnecessarily. To increase the hydrolysis a catalyzer, some neutral
+salt, usually manganese sulfate is added in the proportion of 0.15 per
+cent. appears to vary directly as the saponification number of the fat
+or oil. The approximate percentages of fermentive substance to be added
+to various oils and fats follow:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Cocoanut oil</td><td align='left'>8%</td></tr>
+<tr><td align='left'>Palm Kernel oil</td><td align='left'>8%</td></tr>
+<tr><td align='left'>Cottonseed oil</td><td align='left'>6-7%</td></tr>
+<tr><td align='left'>Linseed oil</td><td align='left'>4-5%</td></tr>
+<tr><td align='left'>Tallow oil</td><td align='left'>8-10%</td></tr>
+</table></div>
+
+
+<p>The oil, water, manganese sulfate and ferment having been placed in the
+tank in the order named, the mixture is agitated with air for about a
+quarter of an hour to form<span class='pagenum'><a name="Page_123" id="Page_123">[Pg 123]</a></span> an even emulsion, in which state the mass is
+kept by stirring occasionally with air while the saponification is
+taking place. A temperature is maintained a degree or two above the
+titer point of the fat with closed steam which may be aided by covering
+the tank for a period of 24 to 48 hours. The splitting takes place
+rapidly at first, then proceeds more slowly. In 24 hours 80 per cent. of
+the fats are split and in 48 hours 85 per cent. to 90 per cent.</p>
+
+<p>When the cleavage has reached the desired point the mass is heated to 80
+degrees-85 degrees C. with live or indirect steam while stirring with
+air. Then 0.1 per cent.-0.15 per cent of concentrated sulfuric acid
+diluted with water is added to break the emulsion. When the emulsion is
+broken the glycerine water is allowed to settle out and drawn off. The
+glycerine water contains 12 per cent. to 25 per cent. glycerine and
+contains manganese sulfate, sulfuric acid and albuminous matter. Through
+neutralization with lime at boiling temperature and filtration the
+impurities can almost all be removed after which the glycerine water may
+be fed to the evaporator. Should it be desired to overcome the trouble
+due to the gypsum formed in the glycerine, the lime treatment may be
+combined with a previous treatment of the glycerine water with barium
+hydrate to remove the sulfuric acid, then later oxalic acid to
+precipitate the lime.</p>
+
+<p>The fatty acids obtained by splitting with ferments are of very good
+color and adaptable for soap making.</p>
+
+
+<h3>KREBITZ PROCESS.</h3>
+
+<p>The Krebitz process which has been used to some extent in Europe is
+based upon the conversion of the fat or oil into lime soap which is
+transformed into the soda soap by the addition of sodium carbonate. To
+carry out the process a convenient batch of, say, 10,000 pounds of fat
+or oil, is run into a shallow kettle containing 1,200 to 1,400 pounds of
+lime<span class='pagenum'><a name="Page_124" id="Page_124">[Pg 124]</a></span> previously slaked with 3,700 to 4,500 pounds of water. The mass is
+slowly heated with live steam to almost boiling until an emulsion is
+obtained. The tank is then covered and allowed to stand about 12 hours.
+The lime soap thus formed is dropped from the tank into the hopper of a
+mill, finely ground and conveyed to a leeching tank. The glycerine is
+washed out and the glycerine water run to a tank for evaporation. The
+soap is then further washed and these washings are run to other tanks to
+be used over again to wash a fresh batch of soap. About 150,000 pounds
+of water will wash the soap made from 10,000 pounds of fat which makes
+between 15,000 and 16,000 pounds of soap. The first wash contains
+approximately 10 per cent. glycerine and under ordinary circumstances
+this only need be evaporated for glycerine recovery.</p>
+
+<p>After extracting the glycerine the soap is slowly introduced into a
+boiling solution of sodium carbonate or soda ash and boiled until the
+soda has replaced the lime. This is indicated by the disappearance of
+the small lumps of lime soap. Caustic soda is then added to saponify the
+fat not converted by the lime saponification. The soap is then salted
+out and allowed to settle out the calcium carbonate. This drops to the
+bottom of the kettle as a heavy sludge entangling about 10 per cent. of
+the soap. A portion of this soap may be recovered by agitating the
+sludge with heat and water, pumping the soap off the top and filtering
+the remaining sludge.</p>
+
+<p>While the soap thus obtained is very good, the percentage of glycerine
+recovered is greatly increased and the cost of alkali as carbonate is
+less. The disadvantages are many. Large quantities of lime are required;
+it is difficult to recover the soap from the lime sludge; the operations
+are numerous prior to the soap making proper and rather complicated
+apparatus is required.<span class='pagenum'><a name="Page_125" id="Page_125">[Pg 125]</a></span></p>
+
+
+<h3>DISTILLATION OF FATTY ACIDS.</h3>
+
+<p>The fatty acids obtained by various methods of saponification may be
+further improved by distillation.</p>
+
+<p>In order to carry out this distillation, two methods may be pursued,
+first, the continuous method, whereby the fatty acids are continually
+distilled for five to six days, and, second, the two phase method,
+whereby the distillation continues for 16 to 20 hours, after which the
+residue is drawn off, treated with acid, and its distillate added to a
+fresh charge of fatty acids. The latter method is by far the best, since
+the advantages derived by thus proceeding more than compensate the
+necessity of cleaning the still. Better colored fatty acids are
+obtained; less unsaponifiable matter is contained therein; there is no
+accumulation of impurities; the amount of neutral fat is lessened
+because the treatment of the tar with acid causes a cleavage of the
+neutral fat and the candle tar or pitch obtained is harder and better
+and thus more valuable.</p>
+
+<p>The stills are usually built of copper, which are heated by both direct
+fire and superheated steam. Distillation under vacuum is advisable. To
+begin the distilling operation, the still is first filled with dry hot
+fatty acids to the proper level. Superheated steam is then admitted and
+the condenser is first heated to prevent the freezing of the fatty
+acids, passing over into same. When the temperature reaches 230 deg. C.
+the distillation begins. At the beginning, the fatty acids flow from the
+condenser, an intense green color, due to the formation of copper soaps
+produced by the action of the fatty acids on the copper still. This
+color may easily be removed by treating with dilute acid to decompose
+the copper soaps.</p>
+
+<p>In vacuum distillation, the operation is begun without<span class='pagenum'><a name="Page_126" id="Page_126">[Pg 126]</a></span> the use of
+vacuum. Vacuum is introduced only when the distillation has proceeded
+for a time and the introduction of this must be carefully regulated,
+else the rapid influence of vacuum will cause the contents of the still
+to overflow. When distillation has begun a constant level of fatty acids
+is retained therein by opening the feeding valve to same, and the heat
+is so regulated as to produce the desired rate of distillation. As soon
+as the distillate flows darker and slower, the feeding valve to the
+still is shut off and the distillation continued until most of the
+contents of the still are distilled off, which is indicated by a rise in
+the temperature. Distillation is then discontinued, the still shut down,
+and in about an hour the contents are sufficiently cool to be emptied.
+The residue is run off into a proper receiving vessel, treated with
+dilute acid and used in the distillation of tar.</p>
+
+<p>In the distillation of tar the same method as the above is followed,
+only distillation proceeds at a higher temperature. The first portion
+and last portion of the distillate from tar are so dark that it is
+necessary to add them to a fresh charge of fatty acids. By a well
+conducted distillation of tar about 50 per cent. of the fatty acids from
+the tar can be used to mix with the distilled fatty acids. The residue
+of this operation called stearine pitch or candle tar consists of a
+hard, brittle, dark substance. Elastic pitch only results where
+distillation has been kept constant for several days without
+interrupting the process, and re-distilling the tar. In a good
+distillation the distillation loss is 0.5 to 1.5% and loss in pitch
+1.5%. Fatty acids which are not acidified deliver about 3% of pitch.
+Very impure fats yield even a higher percentage in spite of acidifying.
+For a long time it was found impossible to find any use for stearine
+pitch, but in recent years a use has been found for same in the
+electrical installation of cables.</p>
+
+<div class="footnotes"><h3>FOOTNOTES:</h3>
+
+<div class="footnote"><p><a name="Footnote_12_12" id="Footnote_12_12"></a><a href="#FNanchor_12_12"><span class="label">[12]</span></a> Journ. Ind. Eng. Chem. (1909), I, p. 654.</p></div>
+</div>
+
+
+<hr style="width: 65%;" /><p><span class='pagenum'><a name="Page_127" id="Page_127">[Pg 127]</a></span></p>
+<h2>CHAPTER VI</h2>
+
+<h3>Analytical Methods.</h3>
+
+
+<p>While it is possible to attain a certain amount of efficiency in
+determining the worth of the raw material entering into the manufacture
+of soap through organoleptic methods, these are by no means accurate. It
+is, therefore, necessary to revert to chemical methods to correctly
+determine the selection of fats, oil or other substances used in soap
+making, as well as standardizing a particular soap manufactured and to
+properly regulate the glycerine recovered.</p>
+
+<p>It is not our purpose to cover in detail the numerous analytical
+processes which may be employed in the examination of fats and oils,
+alkalis, soap and glycerine, as these are fully and accurately covered
+in various texts, but rather to give briefly the necessary tests which
+ought to be carried out in factories where large amounts of soap are
+made. Occasion often arises where it is impossible to employ a chemist,
+yet it is possible to have this work done by a competent person or to
+have someone instruct himself as just how to carry out the more simple
+analyses, which is not a very difficult matter. The various standard
+solutions necessary to carrying out the simpler titrations can readily
+be purchased from dealers in chemical apparatus and it does not take
+extraordinary intelligence for anyone to operate a burette, yet in many
+soap plants in this country absolutely no attention is paid to the
+examining of raw material, though many thousand pounds are handled
+annually, which, if they were more carefully examined would result in
+the saving of much more money than<span class='pagenum'><a name="Page_128" id="Page_128">[Pg 128]</a></span> it costs to examine them or have
+them at least occasionally analyzed.</p>
+
+
+<h3>ANALYSIS OF FATS AND OILS.</h3>
+
+<p>In order to arrive at proper results in the analysis of a fat or oil, it
+is necessary to have a proper sample. To obtain this a sample of several
+of the packages of oil or fat is taken and these mixed or molten
+together into a composite sample which is used in making the tests. If
+the oil or fat is solid, a tester is used in taking the sample from the
+package and if they are liquid, it is a simple matter to draw off a
+uniform sample from each package and from these to form a composite
+sample.</p>
+
+<p>In purchasing an oil or fat for soap making, the manufacturer is usually
+interested in the amount of free fatty acid contained therein, of
+moisture, the titer, the percentage of unsaponifiable matter and to
+previously determine the color of soap which will be obtained where
+color is an object.</p>
+
+
+<h3>DETERMINATION OF FREE FATTY ACIDS.</h3>
+
+<p>Since the free fatty acid content of a fat or oil represents a loss of
+glycerine, the greater the percentage of free fatty acid, the less
+glycerine is contained in the fat or oil, it is advisable to purchase a
+fat or oil with the lower free acid, other properties and the price
+being the same.</p>
+
+<p>While the mean molecular weight of the mixed free fatty acids varies
+with the same and different oils or fats and should be determined for
+any particular analysis for accuracy, the free fatty acid is usually
+expressed as oleic acid, which has a molecular weight of 282.</p>
+
+<p>To carry out the analysis 5 to 20 grams of the fat are<span class='pagenum'><a name="Page_129" id="Page_129">[Pg 129]</a></span> weighed out into
+an Erlenmeyer flask and 50 cubic centimeters of carefully neutralized
+alcohol are added. In order to neutralize the alcohol add a few drops of
+phenolphthalein solution to same and add a weak caustic soda solution
+drop by drop until a very faint pink color is obtained upon shaking or
+stirring the alcohol thoroughly. The mixture of fat and neutralized
+alcohol is then heated to boiling and titrated with tenth normal alkali
+solution, using phenolphthalein as an indicator. As only the free fatty
+acids are readily soluble in the alcohol and the fat itself only
+slightly mixes with it, the flask should be well agitated toward the end
+of the titration. When a faint pink color remains after thoroughly
+agitating the flask the end point is reached. In order to calculate the
+percentage of free fatty acid as oleic acid, multiply the number of
+cubic centimeters of tenth normal alkali used as read on the burette by
+0.0282 and divide by the number of grams of fat taken for the
+determination and multiply by 100.</p>
+
+<p>When dark colored oils or fats are being titrated it is often difficult
+to obtain a good end point with phenolphthalein. In such cases about 2
+cubic centimeters of a 2 per cent. alcoholic solution of Alkali Blue 6 B
+is recommended.</p>
+
+<p>Another method of directly determining the free fatty acid content of
+tallow or grease upon which this determination is most often made is to
+weigh out into an Erlenmeyer flask exactly 5.645 grams of a sample of
+tallow or grease. Add about 75 cubic centimeters of neutralized alcohol.
+Heat until it boils, then titrate with tenth normal alkali and divide
+the reading by 2, which gives the percentage of free fatty acid as
+oleic. If a fifth normal caustic solution is used, the reading on the
+burette gives the percentage of free fatty acid directly.<span class='pagenum'><a name="Page_130" id="Page_130">[Pg 130]</a></span> This method,
+while it eliminates the necessity of calculation, is troublesome in that
+it is difficult to obtain the exact weight of fat.</p>
+
+
+<h3>MOISTURE.</h3>
+
+<p>To calculate the amount of moisture contained in a fat or oil 5 to 10
+grams are weighed into a flat bottom dish, together with a known amount
+of clean, dry sand, if it is so desired. The dish is then heated over a
+water bath, or at a temperature of 100-110 degs. C., until it no longer
+loses weight upon drying and reweighing the dish. One hour should elapse
+between the time the dish is put on the water bath and the time it is
+taken off to reweigh. The difference between the weight of the dish is
+put on the water bath and the time it is taken off when it reaches a
+constant weight is moisture. This difference divided by the original
+weight of the fat or oil &times; 100 gives the percentage of moisture.</p>
+
+<p>When highly unsaturated fats or oils are being analyzed for moisture, an
+error may be introduced either by the absorption of oxygen, which is
+accelerated at higher temperature, or by the formation of volatile fatty
+acids. The former causes an increase in weight, the latter causes a
+decrease. To obviate this, the above operation of drying should be
+carried out in the presence of some inert gas like hydrogen, carbon
+dioxide, or nitrogen.</p>
+
+<h3>
+TITER.</h3>
+
+<p>The titer of a fat or oil is really an indication of the amount of
+stearic acid contained therein. The titer, expressed in degrees
+Centigrade, is the solidification point of the fatty acids of an oil or
+fat. In order to carry out the operation a Centigrade thermometer
+graduated in one or two-tenths of a degree is necessary. A thermometer
+graduated<span class='pagenum'><a name="Page_131" id="Page_131">[Pg 131]</a></span> between 10 degs. centigrade to 60 degs. centigrade is best
+adapted and the graduations should be clear cut and distinct.</p>
+
+<p>To make the determination about 30 grams of fat are roughly weighed in a
+metal dish and 30-40 cubic centimeters of a 30 per cent. (36 degs.
+Baum&eacute;) solution of sodium hydroxide, together with 30-40 cubic
+centimeters of alcohol, denatured alcohol will do, are added and the
+mass heated until saponified. Heat over a low flame or over an asbestos
+plate until the soap thus formed is dry, constantly stirring the
+contents of the dish to prevent burning. The dried soap is then
+dissolved in about 1000 cubic centimeters of water, being certain that
+all the alcohol has been expelled by boiling the soap solution for about
+half an hour. When the soap is in solution add sufficient sulphuric acid
+to decompose the soap, approximately 100 cubic centimeters of 25 degs.
+Baum&eacute; sulphuric acid, and boil until the fatty acids form a clear layer
+on top of the liquid. A few pieces of pumice stone put into the mixture
+will prevent the bumping caused by boiling. Siphon off the water from
+the bottom of the dish and wash the fatty acids with boiling water until
+free from sulphuric acid. Collect the fatty acids in a small casserole
+or beaker and dry them over a steam bath or drying oven at 110 degs.
+Centigrade. When the fatty acids are dry, cool them to about 10 degs.
+above the titer expected and transfer them to a titer tube or short test
+tube which is firmly supported by a cork in the opening of a salt mouth
+bottle. Hang the thermometer by a cord from above the supported tube so
+it reaches close to the bottom when in the titer tube containing the
+fatty acids and so that it may be used as a stirrer. Stir the mass
+rather slowly, closely noting the temperature. The temperature will
+gradually<span class='pagenum'><a name="Page_132" id="Page_132">[Pg 132]</a></span> fall during the stirring operation and finally remain
+stationary for half a minute or so then rise from 0.1 to 0.5 degs. The
+highest point to which the mercury rises after having been stationary is
+taken as the reading of the titer.</p>
+
+
+<h3>DETERMINATION OF UNSAPONIFIABLE MATTER.</h3>
+
+<p>In order to determine the unsaponifiable matter in fats and oils they
+are first saponified, then the unsaponifiable, which consists mainly of
+hydrocarbons and the higher alcohols cholesterol or phytosterol, is
+extracted with ether or petroleum ether, the ether evaporated and the
+residue weighed as unsaponifiable.</p>
+
+<p>To carry out the process first saponify about 5 grams of fat or oil with
+an excess of alcoholic potassium hydrate, 20-30 cubic centimeters of a 1
+to 10 solution of potassium hydroxide in alcohol until the alcohol is
+evaporated over a steam bath. Wash the soap thus formed into a
+separatory funnel of 200 cubic centimeters capacity with 80-100 cubic
+centimeters water. Then add about 60 cubic centimeters of ether,
+petroleum ether or 86 degs. gasoline and thoroughly shake the funnel to
+extract the unsaponifiable. Should the two layers not separate readily,
+add a few cubic centimeters of alcohol, which will readily cause them to
+separate. Draw off the watery solution from beneath and wash the ether
+with water containing a few drops of sodium hydrate and run to another
+dish. Pour the watery solution into the funnel again and repeat the
+extraction once or twice more or until the ether shows no discoloration.
+Combine the ether extractions into the funnel and wash with water until
+no alkaline reaction is obtained from the wash water. Run the ether
+extract to a weighed dish, evaporate and dry rapidly in a drying<span class='pagenum'><a name="Page_133" id="Page_133">[Pg 133]</a></span> oven.
+As some of the hydrocarbons are readily volatile at 100 degs.
+Centigrade, the drying should not be carried on any longer than
+necessary. The residue is then weighed and the original weight of fat
+taken divided into the weight of the residue &times; 100 gives the percentage
+unsaponifiable.</p>
+
+
+<h3>TEST FOR COLOR OF SOAP.</h3>
+
+<p>It is often desirable to determine the color of the finished soap by a
+rapid determination before it is made into soap. It often happens,
+especially with the tallows, that a dark colored sample produces a light
+colored soap, whereas a bleached light colored tallow produces a soap
+off shade.</p>
+
+<p>To rapidly determine whether the color easily washes out of the tallow
+with lye, 100 cubic centimeters of tallow are saponified in an enameled
+or iron dish with 100 cubic centimeters of 21 degs. Baum&eacute; soda lye and
+100 cubic centimeters of denatured alcohol. Continue heating over a wire
+gauze until all the alcohol is expelled and then add 50 cubic
+centimeters of the 21 degs. Baum&eacute; lye to grain the soap. Allow the lyes
+to settle and with an inverted pipette draw off the lyes into a test
+tube or bottle. Close the soap with 100 cubic centimeters of hot water
+and when closed again grain with 50 cubic centimeters of the lye by just
+bringing to a boil over an open flame. Again allow the lyes to settle
+and put aside a sample of the lye for comparison. Repeat the process of
+closing, graining and settling and take a sample of lye. If the lye is
+still discolored repeat the above operations again or until the lye is
+colorless. Ordinarily all the color will come out with the third lye.
+The soap thus obtained contains considerable water which makes it appear
+white. The soap is, therefore, dried to about 15 per cent. moisture and
+examined<span class='pagenum'><a name="Page_134" id="Page_134">[Pg 134]</a></span> for color. The color thus obtained is a very good criterion as
+to what may be expected in the soap kettle.</p>
+
+<p>By making the above analyses of fats or oils the main properties as to
+their adaptability for being made into soap are determined. In some
+cases, especially where adulteration or mixtures of oils are suspected,
+it is necessary to further analyze same. The methods of carrying out
+these analyses are fully covered by various texts on fats and oils and
+we will not go into details regarding the method of procedure in
+carrying these out.</p>
+
+
+<h3>TESTING OF ALKALIS USED IN SOAP MAKING.</h3>
+
+<p>The alkalis entering into the manufacture of soap such as caustic soda
+or sodium hydroxide, caustic potash or potassium hydrate, carbonate of
+soda or sodium carbonate, carbonate of potash or potassium carbonate
+usually contain impurities which do not enter into combination with the
+fats or fatty acids to form soap. It is out of the question to use
+chemically pure alkalis in soap making, hence it is often necessary to
+determine the alkalinity of an alkali. It may again be pointed out that
+in saponifying a neutral fat or oil only caustic soda or potash are
+efficient and the carbonate contained in these only combines to a more
+or less extent with any free fatty acids contained in the oils or fats.
+Caustic soda or potash or lyes made from these alkalis upon exposure to
+the air are gradually converted into sodium or potassium carbonate by
+the action of the carbon dioxide contained in the air. While the amount
+of carbonate thus formed is not very great and is greatest upon the
+surface, all lyes as well as caustic alkalis contain some carbonate.
+This carbonate introduces an error in the analysis of caustic alkalis
+when accuracy is required and thus in the analysis of caustic soda or
+potash it is necessary to remove the carbonate<span class='pagenum'><a name="Page_135" id="Page_135">[Pg 135]</a></span> when the true alkalinity
+as sodium hydroxide or potassium hydroxide is desired. This may be done
+by titration in alcohol which has been neutralized.</p>
+
+<p>In order to determine the alkalinity of any of the above mentioned
+alkalis, it is first necessary to obtain a representative sample of the
+substance to be analyzed. To do this take small samples from various
+portions of the package and combine them into a composite sample.
+Caustic potash and soda are hygroscopic and samples should be weighed at
+once or kept in a well stoppered bottle. Sodium or potassium carbonate
+can be weighed more easily as they do not rapidly absorb moisture from
+the air.</p>
+
+<p>To weigh the caustic soda or potash place about five grams on a watch
+glass on a balance and weigh as rapidly as possible. Wash into a 500
+cubic centimeter volumetric flask and bring to the mark with distilled
+water. Pipette off 50 cubic centimeters into a 200 cubic centimeter
+beaker, dilute slightly with distilled water, add a few drops of methyl
+orange indicator and titrate with normal acid. For the carbonates about
+1 gram may be weighed, washed into a 400 cubic centimeter beaker,
+diluted with distilled water, methyl orange indicator added and titrated
+with normal acid. It is advisable to use methyl orange indicator in
+these titrations as phenolphthalein is affected by the carbon dioxide
+generated when an acid reacts with a carbonate and does not give the
+proper end point, unless the solution is boiled to expel the carbon
+dioxide. Litmus may also be used as the indicator, but here again it is
+necessary to boil as carbon dioxide also affects this substance. As an
+aid to the action of these common indicators the following table may be
+helpful:<span class='pagenum'><a name="Page_136" id="Page_136">[Pg 136]</a></span></p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'><i>Indicator.</i></td><td align='left'><i>Color in Acid Solution.</i></td><td align='left'><i>Color in Alkaline Solution.</i></td><td align='left'><i>Action of CO<sub>2</sub>.</i></td></tr>
+<tr><td align='left'>Methyl orange</td><td align='left'>Red</td><td align='left'>Yellow</td><td align='left'>Very slightly acid</td></tr>
+<tr><td align='left'>Phenolphthalein</td><td align='left'>Colorless</td><td align='left'>Red</td><td align='left'>Acid</td></tr>
+<tr><td align='left'>Litmus</td><td align='left'>Red</td><td align='left'>Blue</td><td align='left'>Acid</td></tr>
+</table></div>
+
+
+<p>It may be further stated that methyl orange at the neutral point is
+orange in color.</p>
+
+<p>To calculate the percentage of effective alkali from the above
+titrations, it must be first pointed out that in the case of caustic
+potash or soda aliquot portions are taken. This is done to reduce the
+error necessarily involved by weighing, as the absorption of water is
+decided. Thus we had, say, exactly 5 grams which weighed 5.05 grams by
+the time it was balanced. This was dissolved in 500 cubic centimeters of
+water and 50 cubic centimeters or one tenth of the amount of the
+solution was taken, or in each 50 cubic centimeters there were 0.505
+grams of the sample. We thus reduced the error of weighing by one tenth
+provided other conditions introduce no error. In the case of the
+carbonates the weight is taken directly.</p>
+
+<p>One cubic centimeter of a normal acid solution is the equivalent of:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'></td><td align='left'>Grams.</td></tr>
+<tr><td align='left'>Sodium Carbonate, Na<sub>2</sub>CO<sub>3</sub></td><td align='left'>0.05305</td></tr>
+<tr><td align='left'>Sodium Hydroxide, NaOH</td><td align='left'>0.04006</td></tr>
+<tr><td align='left'>Sodium Oxide, Na<sub>2</sub>O</td><td align='left'>0.02905</td></tr>
+<tr><td align='left'>Carbonate K<sub>2</sub>CO<sub>3</sub></td><td align='left'>0.06908</td></tr>
+<tr><td align='left'>Potassium Hydroxide, KOH</td><td align='left'>0.05616</td></tr>
+<tr><td align='left'>Potassium Oxide, K<sub>2</sub>O</td><td align='left'>0.04715</td></tr>
+</table></div>
+
+
+<p>Hence to arrive at the alkalinity we multiply the number of cubic
+centimeters, read on the burette, by the factor opposite the terms in
+which we desire to express the alkalinity, divide the weight in grams
+thus obtained by the original weight taken, and multiply the result by
+100,<span class='pagenum'><a name="Page_137" id="Page_137">[Pg 137]</a></span> which gives the percentage of alkali in the proper terms. For
+example, say, we took the 0.505 grams of caustic potash as explained
+above and required 8.7 cubic centimeter normal acid to neutralize the
+solution, then</p>
+
+<p>
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8.7 &times; .05616 = .4886 grams KOH in sample</p>
+
+<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.4886<br />
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;----- &times; 100 = 96.73% KOH in sample.<br />
+&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.505
+</p>
+
+<p>Caustic potash often contains some caustic soda, and while it is
+possible to express the results in terms of KOH, regardless of any
+trouble that may be caused by this mixture in soap making, an error is
+introduced in the results, not all the alkali being caustic potash. In
+such cases it is advisable to consult a book on analysis as the analysis
+is far more complicated than those given we will not consider it. The
+presence of carbonates, as already stated, also causes an error. To
+overcome this the alkali is titrated in absolute alcohol, filtering off
+the insoluble carbonate. The soluble portion is caustic hydrate and may
+be titrated as such. The carbonate remaining on the filter paper is
+dissolved in water and titrated as carbonate.</p>
+
+
+<h3>SOAP ANALYSIS.</h3>
+
+<p>To obtain a sample of a cake of soap for analysis is a rather difficult
+matter as the moisture content of the outer and inner layer varies
+considerably. To overcome this difficulty a borer or sampler may be run
+right through the cake of soap, or slices may be cut from various parts
+of the cake, or the cake may be cut and run through a meat chopper
+several times and mixed. A sufficient amount of a homogeneous sample
+obtained by any of these methods is preserved for the entire analysis by
+keeping the soap in a securely stoppered bottle.</p>
+
+<p>The more important determinations of soap are moisture, free alkali, or
+fatty acid, combined alkali and total<span class='pagenum'><a name="Page_138" id="Page_138">[Pg 138]</a></span> fatty matter. Besides these it is
+often necessary to determine insoluble matter, glycerine, unsaponifiable
+matter, rosin and sugar.</p>
+
+
+<h3>MOISTURE.</h3>
+
+<p>The analysis of soap for moisture, at its best, is most unsatisfactory,
+for by heating it is impossible to drive off all the water, and on the
+other hand volatile oils driven off by heat are a part of the loss
+represented as moisture.</p>
+
+<p>The usual method of determining moisture is to weigh 2 to 3 grams of
+finely shaved soap on a watch glass and heat in an oven at 105 degrees
+C. for 2 to 3 hours. The loss in weight is represented as water,
+although it is really impossible to drive off all the water in this way.</p>
+
+<p>To overcome the difficulties just mentioned either the Smith or Fahrion
+method may be used. Allen recommends Smith's method which is said to be
+truthful to within 0.25 per cent. Fahrion's method, according to the
+author, gives reliable results to within 0.5 per cent. Both are more
+rapid than the above manipulation. To carry out the method of Smith, 5
+to 10 grams of finely ground soap are heated over a sand bath with a
+small Bunsen flame beneath it, in a large porcelain crucible. The
+heating takes 20 to 30 minutes, or until no further evidence is present
+of water being driven off. This may be tested by the fogging of a cold
+piece of glass held over the crucible immediately upon removing the
+burner. When no fog appears the soap is considered dry. Any lumps of
+soap may be broken up by a small glass rod, weighed with the crucible,
+and with a roughened end to more easily separate the lumps. Should the
+soap burn, this can readily be detected by the odor, which, of course,
+renders the analysis useless. The loss in weight is moisture.<span class='pagenum'><a name="Page_139" id="Page_139">[Pg 139]</a></span></p>
+
+<p>By Fahrion's method<a name="FNanchor_13_13" id="FNanchor_13_13"></a><a href="#Footnote_13_13" class="fnanchor">[13]</a>, 2 to 4 grams of soap are weighed in a platinum
+crucible and about three times its weight of oleic acid, which has been
+heated at 120 degrees C. until all the water is driven off and preserved
+from moisture, is added and reweighed. The dish is then cautiously
+heated with a small flame until all the water is driven off and all the
+soap is dissolved. Care must be exercised not to heat too highly or the
+oleic acid will decompose. The moment the water is all driven off a
+clear solution is formed, provided no fillers are present in the soap.
+The dish is then cooled in a dessicator and reweighed. The loss in
+weight of acid plus soap is moisture and is calculated on the weight of
+soap taken. This determination takes about fifteen minutes.</p>
+
+
+<h3>FREE ALKALI OR ACID.</h3>
+
+<h4>(<i>a</i>) <i>Alcoholic Method.</i></h4>
+
+<p>Test a freshly cut surface of the soap with a few drops of an alcoholic
+phenolphthalein solution. If it does not turn red it may be assumed free
+fat is present; should a red color appear, free alkali is present. In
+any case dissolve 2 to 5 grams of soap in 100 cubic centimeters of
+neutralized alcohol and heat to boiling until in solution. Filter off
+the undissolved portion containing carbonate, etc., and wash with
+alcohol. Add phenolphthalein to the filtrate and titrate with N/10 acid
+and calculate the per cent. of free alkali as sodium or potassium
+hydroxide. Should the filtrate be acid instead of alkaline, titrate with
+N/10 alkali and calculate the percentage of free fatty acid as oleic
+acid.</p>
+
+<p>The insoluble portion remaining on the filter paper is washed with water
+until all the carbonate is dissolved. The washings are then titrated
+with N/10 sulfuric acid<span class='pagenum'><a name="Page_140" id="Page_140">[Pg 140]</a></span> and expressed as sodium or potassium carbonate.
+Should borates or silicates be present it is possible to express in
+terms of these. If borax is present the carbon dioxide is boiled off
+after neutralizing exactly to methyl orange; cool, add mannite and
+phenolphthalein and titrate the boric acid with standard alkali.</p>
+
+<h4>(<i>b</i>) <i>Bosshard and Huggenberg Method.</i><a name="FNanchor_14_14" id="FNanchor_14_14"></a><a href="#Footnote_14_14" class="fnanchor">[14]</a></h4>
+
+<p>In using the alcoholic method for the determination of the free alkali
+or fat in soap there is a possibility of both free fat and free alkali
+being present. Upon boiling in an alcoholic solution the fat will be
+saponified, thus introducing an error in the analysis. The method of
+Bosshard and Huggenberg overcomes this objection. Their method is
+briefly as follows:</p>
+
+<h4><i>Reagents.</i></h4>
+
+<p>1. N/10 hydrochloric acid to standardize N/10 alcoholic sodium
+hydroxide.</p>
+
+<p>2. Approximately N/10 alcoholic sodium hydroxide to fix and control the
+N/40 stearic acid.</p>
+
+<p>3. N/40 stearic acid. Preparation: About 7.1 grams of stearic acid are
+dissolved in one liter of absolute alcohol, the solution filtered, the
+strength determined by titration against N/10 NaOH and then protected in
+a well stoppered bottle, or better still connected directly to the
+burette.</p>
+
+<p>4. A 10 per cent. solution of barium chloride. Preparation: 100 grams of
+barium chloride are dissolved in one liter of distilled water and
+filtered. The neutrality of the solution should be proven as it must be
+neutral.</p>
+
+<p>5. &#945; naphtholphthalein indicator according to Sorenson.
+Preparation: 0.1 gram of &#945; naphtholphthalein is dissolved in
+150 cubic centimeters of alcohol and 100 cubic<span class='pagenum'><a name="Page_141" id="Page_141">[Pg 141]</a></span> centimeters of water.
+For every 10 cubic centimeters of liquid use at least 12 drops of
+indicator.</p>
+
+<p>6. Phenolphthalein solution 1 gram to 100 cubic centimeter 96 per cent.
+alcohol.</p>
+
+<p>7. Solvent, 50 per cent. alcohol neutralized.</p>
+
+
+<h4>MANIPULATION.</h4>
+
+<p>First&mdash;Determine the strength of the N/10 alcoholic sodium hydroxide in
+terms of N/10 hydrochloric acid and calculate the factor, e. g.:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>10 c.c. N/10 alcoholic NaOH</td><td align='left'>= 9.95 N/10 HCl}</td><td rowspan="2">9.96</td></tr>
+<tr><td align='left'>10 c.c. N/10 alcoholic NaOH</td><td align='left'>= 9.96 N/10 HCl}</td></tr>
+</table></div>
+
+<p class="center">The alcoholic N/10 NaOH has a factor of 0.996.</p>
+
+<p>Second&mdash;Control the N/40 stearic acid with the above alkali to obtain
+its factor, e. g.:</p>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>40 c.c. N/40 alcoholic stearic acid =</td><td align='left'>10.18 c.c. N/10 NaOH }</td><td rowspan="2">} 10.2</td></tr>
+<tr><td align='left'>40 c.c. N/40 alcoholic stearic acid =</td><td align='left'>10.22 c.c. N/10 NaOH }</td></tr>
+</table></div>
+
+
+<p class="center">10.2 &times; F N/10 NaOH (0.996) = Factor N/40 stearic acid
+</p>
+
+<p class="center">&#8756;Factor N/40 stearic acid = 1.016.</p>
+
+<p>Third&mdash;About 5 grams of soap are weighed and dissolved in 100 cubic
+centimeters of 50 per cent. neutralized alcohol in a 250 cubic
+centimeter Erlenmeyer flask over a water bath and connected with a
+reflux condensor. When completely dissolved, which takes but a few
+moments, it is cooled by allowing a stream of running water to run over
+the outside of the flask.</p>
+
+<p>Fourth&mdash;The soap is precipitated with 15 to 20 cubic centimeters of the
+10 per cent. barium chloride solution.</p>
+
+<p>Fifth&mdash;After the addition of 2 to 5 cubic centimeters of &#945;
+naphtholphthalein solution the solution is titrated with N/40 alcoholic
+stearic acid. &#945; naphtholphthalein is red with an excess of
+stearic acid. To mark the color changes<span class='pagenum'><a name="Page_142" id="Page_142">[Pg 142]</a></span> it is advisable to first run a
+few blanks until the eye has become accustomed to the change in the
+indicator in the same way. The change from green to red can then be
+carefully observed.</p>
+
+<p>Let us presume 5 grams of soap were taken for the analysis and 20 cubic
+centimeters of N/40 stearic acid were required for the titration then to
+calculate the amount of NaOH since the stearic factor is 1.016.</p>
+
+<p>20 &times; 1.016 = 20.32 N/40 stearic acid really required.</p>
+
+<p>1 cubic centimeter N/40 stearic acid = 0.02 per cent. NaOH for 5 grams
+soap.</p>
+
+<p>&#916; 20.32 cubic centimeters N/40 stearic acid = 0.02 &times; 20.32
+per cent. NaOH for 5 grams soap.</p>
+
+<p>Hence the soap contains 0.4064 per cent. NaOH.</p>
+
+<p>It is necessary, however, to make a correction by this method. When the
+free alkali amounts to over 0.1 per cent. the correction is + 0.01, and
+when the free alkali exceeds 0.4 per cent. the correction is + 0.04,
+hence in the above case we multiply 0.004064 by 0.04, add this amount to
+0.004064 and multiply by 100 to obtain the true percentage. Should the
+alkalinity have been near 0.1 per cent. we would have multiplied by 0.01
+and added this.</p>
+
+<p>If carbonate is also present in the soap, another 5 grams of soap is
+dissolved in 100 cubic centimeters of 50 per cent. alcohol and the
+solution titrated directly after cooling with N/40 stearic acid, using
+&#945; naphtholphthalein or phenolphthalein as an indicator,
+without the addition of barium chloride. From the difference of the two
+titrations the alkali present as carbonate is determined.</p>
+
+<p>If the decomposed soap solution is colorless with phenolphthalein, free
+fatty acids are present, which may be quickly determined with alcoholic
+N/10 sodium hydroxide.<span class='pagenum'><a name="Page_143" id="Page_143">[Pg 143]</a></span></p>
+
+
+<h3>INSOLUBLE MATTER.</h3>
+
+<p>The insoluble matter in soap may consist of organic or inorganic
+substances. Among the organic substances which are usually present in
+soap are oat meal, bran, sawdust, etc., while among the common inorganic
+or mineral compounds are pumice, silex, clay, talc, zinc oxide,
+infusorial earth, sand or other material used as fillers.</p>
+
+<p>To determine insoluble matter, 5 grams of soap are dissolved in 75 cubic
+centimeters of hot water. The solution is filtered through a weighed
+gooch crucible or filter paper. The residue remaining on the filter is
+washed with hot water until all the soap is removed, is then dried to
+constant weight at 105 degrees C. and weighed. From the difference in
+weight of the gooch or filter paper and the dried residue remaining
+thereon after filtering and drying, the total percentage of insoluble
+matter may easily be calculated. By igniting the residue and reweighing
+the amount of insoluble mineral matter can be readily determined.</p>
+
+
+<h3>STARCH AND GELATINE.</h3>
+
+<p>Should starch or gelatine be present in soap it is necessary to extract
+5 grams of the soap with 100 cubic centimeters of 95 per cent.
+neutralized alcohol in a Soxhlet extractor until the residue on the
+extraction thimble is in a powder form. If necessary the apparatus
+should be disconnected and any lumps crushed, as these may contain soap.
+The residue remaining on the thimble consists of all substances present
+in soap, insoluble in alcohol. This is dried and weighed so that any
+percentage of impurities not actually determined can be found by
+difference. Starch and gelatine are separated from carbonate, sulfate
+and borate by dissolving the latter out through a filter with cold
+water. The starch and gelatine thus remaining can be determined by<span class='pagenum'><a name="Page_144" id="Page_144">[Pg 144]</a></span>
+known methods, starch by the method of direct hydrolysis<a name="FNanchor_15_15" id="FNanchor_15_15"></a><a href="#Footnote_15_15" class="fnanchor">[15]</a> and
+gelatine by Kjeldahling and calculating the corresponding amount of
+gelatine from the percentage of nitrogen (17.9%) therein.<a name="FNanchor_16_16" id="FNanchor_16_16"></a><a href="#Footnote_16_16" class="fnanchor">[16]</a></p>
+
+
+<h3>TOTAL FATTY AND RESIN ACIDS.</h3>
+
+<p>To the filtrate from the insoluble matter add 40 cubic centimeters of
+half normal sulfuric acid, all the acid being added at once. Boil, stir
+thoroughly for some minutes and keep warm on a water bath until the
+fatty acids have collected as a clear layer on the surface. Cool by
+placing the beaker in ice and syphon off the acid water through a
+filter. Should the fatty acids not readily congeal a weighed amount of
+dried bleached bees-wax or stearic acid may be added to the hot mixture.
+This fuses with the hot mass and forms a firm cake of fatty acids upon
+cooling. Without removing the fatty acids from the beaker, add about 300
+cubic centimeters of hot water, cool, syphon off the water through the
+same filter used before and wash again. Repeat washing, cooling and
+syphoning processes until the wash water is no longer acid. When this
+stage is reached, dissolve any fatty acid which may have remained on the
+filter with hot 95 per cent. alcohol into the beaker containing the
+fatty acids. Evaporate the alcohol and dry the beaker to constant weight
+over a water bath. The fatty acids thus obtained represent the combined
+fatty acids, uncombined fat and hydrocarbons.</p>
+
+
+<h3>DETERMINATION OF ROSIN.</h3>
+
+<p>If resin acids are present, this may be determined by the
+Liebermann-Storch reaction. To carry out this test shake 2 cubic
+centimeters of the fatty acids with 5 cubic<span class='pagenum'><a name="Page_145" id="Page_145">[Pg 145]</a></span> centimeters of acetic
+anhydride; warm slightly; cool; draw off the anhydride and add 1:1
+sulfuric acid. A violet color, which is not permanent, indicates the
+presence of rosin in the soap. The cholesterol in linseed or fish oil,
+which of course may be present in the soap, also give this reaction.</p>
+
+<p>Should resin acids be present, these may be separated by the Twitchell
+method, which depends upon the difference in the behavior of the fatty
+and resin acids when converted into their ethyl esters through the
+action of hydrochloric acid. This may be carried out as follows:</p>
+
+<p>Three grams of the dried mixed acids are dissolved in 25 cubic
+centimeters of absolute alcohol in a 100 cubic centimeter stoppered
+flask; the flask placed in cold water and shaken. To this cooled
+solution 25 cubic centimeters of absolute alcohol saturated with dry
+hydrochloric acid is added. The flask is shaken occasionally and the
+action allowed to continue for twenty minutes, then 10 grams of dry
+granular zinc chloride are added, the flask shaken and again allowed to
+stand for twenty minutes. The contents of the flask are then poured into
+200 cubic centimeters of water in a 500 cubic centimeter beaker and the
+flask rinsed out with alcohol. A small strip of zinc is placed in the
+beaker and the alcohol evaporated. The beaker is then cooled and
+transferred to a separatory funnel, washing out the beaker with 50 cubic
+centimeters of gasoline (boiling below 80 degrees C.) and extracting by
+shaking the funnel well. Draw off the acid solution after allowing to
+separate and wash the gasoline with water until free from hydrochloric
+acid. Draw off the gasoline solution and evaporate the gasoline.
+Dissolve the residue in neutral alcohol and titrate with standard alkali
+using phenolphthalein as an indicator. One cubic centimeter of normal
+alkali equals 0.346 grams of rosin. The rosin may<span class='pagenum'><a name="Page_146" id="Page_146">[Pg 146]</a></span> be gravimetrically
+determined by washing the gasoline extract with water, it not being
+necessary to wash absolutely free from acid, then adding 0.5 gram of
+potassium hydroxide and 5 cubic centimeters of alcohol in 50 cubic
+centimeters of water. Upon shaking the resin acids are rapidly
+saponified and extracted by the dilute alkaline solution as rosin soaps,
+while the ethyl esters remain in solution in the gasoline. Draw off the
+soap solution, wash the gasoline solution again with dilute alkali and
+unite the alkaline solutions. Decompose the alkaline soap solution with
+an excess of hydrochloric acid and weigh the resin acids liberated as in
+the determination of total fatty acids.</p>
+
+<p>According to Lewkowitsch, the results obtained by the volumetric method
+which assumes a combining weight of 346 for resin acids, are very likely
+to be high. On the other hand those obtained by the gravimetric method
+are too low.</p>
+
+<p>Leiste and Stiepel<a name="FNanchor_17_17" id="FNanchor_17_17"></a><a href="#Footnote_17_17" class="fnanchor">[17]</a> have devised a simpler method for the
+determination of rosin. They make use of the fact that the resin acids
+as sodium soaps are soluble in acetone and particularly acetone
+containing two per cent. water, while the fatty acid soaps are soluble
+in this solvent to the extent of only about 2 per cent. First of all it
+is necessary to show that the sample to be analyzed contains a mixture
+of resin and fatty acids. This may be done by the Liebermann-Storch
+reaction already described. Glycerine interferes with the method. Two
+grams of fatty acids or 3 grams of soap are weighed in a nickel crucible
+and dissolved in 15-20 cubic centimeters of alcohol. The solution is
+then neutralized with alcoholic sodium hydroxide, using phenolphthalein
+as an indicator. The mass is concentrated by heat over an asbestos plate
+until a slight film<span class='pagenum'><a name="Page_147" id="Page_147">[Pg 147]</a></span> forms over it. Then about 10 grams of sharp,
+granular, ignited sand are stirred in by means of a spatula, the alcohol
+further evaporated, the mixture being constantly stirred and then
+thoroughly dried in a drying oven. The solvent for the cooled mass is
+acetone containing 2 per cent. water. It is obtained from acetone dried
+by ignited sodium sulfate and adding 2 per cent. water by volume. One
+hundred cubic centimeters of this solvent are sufficient for extracting
+the above. The extraction of the rosin soap is conducted by adding 10
+cubic centimeters of acetone eight times, rubbing the mass thoroughly
+with a spatula and decanting. The decanted portions are combined in a
+beaker and the suspended fatty soaps allowed to separate. The mixture is
+then filtered into a previously weighed flask and washed several times
+with the acetone remaining. The solution of rosin soap should show no
+separation of solid matter after having evaporated to half the volume
+and allowing to cool. If a separation should occur another filtration
+and the slightest possible washing is necessary. To complete the
+analysis, the acetone is completely evaporated and the mass dried to
+constant weight in a drying oven. The weight found gives the weight of
+the rosin soap. In conducting the determination, it is important to dry
+the mixture of soap and sand thoroughly. In dealing with potash soaps it
+is necessary to separate the fatty acids from these and use them as
+acetone dissolves too great a quantity of a potash soap.</p>
+
+
+<h3>TOTAL ALKALI.</h3>
+
+<p>In the filtrate remaining after having washed the fatty acids in the
+determination of total fatty and resin acids all the alkali present as
+soap, as carbonate and as hydroxide remains in solution as sulfate. Upon
+titrating this solution with half normal alkali the difference between
+the<span class='pagenum'><a name="Page_148" id="Page_148">[Pg 148]</a></span> half normal acid used in decomposing the soap and alkali used in
+titrating the excess of acid gives the amount of total alkali in the
+soap. By deducting the amount of free alkali present as carbonate or
+hydroxide previously found the amount of combined alkali in the soap may
+be calculated.</p>
+
+<p>To quickly determine total alkali in soap a weighed portion of the soap
+may be ignited to a white ash and the ash titrated for alkalinity using
+methyl orange as an indicator.</p>
+
+
+<h3>UNSAPONIFIED MATTER.</h3>
+
+<p>Dissolve 5 grams of soap in 50 cubic centimeters of 50 per cent.
+alcohol. Should any free fatty acids be present neutralize them with
+standard alkali. Wash into a separatory funnel with 50 per cent. alcohol
+and extract with 100 cubic centimeters of gasoline, boiling at 50
+degrees to 60 degrees C. Wash the gasoline with water, draw off the
+watery layer. Run the gasoline into a weighed dish, evaporate the
+alcohol, dry and weigh the residue as unsaponified matter. The residue
+contains any hydrocarbon oils or fats not converted into soap.</p>
+
+
+<h3>SILICA AND SILICATES.</h3>
+
+<p>The insoluble silicates, sand, etc., are present in the ignited residue
+in the determination of insoluble matter. Sodium silicate, extensively
+used as a filler, however, will only show itself in forming a pasty
+liquid. Where it is desired to determine sodium silicate, 10 grams of
+soap are ashed by ignition, hydrochloric acid added to the ash in excess
+and evaporated to dryness. More hydrochloric acid is then added and the
+mass is again evaporated until dry; then cooled; moistened with
+hydrochloric acid; dissolved in water; filtered; washed; the filtrate
+evaporated to dryness and again taken up with hydrochloric acid and
+water;<span class='pagenum'><a name="Page_149" id="Page_149">[Pg 149]</a></span> filtered and washed. The precipitates are then combined and
+ignited. Silicon dioxide (SiO<sub>2</sub>) is thus formed, which can be
+calculated to sodium silicate (Na<sub>2</sub>Si<sub>4</sub>O<sub>9</sub>). Should other metals
+than alkali metals be suspected present the filtrate from the silica
+determinations should be examined.</p>
+
+
+<h3>GLYCERINE IN SOAP.</h3>
+
+<p>To determine the amount of glycerine contained in soap dissolve 25 grams
+in hot water, add a slight excess of sulfuric acid and keep hot until
+the fatty acids form as a clear layer on top. Cool the mass and remove
+the fatty acids. Filter the acid solution into a 25 cubic centimeter
+graduated flask; bring to the mark with water and determine the
+glycerine by the bichromate method as described under glycerine
+analysis.</p>
+
+<p>When sugar is present the bichromate would be reduced by the sugar,
+hence this method is not applicable. In this case remove the fatty acids
+as before, neutralize an aliquot portion with milk of lime, evaporate to
+10 cubic centimeters, add 2 grams of sand and milk of lime containing
+about 2 grams of calcium hydroxide and evaporate almost to dryness.
+Treat the moist residue with 5 cubic centimeters of 96 per cent.
+alcohol, rub the whole mass into a paste, then constantly stirring, heat
+on a water bath and decant into a 250 cubic centimeter graduated flask.
+Repeat the washing with 5 cubic centimeters of alcohol five or six
+times, each time pouring the washings into the flask; cool the flask to
+room temperature and fill to the mark with 96 per cent. alcohol, agitate
+the flask until well mixed and filter through a dry filter paper. Take
+200 cubic centimeters of the nitrate and evaporate to a syrupy
+consistency over a safety water bath. Wash the liquor into a stoppered
+flask with 20 cubic centimeters of absolute alcohol, add 30 cubic
+centimeters of absolute ether 10<span class='pagenum'><a name="Page_150" id="Page_150">[Pg 150]</a></span> cubic centimeters at a time, shaking
+well after each addition and let stand until clear. Pour off the
+solution through a filter into a weighed dish and wash out the flask
+with a mixture of three parts absolute ether and two parts absolute
+alcohol. Evaporate to a syrup, dry for one hour at the temperature of
+boiling water, weigh, ignite and weigh again. The loss is glycerine.
+This multiplied by 5/4 gives the total loss for the aliquot portion
+taken. The glycerine may also be determined by the acetin or bichromate
+methods after driving off the alcohol and ether if so desired.</p>
+
+
+<h3>SUGAR IN SOAP.</h3>
+
+<p>To determine sugar in soap, usually present in transparent soaps,
+decompose a soap solution of 5 grams of soap dissolved in 100 cubic
+centimeters of hot water with an excess of hydrochloric acid and
+separate the fatty acids as usual. Filter the acid solution into a
+graduated flask and make up to the mark. Take an aliquot containing
+approximately 1 per cent. of reducing sugar and determine the amount of
+sugar by the Soxhlet method.<a name="FNanchor_18_18" id="FNanchor_18_18"></a><a href="#Footnote_18_18" class="fnanchor">[18]</a></p>
+
+
+<h3>GLYCERINE ANALYSIS.</h3>
+
+<p>The methods of analyzing glycerine varied so greatly due to the fact
+that glycerine contained impurities which acted so much like glycerine
+as to introduce serious errors in the determinations of crude glycerine.
+This led to the appointment of committees in the United States and
+Europe to investigate the methods of glycerine analysis. An
+international committee met after their investigations and decided the
+acetin method should control the buying and selling of glycerine, but
+the more convenient bichromate method in a standardized form might be
+used<span class='pagenum'><a name="Page_151" id="Page_151">[Pg 151]</a></span> in factory control and other technical purposes. The following are
+the methods of analysis and sampling as suggested by the international
+committee:</p>
+
+
+<h3>SAMPLING.</h3>
+
+<p>The most satisfactory method available for sampling crude glycerine
+liable to contain suspended matter, or which is liable to deposit salt
+on settling, is to have the glycerine sampled by a mutually approved
+sampler as soon as possible after it is filled into drums, but in any
+case before any separation of salt has taken place. In such cases he
+shall sample with a sectional sampler (see appendix) then seal the
+drums, brand them with a number for identification, and keep a record of
+the brand number. The presence of any visible salt or other suspended
+matter is to be noted by the sampler, and a report of the same made in
+his certificate, together with the temperature of the glycerine. Each
+drum must be sampled. Glycerine which has deposited salt or other solid
+matter cannot be accurately sampled from the drums, but an approximate
+sample can be obtained by means of the sectional sampler, which will
+allow a complete vertical section of the glycerine to be taken including
+any deposit.</p>
+
+
+<h3>ANALYSIS.</h3>
+
+<p>1. <i>Determination of Free Caustic Alkali.</i>&mdash;Put 20 grams of the sample
+into a 100 cc. flask, dilute with approximately 50 cc. of freshly boiled
+distilled water, add an excess of neutral barium chloride solution, 1
+cc. of phenolphthalein solution, make up to the mark and mix. Allow the
+precipitate to settle, draw off 50 cc. of the clear liquid and titrate
+with normal acid (<i>N</i>/1). Calculate the percentage of Na<sub>2</sub>O existing
+as caustic alkali.</p>
+
+<p>2. <i>Determination of Ash and Total Alkalinity.</i>&mdash;Weigh<span class='pagenum'><a name="Page_152" id="Page_152">[Pg 152]</a></span> 2 to 5 grams of
+the sample in a platinum dish, burn off the glycerine over a luminous
+Argand burner or other source of heat,<a name="FNanchor_19_19" id="FNanchor_19_19"></a><a href="#Footnote_19_19" class="fnanchor">[19]</a> giving a low temperature, to
+avoid volatilization and the formation of sulphides. When the mass is
+charred to the point that water will not be colored by soluble organic
+matter, lixiviate with hot distilled water, filter, wash and ignite the
+residue in the platinum dish. Return the filtrate and washings to the
+dish, evaporate the water, and carefully ignite without fusion. Weigh
+the ash.</p>
+
+<p>Dissolve the ash in distilled water and titrate total alkalinity, using
+as indicator methyl orange cold or litmus boiling.</p>
+
+<p>3. <i>Determination of Alkali Present as Carbonate.</i>&mdash;Take 10 grams of the
+sample, dilute with 50 cc. distilled water, add sufficient <i>N</i>/1 acid to
+neutralize the total alkali found at (2), boil under a reflux condenser
+for 15 to 20 minutes, wash down the condenser tube with distilled water,
+free from carbon dioxide, and then titrate back with <i>N</i>/1 NaOH, using
+phenolphthalein as indicator. Calculate the percentage of Na<sub>2</sub>O.
+Deduct the Na<sub>2</sub>O found in (1). The difference is the percentage of
+Na<sub>2</sub>O existing as carbonate.</p>
+
+<p>4. <i>Alkali Combined with Organic Acids.</i>&mdash;The sum of the percentages of
+Na<sub>2</sub>O found at (1) and (3) deducted from the percentage found at (2)
+is a measure of the Na<sub>2</sub>O or other alkali combined with organic acids.</p>
+
+<p>5. <i>Determination of Acidity.</i>&mdash;Take 10 grams of the sample, dilute with
+50 cc. distilled water free from carbon dioxide, and titrate with <i>N</i>/1
+NaOH and phenolphthalein. Express in terms of Na<sub>2</sub>O required to
+neutralize 100 grams.</p>
+
+<p>6. <i>Determination of Total Residue at 160&deg; C.</i>&mdash;For this determination
+the crude glycerine should be slightly alkaline with Na<sub>2</sub>CO<sub>3</sub> not
+<span class='pagenum'><a name="Page_153" id="Page_153">[Pg 153]</a></span>exceeding 0.2 per cent. Na<sub>2</sub>O, in order to prevent loss of organic
+acids. To avoid the formation of polyglycerols this alkalinity must not
+be exceeded.</p>
+
+<p>Ten grams of the sample are put into a 100 cc. flask, diluted with water
+and the calculated quantity of <i>N</i>/1 HCl or Na<sub>2</sub>CO<sub>3</sub> added to give
+the required degree of alkalinity. The flask is filled to 100 cc., the
+contents mixed, and 10 cc. measured into a weighed Petrie or similar
+dish 2.5 in. in diameter and 0.5 in. deep, which should have a flat
+bottom. In the case of crude glycerine abnormally high in organic
+residue a smaller amount should be taken, so that the weight of the
+organic residue does not materially exceed 30 to 40 milligrams.</p>
+
+<p>The dish is placed on a water bath (the top of the 160&deg; oven acts
+equally well) until most of the water has evaporated. From this point
+the evaporation is effected in the oven. Satisfactory results are
+obtained in an oven<a name="FNanchor_20_20" id="FNanchor_20_20"></a><a href="#Footnote_20_20" class="fnanchor">[20]</a> measuring 12 ins. cube, having an iron plate
+0.75 in. thick lying on the bottom to distribute the heat. Strips of
+asbestos millboard are placed on a shelf half way up the oven. On these
+strips the dish containing the glycerine is placed.</p>
+
+<p>If the temperature of the oven has been adjusted to 160&deg; C. with the
+door closed, a temperature of 130&deg; to 140&deg; can be readily maintained
+with the door partially open, and the glycerine, or most of it, should
+be evaporated off at this temperature. When only a slight vapor is seen
+to come off, the dish is removed and allowed to cool.</p>
+
+<p>An addition of 0.5 to 1.0 cc. of water is made, and by<span class='pagenum'><a name="Page_154" id="Page_154">[Pg 154]</a></span> a rotary motion
+the residue brought wholly or nearly into solution. The dish is then
+allowed to remain on a water bath or top of the oven until the excess
+water has evaporated and the residue is in such a condition that on
+returning to the oven at 160&deg; C. it will not spurt. The time taken up to
+this point cannot be given definitely, nor is it important. Usually two
+or three hours are required. From this point, however, the schedule of
+time must be strictly adhered to. The dish is allowed to remain in the
+oven, the temperature of which is carefully maintained at 160&deg; C. for
+one hour, when it is removed, cooled, the residue treated with water,
+and the water evaporated as before. The residue is then subjected to a
+second baking of one hour, after which the dish is allowed to cool in a
+desiccator over sulphuric acid and weighed. The treatment with water,
+etc., is repeated until a constant loss of 1 to 1.5 mg. per hour is
+obtained.</p>
+
+<p>In the case of acid glycerine a correction must be made for the alkali
+added 1 cc. <i>N</i>/1 alkali represents an addition of 0.03 gram. In the
+case of alkaline crudes a correction should be made for the acid added.
+Deduct the increase in weight due to the conversion of the NaOH and
+Na<sub>2</sub>CO<sub>3</sub> to NaCl. The corrected weight multiplied by 100 gives the
+percentage of <i>total residue at 160&deg; C.</i></p>
+
+<p>This residue is taken for the determination of the non-volatile
+acetylizable impurities (see acetin method).</p>
+
+<p>7. <i>Organic residue.</i>&mdash;Subtract the ash from the total residue at 160&deg;
+C. Report as organic residue at 160&deg; C. (it should be noted that
+alkaline salts of fatty acids are converted to carbonates on ignition
+and that the CO<sub>3</sub> thus derived is not included in the organic
+residue).<span class='pagenum'><a name="Page_155" id="Page_155">[Pg 155]</a></span></p>
+
+
+<h3>ACETIN PROCESS FOR THE DETERMINATION OF GLYCEROL.</h3>
+
+<p>This process is the one agreed upon at a conference of delegates from
+the British, French, German and American committees, and has been
+confirmed by each of the above committees as giving results nearer to
+the truth than the bichromate method on crudes in general. It is the
+process to be used (if applicable) whenever only one method is employed.
+On pure glycerines the results are identical with those obtained by the
+bichromate process. For the application of this method the crude
+glycerine should not contain over 60 per cent. water.</p>
+
+
+<h3>REAGENTS REQUIRED.</h3>
+
+<p>(<i>A</i>) <i>Best Acetic Anhydride.</i>&mdash;This should be carefully selected. A
+good sample must not require more than 0.1 cc. normal NaOH for
+saponification of the impurities when a blank is run on 7.5 cc. Only a
+slight color should develop during digestion of the blank.</p>
+
+<p>The anhydride may be tested for strength by the following method: Into a
+weighed stoppered vessel, containing 10 to 20 cc. of water, run about 2
+cc. of the anhydride, replace the stopper and weigh. Let stand with
+occasional shaking, for several hours, to permit the hydrolysis of all
+the anhydride; then dilute to about 200 cc., add phenolphthalein and
+titrate with <i>N</i>/1 NaOH. This gives the total acidity due to free acetic
+acid and acid formed from the anhydride. It is worthy of note that in
+the presence of much free anhydride a compound is formed with
+phenolphthalein, soluble in alkali and acetic acid, but insoluble in
+neutral solutions. If a turbidity is noticed toward the end of the
+neutralization it is an indication that the anhydride is incompletely
+hydrolyzed and inasmuch as the indicator is withdrawn from the solution,
+results may be incorrect.<span class='pagenum'><a name="Page_156" id="Page_156">[Pg 156]</a></span></p>
+
+<p>Into a stoppered weighing bottle containing a known weight of recently
+distilled aniline (from 10 to 20 cc.) measure about 2 cc. of the sample,
+stopper, mix, cool and weigh. Wash the contents into about 200 cc. of
+cold water, and titrate the acidity as before. This yields the acidity
+due to the original, preformed, acetic acid plus one-half the acid due
+to anhydride (the other half having formed acetanilide); subtract the
+second result from the first (both calculated to 100 grams) and double
+the result, obtaining the cc. <i>N</i>/1 NaOH per 100 grams of the sample. 1
+cc. <i>N</i>/NaOH equals 0.0510 anhydride.</p>
+
+<p>(<i>B</i>) <i>Pure Fused Sodium Acetate.</i>&mdash;The purchased salt is again
+completely fused in a platinum, silica or nickel dish, avoiding
+charring, powdered quickly and kept in a stoppered bottle or desiccator.
+It is most important that the sodium acetate be anhydrous.</p>
+
+<p>(<i>C</i>) <i>A Solution of Caustic Soda for Neutralizing, of about N</i>/1
+<i>Strength, Free from Carbonate.</i>&mdash;This can be readily made by dissolving
+pure sodium hydroxide in its own weight of water (preferably water free
+from carbon dioxide) and allowing to settle until clear, or filtering
+through an asbestos or paper filter. The clear solution is diluted with
+water free from carbon dioxide to the strength required.</p>
+
+<p>(<i>D</i>) <i>N</i>/1 <i>Caustic Soda Free from Carbonate.</i>&mdash;Prepared as above and
+carefully standardized. Some caustic soda solutions show a marked
+diminution in strength after being boiled; such solutions should be
+rejected.</p>
+
+<p>(<i>E</i>) <i>N</i>/1 <i>Acid.</i>&mdash;Carefully standardized.</p>
+
+<p>(<i>F</i>) <i>Phenolphthalein Solution.</i>&mdash;0.5 per cent. phenolphthalein in
+alcohol and neutralized.</p>
+
+
+<h3>THE METHOD.</h3>
+
+<p>In a narrow-mouthed flask (preferably round-bottomed),<span class='pagenum'><a name="Page_157" id="Page_157">[Pg 157]</a></span> capacity about
+120 cc., which has been thoroughly cleaned and dried, weigh accurately
+and as rapidly as possible 1.25 to 1.5 grams of the glycerine. A Grethan
+or Lunge pipette will be found convenient. Add about 3 grams of the
+anhydrous sodium acetate, then 7.5 cc. of the acetic anhydride, and
+connect the flask with an upright Liebig condenser. For convenience the
+inner tube of this condenser should not be over 50 cm. long and 9 to 10
+mm. inside diameter. The flask is connected to the condenser by either a
+ground glass joint (preferably) or a rubber stopper. If a rubber stopper
+is used it should have had a preliminary treatment with hot acetic
+anhydride vapor.</p>
+
+<p>Heat the contents and keep just boiling for one hour, taking precautions
+to prevent the salts drying on the sides of the flask.</p>
+
+<p>Allow the flask to cool somewhat, and through the condenser tube add 50
+cc. of distilled water free from carbon dioxide at a temperature of
+about 80&deg; C., taking care that the flask is not loosened from the
+condenser. The object of cooling is to avoid any sudden rush of vapors
+from the flask on adding water, and to avoid breaking the flask. Time is
+saved by adding the water before the contents of the flask solidify, but
+the contents may be allowed to solidify and the test proceeded with the
+next day without detriment, bearing in mind that the anhydride in excess
+is much more effectively hydrolyzed in hot than in cold water. The
+contents of the flask may be warmed to, but must not exceed, 80&deg; C.,
+until the solution is complete, except a few dark flocks representing
+organic impurities in the crude. By giving the flask a rotary motion,
+solution is more quickly effected.</p>
+
+<p>Cool the flask and contents without loosening from the condenser. When
+quite cold wash down the inside of the condenser tube, detach the flask,
+wash off the stopper or<span class='pagenum'><a name="Page_158" id="Page_158">[Pg 158]</a></span> ground glass connection into the flask, and
+filter the contents through an acid-washed filter into a Jena glass
+flask of about 1 litre capacity. Wash thoroughly with cold distilled
+water free from carbon dioxide. Add 2 cc. of phenolphthalein solution
+(<i>F</i>), then run in caustic soda solution (<i>C</i>) or (<i>D</i>) until a faint
+pinkish yellow color appears throughout the solution. This
+neutralization must be done most carefully; the alkali should be run
+down the sides of the flask, the contents of which are kept rapidly
+swirling with occasional agitation or change of motion until the
+solution is nearly neutralized, as indicated by the slower disappearance
+of the color developed locally by the alkali running into the mixture.
+When this point is reached the sides of the flask are washed down with
+carbon dioxide-free water and the alkali subsequently added drop by
+drop, mixing after each drop until the desired tint is obtained.</p>
+
+<p>Now run in from a burette 50 cc. or a calculated excess of <i>N</i>/1 NaOH
+(<i>D</i>) and note carefully the exact amount. Boil gently for 15 minutes,
+the flask being fitted with a glass tube acting as a partial condenser.
+Cool as quickly as possible and titrate the excess of NaOH with <i>N</i>/1
+acid (<i>E</i>) until the pinkish yellow or chosen end-point color just
+remains.<a name="FNanchor_21_21" id="FNanchor_21_21"></a><a href="#Footnote_21_21" class="fnanchor">[21]</a> A further addition of the indicator at this point will
+cause an increase of the pink color; this must be neglected, and the
+first end-point taken.</p>
+
+<p>From the <i>N</i>/1 NaOH consumed calculate the percentage of glycerol
+(including acetylizable impurities) after making the correction for the
+blank test described below.</p>
+
+<p>1 cc. <i>N</i>/1 NaOH = 0.03069 gram glycerol.</p>
+
+<p>The coefficient of expansion for normal solutions is<span class='pagenum'><a name="Page_159" id="Page_159">[Pg 159]</a></span> 0.00033 per cc.
+for each degree centigrade. A correction should be made on this account
+if necessary.</p>
+
+<p><i>Blank Test.</i>&mdash;As the acetic anhydride and sodium acetate may contain
+impurities which affect the result, it is necessary to make a blank
+test, using the same quantities of acetic anhydride, sodium acetate and
+water as in the analysis. It is not necessary to filter the solution of
+the melt in this case, but sufficient time must be allowed for the
+hydrolysis of the anhydride before proceeding with the neutralization.
+After neutralization it is not necessary to add more than 10 cc. of the
+<i>N</i>/1 alkali (<i>D</i>), as this represents the excess usually present after
+the saponification of the average soap lye crude. In determining the
+acid equivalent of the <i>N</i>/1 NaOH, however, the entire amount taken in
+the analysis, 50 cc., should be titrated after dilution with 300 cc.
+water free from carbon dioxide and without boiling.</p>
+
+<p><i>Determination of the Glycerol Value of the Acetylizable
+Impurities.</i>&mdash;The total residue at 160&deg; C. is dissolved in 1 or 2 cc. of
+water, washed into the acetylizing flask and evaporated to dryness. Then
+add anhydrous sodium acetate and acetic anhydride in the usual amounts
+and proceed as described in the regular analysis. After correcting for
+the blank, calculate the result to glycerol.</p>
+
+
+<h3>WAYS OF CALCULATING ACTUAL GLYCEROL CONTENT.</h3>
+
+<p>(1) Determine the apparent percentage of glycerol in the sample by the
+acetin process as described. The result will include acetylizable
+impurities if any are present.</p>
+
+<p>(2) Determine the total residue at 160&deg; C.</p>
+
+<p>(3) Determine the acetin value of the residue at (2) in terms of
+glycerol.</p>
+
+<p>(4) Deduct the result found at (3) from the percentage obtained at (1)
+and report this corrected figure as<span class='pagenum'><a name="Page_160" id="Page_160">[Pg 160]</a></span> glycerol. If volatile acetylizable
+impurities are present these are included in this figure.</p>
+
+<p>Trimethyleneglycol is more volatile than glycerine and can therefore be
+concentrated by fractional distillation. An approximation to the
+quantity can be obtained from the spread between the acetin and
+bichromate results on such distillates. The spread multiplied by 1.736
+will give the glycol.</p>
+
+
+<h3>BICHROMATE PROCESS FOR GLYCEROL DETERMINATION. REAGENTS REQUIRED.</h3>
+
+<p>(<i>A</i>) <i>Pure potassium bichromate</i> powdered and dried in air free from
+dust or organic vapors, at 110&deg; to 120&deg; C. This is taken as the
+standard.</p>
+
+<p>(<i>B</i>) <i>Dilute Bichromate Solution.</i>&mdash;7.4564 grams of the above
+bichromate are dissolved in distilled water and the solution made up to
+one liter at 15.5&deg; C.</p>
+
+<p>(<i>C</i>) <i>Ferrous Ammonium Sulphate.</i>&mdash;It is never safe to assume this salt
+to be constant in composition and it must be standardized against the
+bichromate as follows: dissolve 3.7282 grams of bichromate (<i>A</i>) in 50
+cc. of water. Add 50 cc. of 50 per cent. sulphuric acid (by volume), and
+to the cold undiluted solution add from a weighing bottle a moderate
+excess of the ferrous ammonium sulphate, and titrate back with the
+dilute bichromate (<i>B</i>). Calculate the value of the ferrous salt in
+terms of bichromate.</p>
+
+<p>(<i>D</i>) <i>Silver Carbonate.</i>&mdash;This is prepared as required for each test
+from 140 cc. of 0.5 per cent. silver sulphate solution by precipitation,
+with about 4.9 cc. <i>N</i>/1 sodium carbonate solution (a little less than
+the calculated quantity of <i>N</i>/1 sodium carbonate should be used as an
+excess to prevent rapid settling). Settle, decant and wash one by
+decantation.</p>
+
+<p>(<i>E</i>) <i>Subacetate of Lead.</i>&mdash;Boil a 10 per cent. solution<span class='pagenum'><a name="Page_161" id="Page_161">[Pg 161]</a></span> of pure lead
+acetate with an excess of litharge for one hour, keeping the volume
+constant, and filter while hot. Disregard any precipitate which
+subsequently forms. Preserve out of contact with carbon dioxide.</p>
+
+<p>(<i>F</i>) <i>Potassium Ferricyanide.</i>&mdash;A very dilute, freshly prepared
+solution containing about 0.1 per cent.</p>
+
+
+<h3>THE METHOD.</h3>
+
+<p>Weigh 20 grams of the glycerine, dilute to 250 cc. and take 25 cc. Add
+the silver carbonate, allow to stand, with occasional agitation, for
+about 10 minutes, and add a slight excess (about 5 cc. in most cases) of
+the basic lead acetate (<i>E</i>), allow to stand a few minutes, dilute with
+distilled water to 100 cc., and then add 0.15 cc. to compensate for the
+volume of the precipitate, mix thoroughly, filter through an air-dry
+filter into a suitable narrow-mouthed vessel, rejecting the first 10
+cc., and return the filtrate if not clear and bright. Test a portion of
+the filtrate with a little basic lead acetate, which should produce no
+further precipitate (in the great majority of cases 5 cc. are ample, but
+occasionally a crude will be found requiring more, and in this case
+another aliquot of 25 cc. of the dilute glycerine should be taken and
+purified with 6 cc. of the basic acetate). Care must be taken to avoid a
+marked excess of basic acetate.</p>
+
+<p>Measure off 25 cc. of the clear filtrate into a flask or beaker
+(previously cleaned with potassium bichromate and sulphuric acid). Add
+12 drops of sulphuric acid (1: 4) to precipitate the small excess of
+lead as sulphate. Add 3.7282 grams of the powdered potassium bichromate
+(<i>A</i>). Rinse down the bichromate with 25 cc. of water and let stand with
+occasional shaking until all the bichromate is dissolved (no reduction
+will take place in the cold).</p>
+
+<p>Now add 50 cc. of 50 per cent. sulphuric acid (by volume)<span class='pagenum'><a name="Page_162" id="Page_162">[Pg 162]</a></span> and immerse
+the vessel in boiling water for two hours and keep protected from dust
+and organic vapors, such as alcohol, till the titration is completed.
+Add from a weighing bottle a slight excess of the ferrous ammonium
+sulphate (<i>C</i>), making spot tests on a porcelain plate with the
+potassium ferricyanide (<i>F</i>). Titrate back with the dilute bichromate.
+From the amount of bichromate reduced calculate the percentage of
+glycerol.</p>
+
+<p>1 gram glycerol = 7.4564 grams bichromate.</p>
+
+<p>1 gram bichromate = 0.13411 gram glycerol.</p>
+
+<p>The percentage of glycerol obtained above includes any oxidizable
+impurities present after the purification. A correction for the
+non-volatile impurities may be made by running a bichromate test on the
+residue at 160&deg; C.</p>
+
+
+<h3>NOTES.</h3>
+
+<p>(1) It is important that the concentration of acid in the oxidation
+mixture and the time of oxidation should be strictly adhered to.</p>
+
+<p>(2) Before the bichromate is added to the glycerine solution it is
+essential that the slight excess of lead be precipitated with sulphuric
+acid, as stipulated.</p>
+
+<p>(3) For crudes practically free from chlorides the quantity of silver
+carbonate may be reduced to one-fifth and the basic lead acetate to 0.5
+cc.</p>
+
+<p>(4) It is sometimes advisable to add a little potassium sulphate to
+insure a clear filtrate.</p>
+
+
+<h3>SAMPLING CRUDE GLYCERINE.</h3>
+
+<p>The usual method of sampling crude glycerine hitherto has been by means
+of a glass tube, which is slowly lowered into the drum with the object
+of taking as nearly as possible a vertical section of the glycerine
+contained in the<span class='pagenum'><a name="Page_163" id="Page_163">[Pg 163]</a></span> drum. This method has been found unsatisfactory, owing
+to the fact that in cold climates glycerine runs into the tube very
+slowly, so that, owing to the time occupied, it is impossible to take a
+complete section of the crude. Another objection to the glass tube is
+that it fails to take anything approaching a correct proportion of any
+settled salt contained in the drum.</p>
+
+<p>The sampler which is illustrated herewith has been devised with the
+object of overcoming the objections to the glass tube as far as
+possible. It consists of two brass tubes, one fitting closely inside the
+other. A number of ports are cut out in each tube in such a way that
+when the ports are opened a continuous slot is formed which enables a
+complete section to be taken throughout the entire length of the drum.
+By this arrangement the glycerine fills into the sampler almost
+instantaneously. There are a number of ports cut at the bottom of the
+sampler which render it possible to take a proportion of the salt at the
+bottom of the drum. The instrument is so constructed that all the ports,
+including the bottom ones, can be closed simultaneously by the simple
+action of turning the handle at the top; a pointer is arranged which
+indicates on a dial when the sampler is open or closed. In samplers of
+larger section (1 in.) it is possible to arrange a third motion whereby
+the bottom ports only are open for emptying, but in samplers of smaller
+dimensions (5/8 in.) this third motion must be dispensed with, otherwise
+the dimensions of the ports have to be so small that the sampler would
+not be efficient.</p>
+
+<p>In using the sampler it is introduced into the drum with the ports
+closed, and when it has touched the bottom, the ports are opened for a
+second or two, then closed and withdrawn, and the sample discharged into
+the receiving vessel by opening the ports. When the drum contains salt
+which<span class='pagenum'><a name="Page_164" id="Page_164">[Pg 164]</a></span> has deposited, the ports must be opened before the sampler is
+pushed through the salt, thus enabling a portion to be included in the
+sample. It is, however, almost impossible to obtain a correct proportion
+of salt after it has settled in the drum and it is therefore recommended
+that the drum be sampled before any salt has deposited. A sampler 1 in.
+in diameter withdraws approximately 10 oz. from a 110-gal. drum. A
+sampler 5/8 in. in diameter will withdraw about 5 oz.</p>
+
+<div class="footnotes"><h3>FOOTNOTES:</h3>
+
+<div class="footnote"><p><a name="Footnote_13_13" id="Footnote_13_13"></a><a href="#FNanchor_13_13"><span class="label">[13]</span></a> Zeit. Angew. Chem. 19, 385 (1906).</p></div>
+
+<div class="footnote"><p><a name="Footnote_14_14" id="Footnote_14_14"></a><a href="#FNanchor_14_14"><span class="label">[14]</span></a> Zeit. Angew. Chem. 27, 11-20 (1914).</p></div>
+
+<div class="footnote"><p><a name="Footnote_15_15" id="Footnote_15_15"></a><a href="#FNanchor_15_15"><span class="label">[15]</span></a> Bull. 107, Bur. Chem. U. S. Dept. Agriculture.</p></div>
+
+<div class="footnote"><p><a name="Footnote_16_16" id="Footnote_16_16"></a><a href="#FNanchor_16_16"><span class="label">[16]</span></a> Richards and Gies, Am. J. Physiol. (1902) 7, 129.</p></div>
+
+<div class="footnote"><p><a name="Footnote_17_17" id="Footnote_17_17"></a><a href="#FNanchor_17_17"><span class="label">[17]</span></a> Seifensieder Ztg. (1913) No. 46.</p></div>
+
+<div class="footnote"><p><a name="Footnote_18_18" id="Footnote_18_18"></a><a href="#FNanchor_18_18"><span class="label">[18]</span></a> Bull 107, Bur. Chem. U. S. Dept. Agriculture.</p></div>
+
+<div class="footnote"><p><a name="Footnote_19_19" id="Footnote_19_19"></a><a href="#FNanchor_19_19"><span class="label">[19]</span></a> Carbon is readily burned off completely, without loss of
+chlorides, in a gas-heated muffle furnace adjusted to a dull red heat.</p></div>
+
+<div class="footnote"><p><a name="Footnote_20_20" id="Footnote_20_20"></a><a href="#FNanchor_20_20"><span class="label">[20]</span></a> An electric oven suitable for this work, which is readily
+adjusted to 160 degs. C., has been made for Mr. Low and the chairman, by
+the Apparatus and Specialty Company, Lansing, Mich. Its size is 9-1/2 &times;
+10 &times; 16 inches, and capacity 8 Petrie dishes. It gives a strong draft at
+constant temperature.</p></div>
+
+<div class="footnote"><p><a name="Footnote_21_21" id="Footnote_21_21"></a><a href="#FNanchor_21_21"><span class="label">[21]</span></a> A precipitate at this point is an indication of the
+presence of iron or alumina, and high results will be obtained unless a
+correction is made as described below.</p></div>
+</div>
+
+
+<hr style="width: 65%;" /><p><span class='pagenum'><a name="Page_165" id="Page_165">[Pg 165]</a></span></p>
+<h2>CHAPTER VII</h2>
+
+<h3>Standard Methods for the Sampling and Analysis of Commercial Fats and
+Oils<a name="FNanchor_22_22" id="FNanchor_22_22"></a><a href="#Footnote_22_22" class="fnanchor">[22]</a></h3>
+
+
+<p>The following report of the <i>Committee on Analysis of Commercial Fats
+and Oils</i> of the <i>Division of Industrial Chemists and Chemical
+Engineers</i> of the American Chemical Society was adopted April 14, 1919,
+by unanimous vote:</p>
+
+<p>
+<span class="smcap">W. D. Richardson</span>, <i>Chairman</i>,
+Swift and Co., Chicago, Ill.</p>
+
+<p><span class="smcap">R. W. Bailey</span>,
+Stillwell and Gladding, New York City.</p>
+
+<p><span class="smcap">W. J. Gascoyne</span>,
+W. J. Gascoyne and Co., Baltimore, Md.</p>
+
+<p><span class="smcap">I. Katz</span>,[A]
+Wilson and Co., Chicago, Ill.</p>
+
+<p><span class="smcap">A. Lowenstein</span>,[A]
+Morris and Co., Chicago, Ill.</p>
+
+<p><span class="smcap">H. J. Morrison</span>,
+Proctor and Gamble Co.,
+Ivorydale, Ohio.</p>
+
+<p><span class="smcap">J. R. Powell</span>,
+Armour Soap Works, Chicago, Ill.</p>
+
+<p><span class="smcap">R. J. Quinn</span>,[A]
+Midland Chemical Co., Argo, Ill.</p>
+
+<p><span class="smcap">Paul Rudnick</span>,
+Armour and Co., Chicago, Ill.</p>
+
+<p><span class="smcap">L. M. Tolman</span>,
+Wilson and Co., Chicago, Ill.</p>
+
+<p><span class="smcap">E. Twitchell</span>,[A]
+Emery Candle Co., Cincinnati, Ohio.</p>
+
+<p><span class="smcap">J. J. Vollertsen</span>,
+Morris and Co., Chicago, Ill.
+</p>
+
+<p>[Note A: Resigned.]</p>
+
+
+<h3>Scope, Applicability and Limitations of the Methods.</h3>
+
+
+<h4>SCOPE.</h4>
+
+<p>These methods are intended to aid in determining the commercial
+valuation of fats and fatty oils in their purchase and sale, based on
+the fundamental assumption commonly recognized in the trade, namely,
+that the product is true to name and is not adulterated. For methods for
+determining the identity of oils and fats, the absence of adulterants
+therein and for specific tests used in particular industries, the
+chemist is referred to standard works on the analysis of fats and oils.<span class='pagenum'><a name="Page_166" id="Page_166">[Pg 166]</a></span></p>
+
+
+<h4>APPLICABILITY.</h4>
+
+<p>The methods are applicable in commercial transactions involving fats and
+fatty oils used in the soap, candle and tanning industries, to edible
+fats and oils and to fats and fatty oils intended for lubricating and
+burning purposes. The methods are applicable to the raw oils used in the
+varnish and paint industry with the exceptions noted under limitations,
+but special methods have not been included.</p>
+
+
+<h4>LIMITATIONS.</h4>
+
+<p>The methods have not been developed with special reference to waxes
+(beeswax, carnauba wax, wool wax, etc.) although some of them may be
+found applicable to these substances. The Committee considers the Wijs
+method superior to the Hanus method for the determination of iodine
+number of linseed oil as well as other oils, although the Hanus method
+has been considered standard for this work for some time and has been
+adopted by the American Society for Testing Materials and in various
+specifications. It has been customary to use the H&uuml;bl method for the
+determination of iodine value of tung oil (China wood oil) but the
+Committee's work indicates that the Wijs method is satisfactory for this
+determination.</p>
+
+
+<h3>Sampling.</h3>
+
+
+<h4>TANK CARS.</h4>
+
+<p>1. <span class="smcap">Sampling While Loading</span>&mdash;Sample shall be taken at discharge of pipe
+where it enters tank car dome. The total sample taken shall be not less
+than 50 lbs. and shall be a composite of small samples of about 1 pound
+each, taken at regular intervals during the entire period of loading.</p>
+
+<p>The sample thus obtained is thoroughly mixed and uniform 3-lb. portions
+placed in air-tight 3-lb. metal containers. At least three such samples
+shall be put up, one for the buyer, one for the seller, and the third to
+be sent to a<span class='pagenum'><a name="Page_167" id="Page_167">[Pg 167]</a></span> referee chemist in case of dispute. All samples are to be
+promptly and correctly labeled and sealed.</p>
+
+<p>2. <span class="smcap">Sampling from Car on Track</span><a name="FNanchor_23_23" id="FNanchor_23_23"></a><a href="#Footnote_23_23" class="fnanchor">[23]</a>&mdash;(<i>a</i>) <i>When contents are solid.</i><a name="FNanchor_24_24" id="FNanchor_24_24"></a><a href="#Footnote_24_24" class="fnanchor">[24]</a>
+In this case the sample is taken by means of a large tryer measuring
+about 2 in. across and about 1-1/2 times the depth of the car in length.
+Several tryerfuls are taken vertically and obliquely toward the ends of
+the car until 50 lbs. are accumulated, when the sample is softened,
+mixed and handled as under (1). In case the contents of the tank car
+have assumed a very hard condition, as in Winter weather, so that it is
+impossible to insert the tryer, and it becomes necessary to soften the
+contents of the car by means of the closed steam coil (in nearly all
+tank cars the closed steam coil leaks) or by means of open steam in
+order to draw a proper sample, suitable arrangements must be made
+between buyer and seller for the sampling of the car after it is
+sufficiently softened, due consideration being given to the possible
+presence of water in the material in the car as received and also to the
+possible addition of water during the steaming. The Committee knows of
+no direct method for sampling a hard-frozen tank car of tallow in a
+satisfactory manner.</p>
+
+<p>(<i>b</i>) <i>When contents are liquid.</i> The sample taken is to be a 50-lb.
+composite made up of numerous small samples taken from the top, bottom
+and intermediate points by means of a bottle or metal container with
+removable stopper or top. This device attached to a suitable pole is
+lowered to the various desired depths, when the stopper or top is
+removed and the container allowed to fill. The 50-lb. sample thus
+obtained is handled as under (1).<span class='pagenum'><a name="Page_168" id="Page_168">[Pg 168]</a></span></p>
+
+<p>In place of the device described above, any sampler capable of taking a
+sample from the top, bottom, and center, or from a section through car,
+may be used.</p>
+
+<p>(<i>c</i>) <i>When contents are in semi-solid condition, or when stearine has
+separated from liquid portions.</i> In this case, a combination of (<i>a</i>)
+and (<i>b</i>) may be used or by agreement of the parties the whole may be
+melted and procedure (<i>b</i>) followed.</p>
+
+
+<h4>BARRELS, TIERCES, CASKS, DRUMS, AND OTHER PACKAGES.</h4>
+
+<p>All packages shall be sampled, unless by special agreement the parties
+arrange to sample a lesser number; but in any case not less than 10 per
+cent of the total number shall be sampled. The total sample taken shall
+be at least 20 lbs. in weight for each 100 barrels, or equivalent.</p>
+
+<p>1. <span class="smcap">Barrels, Tierces and Casks</span>&mdash;(<i>a</i>) <i>When contents are solid.</i> The
+small samples shall be taken by a tryer through the bunghole or through
+a special hole bored in the head or side for the purpose, with a 1-in.
+or larger auger. Care should be taken to avoid and eliminate all borings
+and chips from the sample. The tryer is inserted in such a way as to
+reach the head of the barrel, tierce, or cask. The large sample is
+softened, mixed and handled according to <span class="smcap">tank cars</span> (1).</p>
+
+<p>(<i>b</i>) <i>When contents are liquid.</i> In this case use is made of a glass
+tube with constricted lower end. This is inserted slowly and allowed to
+fill with the liquid, when the upper end is closed and the tube
+withdrawn, the contents being allowed to drain into the sample
+container. After the entire sample is taken it is thoroughly mixed and
+handled according to <span class="smcap">tank cars</span> (1).</p>
+
+<p>(<i>c</i>) <i>When contents are semi-solid.</i> In this case the tryer or a glass
+tube with larger outlet is used, depending on the degree of fluidity.<span class='pagenum'><a name="Page_169" id="Page_169">[Pg 169]</a></span></p>
+
+<p>(<i>d</i>) <i>Very hard materials, such as natural and artificial stearines.</i>
+By preference the barrels are stripped and samples obtained by breaking
+up contents of at least 10 per cent of the packages. This procedure is
+to be followed also in the case of cakes shipped in sacks. When shipped
+in the form of small pieces in sacks they can be sampled by grab
+sampling and quartering. In all cases the final procedure is as outlined
+under <span class="smcap">tank cars</span> (1).</p>
+
+<p>2. <span class="smcap">Drums</span>&mdash;Samples are to be taken as under (1), use being made of the
+bunghole. The tryer or tube should be sufficiently long to reach to the
+ends of the drum.</p>
+
+<p>3. <span class="smcap">Other Packages</span>&mdash;Tubs, pails and other small packages not mentioned
+above are to be sampled by tryer or tube (depending on fluidity) as
+outlined above, the tryer or tube being inserted diagonally whenever
+possible.</p>
+
+<p>4. <span class="smcap">Mixed Lots and Packages</span>&mdash;When lots of tallow or other fats are
+received in packages of various shapes and sizes, and especially wherein
+the fat itself is of variable composition, such must be left to the
+judgment of the sampler. If variable, the contents of each package
+should be mixed as thoroughly as possible and the amount of the
+individual samples taken made proportional to the sizes of the packages.</p>
+
+
+<h3>Analysis.</h3>
+
+
+<h4>SAMPLE.</h4>
+
+<p>The sample must be representative and at least three pounds in weight
+and taken in accordance with the <span class="smcap">standard methods for the sampling of
+commercial fats and oils</span>. It must be kept in an air-tight container, in
+a dark, cool place.</p>
+
+<p>Soften the sample if necessary by means of a gentle heat, taking care
+not to melt it. When sufficiently softened, mix the sample thoroughly by
+means of a mechanical egg beater or other equally effective mechanical
+mixer.<span class='pagenum'><a name="Page_170" id="Page_170">[Pg 170]</a></span></p>
+
+
+<h4>MOISTURE AND VOLATILE MATTER.</h4>
+
+<p><span class="smcap">Apparatus</span>: <i>Vacuum Oven</i>&mdash;The Committee Standard Oven.</p>
+
+<p><span class="smcap">Description</span>&mdash;The Standard F. A. C. Vacuum Oven has been designed with
+the idea of affording a simple and compact vacuum oven which will give
+as uniform temperatures as possible on the shelf. As the figure shows,
+it consists of an iron casting of rectangular sections with hinged front
+door made tight by means of a gasket and which can be lowered on opening
+the oven so as to form a shelf on which samples may be rested. The oven
+contains but one shelf which is heated from above as well as below by
+means of resistance coils. Several thermometer holes are provided in
+order to ascertain definitely the temperature at different points on the
+shelf. In a vacuum oven where the heating is done almost entirely by
+radiation it is difficult to maintain uniform temperatures at all
+points, but the F. A. C. oven accomplishes this rather better than most
+vacuum ovens. Larger ovens containing more than one shelf have been
+tried by the Committee, but have been found to be lacking in temperature
+uniformity and means of control. The entire oven is supported by means
+of a 4-in. standard pipe which screws into the base of the oven and
+which in turn is supported by being screwed into a blind flange of
+suitable diameter which rests on the floor or work table.</p>
+
+<p><i>Moisture Dish</i>&mdash;A shallow, glass dish, lipped, beaker form,
+approximately 6 to 7 cm. diameter and 4 cm. deep, shall be standard.</p>
+
+<p><span class="smcap">Determination</span>&mdash;Weigh out 5 grams (= 0.2 g. of the prepared sample) into
+a moisture dish. Dry to constant weight in <i>vacuo</i> at a uniform
+temperature, not less than 15&deg; C. nor more than 20&deg; C. above the boiling
+point of water at the working pressure, which must not exceed 100 mm. of
+mercury.<a name="FNanchor_25_25" id="FNanchor_25_25"></a><a href="#Footnote_25_25" class="fnanchor">[25]</a> Constant weight is attained when successive dryings for
+1-hr. periods show an additional loss of not more that 0.05 per cent.
+Report loss in weight as <span class="smcap">moisture and volatile matter</span>.<a name="FNanchor_26_26" id="FNanchor_26_26"></a><a href="#Footnote_26_26" class="fnanchor">[26]</a><span class='pagenum'><a name="Page_171" id="Page_171">[Pg 171]</a></span></p>
+
+<div class="figcenter" style="width: 514px;">
+<img src="images/p171.jpg" width="514" height="480" alt="Standard Vacuum Oven" title="" />
+<span class="caption">Standard Vacuum Oven</span>
+</div><p><span class='pagenum'><a name="Page_172" id="Page_172">[Pg 172]</a></span></p>
+
+<p>The vacuum-oven method cannot be considered accurate in the case of fats
+of the coconut oil group containing free acid and the Committee
+recommends that it be used only for oils of this group when they contain
+less than 1 per cent free acid. In the case of oils of this group
+containing more than 1 per cent free acid, recourse should be had
+temporarily to the routine control method for moisture and volatile
+matter<a name="FNanchor_27_27" id="FNanchor_27_27"></a><a href="#Footnote_27_27" class="fnanchor">[27]</a> until the Committee develops a more satisfactory method.</p>
+
+<p>The air-oven method cannot be considered even approximately accurate in
+the case of the drying and semi-drying oils and those of the coconut oil
+group. Therefore, in the case of such oils as cottonseed oil, maize oil
+(corn oil), soy bean oil, linseed oil, coconut oil, palm kernel oil,
+etc., the vacuum-oven method should always be used, except in the case
+of fats of the coconut group containing more than 1 per cent free acid,
+as noted above.</p>
+
+
+<h4>INSOLUBLE IMPURITIES.</h4>
+
+<p>Dissolve the residue from the moisture and volatile matter determination
+by heating it on a steam bath with 50 cc. of kerosene. Filter the
+solution through a Gooch crucible properly prepared with asbestos,<a name="FNanchor_28_28" id="FNanchor_28_28"></a><a href="#Footnote_28_28" class="fnanchor">[28]</a>
+wash the insoluble matter five times with 10-cc. portions of hot
+kerosene, and finally wash the residual kerosene out thoroughly with
+petroleum ether. Dry the crucible and contents to constant weight, as in
+the determination of moisture and volatile matter and report results as
+<span class="smcap">insoluble impurities</span>.<span class='pagenum'><a name="Page_173" id="Page_173">[Pg 173]</a></span></p>
+
+
+<h4>SOLUBLE MINERAL MATTER.</h4>
+
+<p>Place the combined kerosene filtrate and kerosene washings from the
+insoluble impurities determination in a platinum dish. Place in this an
+ashless filter paper folded in the form of a cone, apex up. Light the
+apex of the cone, whereupon the bulk of the kerosene burns quietly. Ash
+the residue in a muffle, to constant weight, taking care that the
+decomposition of alkaline earth carbonates is complete, and report the
+result as <span class="smcap">soluble mineral matter</span>.<a name="FNanchor_29_29" id="FNanchor_29_29"></a><a href="#Footnote_29_29" class="fnanchor">[29]</a> When the percentage of soluble
+mineral matter amounts to more than 0.1 per cent, multiply the
+percentage by 10 and add this amount to the percentage of free fatty
+acids as determined.[30]<span class='pagenum'><a name="Page_174" id="Page_174">[Pg 174]</a></span></p>
+
+
+<h4>FREE FATTY ACIDS.</h4>
+
+<p>The <span class="smcap">alcohol</span><a name="FNanchor_31_31" id="FNanchor_31_31"></a><a href="#Footnote_31_31" class="fnanchor">[31]</a> used shall be approximately 95 per cent ethyl alcohol,
+freshly distilled from sodium hydroxide, which with phenolphthalein
+gives a definite and distinct end-point.</p>
+
+<p><span class="smcap">Determination</span>&mdash;Weigh 1 to 15 g. of the prepared sample into an
+Erlenmeyer flask, using the smaller quantity in the case of
+dark-colored, high acid fats. Add 50 to 100 cc. hot, neutral alcohol,
+and titrate with <i>N</i>/2, <i>N</i>/4 or <i>N</i>/10 sodium hydroxide depending on
+the fatty acid content, using phenolphthalein as indicator. Calculate to
+oleic acid, except that in the case of palm oil the results may also be
+expressed in terms of palmitic acid, clearly indicating the two methods
+of calculation in the report. In the case of coconut and palm kernel
+oils, calculate to and report in terms of lauric acid in addition to
+oleic acid, clearly indicating the two methods of calculation in the
+report. In the case of fats or greases containing more than 0.1 per cent
+of soluble mineral matter, add to the percentages of free fatty acids as
+determined 10 times the percentage of bases in the soluble mineral
+matter as determined.<a name="FNanchor_30_30" id="FNanchor_30_30"></a><a href="#Footnote_30_30" class="fnanchor">[30]</a> This addition gives the equivalent of fatty
+acids combined with the soluble mineral matter.<span class='pagenum'><a name="Page_175" id="Page_175">[Pg 175]</a></span></p>
+
+
+<h4>TITER.</h4>
+
+<p><span class="smcap">Standard Thermometer</span>&mdash;The thermometer is graduated at zero and in tenth
+degrees from 10&deg; C. to 65&deg; C., with one auxiliary reservoir at the upper
+end and another between the zero mark and the 10&deg; mark. The cavity in
+the capillary tube between the zero mark and the 10&deg; mark is at least 1
+cm. below the 10&deg; mark, the 10&deg; mark is about 3 or 4 cm. above the bulb,
+the length of the thermometer being about 37 cm. over all. The
+thermometer has been annealed for 75 hrs. at 450&deg; C. and the bulb is of
+Jena normal 16''' glass, or its equivalent, moderately thin, so that the
+thermometer will be quick-acting. The bulb is about 3 cm. long and 6 mm.
+in diameter. The stem of the thermometer is 6 mm. in diameter and made
+of the best thermometer tubing, with scale etched on the stem, the
+graduation is clear-cut and distinct, but quite fine. The thermometer
+must be certified by the U. S. Bureau of Standards.</p>
+
+<p><span class="smcap">Glycerol Caustic Solution</span>&mdash;Dissolve 250 g. potassium hydroxide in 1900
+cc. dynamite glycerin with the aid of heat.</p>
+
+<p><span class="smcap">Determination</span>&mdash;Heat 75 cc. of the glycerol-caustic solution to 150&deg; C.
+and add 50 g. of the melted fat. Stir the mixture well and continue
+heating until the melt is homogeneous, at no time allowing the
+temperature to exceed 150&deg; C. Allow to cool somewhat and carefully add
+50 cc. 30 per cent sulfuric acid. Now add hot water and heat until the
+fatty acids separate out perfectly clear. Draw off the acid water and
+wash the fatty acids with hot water until free from mineral acid, then
+filter and heat to 130&deg; C. as rapidly as possible while stirring.
+Transfer the fatty acids, when cooled somewhat, to a 1-in. by 4-in.
+titer tube, placed in a 16-oz. salt-mouth bottle of clear glass, fitted
+with a cork that is perforated so as to hold the tube rigidly when in
+position. Suspend the titer thermometer so that it can be<span class='pagenum'><a name="Page_176" id="Page_176">[Pg 176]</a></span> used as a
+stirrer and stir the fatty acids slowly (about 100 revolutions per
+minute) until the mercury remains stationary for 30 seconds. Allow the
+thermometer to hang quietly with the bulb in the center of the tube and
+report the highest point to which the mercury rises as the titer of the
+fatty acids. The titer should be made at about 20&deg; C. for all fats
+having a titer above 30&deg; C. and at 10&deg; C. below the titer for all other
+fats. Any convenient means may be used for obtaining a temperature of
+10&deg; below the titer of the various fats. The committee recommends first
+of all a chill room for this purpose; second, an artificially chilled
+small chamber with glass window; third, immersion of the salt-mouth
+bottle in water or other liquid of the desired temperature.</p>
+
+
+<h4>UNSAPONIFIABLE MATTER.</h4>
+
+<p><span class="smcap">Extraction Cylinder</span>&mdash;The cylinder shall be glass-stoppered, graduated at
+40 cc., 80 cc. and 130 cc., and of the following dimensions: diameter
+about 1-3/8 in., height about 12 in.</p>
+
+<p><span class="smcap">Petroleum Ether</span>&mdash;Redistilled petroleum ether, boiling under 75&deg; C.,
+shall be used. A blank must be made by evaporating 250 cc. with about
+0.25 g. of stearine or other hard fat (previously brought to constant
+weight by heating) and drying as in the actual determination. The blank
+must not exceed a few milligrams.</p>
+
+<p><span class="smcap">Determination</span>&mdash;Weigh 5 g. (&plusmn;0.20 g.) of the prepared sample into a
+200-cc. Erlenmeyer flask, add 30 cc. of redistilled 95 per cent
+(approximately) ethyl alcohol and 5 cc. of 50 per cent aqueous potassium
+hydroxide, and boil the mixture for one hour under a reflux condenser.
+Transfer to the extraction cylinder and wash to the 40-cc. mark with
+redistilled 95 per cent ethyl alcohol. Complete the transfer, first with
+warm, then with cold water, till the total volume amounts to 80 cc. Cool
+the cylinder and contents to room<span class='pagenum'><a name="Page_177" id="Page_177">[Pg 177]</a></span> temperature and add 50 cc. of
+petroleum ether. Shake <i>vigorously</i> for one minute and allow to settle
+until both layers are clear, when the volume of the upper layer should
+be about 40 cc. Draw off the petroleum ether layer as closely as
+possible by means of a slender glass siphon into a separatory funnel of
+500 cc. capacity. Repeat extraction at least four more times, using 50
+cc. of petroleum ether each time. More extractions than five are
+necessary where the unsaponifiable matter runs high, say over 5 per
+cent, and also in some cases where it is lower than 5 per cent, but is
+extracted with difficulty. Wash the combined extracts in a separatory
+funnel three times with 25-cc. portions of 10 per cent alcohol, shaking
+vigorously each time. Transfer the petroleum ether extract to a
+wide-mouth tared flask or beaker, and evaporate the petroleum ether on a
+steam bath in an air current. Dry as in the method for <span class="smcap">moisture and
+volatile matter</span>. Any blank must be deducted from the weight before
+calculating unsaponifiable matter. Test the final residue for solubility
+in 50 cc. petroleum ether at room temperature. Filter and wash free from
+the insoluble residue, if any, evaporate and dry in the same manner as
+before. The Committee wishes to emphasize the necessity of thorough and
+vigorous shaking in order to secure accurate results. The two phases
+must be brought into the most intimate contact possible, otherwise low
+and disagreeing results may be obtained.</p>
+
+
+<h4>IODINE NUMBER&mdash;WIJS METHOD.</h4>
+
+<p><span class="smcap">Preparation of Reagents</span>&mdash;<i>Wijs Iodine Solution</i>&mdash;Dissolve 13.0 g. of
+resublimed iodine in one liter of C. P. glacial acetic acid and pass in
+washed and dried chlorine gas until the original thiosulfate titration
+of the solution is not quite doubled. The solution is then preserved in
+amber glass-stoppered bottles, sealed with paraffin until ready for use.</p>
+
+<p>Mark the date on which the solution is prepared on the<span class='pagenum'><a name="Page_178" id="Page_178">[Pg 178]</a></span> bottle or
+bottles and do not use Wijs solution which is more than 30 days old.</p>
+
+<p>There should be no more than a slight excess of iodine, and no excess of
+chlorine. When the solution is made from iodine and chlorine, this point
+can be ascertained by not quite doubling the titration.<a name="FNanchor_32_32" id="FNanchor_32_32"></a><a href="#Footnote_32_32" class="fnanchor">[32]</a></p>
+
+<p>The glacial acetic acid used for preparation of the Wijs solution should
+be of 99.0 to 99.5 per cent strength. In case of glacial acetic acids of
+somewhat lower strength, the Committee recommends freezing and
+centrifuging or draining as a means of purification.</p>
+
+<p><i>N</i>/10 <i>Sodium Thiosulfate Solution</i>&mdash;Dissolve 24.8 g. of C. P. sodium
+thiosulfate in recently boiled distilled water and dilute with the same
+to one liter at the temperature at which the titrations are to be made.</p>
+
+<p><i>Starch Paste</i>&mdash;Boil 1 g. of starch in 200 cc. of distilled water for 10
+min. and cool to room temperature.</p>
+
+<p>An improved starch solution may be prepared by autoclaving 2 g. of
+starch and 6 g. of boric acid dissolved in 200 cc. water at 15 lbs.
+pressure for 15 min. This solution has good keeping qualities.<span class='pagenum'><a name="Page_179" id="Page_179">[Pg 179]</a></span></p>
+
+<p><i>Potassium Iodide Solution</i>&mdash;Dissolve 150 g. of potassium iodide in
+water and make up to one liter.</p>
+
+<p><i>N</i>/10 <i>Potassium Bichromate</i>&mdash;Dissolve 4.903 g. of C. P. potassium
+bichromate in water and make the volume up to one liter at the
+temperature at which titrations are to be made.</p>
+
+<p>The Committee calls attention to the fact that occasionally potassium
+bichromate is found containing sodium bichromate, although this is of
+rare occurrence. If the analyst suspects that he is dealing with an
+impure potassium bichromate, the purity can be ascertained by titration
+against re-sublimed iodine. However, this is unnecessary in the great
+majority of cases.</p>
+
+<p><i>Standardization of the Sodium Thiosulfate Solution</i>&mdash;Place 40 cc. of
+the potassium bichromate solution, to which has been added 10 cc. of the
+solution of potassium iodide, in a glass-stoppered flask. Add to this 5
+cc. of strong hydro-chloric acid. Dilute with 100 cc. of water, and
+allow the <i>N</i>/10 sodium thiosulfate to flow slowly into the flask until
+the yellow color of the liquid has almost disappeared. Add a few drops
+of the starch paste, and with constant shaking continue to add the
+<i>N</i>/10 sodium thiosulfate solution until the blue color just disappears.</p>
+
+<p><span class="smcap">Determination</span>&mdash;Weigh accurately from 0.10 to 0.50 g. (depending on the
+iodine number) of the melted and filtered sample into a clean, dry,
+16-oz. glass-stoppered bottle containing 15-20 cc. of carbon
+tetrachloride or chloroform. Add 25 cc. of iodine solution from a
+pipette, allowing to drain for a definite time. The excess of iodine
+should be from 50 per cent to 60 per cent of the amount added, that is,
+from 100 per cent to 150 per cent of the amount absorbed. Moisten the
+stopper with a 15 per cent potassium iodide solution to prevent loss of
+iodine or chlorine but guard against an amount sufficient to run down
+inside the bottle. Let<span class='pagenum'><a name="Page_180" id="Page_180">[Pg 180]</a></span> the bottle stand in a dark place for 1/2 hr. at
+a uniform temperature. At the end of that time add 20 cc. of 15 per cent
+potassium iodide solution and 100 cc. of distilled water. Titrate the
+iodine with <i>N</i>/10 sodium thiosulfate solution which is added gradually,
+with constant shaking, until the yellow color of the solution has almost
+disappeared. Add a few drops of starch paste and continue titration
+until the blue color has entirely disappeared. Toward the end of the
+reaction stopper the bottle and shake violently so that any iodine
+remaining in solution in the tetrachloride or chloroform may be taken up
+by the potassium iodide solution. Conduct two determinations on blanks
+which must be run in the same manner as the sample except that no fat is
+used in the blanks. Slight variations in temperature quite appreciably
+affect the titer of the iodine solution, as acetic acid has a high
+coefficient of expansion. It is, therefore, essential that the blanks
+and determinations on the sample be made at the same time. The number of
+cc. of standard thiosulfate solution required by the blank, less the
+amount used in the determination, gives the thiosulfate equivalent of
+the iodine absorbed by the amount of sample used in the determination.
+Calculate to centigrams of iodine absorbed by 1 g. of sample (= per cent
+iodine absorbed).</p>
+
+<p><span class="smcap">Determination, Tung Oil</span>&mdash;Tung oil shows an erratic behavior with most
+iodine reagents and this is particularly noticeable in the case of the
+Hanus reagent which is entirely unsuitable for determining the iodine
+number of this oil since extremely high and irregular results are
+obtained. The H&uuml;bl solution shows a progressive absorption up to 24 hrs.
+and probably for a longer time but the period required is entirely too
+long for a chemical determination. The Wijs solution gives good results
+if the following precautions are observed:</p>
+
+<p>Weigh out 0.15 &plusmn; 0.05 g., use an excess of 55 &plusmn; 3 per<span class='pagenum'><a name="Page_181" id="Page_181">[Pg 181]</a></span> cent Wijs
+solution. Conduct the absorption at a temperature of 20-25&deg; C. for 1 hr.
+In other respects follow the instructions detailed above.</p>
+
+
+<h4>SAPONIFICATION NUMBER (KOETTSTORFER NUMBER).</h4>
+
+<p><span class="smcap">Preparation of Reagents.</span> <i>N/2 Hydrochloric Acid</i>&mdash;Carefully
+standardized.</p>
+
+<p><i>Alcoholic Potassium Hydroxide Solution</i>&mdash;Dissolve 40 g. of pure
+potassium hydroxide in one liter of 95 per cent redistilled alcohol (by
+volume). The alcohol should be redistilled from potassium hydroxide over
+which it has been standing for some time, or with which it has been
+boiled for some time, using a reflux condenser. The solution must be
+clear and the potassium hydroxide free from carbonates.</p>
+
+<p><span class="smcap">Determination</span>&mdash;Weigh accurate about 5 g. of the filtered sample into a
+250 to 300 cc. Erlenmeyer flask. Pipette 50 cc. of the alcoholic
+potassium hydroxide solution into the flask, allowing the pipette to
+drain for a definite time. Connect the flask with an air condenser and
+boil until the fat is completely saponified (about 30 minutes). Cool and
+titrate with the <i>N</i>/2 hydrochloric acid, using phenolphthalein as an
+indicator. Calculate the Koettstorfer number (mg. of potassium hydroxide
+required to saponify 1 g. of fat). Conduct 2 or 3 blank determinations,
+using the same pipette and draining for the same length of time as
+above.</p>
+
+
+<h4>MELTING POINT.</h4>
+
+<p><span class="smcap">Apparatus</span>&mdash;<i>Capillary tubes</i> made from 5 mm. inside diameter thin-walled
+glass tubing drawn out to 1 mm. inside diameter. Length of capillary
+part of tubes to be about 5 cm. Length of tube over all 8 cm.</p>
+
+<p><i>Standard thermometer</i> graduated in tenths of a degree.</p>
+
+<p><i>600 cc. beaker.</i></p>
+
+<p><span class="smcap">Determination</span>&mdash;The sample should be clear when melted<span class='pagenum'><a name="Page_182" id="Page_182">[Pg 182]</a></span> and entirely free
+from moisture, or incorrect results will be obtained.</p>
+
+<p>Melt and thoroughly mix the sample. Dip three of the capillary tubes
+above described in the oil so that the fat in the tube stands about 1
+cm. in height. Now fuse the capillary end carefully by means of a small
+blast flame and allow to cool. These tubes are placed in a refrigerator
+over night at a temperature of from 40 to 50&deg; F. They are then fastened
+by means of a rubber band or other suitable means to the bulb of a
+thermometer graduated in tenths of a degree. The thermometer is
+suspended in a beaker of water (which is agitated by air or other
+suitable means) so that the bottom of the bulb of the thermometer is
+immersed to a depth of about 3 cm. The temperature of the water is
+increased gradually at the rate of about 1&deg; per minute.</p>
+
+<p>The point at which the sample becomes opalescent is first noted and the
+heating continued until the contents of the tube becomes uniformly
+transparent. The latter temperature is reported as the melting point.</p>
+
+<p>Before finally melting to a perfectly clear fluid, the sample becomes
+opalescent and usually appears clear at the top, bottom, and sides
+before becoming clear at the center. The heating is continued until the
+contents of the tube become uniformly clear and transparent. This
+temperature is reported as the melting point.<a name="FNanchor_33_33" id="FNanchor_33_33"></a><a href="#Footnote_33_33" class="fnanchor">[33]</a> It is usually only a
+fraction of a degree above the opalescent point noted. The thermometer
+should be read to the nearest 1/2&deg; C., and in addition this temperature
+may be reported to the nearest degree Fahrenheit if desired.</p>
+
+
+<h4>CLOUD TEST.</h4>
+
+<p><span class="smcap">Precautions</span>&mdash;(1) The oil must be perfectly dry, because<span class='pagenum'><a name="Page_183" id="Page_183">[Pg 183]</a></span> the presence of
+moisture will produce a turbidity before the clouding point is reached.</p>
+
+<p>(2) The oil must be heated to 150&deg; C. over a free flame, immediately
+before making the test.</p>
+
+<p>(3) There must not be too much discrepancy between the temperature of
+the bath and the clouding point of the oil. An oil that will cloud at
+the temperature of hydrant water should be tested in a bath of that
+temperature. An oil that will cloud in a mixture of ice and water should
+be tested in such a bath. An oil that will not cloud in a bath of ice
+and water must be tested in a bath of salt, ice, and water.</p>
+
+<p><span class="smcap">Determination</span>&mdash;The oil is heated in a porcelain casserole over a free
+flame to 150&deg; C., stirring with the thermometer. As soon as it can be
+done with safety, the oil is transferred to a 4 oz. oil bottle, which
+must be perfectly dry. One and one-half ounces of the oil are sufficient
+for the test. A dry centigrade thermometer is placed in the oil, and the
+bottle is then cooled by immersion in a suitable bath. The oil is
+constantly stirred with the thermometer, taking care not to remove the
+thermometer from the oil at any time during the test, so as to avoid
+stirring air bubbles into the oil. The bottle is frequently removed from
+the bath for a few moments. The oil must not be allowed to chill on the
+sides and bottom of the bottle. This is effected by constant and
+vigorous stirring with the thermometer. As soon as the first permanent
+cloud shows in the body of the oil, the temperature at which this cloud
+occurs is noted.</p>
+
+<p>With care, results concordant to within 1/2&deg; C. can be obtained by this
+method. A Fahrenheit thermometer is sometimes used because it has become
+customary to report results in degrees Fahrenheit.</p>
+
+<p>The oil must be tested within a short time after heating to 150&deg; C. and
+a re-test must always be preceded by reheating to that temperature. The
+cloud point should be<span class='pagenum'><a name="Page_184" id="Page_184">[Pg 184]</a></span> approached as quickly as possible, yet not so
+fast that the oil is frozen on the sides or bottom of the bottle before
+the cloud test is reached.</p>
+
+
+<h3>Notes on the Above Methods.</h3>
+
+
+<h4>SAMPLING.</h4>
+
+<p>The standard size of sample adopted by the committee is at least 3 lbs.
+in weight. The committee realizes that this amount is larger than any
+samples usually furnished even when representing shipments of from
+20,000 to 60,000 lbs. but it believes that the requirement of a larger
+sample is desirable and will work toward uniform and more concordant
+results in analysis. It will probably continue to be the custom of the
+trade to submit smaller buyers' samples than required by the committee,
+but these are to be considered only as samples for inspection and not
+for analysis. The standard analytical sample must consist of 3 lbs. or
+more.</p>
+
+<p>The reasons for keeping samples in a dark, cool place are obvious. This
+is to prevent any increase in rancidity and any undue increase in free
+fatty acids. In the case of many fats the committee has found in its
+co-operative analytical work that free acid tends to increase very
+rapidly. This tendency is minimized by low temperatures.</p>
+
+
+<h4>MOISTURE AND VOLATILE MATTER.</h4>
+
+<p>After careful consideration the committee has decided that moisture is
+best determined in a vacuum oven of the design which accompanies the
+above report. Numerous results on check samples have confirmed the
+committee's conclusions. The oven recommended by the committee is
+constructed on the basis of well-known principles and it is hoped that
+this type will be adopted generally by chemists who are called upon to
+analyze fats and oils. The experiments of the committee indicate that it
+is a most difficult matter to design a vacuum oven which will produce
+uniform temperatures<span class='pagenum'><a name="Page_185" id="Page_185">[Pg 185]</a></span> throughout; and one of the principal ideas in the
+design adopted is uniformity of temperature over the entire single
+shelf. This idea has not quite been realized in practice but,
+nevertheless, the present design approaches much closer to the ideal
+than other vacuum ovens commonly used. In the drawing the essential
+dimensions are those between the heating units and the shelf and the
+length and breadth of the outer casting. The standard Fat Analysis
+Committee Oven (F. A. C. Oven) can be furnished by Messrs. E. H. Sargent
+&amp; Company, 125 West Lake street, Chicago.</p>
+
+<p>The committee realizes that for routine work a quicker method is
+desirable and has added one such method and has also stated the
+conditions under which comparable results can be obtained by means of
+the ordinary well-ventilated air oven held at 105 to 110&deg; C. However, in
+accordance with a fundamental principle adopted by the committee at its
+first meeting, only one standard method is adopted and declared official
+for each determination.</p>
+
+<p>The committee realizes that in the case of all methods for determining
+moisture by means of loss on heating there may be a loss due to volatile
+matter (especially fatty acids) other than water. The title of the
+determination <span class="smcap">moisture and volatile matter</span> indicates this idea, but any
+considerable error from this source may occur only in the case of high
+acid fats and oils and particularly those containing lower fatty acids
+such as coconut and palm kernel oil. In the case of extracted greases
+which have not been properly purified, some of the solvent may also be
+included in the moisture and volatile matter determination, but inasmuch
+as the solvent, usually a petroleum product, can only be considered as
+foreign matter, for commercial purposes, it is entirely proper to
+include it with the moisture.</p>
+
+<p>The committee has also considered the various distillation methods for
+the determination of moisture in fats and oils,<span class='pagenum'><a name="Page_186" id="Page_186">[Pg 186]</a></span> but since according to
+the fundamental principles which it was endeavoring to follow it could
+only standardize one method, it was decided that the most desirable one
+on the whole was the vacuum-oven method as given. There are cases
+wherein a chemist may find it desirable to check a moisture
+determination or investigate the moisture content of a fat or oil
+further by means of one of the distillation methods.</p>
+
+<p>However, in co-operative work the distillation method in various types
+of apparatus has not yielded satisfactory results. The difficulties
+appear to be connected with a proper choice of solvent and particularly
+with the tendency of drops of water to adhere to various parts of the
+glass apparatus instead of passing on to the measuring device. When
+working on coconut oil containing a high percentage of free fatty acids,
+concordant results could not be obtained by the various members of the
+committee when working with identical samples, solvents and apparatus.</p>
+
+<p>On the other hand, the committee found by individual work, co-operative
+work and collaborative work by several members of the committee in one
+laboratory, that the old, well-known direct heating method (which the
+committee has designated the hot plate method) yielded very satisfactory
+results on all sorts of fats and oils including emulsions such as butter
+and oleomargarine and even on coconut oil samples containing 15 to 20
+per cent free fatty acids and 5 to 6 per cent of moisture.
+Unfortunately, this method depends altogether on the operator's skill
+and while the method may be taught to any person whether a chemist or
+not so that he can obtain excellent results with it, it is difficult to
+give a sufficiently, complete description of it so that any chemist
+anywhere after reading the description could follow it successfully. The
+method is undoubtedly worthy of much confidence in careful hands. It is
+quick, accurate and reliable.<span class='pagenum'><a name="Page_187" id="Page_187">[Pg 187]</a></span> It is probably the best single method for
+the determination of moisture in all sorts of samples for routine
+laboratory work. On account of this fact the committee desires to
+announce its willingness to instruct any person in the proper use of the
+method who desires to become acquainted with it and who will visit any
+committee member's laboratory.</p>
+
+
+<h4>INSOLUBLE IMPURITIES.</h4>
+
+<p>This determination, the title for which was adopted after careful
+consideration, determines the impurities which have generally been known
+as dirt, suspended matter, suspended solids, foreign solids, foreign
+matter, etc., in the past. The first solvent recommended by the
+committee is hot kerosene to be followed by petroleum ether kept at
+ordinary room temperature. Petroleum ether, cold or only slightly warm,
+is not a good fat and metallic soap solvent, whereas hot kerosene
+dissolves these substances readily, and for this reason the committee
+has recommended the double solvent method so as to exclude metallic
+soaps which are determined below as soluble mineral matter.</p>
+
+
+<h4>SOLUBLE MINERAL MATTER.</h4>
+
+<p>Soluble mineral matter represents mineral matter combined with fatty
+acids in the form of soaps in solution in the fat or oil. Formerly, this
+mineral matter was often determined in combination by weighing the
+separated metallic soap or by weighing it in conjunction with the
+insoluble impurities. Since the soaps present consist mostly of lime
+soap, it has been customary to calculate the lime present therein by
+taking 0.1 the weight of the total metallic soaps. The standard method
+as given above is direct and involves no calculation. The routine method
+given in the note has been placed among the methods for the reason that
+it is used in some laboratories, but has not been adopted as a standard
+method in view of the fact that the committee has<span class='pagenum'><a name="Page_188" id="Page_188">[Pg 188]</a></span> made it a rule to
+adopt only one standard method. It should be pointed out, however, that
+the method cannot be considered accurate for the reason that insoluble
+impurities may vary from sample to sample to a considerable extent and
+the error due to the presence of large particles of insoluble impurities
+is thus transferred to the soluble mineral matter. The committee has
+found one type of grease (naphtha bone grease) which shows most unusual
+characteristics. The type sample contains 4.3 per cent soluble mineral
+matter by the committee method which would be equivalent to 43.0 per
+cent free fatty acid. The kerosene and gasoline filtrate was
+particularly clear, nevertheless the ash was found to contain 36.43 per
+cent P<sub>2</sub>O<sub>5</sub> equivalent to 79.60 per cent of Ca<sub>3</sub>(PO<sub>4</sub>)<sub>2</sub> and
+9.63 per cent of Fe<sub>2</sub>O<sub>3</sub>. The method, therefore, determines the
+soluble mineral matter in this case satisfactorily but the factor 10 is
+not applicable for calculating the fatty acids combined therewith. It is
+necessary, therefore, in order to determine the fatty acids combined
+with soluble mineral matter in the original sample to determine the
+actual bases in the soluble mineral matter as obtained by ashing the
+kerosene and gasoline filtrate. To the bases so determined the factor 10
+can then be applied.</p>
+
+
+<h4>FREE FATTY ACID.</h4>
+
+<p>The fatty acid method adopted is sufficiently accurate for commercial
+purposes. In many routine laboratories the fat or oil is measured and
+not weighed, but the committee recommends weighing the sample in all
+cases. For scientific purposes the result is often expressed as "acid
+number," meaning the number of milligrams of KOH required to neutralize
+the free acids in one gram of fat, but the commercial practice has been,
+and is, to express the fatty acids as oleic acid or in the case of palm
+oil, as palmitic acid, in some instances. The committee sees no
+objection to the<span class='pagenum'><a name="Page_189" id="Page_189">[Pg 189]</a></span> continuation of this custom so long as the analytical
+report clearly indicates how the free acid is expressed. For a more
+exact expression of the free acid in a given fat, the committee
+recommends that the ratio of acid number to saponification number be
+used. This method of expressing results is subject to error when
+unsaponifiable fatty matter is present, since the result expresses the
+ratio of free fatty acid to total saponifiable fatty matter present.</p>
+
+
+<h4>TITER.</h4>
+
+<p>At the present time the prices of glycerol and caustic potash are
+abnormally high, but the committee has considered that the methods
+adopted are for normal times and normal prices. For routine work during
+the period of high prices the following method may be used for preparing
+the fatty acids and is recommended by the committee:</p>
+
+<p>Fifty grams of fat are saponified with 60 cc. of a solution of 2 parts
+of methyl alcohol to 1 of 50 per cent NaOH. The soap is dried,
+pulverized and dissolved in 1000 cc. of water in a porcelain dish and
+then decomposed with 25 cc. of 75 per cent sulphuric acid. The fatty
+acids are boiled until clear oil is formed and then collected and
+settled in a 150-cc. beaker and filtered into a 50-cc. beaker. They are
+then heated to 130&deg; C. as rapidly as possible with stirring, and
+transferred, after they have cooled somewhat, to the usual 1-in. by
+4-in. titer tube.</p>
+
+<p>The method of taking the titer, including handling the thermometer, to
+be followed is the same as that described in the standard method. Even
+at present high prices many laboratories are using the glycerol-caustic
+potash method for preparing the fatty acids, figuring that the saving of
+time more than compensates for the extra cost of the reagents. Caustic
+soda cannot be substituted for caustic potash in the glycerol method.<span class='pagenum'><a name="Page_190" id="Page_190">[Pg 190]</a></span></p>
+
+<h4>UNSAPONIFIABLE MATTER.</h4>
+
+<p>The committee has considered unsaponifiable matter to include those
+substances frequently found dissolved in fats and oils which are not
+saponified by the caustic alkalies and which at the same time are
+soluble in the ordinary fat solvents. The term includes such substances
+as the higher alcohols, such as cholesterol which is found in animal
+fats, phytosterol found in some vegetable fats, paraffin and petroleum
+oils, etc. <span class="smcap">Unsaponifiable matter</span> should not be confused in the lay mind
+with <span class="smcap">insoluble impurities or soluble mineral matter.</span></p>
+
+<p>The method adopted by the committee has been selected only after the
+most careful consideration of other methods, such as the dry extraction
+method and the wet method making use of the separatory funnel. At first
+consideration the dry extraction process would seem to offer the best
+basis for an unsaponifiable matter method, but in practice it has been
+found absolutely impossible for different analysts to obtain agreeing
+results when using any of the dry extraction methods proposed.
+Therefore, this method had to be abandoned after numerous trials,
+although several members of the committee strongly favored it in the
+beginning.</p>
+
+<p><span class="smcap">Iodine Number</span>&mdash;The iodine number adopted by the committee is that
+determined by the well-known Wijs method. This method was adopted after
+careful comparison with the Hanus and H&uuml;bl methods. The H&uuml;bl method was
+eliminated from consideration almost at the beginning of the committee's
+work for the reason that the time required for complete absorption of
+the iodine is unnecessarily long and, in fact, even after absorption has
+gone on over night, it is apparently not complete. In the case of the
+Hanus and Wijs methods complete absorption takes place in from 15
+minutes to an hour, depending on conditions. Formerly, many chemists
+thought the Hanus solution rather easier to prepare<span class='pagenum'><a name="Page_191" id="Page_191">[Pg 191]</a></span> than the Wijs
+solution, but the experience of the committee was that the Wijs solution
+was no more difficult to prepare than the Hanus. Furthermore, absorption
+of iodine from the Wijs solution appeared to take place with greater
+promptness and certainty than from the Hanus and was complete in a
+shorter time. Results by the Wijs method were also in better agreement
+in the case of oils showing high iodine absorption than with the Hanus
+solution and showed a slightly higher iodine absorption for the same
+length of time. However, the difference was not great. The committee
+investigated the question of substitution since it has been suggested
+that in case of the Wijs solution substitution of iodine in the organic
+molecule might occur, and found no evidence of this in the time required
+for the determination, namely, 1/2 hr., or even for a somewhat longer
+period. One member of the committee felt that it was not desirable to
+introduce the Wijs method into these standard methods since the Hanus
+method was already standardized by the Association of Official
+Agricultural Chemists, but the committee felt that it must follow the
+principle established at the commencement of its work, namely, that of
+adopting the method which appeared to be the best from all standpoints,
+taking into consideration accuracy, convenience, simplicity, time,
+expense, etc., without allowing precedent to have the deciding vote.</p>
+
+<p><span class="smcap">Iodine Number, Tung Oil</span>&mdash;The committee has made an extensive study of
+the application of the Wijs method to the determination of iodine value
+in the case of tung oil with the result that it recommends the method
+for this oil but has thought it desirable to limit the conditions under
+which the determination is conducted rather narrowly, although
+reasonably good results are obtained by the committee method without
+making use of the special limitations.</p>
+
+<p>The co-operative work of the committee and the special<span class='pagenum'><a name="Page_192" id="Page_192">[Pg 192]</a></span> investigations
+conducted by individual members bring out the following points:</p>
+
+<p><i>Influence of Temperature</i>&mdash;From 16&deg; C. to 30&deg; C. there is a moderate
+increase in the absorption, but above 30&deg; the increase is rather rapid
+so that it was thought best to limit the temperature in the case of tung
+oil to 20&deg; to 25&deg; C.</p>
+
+<p><i>Influence of Time</i>&mdash;The absorption increases with the time but
+apparently complete absorption, so far as unsaturated bonds are
+concerned, occurs well within one hour's time. Consequently, one hour
+was set as the practical limit.</p>
+
+<p><i>Influence of Excess</i>&mdash;The excess of iodine solution also tends to
+increase the iodine number, hence the Committee thought it necessary to
+limit the excess rather rigidly to 55 &plusmn; 3 per cent, although with
+greater latitude results were reasonably good.</p>
+
+<p><i>Influence of Age of Solution</i>&mdash;Old solutions tend to give low results
+although up to 2 mo. no great differences were observed. Nevertheless,
+it was thought best to limit the age of the solution to 30 days&mdash;long
+enough for all practical purposes.</p>
+
+<p><i>Amount of Sample</i>&mdash;As a practical amount of sample to be weighed out
+the Committee decided on 0.15 g. with a tolerance of 0.05 g. in either
+direction according to preference. In other words, the amount of sample
+to be taken for the determination to be from 0.1 to 0.2 g. in the
+discretion of the analyst.</p>
+
+<p>The Committee's study of the H&uuml;bl method which has been adopted by the
+Society for Testing Materials in the case of tung oil indicates that
+this method when applied to tung oil is subject to the same influences
+as the Wijs method and it has the additional very serious disadvantage
+of requiring a long period of time for absorption which cannot be
+considered reasonable for a modern analytical method. When using the
+H&uuml;bl solution, the absorption is<span class='pagenum'><a name="Page_193" id="Page_193">[Pg 193]</a></span> not complete in the case of tung oil
+at 3, 7, 18 or even 24 hrs.</p>
+
+<p>The Hanus method in the case of tung oil gives very high and erratic
+results, as high as 180 to 240 in ordinary cases for an oil whose true
+iodine number is about 165.</p>
+
+
+<h4>MELTING POINT.</h4>
+
+<p>A melting point is the temperature at which a solid substance assumes
+the liquid condition. If the solid is a pure substance in the
+crystalline condition the melting point is sharp and well defined for
+any given pressure. With increased pressure the melting point is lowered
+or raised, depending on whether the substance contracts or expands in
+melting. The lowering or raising of the melting point with pressure is
+very slight and ordinarily is not taken into consideration.
+Melting-point determinations are commonly carried out under ordinary
+atmospheric pressures without correction. The general effect of soluble
+impurities is to lower the melting point, and this holds true whether
+the impurity has a higher or lower melting point than the pure substance
+(solvent). Thus if a small amount of stearic acid be added to liquid
+palmitic acid and the solution frozen, the melting point of this solid
+will be lower than that of palmitic acid. Likewise the melting point of
+stearic acid is lowered by the addition of a small amount of palmitic
+acid. A eutectic mixture results when two components solidify
+simultaneously at a definite temperature. Such a mixture has a constant
+melting point and because of this and also because both solid and liquid
+phases have the same composition, eutectic mixtures were formerly looked
+upon as compounds. The phenomenon of double melting points has been
+observed in the case of a number of glycerides. Such a glyceride when
+placed in the usual capillary tube and subjected to increasing
+temperature quickly resolidifies only<span class='pagenum'><a name="Page_194" id="Page_194">[Pg 194]</a></span> to melt again and remain melted
+at a still higher temperature. This phenomenon has not yet been
+sufficiently investigated to afford a satisfactory explanation.</p>
+
+<p>Non-crystalline substances such as glass, sealing wax and various other
+waxes and wax mixtures, and most colloidal substances do not exhibit a
+sharp melting point, but under the application of heat first soften very
+gradually and at a considerably higher temperature melt sufficiently to
+flow. This phenomenon of melting through a long range of temperature may
+be due to the amorphous nature of the substance or to the fact that it
+consists of a very large number of components of many different melting
+points.</p>
+
+<p>The fats and oils of natural origin, that is, the animal and vegetable
+fats and oils, consist of mixtures of glycerides and, generally
+speaking, of a considerable number of such components. These components
+are crystalline and when separated in the pure state have definite
+melting points, although some exhibit the phenomenon of double melting
+point. For the most part the naturally occurring glycerides are mixed
+glycerides. In the natural fats and oils there are present also certain
+higher alcohols, of which cholesterol is characteristic of the animal
+fats and oils and phytosterol of many of the vegetable fats and oils. In
+addition to the crystalline glycerides and the higher alcohols present
+in neutral fats, there are in fats of lower grade, fatty acids, which
+are crystalline, and also various non-crystalline impurities of an
+unsaponifiable nature, and the presence of these impurities tends to
+lower the melting point. They also tend to induce undercooling and when
+the liquid fat or oil is being chilled for purposes of solidification or
+in determination of titer.</p>
+
+<p>The presence of water, especially when this is thoroughly mixed or
+emulsified with a fat or oil, also influences the melting point to a
+marked extent, causing the mixture to<span class='pagenum'><a name="Page_195" id="Page_195">[Pg 195]</a></span> melt through a longer range of
+temperatures than would be the case if the water were absent. This is
+particularly true of emulsified fats and oils, such as butter and
+oleomargarine, both of which contain, besides water, the solids
+naturally present in milk or cream and including casein, milk sugar, and
+salts. The melting-point method recommended by the Committee is not
+applicable to such emulsions or other watery mixtures and the Committee
+has found it impossible to devise an accurate method for making
+softening-point or melting-point determinations on products of this
+nature. Not only the amount of water present but also the fineness of
+its particles, that is, its state of subdivision and distribution, in a
+fat or oil influences the softening point or melting point and causes it
+to vary widely in different samples.</p>
+
+<p>As a consequence of the foregoing facts, natural fats and oils do not
+exhibit a definite melting point, composed as they are of mixtures of
+various crystalline glycerides, higher alcohols, fatty acids, and
+non-crystalline substances. Therefore, the term melting point when
+applied to them requires further definition. They exhibit first a lower
+melting point (the melting point of the lowest melting component) or
+what might be called the softening point and following this the fat
+softens through a shorter or longer range of temperature to the final
+melting point at which temperature the fat is entirely liquid. This is
+the melting point determined by the Committee's melting-point method.
+The range between the softening point and the final melting point varies
+greatly with the different fats and oils depending on their chemical
+components, the water associated with them, emulsification, etc. In the
+case of coconut oil the range between softening point and final melting
+point is rather short; in the case of butter, long. Various methods have
+been devised to determine the so-called melting point of fats and oils.
+Most of these methods, however, determine, not<span class='pagenum'><a name="Page_196" id="Page_196">[Pg 196]</a></span> the melting point, but
+the softening point or the flow point of the fat and the great
+difficulty has been in the past to devise a method which would determine
+even this point with reasonable accuracy and so that results could be
+easily duplicated. It has been the aim of the Committee to devise a
+simple method for the determination of the melting point of fats and
+oils, but it should be understood that the term melting point in the
+scientific sense is not applicable to natural fats and oils.</p>
+
+<div class="footnotes"><h3>FOOTNOTES:</h3>
+
+<div class="footnote"><p><a name="Footnote_22_22" id="Footnote_22_22"></a><a href="#FNanchor_22_22"><span class="label">[22]</span></a> Approved by the Supervisory Committee on Standard Methods
+of Analysis of the American Chemical Society.</p></div>
+
+<div class="footnote"><p><a name="Footnote_23_23" id="Footnote_23_23"></a><a href="#FNanchor_23_23"><span class="label">[23]</span></a> Live steam must not be turned into tank cars or coils
+before samples are drawn, since there is no certain way of telling when
+coils are free from leaks.</p></div>
+
+<div class="footnote"><p><a name="Footnote_24_24" id="Footnote_24_24"></a><a href="#FNanchor_24_24"><span class="label">[24]</span></a> If there is water present under the solid material this
+must be noted and estimated separately.</p></div>
+
+<div class="footnote"><p><a name="Footnote_25_25" id="Footnote_25_25"></a><a href="#FNanchor_25_25"><span class="label">[25]</span></a> Boiling point of water at reduced pressures.
+</p>
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Pressure Mm. Hg.</td><td align='left'>Boiling Point to 1&deg; C.</td><td align='left'>Boiling Point +15&deg; C.</td><td align='left'>Boiling Point +20&deg; C.</td></tr>
+<tr><td align='right'>100</td><td align='right'>52&deg; C.</td><td align='right'>67&deg; C.</td><td align='right'>72&deg; C.</td></tr>
+<tr><td align='right'>90</td><td align='right'>50</td><td align='right'>65</td><td align='right'>70</td></tr>
+<tr><td align='right'>80</td><td align='right'>47</td><td align='right'>62</td><td align='right'>67</td></tr>
+<tr><td align='right'>70</td><td align='right'>45</td><td align='right'>60</td><td align='right'>65</td></tr>
+<tr><td align='right'>60</td><td align='right'>42</td><td align='right'>57</td><td align='right'>62</td></tr>
+<tr><td align='right'>50</td><td align='right'>38</td><td align='right'>53</td><td align='right'>58</td></tr>
+<tr><td align='right'>40</td><td align='right'>34</td><td align='right'>49</td><td align='right'>54</td></tr>
+</table></div>
+</div>
+
+<div class="footnote"><p><a name="Footnote_26_26" id="Footnote_26_26"></a><a href="#FNanchor_26_26"><span class="label">[26]</span></a> Results comparable to those of the Standard Method may be
+obtained on most fats and oils by drying 5-g. portions of the sample,
+prepared and weighed as above, to constant weight in a well-constructed
+and well-ventilated air oven held uniformly at a temperature of 105&deg; to
+110&deg; C. The thermometer bulb should be close to the sample. The
+definition of constant weight is the same as for the Standard Method.</p></div>
+
+<div class="footnote"><p><a name="Footnote_27_27" id="Footnote_27_27"></a><a href="#FNanchor_27_27"><span class="label">[27]</span></a> The following method is suggested by the Committee for
+routine control work: Weigh out 5- to 25-g. portions of prepared sample
+into a glass or aluminum (<i>Caution</i>: Aluminum soap may be formed) beaker
+or casserole and heat on a heavy asbestos board over burner or hot
+plate, taking care that the temperature of the sample does not go above
+130&deg; C. at any time. During the heating rotate the vessel gently on the
+board by hand to avoid sputtering or too rapid evolution of moisture.
+The proper length of time of heating is judged by absence of rising
+bubbles of steam, by the absence of foam or by other signs known to the
+operator. Avoid overheating of sample as indicated by smoking or
+darkening. Cool in desiccator and weigh.
+</p><p>
+By co-operative work in several laboratories, the Committee has
+demonstrated that this method can be used and satisfactory results
+obtained on coconut oil even when a considerable percentage of free
+fatty acids is present, and the method is recommended for this purpose.
+Unfortunately on account of the very great personal factor involved, the
+Committee cannot establish this method as a preferred method.
+Nevertheless, after an operator has learned the technique of the method,
+it gives perfectly satisfactory results for ordinary oils and fats,
+butter, oleomargarine and coconut oil, and deserves more recognition
+than it has heretofore received.</p></div>
+
+<div class="footnote"><p><a name="Footnote_28_28" id="Footnote_28_28"></a><a href="#FNanchor_28_28"><span class="label">[28]</span></a> For routine control work, filter paper is sometimes more
+convenient than the prepared Gooch crucible, but must be very carefully
+washed, especially around the rim, to remove the last traces of fat.</p></div>
+
+<div class="footnote"><p><a name="Footnote_29_29" id="Footnote_29_29"></a><a href="#FNanchor_29_29"><span class="label">[29]</span></a> For routine work, an ash may be run on the original fat,
+and the soluble mineral matter obtained by deducting the ash on the
+insoluble impurities from this. In this case the Gooch crucible should
+be prepared with an ignited asbestos mat so that the impurities may be
+ashed directly after being weighed. In all cases ignition should be to
+constant weight so as to insure complete decomposition of carbonates.</p></div>
+
+<div class="footnote"><p><a name="Footnote_30_30" id="Footnote_30_30"></a><a href="#FNanchor_30_30"><span class="label">[30]</span></a> See note on Soluble Mineral Matter following these
+methods. When the ash contains phosphates the factor 10 cannot be
+applied, but the bases consisting of calcium oxide, etc., must be
+determined, and the factor 10 applied to them.</p></div>
+
+<div class="footnote"><p><a name="Footnote_31_31" id="Footnote_31_31"></a><a href="#FNanchor_31_31"><span class="label">[31]</span></a> For routine work methyl or denatured ethyl alcohol of
+approximately 95 per cent strength may be used. With these reagents the
+end-point is not sharp.</p></div>
+
+<div class="footnote"><p><a name="Footnote_32_32" id="Footnote_32_32"></a><a href="#FNanchor_32_32"><span class="label">[32]</span></a> P. C. McIlhiney, <i>J. Am. Chem. Soc.</i>, 29 (1917), 1222,
+gives the following details for the preparation of the iodine
+monochloride solution:
+</p><p>
+The preparation of the iodine monochloride solution presents no great
+difficulty, but it must be done with care and accuracy in order to
+obtain satisfactory results. There must be in the solution no sensible
+excess either of iodine or more particularly of chlorine, over that
+required to form the monochloride. This condition is most satisfactorily
+attained by dissolving in the whole of the acetic acid to be used the
+requisite quantity of iodine, using a gentle heat to assist the
+solution, if it is found necessary, setting aside a small portion of
+this solution, while pure and dry chlorine is passed into the remainder
+until the halogen content of the whole solution is doubled. Ordinarily
+it will be found that by passing the chlorine into the main part of the
+solution until the characteristic color of free iodine has just been
+discharged there will be a slight excess of chlorine which is corrected
+by the addition of the requisite amount of the unchlorinated portion
+until all free chlorine has been destroyed. A slight excess of iodine
+does little or no harm, but excess of chlorine must be avoided.</p></div>
+
+<div class="footnote"><p><a name="Footnote_33_33" id="Footnote_33_33"></a><a href="#FNanchor_33_33"><span class="label">[33]</span></a> The melting point of oils may be determined in general
+according to the above procedure, taking into consideration the lower
+temperature required.</p></div>
+</div>
+
+
+<hr style="width: 65%;" /><p><span class='pagenum'><a name="Page_198" id="Page_198">[Pg 198]</a></span></p>
+<h2>PLANT AND MACHINERY</h2>
+
+<h3>Illustrations of machinery and layouts of the plant of a modern
+soap-making establishment.</h3>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_199" id="Page_199">[Pg 199]</a></span></p>
+
+<div class="figcenter" style="width: 384px;">
+<img src="images/p199.jpg" width="384" height="640" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_200" id="Page_200">[Pg 200]</a></span></p>
+
+<div class="figcenter" style="width: 640px;">
+<img src="images/p200.jpg" width="640" height="451" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_201" id="Page_201">[Pg 201]</a></span></p>
+
+<div class="figcenter" style="width: 480px;">
+<img src="images/p201.jpg" width="480" height="638" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_202" id="Page_202">[Pg 202]</a></span></p>
+
+<div class="figcenter" style="width: 458px;">
+<img src="images/p202.jpg" width="458" height="640" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_203" id="Page_203">[Pg 203]</a></span></p>
+
+<div class="figcenter" style="width: 480px;">
+<img src="images/p203.jpg" width="480" height="597" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_204" id="Page_204">[Pg 204]</a></span></p>
+
+<div class="figcenter" style="width: 480px;">
+<img src="images/p204.jpg" width="480" height="636" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_205" id="Page_205">[Pg 205]</a></span></p>
+
+<div class="figcenter" style="width: 468px;">
+<img src="images/p205.jpg" width="468" height="640" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_206" id="Page_206">[Pg 206]</a></span></p>
+
+<div class="figcenter" style="width: 480px;">
+<img src="images/p206.jpg" width="480" height="599" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_207" id="Page_207">[Pg 207]</a></span></p>
+
+<div class="figcenter" style="width: 614px;">
+<img src="images/p207.jpg" width="614" height="480" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_208" id="Page_208">[Pg 208]</a></span></p>
+
+<div class="figcenter" style="width: 480px;">
+<img src="images/p208.jpg" width="480" height="619" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_209" id="Page_209">[Pg 209]</a></span></p>
+
+<div class="figcenter" style="width: 480px;">
+<img src="images/p209.jpg" width="480" height="565" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_210" id="Page_210">[Pg 210]</a></span></p>
+
+<div class="figcenter" style="width: 624px;">
+<img src="images/p210.jpg" width="624" height="480" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_211" id="Page_211">[Pg 211]</a></span></p>
+
+<div class="figcenter" style="width: 587px;">
+<img src="images/p211.jpg" width="587" height="480" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_212" id="Page_212">[Pg 212]</a></span></p>
+
+<div class="figcenter" style="width: 480px;">
+<img src="images/p212.jpg" width="480" height="594" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_213" id="Page_213">[Pg 213]</a></span></p>
+
+<div class="figcenter" style="width: 480px;">
+<img src="images/p213.jpg" width="480" height="598" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_214" id="Page_214">[Pg 214]</a></span></p>
+
+<div class="figcenter" style="width: 480px;">
+<img src="images/p214.jpg" width="480" height="594" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_215" id="Page_215">[Pg 215]</a></span></p>
+
+<div class="figcenter" style="width: 480px;">
+<img src="images/p215.jpg" width="480" height="594" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_216" id="Page_216">[Pg 216]</a></span></p>
+
+<div class="figcenter" style="width: 616px;">
+<img src="images/p216.jpg" width="616" height="480" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_217" id="Page_217">[Pg 217]</a></span></p>
+
+<div class="figcenter" style="width: 640px;">
+<img src="images/p217.jpg" width="640" height="455" alt="" title="" />
+</div>
+<hr style="width: 30%;" />
+<p><span class='pagenum'><a name="Page_218" id="Page_218">[Pg 218]</a></span></p>
+
+<div class="figcenter" style="width: 640px;">
+<img src="images/p218.jpg" width="640" height="425" alt="" title="" />
+</div>
+
+
+
+<hr style="width: 65%;" /><p><span class='pagenum'><a name="Page_219" id="Page_219">[Pg 219]</a></span></p>
+<h2>Appendix</h2>
+
+<h3>Tables marked * are taken from the German Year Book for Soap Industry.</h3>
+
+<p><span class='pagenum'><a name="Page_220" id="Page_220">[Pg 220]</a></span></p>
+
+
+<h3>(U. S. BUREAU OF STANDARDS)</h3>
+
+<h4>THE METRIC SYSTEM.</h4>
+
+<p>The fundamental unit of the metric system is the meter (the unit of
+length). From this the units of mass (gram) and capacity (liter) are
+derived. All other units are the decimal sub-divisions or multiples of
+these. These three units are simply related, so that for all practical
+purposes the volume of one kilogram of water (one liter) is equal to one
+cubic decimeter.</p>
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Prefixes.</td><td align='left'> Meaning.</td><td align='left'> Units.</td></tr>
+<tr><td align='left'>Milli-</td><td align='left'> = one thousandth 1-1000 .001</td><td rowspan="3"> Meter for length.</td></tr>
+<tr><td align='left'>Centi-</td><td align='left'>= one hundredth 1-100 .01</td></tr>
+<tr><td align='left'>Deci-</td><td align='left'> = one tenth 1-10 .1</td></tr>
+<tr><td align='left'>Unit</td><td align='left'>= one 1.</td><td rowspan="2"> Gram for mass.</td></tr>
+<tr><td align='left'>Deka-</td><td align='left'> = ten 10-1 10.</td></tr>
+<tr><td align='left'>Hecto-</td><td align='left'> = one hundred 100-1 100.</td><td rowspan="2"> Liter for capacity.</td></tr>
+<tr><td align='left'>Kilo-</td><td align='left'>= one thousand 1000-1 1000.</td></tr>
+</table></div>
+
+
+<p>The metric terms are formed by combining the words "Meter," "Gram" and
+"Liter" with the six numerical prefixes.</p>
+
+
+<h4><span class="smcap">Length</span></h4>
+
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>10 milli-meters mm</td><td align='left'>=</td><td align='left'>1 centi-meter</td><td align='left'>c m</td></tr>
+<tr><td align='left'>10 centi-meters</td><td align='left'>=</td><td align='left'>1 deci-meter</td><td align='left'>d m</td></tr>
+<tr><td align='left'>10 deci-meters</td><td align='left'>=</td><td align='left'>1 meter (about 40 inches)</td><td align='left'>m</td></tr>
+<tr><td align='left'>10 meters</td><td align='left'>=</td><td align='left'>1 deka-meter</td><td align='left'>d k m</td></tr>
+<tr><td align='left'>10 deka-meters</td><td align='left'>=</td><td align='left'>1 hecto-meter</td><td align='left'>h m</td></tr>
+<tr><td align='left'>10 hecto-meters</td><td align='left'>=</td><td align='left'>1 kilo-meter (about 5/8 mile)</td><td align='left'>k m</td></tr>
+</table></div>
+
+<p>
+<span class='pagenum'><a name="Page_221" id="Page_221">[Pg 221]</a></span></p>
+
+
+<h4><span class="smcap">Mass.</span></h4>
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>10 milli-grams. m g</td><td align='left'>=</td><td align='left'>1 centi-gram</td><td align='left'>c g</td></tr>
+<tr><td align='left'>10 centi-grams</td><td align='left'>=</td><td align='left'>1 deci-gram</td><td align='left'>d g</td></tr>
+<tr><td align='left'>10 deci-grams</td><td align='left'>=</td><td align='left'>1 gram (about 15 grains)</td><td align='left'>g</td></tr>
+<tr><td align='left'>10 grams</td><td align='left'>=</td><td align='left'>1 deka-gram</td><td align='left'>d k g</td></tr>
+<tr><td align='left'>10 Deka-grams</td><td align='left'>=</td><td align='left'>1 hecto-gram</td><td align='left'>h g</td></tr>
+<tr><td align='left'>10 hecto-grams</td><td align='left'>=</td><td align='left'>1 kilo-gram (about 2 pounds)</td><td align='left'>k g</td></tr>
+</table></div>
+
+
+<h4><span class="smcap">Capacity.</span></h4>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>10 milli-liters. m l</td><td align='left'>=</td><td align='left'>1 centi-liter</td><td align='left'>c l</td></tr>
+<tr><td align='left'>10 centi-liters</td><td align='left'>=</td><td align='left'>1 deci-liter</td><td align='left'>d l</td></tr>
+<tr><td align='left'>10 deci-liters</td><td align='left'>=</td><td align='left'>1 liter (about 1 quart)</td><td align='left'>l</td></tr>
+<tr><td align='left'>10 liters</td><td align='left'>=</td><td align='left'>1 deka-liter</td><td align='left'>d k l</td></tr>
+<tr><td align='left'>10 deka-liters</td><td align='left'>=</td><td align='left'>1 hecto-liter (about a barrel)</td><td align='left'>h l</td></tr>
+<tr><td align='left'>10 hecto-liters</td><td align='left'>=</td><td align='left'>1 kilo-liter</td><td align='left'>k l</td></tr>
+</table></div>
+
+
+<p>The square and cubic units are the squares and cubes of the linear
+units.</p>
+
+<p>The ordinary unit of land area is the Hectare (about 2-1/2 acres).<span class='pagenum'><a name="Page_222" id="Page_222">[Pg 222]</a></span></p>
+
+
+<h3>U.S. BUREAU OF STANDARDS TABLE OF METRIC EQUIVALENTS</h3>
+
+
+<p>Meter = 39.37 inches.</p>
+
+<p>Legal Equivalent Adopted by Act of Congress July 28, 1866.</p>
+
+
+<h4><span class="smcap">Length.</span></h4>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Centimeter</td><td align='left'>= 0.3937 inch</td></tr>
+<tr><td align='left'>Meter</td><td align='left'>= 3.28 feet</td></tr>
+<tr><td align='left'>Meter</td><td align='left'>= 1.094 yards</td></tr>
+<tr><td align='left'>Kilometer</td><td align='left'>= 0.621 statute mile</td></tr>
+<tr><td align='left'>Kilometer</td><td align='left'>= 0.5396 nautical mile</td></tr>
+<tr><td align='left'>Inch</td><td align='left'>= 2.540 centimeters</td></tr>
+<tr><td align='left'>Foot</td><td align='left'>= 0.305 meter</td></tr>
+<tr><td align='left'>Yard</td><td align='left'>= 0.914 meter</td></tr>
+<tr><td align='left'>Statute mile</td><td align='left'>= 1.61 kilometers</td></tr>
+<tr><td align='left'>Nautical mile</td><td align='left'>= 1.853 kilometers</td></tr>
+</table></div>
+
+
+
+<h4><span class="smcap">Area.</span></h4>
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Sq. centimeter</td><td align='left'>= 0.155 sq. inch</td></tr>
+<tr><td align='left'>Sq. meter</td><td align='left'>= 10.76 sq. feet</td></tr>
+<tr><td align='left'>Sq. meter</td><td align='left'>= 1.196 sq. yards</td></tr>
+<tr><td align='left'>Hectare</td><td align='left'>= 2.47 acres</td></tr>
+<tr><td align='left'>Sq. kilometer</td><td align='left'>= 0.386 sq. mile</td></tr>
+<tr><td align='left'>Sq. inch</td><td align='left'>= 6.45 sq. centimeters</td></tr>
+<tr><td align='left'>Sq. foot</td><td align='left'>= 0.0929 sq. meter</td></tr>
+<tr><td align='left'>Sq. yard</td><td align='left'>= 0.836 sq. meter</td></tr>
+<tr><td align='left'>Acre</td><td align='left'>= 0.405 hectare</td></tr>
+<tr><td align='left'>Sq. mile</td><td align='left'>= 2.59 sq. kilometers</td></tr>
+</table></div>
+
+
+<p><span class='pagenum'><a name="Page_223" id="Page_223">[Pg 223]</a></span></p>
+
+
+<h4><span class="smcap">Weight.</span></h4>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Gram</td><td align='left'>= 15.43 grains</td></tr>
+<tr><td align='left'>Gram</td><td align='left'>= 0.772 U. S. apoth. scruple</td></tr>
+<tr><td align='left'>Gram</td><td align='left'>= 0.2572 U. S. apoth. dram</td></tr>
+<tr><td align='left'>Gram</td><td align='left'>= 0.0353 avoir. ounce</td></tr>
+<tr><td align='left'>Gram</td><td align='left'>= 0.03215 troy ounce</td></tr>
+<tr><td align='left'>Kilogram</td><td align='left'>= 2.205 avoir. pounds</td></tr>
+<tr><td align='left'>Kilogram</td><td align='left'>= 2.679 troy pounds</td></tr>
+<tr><td align='left'>Metric ton</td><td align='left'>= 0.984 gross or long ton</td></tr>
+<tr><td align='left'>Metric ton</td><td align='left'>= 1.102 short or net tons</td></tr>
+<tr><td align='left'>Grain</td><td align='left'>= 0.064 gram</td></tr>
+<tr><td align='left'>U. S. apoth. scruple</td><td align='left'>= 1.296 grams</td></tr>
+<tr><td align='left'>U. S. apoth. dram</td><td align='left'>= 3.89 grams</td></tr>
+<tr><td align='left'>Avoir. ounce</td><td align='left'>= 28.35 grams</td></tr>
+<tr><td align='left'>Troy ounce</td><td align='left'>= 31.10 grams</td></tr>
+<tr><td align='left'>Avoir. pound</td><td align='left'>= 0.4536 kilogram</td></tr>
+<tr><td align='left'>Troy pound</td><td align='left'>= 0.373 kilogram</td></tr>
+<tr><td align='left'>Gross or long ton</td><td align='left'>= 1.016 metric tons</td></tr>
+<tr><td align='left'>Short or net ton</td><td align='left'>= 0.907 metric ton</td></tr>
+</table></div>
+
+<h4><span class="smcap">Volume.</span></h4>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Cu. centimeter</td><td align='left'>= 0.0610 cu. inch</td></tr>
+<tr><td align='left'>Cu. meter</td><td align='left'>= 35.3 cu. feet</td></tr>
+<tr><td align='left'>Cu. meter</td><td align='left'>= 1.308 cu. yards</td></tr>
+<tr><td align='left'>Cu. inch</td><td align='left'>= 16.39 cu. centimeters</td></tr>
+<tr><td align='left'>Cu. foot</td><td align='left'>= 0.283 cu. meter</td></tr>
+<tr><td align='left'>Cu. yard</td><td align='left'>= 0.765 cu. meter</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_224" id="Page_224">[Pg 224]</a></span></p>
+
+
+<h4><span class="smcap">Capacity.</span></h4>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Millimeter</td><td align='left'>= 0.0338 U. S. liq. ounce</td></tr>
+<tr><td align='left'>Millimeter</td><td align='left'>= 0.2705 U. S. apoth. dram</td></tr>
+<tr><td align='left'>Liter</td><td align='left'>= 1.057 U. S. liq. quarts</td></tr>
+<tr><td align='left'>Liter</td><td align='left'>= 0.2642 U. S. liq. gallon</td></tr>
+<tr><td align='left'>Liter</td><td align='left'>= 0.908 U. S. dry quart</td></tr>
+<tr><td align='left'>Dekaliter</td><td align='left'>= 1.135 U. S. pecks</td></tr>
+<tr><td align='left'>Hectoliter</td><td align='left'>= 2.838 U. S. bushels</td></tr>
+<tr><td align='left'>U. S. liq. ounce</td><td align='left'>= 29.57 millimeters</td></tr>
+<tr><td align='left'>U. S. apoth. dram</td><td align='left'>= 3.70 millimeters</td></tr>
+<tr><td align='left'>U. S. liq. quarts</td><td align='left'>= 0.946 liter</td></tr>
+<tr><td align='left'>U. S. dry quarts</td><td align='left'>= 1.101 liters</td></tr>
+<tr><td align='left'>U. S. liq. gallon</td><td align='left'>= 3.785 liters</td></tr>
+<tr><td align='left'>U. S. peck</td><td align='left'>= 0.881 dekaliter</td></tr>
+<tr><td align='left'>U. S. bushel</td><td align='left'>= 0.3524 hectoliter</td></tr>
+</table></div>
+
+<h4>AVOIRDUPOIS WEIGHT.</h4>
+
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>1 pound</td><td align='left'>=</td><td align='left'>16 ounces</td><td align='left'>= 256</td><td align='left'>drams</td></tr>
+<tr><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td><td align='left'>1 ounce</td><td align='left'>= 16</td><td align='left'>"</td></tr>
+</table></div>
+
+
+<h4>TROY (APOTHECARIES') WEIGHT (U. S.)</h4>
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>1 pound</td><td align='left'>=</td><td align='left'>12 ounces</td><td align='left'>= 96 drams</td><td align='left'>= 288 scruples</td><td align='left'>= 5,760 grains</td></tr>
+<tr><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td><td align='left'>1 ounce</td><td align='left'>= 8 drams</td><td align='left'>= 24 scruples</td><td align='left'>= 480 grains</td></tr>
+<tr><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td><td align='left'>1 dram</td><td align='left'>= 3 scruples</td><td align='left'>= 60 grains</td></tr>
+<tr><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td><td align='left'>1 scruple</td><td align='left'>= 20 grains</td></tr>
+</table></div>
+
+
+
+<h4>WINE (APOTHECARIES) LIQUID MEASURE (U. S.)</h4>
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>1 gallon</td><td align='left'>= 8 pints</td><td align='left'>= 128 fl. ozs.</td><td align='left'>= 1,024 fl. drams</td><td align='left'>= 61,440 minims</td></tr>
+<tr><td align='left'>&nbsp;</td><td align='left'>1 pint</td><td align='left'>= 16 fl. ozs.</td><td align='left'>= 128 fl. drams</td><td align='left'>= 7,689 minims</td></tr>
+<tr><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td><td align='left'>1 fl. oz.</td><td align='left'>= 8 fl. drams</td><td align='left'>= 480 minims</td></tr>
+<tr><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td><td align='left'>1 fl. dram</td><td align='left'>= 60 minims</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_225" id="Page_225">[Pg 225]</a></span></p>
+
+<p><i>To find diameter of a circle</i> multiply circumference by .31831.</p>
+
+<p><i>To find circumference of a circle</i>, multiply diameter by 3.1416.</p>
+
+<p><i>To find area of a circle</i>, multiply square of diameter by .7854.</p>
+
+<p><i>To find surface of a ball</i>, multiply square of diameter by 3.1416.</p>
+
+<p><i>To find side of an equal square</i>, multiply diameter by .8862.</p>
+
+<p><i>To find cubic inches in a ball</i>, multiply cube of diameter by .5236.</p>
+
+<p><i>Doubling the diameter of a pipe</i>, increases its capacity four times.</p>
+
+<p><i>One cubic foot of anthracite coal</i> weighs about 53 lbs.</p>
+
+<p><i>One cubic foot of bituminous coal</i> weighs from 47 to 50 pounds.</p>
+
+<p><i>A gallon of water</i> (U. S. standard) weighs 8-1/3 pounds and contains
+231 cubic inches.</p>
+
+<p><i>A cubic foot of water</i> contains 7-1/2 gallons, 1728 cubic inches and
+weighs 62-1/2 pounds.</p>
+
+<p><i>To find the number of pounds of water a cylindrical</i> tank contains,
+square the diameter, multiply by .785 and then by the height in feet.
+This gives the number of cubic feet which multiplied by 62-1/2 gives the
+capacity in pounds of water. Divide by 7-1/2 and this gives the capacity
+in gallons.</p>
+
+<p><i>A horse-power</i> is equivalent to raising 33,000 pounds 1 foot per
+minute, or 550 pounds 1 foot per second.<span class='pagenum'><a name="Page_226" id="Page_226">[Pg 226]</a></span></p>
+
+<p><i>The friction of water in pipes</i> is as the square of velocity. The
+capacity of pipes is as the square of their diameters; thus, doubling
+the diameter of a pipe increases its capacity four times.</p>
+
+<p><i>To find the diameter of a pump cylinder</i> to move a given quantity of
+water per minute (100 feet of piston being the standard of speed),
+divide the number of gallons by 4, then extract the square root, and the
+product will be the diameter in inches of the pump cylinder.</p>
+
+<p><i>To find the horse-power necessary to elevate water</i> to a given height,
+multiply the weight of the water elevated per minute in pounds by the
+height in feet, and divide the product by 33,000 (an allowance should be
+added for water friction, and a further allowance for loss in steam
+cylinder, say from 20 to 30 per cent).</p>
+
+<p><i>To compute the capacity of pumping engines</i>, multiply the area of water
+piston, in inches, by the distance it travels, in inches, in a given
+time. Deduct 3 per cent for slip and rod displacement. The product
+divided by 231 gives the number of gallons in time named.</p>
+
+<p><i>To find the velocity in feet per minute</i> necessary to discharge a given
+volume of water in a given time, multiply the number of cubic feet of
+water by 144 and divide the product by the area of the pipe in inches.</p>
+
+<p><i>To find the area of a required pipe</i>, the volume and velocity of water
+being given, multiply the number of cubic feet of water by 144 and
+divide the product by the velocity in feet per minute. The area being
+found, the diameter can be learned by using any table giving the "area
+of circles" and finding the nearest area, opposite to which will be
+found the diameter to correspond.<span class='pagenum'><a name="Page_227" id="Page_227">[Pg 227]</a></span></p>
+
+
+<h3>Physical and Chemical Constants of Fixed Oils and Fats.</h3>
+
+<h4>(<span class="smcap">From Lewkowitsch and other authorities.</span>)</h4>
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'></td><td align='left'>Specific gravity at 15&deg;C.</td><td align='left'>Specific gravity at 100&deg;C.</td><td align='left'> Melting-point. C.</td><td align='left'> Solidifying-point. C.</td></tr>
+<tr><td align='left'>Linseed oil</td><td align='left'> 0.931-0.938</td><td align='left'> 0.880</td><td align='left'> -16&deg; to -26&deg;</td><td align='left'> -16&deg;</td></tr>
+<tr><td align='left'>Hemp-seed oil</td><td align='left'> 0.925-0.931</td><td align='left'></td><td align='left'></td><td align='left'> -27&deg;</td></tr>
+<tr><td align='left'>Walnut oil</td><td align='left'> 0.925-0.926</td><td align='left'> 0.871</td><td align='left'></td><td align='left'> -27&deg;</td></tr>
+<tr><td align='left'>Poppy-seed oil</td><td align='left'> 0.924-0.927</td><td align='left'> 0.873</td><td align='left'></td><td align='left'> -18&deg;</td></tr>
+<tr><td align='left'>Sunflower oil</td><td align='left'> 0.924-0.926</td><td align='left'> 0.919</td><td align='left'></td><td align='left'> -17&deg;</td></tr>
+<tr><td align='left'>Fir-seed oil</td><td align='left'> 0.925-0.928</td><td align='left'></td><td align='left'></td><td align='left'> -27&deg; to -30&deg;</td></tr>
+<tr><td align='left'>Maize oil</td><td align='left'> 0.921-0.926</td><td align='left'></td><td align='left'></td><td align='left'> -10&deg; to -15&deg;</td></tr>
+<tr><td align='left'>Cotton-seed oil</td><td align='left'> 0.922-0.930</td><td align='left'> 0.867</td><td align='left'></td><td align='left'> 12&deg;</td></tr>
+<tr><td align='left'>Sesame oil</td><td align='left'> 0.923-0.924</td><td align='left'> 0.871</td><td align='left'></td><td align='left'> -5&deg;</td></tr>
+<tr><td align='left'>Rape-seed oil</td><td align='left'> 0.914-0.917</td><td align='left'> 0.863</td><td align='left'></td><td align='left'> -2&deg; to -10&deg;</td></tr>
+<tr><td align='left'>Black mustard oil</td><td align='left'> 0.916-0.920</td><td align='left'></td><td align='left'></td><td align='left'> -17.5&deg;</td></tr>
+<tr><td align='left'>Croton oil</td><td align='left'> 0.942-0.955</td><td align='left'></td><td align='left'></td><td align='left'> -16&deg;</td></tr>
+<tr><td align='left'>Castor oil</td><td align='left'> 0.960-0.966</td><td align='left'> 0.910</td><td align='left'></td><td align='left'> -12&deg; to -18&deg;</td></tr>
+<tr><td align='left'>Apricot-kernel oil</td><td align='left'> 0.915-0.919</td><td align='left'></td><td align='left'></td><td align='left'> -14&deg;</td></tr>
+<tr><td align='left'>Almond oil</td><td align='left'> 0.915-0.920</td><td align='left'></td><td align='left'></td><td align='left'> -10&deg; to -20&deg;</td></tr>
+<tr><td align='left'>Peanut (arachis) oil</td><td align='left'> 0.916-0.920</td><td align='left'> 0.867</td><td align='left'></td><td align='left'> -3&deg; to -7&deg;</td></tr>
+<tr><td align='left'>Olive oil</td><td align='left'> 0.914-0.917</td><td align='left'> 0.862</td><td align='left'></td><td align='left'> 2&deg;</td></tr>
+<tr><td align='left'>Menhaden oil</td><td align='left'> 0.927-0.933</td><td align='left'></td><td align='left'></td><td align='left'> -4&deg;</td></tr>
+<tr><td align='left'>Cod-liver oil</td><td align='left'> 0.922-0.927</td><td align='left'> 0.874</td><td align='left'></td><td align='left'> 0&deg; to -10&deg;</td></tr>
+<tr><td align='left'>Seal oil</td><td align='left'> 0.924-0.929</td><td align='left'> 0.873</td><td align='left'></td><td align='left'> 3&deg;</td></tr>
+<tr><td align='left'>Whale oil</td><td align='left'> 0.920-0.930</td><td align='left'> 0.872</td><td align='left'></td><td align='left'> -2&deg;</td></tr>
+<tr><td align='left'>Dolphin oil</td><td align='left'> 0.917-0.918</td><td align='left'></td><td align='left'></td><td align='left'> 5&deg; to -3&deg;</td></tr>
+<tr><td align='left'>Porpoise oil</td><td align='left'> 0.926</td><td align='left'> 0.871</td><td align='left'></td><td align='left'> -16&deg;</td></tr>
+<tr><td align='left'>Neat's-foot oil</td><td align='left'> 0.914-0.916</td><td align='left'> 0.861</td><td align='left'></td><td align='left'> 0&deg; to 1.5&deg;</td></tr>
+<tr><td align='left'>Cotton-seed stearine</td><td align='left'> 0.919-0.923</td><td align='left'> 0.867</td><td align='left'> 40&deg;</td><td align='left'> 31&deg; to 32.5&deg;</td></tr>
+<tr><td align='left'>Palm oil</td><td align='left'> 0.921-0.925</td><td align='left'> 0.856</td><td align='left'> 27&deg; to 42&deg;</td></tr>
+<tr><td align='left'>Cacao butter</td><td align='left'> 0.950-0.952</td><td align='left'> 0.858</td><td align='left'> 30&deg; to 33&deg;</td><td align='left'> 25&deg; to 26&deg;</td></tr>
+<tr><td align='left'>Cocoa-nut oil</td><td align='left'> 0.925-0.926</td><td align='left'> 0.873</td><td align='left'> 20&deg; to 26&deg;</td><td align='left'> 16&deg; to 20&deg;</td></tr>
+<tr><td align='left'>Myrtle wax</td><td align='left'> 0.995</td><td align='left'> 0.875</td><td align='left'> 40&deg; to 44&deg;</td><td align='left'> 39&deg; to 43&deg;</td></tr>
+<tr><td align='left'>Japan wax</td><td align='left'> 0.970-0.980</td><td align='left'> 0.875</td><td align='left'> 51&deg; to 54.5&deg;</td><td align='left'> 46&deg;</td></tr>
+<tr><td align='left'>Lard</td><td align='left'> 0.931-0.938</td><td align='left'> 0.861</td><td align='left'> 41&deg; to 46&deg;</td><td align='left'> 29&deg;</td></tr>
+<tr><td align='left'>Bone fat</td><td align='left'> 0.914-0.916</td><td align='left'></td><td align='left'> 21&deg; to 22&deg;</td><td align='left'> 15&deg; to 17&deg;</td></tr>
+<tr><td align='left'>Tallow</td><td align='left'> 0.943-0.952</td><td align='left'> 0.860</td><td align='left'> 42&deg; to 46&deg;</td><td align='left'> 35&deg; to 37&deg;</td></tr>
+<tr><td align='left'>Butter fat</td><td align='left'> 0.927-0.936</td><td align='left'> 0.866</td><td align='left'> 29.5&deg; to 33&deg;</td><td align='left'> 19&deg; to 20&deg;</td></tr>
+<tr><td align='left'>Oleomargarine</td><td align='left'> 0.924-0.930</td><td align='left'> 0.859</td><td align='left'></td></tr>
+<tr><td align='left'>Sperm oil</td><td align='left'> 0.875-0.884</td><td align='left'> 0.833</td><td align='left'></td><td align='left'> -25&deg;</td></tr>
+<tr><td align='left'>Bottle-nose oil</td><td align='left'> 0.879-0.880</td><td align='left'> 0.827</td><td align='left'></td></tr>
+<tr><td align='left'>Carnauba wax</td><td align='left'> 0.990-0.999</td><td align='left'> 0.842</td><td align='left'> 84&deg; to 85&deg;</td><td align='left'> 80&deg; to 81&deg;</td></tr>
+<tr><td align='left'>Wool-fat</td><td align='left'> 0.973</td><td align='left'> 0.901</td><td align='left'> 39&deg; to 42&deg;</td><td align='left'> 30&deg; to 30.2&deg;</td></tr>
+<tr><td align='left'>Beeswax</td><td align='left'> 0.958-0.969</td><td align='left'> 0.822</td><td align='left'> 62&deg; to 64&deg;</td><td align='left'> 60.5&deg; to 62&deg;</td></tr>
+<tr><td align='left'>Spermaceti</td><td align='left'> 0.960</td><td align='left'> 0.812</td><td align='left'> 43.5&deg; to 49&deg;</td><td align='left'> 43.4&deg; to 44.2&deg;</td></tr>
+<tr><td align='left'>Chinese wax</td><td align='left'> 0.970</td><td align='left'> 0.810</td><td align='left'> 80.5&deg; to 81&deg;</td><td align='left'> 80.5&deg; to 81&deg;</td></tr>
+<tr><td align='left'>Tung (Chinese wood oil)</td><td align='left'> 0.936-0.942</td><td align='left'></td><td align='left'></td><td align='left'> below -17&deg;</td></tr>
+<tr><td align='left'>Soya-bean oil</td><td align='left'> 0.924-0.927</td><td align='left'></td><td align='left'></td><td align='left'> 8&deg; to 15&deg;</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_228" id="Page_228">[Pg 228]</a></span></p>
+
+
+<h3>Physical and Chemical Constants of Fixed Oils and Fats.</h3>
+
+<h4>(<span class="smcap">From Lewkowitsch and other Authorities.</span>)</h4>
+
+<div class='center'>
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'></td><td align='left'> Saponification value.</td><td align='left'> Maumen&eacute; test.</td><td align='left'> Iodine value.</td><td align='left'> Hehner value.</td><td align='left'> Reichert value.</td></tr>
+<tr><td align='left'>Linseed oil</td><td align='left'> 190-195</td><td align='left'> 104&deg;-111&deg;</td><td align='left'> 175-190</td><td align='left'></td></tr>
+<tr><td align='left'>Hemp-seed oil</td><td align='left'> 190-193</td><td align='left'> 95&deg;-96&deg;</td><td align='left'> 148</td><td align='left'></td></tr>
+<tr><td align='left'>Walnut oil</td><td align='left'> 195</td><td align='left'> 96&deg;-101&deg;</td><td align='left'> 144-147</td><td align='left'></td></tr>
+<tr><td align='left'>Poppy-seed oil</td><td align='left'> 195</td><td align='left'> 86&deg;-88&deg;</td><td align='left'> 134-141</td><td align='left'> 95.38</td></tr>
+<tr><td align='left'>Sunflower oil</td><td align='left'> 193-194</td><td align='left'> 72&deg;-75&deg;</td><td align='left'> 120-129</td><td align='left'> 95</td></tr>
+<tr><td align='left'>Fir-seed oil</td><td align='left'> 191.3</td><td align='left'> 98&deg;-99&deg;</td><td align='left'> 118.9-120</td><td align='left'></td></tr>
+<tr><td align='left'>Maize oil</td><td align='left'> 188-193</td><td align='left'> 56&deg;-60.5&deg;</td><td align='left'> 117-125</td><td align='left'> 89-95.7</td><td align='left'>2.5</td></tr>
+<tr><td align='left'>Cotton-seed oil</td><td align='left'> 191-195</td><td align='left'> 68&deg;-77&deg;</td><td align='left'> 104-110</td><td align='left'> 96-17</td></tr>
+<tr><td align='left'>Sesame oil</td><td align='left'> 189-193</td><td align='left'> 64&deg;-68&deg;</td><td align='left'> 105-109</td><td align='left'> 95.8</td><td align='left'>0.35</td></tr>
+<tr><td align='left'>Rape-seed oil</td><td align='left'> 170-178</td><td align='left'> 51&deg;-60&deg;</td><td align='left'> 95-105</td><td align='left'> 95</td></tr>
+<tr><td align='left'>Black mustard oil</td><td align='left'> 174-174.6</td><td align='left'> 43&deg;-44&deg;</td><td align='left'> 96-110</td><td align='left'> 95.05</td></tr>
+<tr><td align='left'>Croton oil</td><td align='left'> 210.3-215</td><td align='left'></td><td align='left'> 101.7-104</td><td align='left'> 89</td><td align='left'>13.5</td></tr>
+<tr><td align='left'>Castor oil</td><td align='left'> 178-186</td><td align='left'> 46&deg;-47&deg;</td><td align='left'> 83.4-85.9</td><td align='left'></td><td align='left'>1.4</td></tr>
+<tr><td align='left'>Apricot-kernel oil</td><td align='left'> 192.2-193.1</td><td align='left'> 42.5&deg;-46&deg;</td><td align='left'> 100-107</td><td align='left'></td></tr>
+<tr><td align='left'>Almond oil</td><td align='left'> 190.5-195.4</td><td align='left'> 51&deg;-54&deg;</td><td align='left'> 93-97</td><td align='left'> 96.2</td></tr>
+<tr><td align='left'>Peanut (arachis) oil</td><td align='left'> 190-197</td><td align='left'> 45&deg;-49&deg;</td><td align='left'> 85-98</td><td align='left'> 95.86</td></tr>
+<tr><td align='left'>Olive oil</td><td align='left'> 191-196</td><td align='left'> 41.5&deg;-45.5&deg;</td><td align='left'> 80.6-84.5</td><td align='left'> 95.43</td><td align='left'>0.3</td></tr>
+<tr><td align='left'>Menhaden oil</td><td align='left'> 189.3-192</td><td align='left'> 123&deg;-128&deg;</td><td align='left'> 140-170</td><td align='left'></td><td align='left'>1.2</td></tr>
+<tr><td align='left'>Cod-liver oil</td><td align='left'> 182-187</td><td align='left'> 102&deg;-103&deg;</td><td align='left'> 154-180</td><td align='left'> 95.3</td></tr>
+<tr><td align='left'>Seal oil</td><td align='left'> 190-196</td><td align='left'> 92&deg;</td><td align='left'> 127-140</td><td align='left'> 94.2</td><td align='left'>0.22</td></tr>
+<tr><td align='left'>Whale-oil</td><td align='left'> 188-193</td><td align='left'> 91&deg;-92&deg;</td><td align='left'> 110-136</td><td align='left'> 93.5</td><td align='left'>2.04</td></tr>
+<tr><td align='left'>Dolphin {Body oil</td><td align='left'> 197.3</td><td align='left'></td><td align='left'> 99.5</td><td align='left'> 93.07</td><td align='left'>5.6</td></tr>
+<tr><td align='left'>&nbsp;&nbsp;oil {Jaw oil</td><td align='left'> 200</td><td align='left'></td><td align='left'> 32.8</td><td align='left'> 66.28</td><td align='left'>65.92</td></tr>
+<tr><td align='left'>Porpoise {Body oil</td><td align='left'> 216-218.8</td><td align='left'> 50&deg;</td><td align='left'> 119.4</td><td align='left'></td><td align='left'>23.45</td></tr>
+<tr><td align='left'>&nbsp;&nbsp;oil {Jaw oil</td><td align='left'> 253.7</td><td align='left'></td><td align='left'> 49.6</td><td align='left'> 68.41</td><td align='left'>65.8</td></tr>
+<tr><td align='left'>Neat's-foot oil</td><td align='left'> 194.3</td><td align='left'> 47&deg;-48.5&deg;</td><td align='left'> 69.3-70.4</td><td align='left'></td></tr>
+<tr><td align='left'>Cotton-seed stearine.</td><td align='left'> 194.6-195.1</td><td align='left'> 48&deg;</td><td align='left'> 88.7-92.8</td><td align='left'> 96.3</td></tr>
+<tr><td align='left'>Palm oil</td><td align='left'> 196.3-202</td><td align='left'></td><td align='left'> 53-57</td><td align='left'> 95.6</td><td align='left'>0.5</td></tr>
+<tr><td align='left'>Cacao butter</td><td align='left'> 192.2-193.5</td><td align='left'></td><td align='left'> 32-41</td><td align='left'> 94.59</td><td align='left'>1.6</td></tr>
+<tr><td align='left'>Cocoa-nut oil</td><td align='left'> 250-253</td><td align='left'></td><td align='left'> 8.5-9.3</td><td align='left'> 88.6</td><td align='left'>3.7</td></tr>
+<tr><td align='left'>Myrtle wax</td><td align='left'> 205.7-211.7</td><td align='left'></td><td align='left'> 2.9</td><td align='left'></td></tr>
+<tr><td align='left'>Japan wax</td><td align='left'> 220-222.4</td><td align='left'></td><td align='left'> 4.2-8.5</td><td align='left'> 90.6</td></tr>
+<tr><td align='left'>Lard</td><td align='left'> 195.3-196.6</td><td align='left'> 27&deg;-32&deg;</td><td align='left'> 57-70</td><td align='left'> 96</td></tr>
+<tr><td align='left'>Bone fat</td><td align='left'> 190.9</td><td align='left'></td><td align='left'> 46.3-49.6</td><td align='left'></td></tr>
+<tr><td align='left'>Tallow</td><td align='left'> 195-198</td><td align='left'></td><td align='left'> 36-47</td><td align='left'> 95.6</td><td align='left'>0.25</td></tr>
+<tr><td align='left'>Butter fat</td><td align='left'> 221.5-227</td><td align='left'></td><td align='left'> 26-35</td><td align='left'> 87.5</td><td align='left'>28.78</td></tr>
+<tr><td align='left'>Oleomargarine</td><td align='left'> 194-203.7</td><td align='left'></td><td align='left'> 55.3-60</td><td align='left'> 95-96</td><td align='left'> 2.6</td></tr>
+<tr><td align='left'>Sperm oil</td><td align='left'> 132.5-147</td><td align='left'> 47&deg;-51&deg;</td><td align='left'> 84</td><td align='left'></td><td align='left'>1.3</td></tr>
+<tr><td align='left'>Bottle-nose oil</td><td align='left'> 126-134</td><td align='left'> 41&deg;-47&deg;</td><td align='left'> 77.4-82</td><td align='left'></td><td align='left'>1.4</td></tr>
+<tr><td align='left'>Carnauba wax</td><td align='left'> 80-84</td><td align='left'></td><td align='left'> 13.5</td><td align='left'></td></tr>
+<tr><td align='left'>Wool-fat</td><td align='left'> 98.2-102.4</td><td align='left'></td><td align='left'> 25-28</td><td align='left'></td></tr>
+<tr><td align='left'>Beeswax</td><td align='left'> 91-96</td><td align='left'></td><td align='left'> 8.3-11</td><td align='left'></td></tr>
+<tr><td align='left'>Spermaceti</td><td align='left'> 128</td><td align='left'></td><td align='left'></td><td align='left'></td></tr>
+<tr><td align='left'>Chinese wax</td><td align='left'> 63</td><td align='left'></td><td align='left'></td><td align='left'></td></tr>
+<tr><td align='left'>Tung (Chinese wood oil)</td><td align='left'> 193</td><td align='left'></td><td align='left'> 150-165</td><td align='left'></td></tr>
+<tr><td align='left'>Soya-bean oil</td><td align='left'> 190.6-192.9</td><td align='left'> 59&deg;-61&deg;</td><td align='left'> 121.3-124</td><td align='left'> 95.5</td></tr>
+</table></div>
+<p><span class='pagenum'><a name="Page_229" id="Page_229">[Pg 229]</a></span></p>
+
+
+<h3>*Temperature Correction Table for Hehner's Concentrated Bichromate
+Solution for Glycerine Analysis</h3>
+
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>A Temperature</td><td align='left'>f Corrected Volume 1 c.c.</td><td align='left'> Logarithm</td></tr>
+<tr><td align='left'>11&deg; C</td><td align='left'> 0.9980 ccm</td><td align='left'> 99913</td></tr>
+<tr><td align='left'>12&deg; "</td><td align='left'> 0.9985 "</td><td align='left'> 99935</td></tr>
+<tr><td align='left'>13&deg; "</td><td align='left'> 0.9990 "</td><td align='left'> 99956</td></tr>
+<tr><td align='left'>14&deg; "</td><td align='left'> 0.9995 "</td><td align='left'> 99978</td></tr>
+<tr><td align='left'>15&deg; "</td><td align='left'> 1.0000 "</td><td align='left'> 00000</td></tr>
+<tr><td align='left'>16&deg; "</td><td align='left'> 1.0005 "</td><td align='left'> 00022</td></tr>
+<tr><td align='left'>17&deg; "</td><td align='left'> 1.0010 "</td><td align='left'> 00043</td></tr>
+<tr><td align='left'>18&deg; "</td><td align='left'> 1.0015 "</td><td align='left'> 00065</td></tr>
+<tr><td align='left'>19&deg; "</td><td align='left'> 1.0020 "</td><td align='left'> 00087</td></tr>
+<tr><td align='left'>20&deg; "</td><td align='left'> 1.0025 "</td><td align='left'> 00108</td></tr>
+<tr><td align='left'>21&deg; "</td><td align='left'> 1.0030 "</td><td align='left'> 00130</td></tr>
+<tr><td align='left'>22&deg; "</td><td align='left'> 1.0035 "</td><td align='left'> 00152</td></tr>
+<tr><td align='left'>23&deg; "</td><td align='left'> 1.0040 "</td><td align='left'> 00173</td></tr>
+</table></div>
+<h3>*Table of Important Fatty Acids</h3>
+
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'></td><td align='left'></td><td align='left'></td><td colspan="2"> Boiling Point</td><td align='left'></td></tr>
+<tr><td align='left'>Name</td><td align='left'> Formula</td><td align='left'>Mol. Wt.</td><td align='left'>Ordinary Pressure</td><td align='left'>100 mm Pressure</td><td align='left'> Melting Pt.</td><td align='left'> Neutralization value Mg. KOH</td></tr>
+<tr><td align='left'>Butyric</td><td align='left'> C<sub>4</sub>H<sub>8</sub>O<sub>2</sub></td><td align='left'> 88</td><td align='left'> 162.3</td><td align='left'></td><td align='left'></td><td align='left'>637.5</td></tr>
+<tr><td align='left'>Caproic</td><td align='left'> C<sub>6</sub>H<sub>12</sub>O<sub>2</sub></td><td align='left'> 116</td><td align='left'> 199.7</td><td align='left'></td><td align='left'></td><td align='left'>483.6</td></tr>
+<tr><td align='left'>Caprylic</td><td align='left'> C<sub>8</sub>H<sub>16</sub>O<sub>2</sub></td><td align='left'> 144</td><td align='left'> 236-237</td><td align='left'></td><td align='left'> 16.5</td><td align='left'>389.6</td></tr>
+<tr><td align='left'>Capric</td><td align='left'> C<sub>10</sub>H<sub>20</sub>O<sub>2</sub></td><td align='left'> 172</td><td align='left'> 268-270</td><td align='left'> 199.5-200</td><td align='left'> 31.3</td><td align='left'>326.2</td></tr>
+<tr><td align='left'>Lauric</td><td align='left'> C<sub>12</sub>H<sub>24</sub>O<sub>2</sub></td><td align='left'> 200</td><td align='left'></td><td align='left'> 225</td><td align='left'> 43.6</td><td align='left'>280.5</td></tr>
+<tr><td align='left'>Myristic</td><td align='left'> C<sub>14</sub>H<sub>28</sub>O<sub>2</sub></td><td align='left'> 228</td><td align='left'></td><td align='left'> 250.5</td><td align='left'> 53.8</td><td align='left'>246.1</td></tr>
+<tr><td align='left'>Palmitic</td><td align='left'> C<sub>16</sub>H<sub>32</sub>O<sub>2</sub></td><td align='left'> 256</td><td align='left'></td><td align='left'> 268.5</td><td align='left'> 62</td><td align='left'>219.1</td></tr>
+<tr><td align='left'>Stearic</td><td align='left'> C<sub>18</sub>H<sub>36</sub>O<sub>2</sub></td><td align='left'> 284</td><td align='left'></td><td align='left'> 291</td><td align='left'> 69.2</td><td align='left'>197.5</td></tr>
+<tr><td align='left'>Arachidic</td><td align='left'> C<sub>20</sub>H<sub>40</sub>O<sub>2</sub></td><td align='left'> 302</td><td align='left'></td><td align='left'></td><td align='left'> 75</td><td align='left'>185.8</td></tr>
+<tr><td align='left'>Behenic</td><td align='left'> C<sub>22</sub>H<sub>44</sub>O<sub>2</sub></td><td align='left'> 330</td><td align='left'></td><td align='left'></td><td align='left'> 77-78</td><td align='left'>170.0</td></tr>
+<tr><td align='left'>Cerotic</td><td align='left'> C<sub>27</sub>H<sub>54</sub>O<sub>2</sub></td><td align='left'> 400</td><td align='left'></td><td align='left'></td><td align='left'> 78</td><td align='left'>140.25</td></tr>
+<tr><td align='left'>Melissic</td><td align='left'> C<sub>30</sub>H<sub>60</sub>O<sub>2</sub></td><td align='left'> 442</td><td align='left'></td><td align='left'></td><td align='left'> 90</td><td align='left'>126.5</td></tr>
+<tr><td align='left'>Oleic</td><td align='left'> C<sub>18</sub>H<sub>34</sub>O<sub>2</sub></td><td align='left'> 282</td><td align='left'></td><td align='left'> 185.5-286</td><td align='left'> 14</td><td align='left'>198.9</td></tr>
+<tr><td align='left'>Erucic</td><td align='left'> C<sub>22</sub>H<sub>42</sub>O<sub>2</sub></td><td align='left'> 338</td><td align='left'></td><td align='left'></td><td align='left'> 33-34</td><td align='left'>165.9</td></tr>
+<tr><td align='left'>Linolic</td><td align='left'> C<sub>18</sub>H<sub>32</sub>O<sub>2</sub></td><td align='left'> 280</td><td align='left'></td><td align='left'></td><td align='left'></td><td align='left'>200.4</td></tr>
+<tr><td align='left'>Linolenic</td><td align='left'> C<sub>18</sub>H<sub>30</sub>O<sub>2</sub></td><td align='left'> 278</td><td align='left'></td><td align='left'></td><td align='left'></td><td align='left'>201.5</td></tr>
+<tr><td align='left'>Ricinoleic</td><td align='left'> C<sub>18</sub>H<sub>34</sub>O<sub>3</sub></td><td align='left'> 298</td><td align='left'></td><td align='left'></td><td align='left'></td><td align='left'>181.6</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_230" id="Page_230">[Pg 230]</a></span></p>
+
+
+<h3>*Comparison of Thermometer Scales</h3>
+
+<p>n Degree Celsius = 4/5n Degree Reaumur = 32 + 9/5n Degree Fahrenheit</p>
+
+<p>n Degree Reaumur = 5/4n Degree Celsius = 32 + 9/4n Degree Fahrenheit</p>
+
+<p>n Degree Fahrenheit = 5/9 (n - 32) Degree Celsius = 4/9 (n - 32) Deg. R</p>
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'> C.</td><td align='left'> R.</td><td align='left'> F.</td><td align='left'></td><td align='left'> C.</td><td align='left'> R.</td><td align='left'> F.</td><td align='left'></td><td align='left'> C.</td><td align='left'> R.</td><td align='left'> F.</td><td align='left'></td><td align='left'> C.</td><td align='left'> R.</td><td align='left'> F.</td></tr>
+<tr><td align='left'>-20</td><td align='left'> -16</td><td align='left'> -4</td><td align='left'></td><td align='left'> 20</td><td align='left'> 16</td><td align='left'> 68</td><td align='left'></td><td align='left'> 60</td><td align='left'> 48</td><td align='left'> 140</td><td align='left'></td><td align='left'> 100</td><td align='left'> 80</td><td align='left'> 212</td></tr>
+<tr><td align='left'>-19</td><td align='left'>-15.2</td><td align='left'>-2.2</td><td align='left'></td><td align='left'> 21</td><td align='left'> 16.8</td><td align='left'> 69.8</td><td align='left'></td><td align='left'> 61</td><td align='left'> 48.8</td><td align='left'>141.8</td><td align='left'></td><td align='left'> 101</td><td align='left'> 80.8</td><td align='left'> 213.8</td></tr>
+<tr><td align='left'>-18</td><td align='left'>-14.4</td><td align='left'>-0.4</td><td align='left'></td><td align='left'> 22</td><td align='left'> 17.6</td><td align='left'> 71.6</td><td align='left'></td><td align='left'> 62</td><td align='left'> 49.6</td><td align='left'>143.6</td><td align='left'></td><td align='left'> 102</td><td align='left'> 81.6</td><td align='left'> 215.6</td></tr>
+<tr><td align='left'>-17</td><td align='left'>-13.6</td><td align='left'> 1.4</td><td align='left'></td><td align='left'> 23</td><td align='left'> 18.4</td><td align='left'> 73.4</td><td align='left'></td><td align='left'> 63</td><td align='left'> 50.4</td><td align='left'> 145.4</td><td align='left'></td><td align='left'> 103</td><td align='left'> 82.4</td><td align='left'> 217.4</td></tr>
+<tr><td align='left'>-16</td><td align='left'> -12.8</td><td align='left'> 3.2</td><td align='left'></td><td align='left'> 24</td><td align='left'> 19.2</td><td align='left'>75.2</td><td align='left'></td><td align='left'> 64</td><td align='left'> 51.2</td><td align='left'> 147.2</td><td align='left'></td><td align='left'> 104</td><td align='left'> 83.2</td><td align='left'> 219.2</td></tr>
+<tr><td align='left'>-15</td><td align='left'> -12</td><td align='left'> 5</td><td align='left'></td><td align='left'> 25</td><td align='left'> 20</td><td align='left'>77</td><td align='left'></td><td align='left'> 65</td><td align='left'> 52</td><td align='left'>149</td><td align='left'></td><td align='left'> 105</td><td align='left'> 84</td><td align='left'> 221</td></tr>
+<tr><td align='left'>-14</td><td align='left'> -11.2</td><td align='left'> 6.8</td><td align='left'></td><td align='left'> 26</td><td align='left'> 20.8</td><td align='left'> 78.8</td><td align='left'></td><td align='left'> 66</td><td align='left'> 52.8</td><td align='left'>150.8</td><td align='left'></td><td align='left'> 106</td><td align='left'> 84.8</td><td align='left'> 222.8</td></tr>
+<tr><td align='left'>-13</td><td align='left'> -10.4</td><td align='left'> 8.6</td><td align='left'></td><td align='left'> 27</td><td align='left'> 21.6</td><td align='left'> 80.6</td><td align='left'></td><td align='left'> 67</td><td align='left'> 53.6</td><td align='left'> 152.6</td><td align='left'></td><td align='left'> 107</td><td align='left'> 85.6</td><td align='left'> 224.6</td></tr>
+<tr><td align='left'>-12</td><td align='left'> -9.6</td><td align='left'> 10.4</td><td align='left'></td><td align='left'> 28</td><td align='left'> 22.4</td><td align='left'> 82.4</td><td align='left'></td><td align='left'> 68</td><td align='left'> 54.4</td><td align='left'>154.4</td><td align='left'></td><td align='left'> 108</td><td align='left'> 86.4</td><td align='left'> 226.4</td></tr>
+<tr><td align='left'>-11</td><td align='left'> -8.8</td><td align='left'> 12.2</td><td align='left'></td><td align='left'> 29</td><td align='left'> 23.2</td><td align='left'> 84.2</td><td align='left'></td><td align='left'> 69</td><td align='left'>55.2</td><td align='left'>156.2</td><td align='left'></td><td align='left'> 109</td><td align='left'> 87.2</td><td align='left'> 228.2</td></tr>
+<tr><td align='left'>-10</td><td align='left'> -8</td><td align='left'> 14</td><td align='left'></td><td align='left'> 30</td><td align='left'> 24</td><td align='left'> 86</td><td align='left'></td><td align='left'> 70</td><td align='left'> 56</td><td align='left'>158</td><td align='left'></td><td align='left'> 110</td><td align='left'> 88</td><td align='left'> 230</td></tr>
+<tr><td align='left'>-9</td><td align='left'> -7.2</td><td align='left'> 15.8</td><td align='left'></td><td align='left'> 31</td><td align='left'> 24.8</td><td align='left'> 87.8</td><td align='left'></td><td align='left'> 71</td><td align='left'> 56.8</td><td align='left'>159.8</td><td align='left'></td><td align='left'> 111</td><td align='left'> 88.8</td><td align='left'> 231.8</td></tr>
+<tr><td align='left'>-8</td><td align='left'> -6.4</td><td align='left'> 17.6</td><td align='left'></td><td align='left'> 32</td><td align='left'> 25.6</td><td align='left'>89.6</td><td align='left'></td><td align='left'> 72</td><td align='left'> 57.6</td><td align='left'> 161.6</td><td align='left'></td><td align='left'> 112</td><td align='left'> 89.6</td><td align='left'> 233.6</td></tr>
+<tr><td align='left'>-7</td><td align='left'> -5.6</td><td align='left'> 19.4</td><td align='left'></td><td align='left'> 33</td><td align='left'> 26.4</td><td align='left'>91.4</td><td align='left'></td><td align='left'> 73</td><td align='left'> 58.4</td><td align='left'>163.4</td><td align='left'></td><td align='left'> 113</td><td align='left'> 90.4</td><td align='left'> 235.4</td></tr>
+<tr><td align='left'>-6</td><td align='left'> -4.8</td><td align='left'> 21.2</td><td align='left'></td><td align='left'> 34</td><td align='left'> 27.2</td><td align='left'> 93.2</td><td align='left'></td><td align='left'> 74</td><td align='left'> 59.2</td><td align='left'> 165.2</td><td align='left'></td><td align='left'> 114</td><td align='left'> 91.2</td><td align='left'> 237.2</td></tr>
+<tr><td align='left'>-5</td><td align='left'> -4</td><td align='left'> 23</td><td align='left'></td><td align='left'> 35</td><td align='left'> 28</td><td align='left'> 95</td><td align='left'></td><td align='left'> 75</td><td align='left'> 60</td><td align='left'> 167</td><td align='left'></td><td align='left'> 115</td><td align='left'> 92</td><td align='left'> 239</td></tr>
+<tr><td align='left'>-4</td><td align='left'> -3.2</td><td align='left'> 24.8</td><td align='left'></td><td align='left'> 36</td><td align='left'> 28.8</td><td align='left'> 96.8</td><td align='left'></td><td align='left'> 76</td><td align='left'>60.8</td><td align='left'> 168.8</td><td align='left'></td><td align='left'> 116</td><td align='left'>92.8</td><td align='left'> 240.8</td></tr>
+<tr><td align='left'>-3</td><td align='left'> -2.4</td><td align='left'> 26.6</td><td align='left'></td><td align='left'> 37</td><td align='left'> 29.6</td><td align='left'> 98.6</td><td align='left'></td><td align='left'> 77</td><td align='left'>61.6</td><td align='left'>170.6</td><td align='left'></td><td align='left'> 117</td><td align='left'> 93.6</td><td align='left'> 242.6</td></tr>
+<tr><td align='left'>-2</td><td align='left'> -1.6</td><td align='left'> 28.4</td><td align='left'></td><td align='left'> 38</td><td align='left'> 30.4</td><td align='left'> 100.4</td><td align='left'></td><td align='left'> 78</td><td align='left'>62.4</td><td align='left'> 172.4</td><td align='left'></td><td align='left'> 118</td><td align='left'> 94.4</td><td align='left'> 244.4</td></tr>
+<tr><td align='left'>-1</td><td align='left'> -0.8</td><td align='left'> 30.2</td><td align='left'></td><td align='left'> 39</td><td align='left'> 31.2</td><td align='left'> 102.2</td><td align='left'></td><td align='left'> 79</td><td align='left'>63.2</td><td align='left'>174.2</td><td align='left'></td><td align='left'> 119</td><td align='left'> 95.2</td><td align='left'> 246.2</td></tr>
+<tr><td align='left'>0</td><td align='left'> 0</td><td align='left'> 32</td><td align='left'></td><td align='left'> 40</td><td align='left'> 32</td><td align='left'> 104</td><td align='left'></td><td align='left'> 80</td><td align='left'>64</td><td align='left'> 176</td><td align='left'></td><td align='left'> 120</td><td align='left'> 96</td><td align='left'> 248</td></tr>
+<tr><td align='left'>1</td><td align='left'> 0.8</td><td align='left'> 33.8</td><td align='left'></td><td align='left'> 41</td><td align='left'> 32.8</td><td align='left'> 105.8</td><td align='left'></td><td align='left'> 81</td><td align='left'> 64.8</td><td align='left'>177.8</td><td align='left'></td><td align='left'> 121</td><td align='left'> 96.8</td><td align='left'> 249.8</td></tr>
+<tr><td align='left'>2</td><td align='left'> 1.6</td><td align='left'> 35.6</td><td align='left'></td><td align='left'> 42</td><td align='left'> 33.6</td><td align='left'> 107.6</td><td align='left'></td><td align='left'> 82</td><td align='left'> 65.6</td><td align='left'>179.6</td><td align='left'></td><td align='left'> 122</td><td align='left'> 97.6</td><td align='left'> 252.6</td></tr>
+<tr><td align='left'>3</td><td align='left'> 2.4</td><td align='left'> 37.4</td><td align='left'></td><td align='left'> 43</td><td align='left'> 34.4</td><td align='left'> 109.4</td><td align='left'></td><td align='left'> 83</td><td align='left'> 66.4</td><td align='left'> 181.4</td><td align='left'></td><td align='left'> 123</td><td align='left'> 98.4</td><td align='left'> 253.4</td></tr>
+<tr><td align='left'>4</td><td align='left'> 3.2</td><td align='left'> 39.2</td><td align='left'></td><td align='left'> 44</td><td align='left'> 35.2</td><td align='left'> 111.2</td><td align='left'></td><td align='left'> 84</td><td align='left'> 67.2</td><td align='left'>183.2</td><td align='left'></td><td align='left'> 124</td><td align='left'> 99.2</td><td align='left'> 255.2</td></tr>
+<tr><td align='left'>5</td><td align='left'> 4</td><td align='left'> 41</td><td align='left'></td><td align='left'> 45</td><td align='left'> 36</td><td align='left'> 113</td><td align='left'></td><td align='left'> 85</td><td align='left'> 68</td><td align='left'> 185</td><td align='left'></td><td align='left'> 125</td><td align='left'> 100</td><td align='left'> 257</td></tr>
+<tr><td align='left'>6</td><td align='left'> 4.8</td><td align='left'> 42.8</td><td align='left'></td><td align='left'> 46</td><td align='left'>36.8</td><td align='left'>114.8</td><td align='left'></td><td align='left'> 86</td><td align='left'> 68.8</td><td align='left'> 186.8</td><td align='left'></td><td align='left'> 126</td><td align='left'> 100.8</td><td align='left'> 258.8</td></tr>
+<tr><td align='left'>7</td><td align='left'> 5.6</td><td align='left'> 44.6</td><td align='left'></td><td align='left'> 47</td><td align='left'>37.6</td><td align='left'> 116.6</td><td align='left'></td><td align='left'> 87</td><td align='left'> 69.6</td><td align='left'>188.6</td><td align='left'></td><td align='left'> 127</td><td align='left'> 101.6</td><td align='left'> 260.6</td></tr>
+<tr><td align='left'>8</td><td align='left'> 6.4</td><td align='left'> 46.4</td><td align='left'></td><td align='left'> 48</td><td align='left'>38.4</td><td align='left'>118.4</td><td align='left'></td><td align='left'> 88</td><td align='left'> 70.4</td><td align='left'>190.4</td><td align='left'></td><td align='left'> 128</td><td align='left'> 102.4</td><td align='left'> 262.4</td></tr>
+<tr><td align='left'>9</td><td align='left'> 7.2</td><td align='left'> 48.2</td><td align='left'></td><td align='left'> 49</td><td align='left'>39.2</td><td align='left'>120.2</td><td align='left'></td><td align='left'> 89</td><td align='left'> 71.2</td><td align='left'>192.2</td><td align='left'></td><td align='left'> 129</td><td align='left'> 103.2</td><td align='left'> 264.2</td></tr>
+<tr><td align='left'>10</td><td align='left'> 8</td><td align='left'> 50</td><td align='left'></td><td align='left'> 50</td><td align='left'> 40</td><td align='left'> 122</td><td align='left'></td><td align='left'> 90</td><td align='left'> 72</td><td align='left'> 194</td><td align='left'></td><td align='left'> 130</td><td align='left'> 104</td><td align='left'> 266</td></tr>
+<tr><td align='left'>11</td><td align='left'> 8.8</td><td align='left'> 51.8</td><td align='left'></td><td align='left'> 51</td><td align='left'> 40.8</td><td align='left'> 123.8</td><td align='left'></td><td align='left'> 91</td><td align='left'> 72.8</td><td align='left'> 195.8</td><td align='left'></td><td align='left'> 131</td><td align='left'> 104.8</td><td align='left'> 267.8</td></tr>
+<tr><td align='left'>12</td><td align='left'> 9.6</td><td align='left'> 53.6</td><td align='left'></td><td align='left'> 52</td><td align='left'> 41.6</td><td align='left'>125.6</td><td align='left'></td><td align='left'> 92</td><td align='left'> 73.6</td><td align='left'> 197.6</td><td align='left'></td><td align='left'> 132</td><td align='left'> 105.6</td><td align='left'> 269.6</td></tr>
+<tr><td align='left'>13</td><td align='left'> 10.4</td><td align='left'> 55.4</td><td align='left'></td><td align='left'> 53</td><td align='left'> 42.4</td><td align='left'> 127.4</td><td align='left'></td><td align='left'> 93</td><td align='left'>74.4</td><td align='left'> 199.4</td><td align='left'></td><td align='left'> 133</td><td align='left'> 106.4</td><td align='left'> 271.4</td></tr>
+<tr><td align='left'>14</td><td align='left'> 11.2</td><td align='left'> 57.2</td><td align='left'></td><td align='left'> 54</td><td align='left'> 43.2</td><td align='left'> 129.2</td><td align='left'></td><td align='left'> 94</td><td align='left'>75.2</td><td align='left'> 201.2</td><td align='left'></td><td align='left'> 134</td><td align='left'> 107.2</td><td align='left'> 273.2</td></tr>
+<tr><td align='left'>15</td><td align='left'> 12</td><td align='left'> 59</td><td align='left'></td><td align='left'> 55</td><td align='left'>44</td><td align='left'>131</td><td align='left'></td><td align='left'> 95</td><td align='left'> 76</td><td align='left'> 203</td><td align='left'></td><td align='left'> 135</td><td align='left'> 108</td><td align='left'> 275</td></tr>
+<tr><td align='left'>16</td><td align='left'> 12.8</td><td align='left'> 60.8</td><td align='left'></td><td align='left'> 56</td><td align='left'> 44.8</td><td align='left'>132.8</td><td align='left'></td><td align='left'> 96</td><td align='left'> 76.8</td><td align='left'>204.8</td><td align='left'></td><td align='left'> 136</td><td align='left'> 108.8</td><td align='left'> 276.8</td></tr>
+<tr><td align='left'>17</td><td align='left'> 13.6</td><td align='left'> 62.6</td><td align='left'></td><td align='left'> 57</td><td align='left'>45.6</td><td align='left'> 134.6</td><td align='left'></td><td align='left'> 97</td><td align='left'> 77.6</td><td align='left'> 206.6</td><td align='left'></td><td align='left'> 137</td><td align='left'> 109.6</td><td align='left'> 278.6</td></tr>
+<tr><td align='left'>18</td><td align='left'> 14.4</td><td align='left'> 64.4</td><td align='left'></td><td align='left'> 58</td><td align='left'>46.4</td><td align='left'>136.4</td><td align='left'></td><td align='left'> 98</td><td align='left'> 78.4</td><td align='left'>208.4</td><td align='left'></td><td align='left'> 138</td><td align='left'> 110.4</td><td align='left'> 280.4</td></tr>
+<tr><td align='left'>19</td><td align='left'> 15.2</td><td align='left'> 66.2</td><td align='left'></td><td align='left'> 59</td><td align='left'> 47.2</td><td align='left'> 138.2</td><td align='left'></td><td align='left'> 99</td><td align='left'> 79.2</td><td align='left'> 210.2</td><td align='left'></td><td align='left'> 139</td><td align='left'> 111.2</td><td align='left'> 282.2</td></tr>
+</table></div>
+
+
+<p><span class='pagenum'><a name="Page_231" id="Page_231">[Pg 231]</a></span></p>
+
+
+<h3>*Quantities of Alkali Required for Saponification of Fats of Average
+Molecular Weight 670</h3>
+
+<h4>(Cocoanut Oil, Palmkernel Oil)</h4>
+
+
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Kilos</td><td colspan="2"> Liters Alkali Solution Sp. Gr. 1.1</td><td colspan="2"> Liters Alkali Solution Sp. Gr. 1.2</td><td colspan="2"> Liters Alkali Solution Sp. Gr. 1.3</td><td colspan="2"> Liters Alkali Solution Sp. Gr. 1.355</td></tr>
+<tr><td align='left'></td><td align='left'> NaOH</td><td align='left'> KOH</td><td align='left'> NaOH</td><td align='left'> KOH</td><td align='left'> NaOH</td><td align='left'> KOH</td><td align='left'>NaOH</td><td align='left'> KOH</td></tr>
+<tr><td align='left'>1000</td><td align='left'> 1875.83</td><td align='left'> 1902.99</td><td align='left'> 844.67</td><td align='left'> 930.35</td><td align='left'> 510.27</td><td align='left'> 622.71</td><td align='left'>409.61</td><td align='left'> 517.97</td></tr>
+<tr><td align='left'>2000</td><td align='left'> 3751.66</td><td align='left'> 3805.97</td><td align='left'> 1689.35</td><td align='left'> 1860.70</td><td align='left'> 1020.64</td><td align='left'> 1245.41</td><td align='left'>819.21</td><td align='left'> 1035.95</td></tr>
+<tr><td align='left'>3000</td><td align='left'> 5627.50</td><td align='left'> 5708.96</td><td align='left'> 2534.02</td><td align='left'> 2791.04</td><td align='left'> 1530.81</td><td align='left'> 1868.12</td><td align='left'>1228.82</td><td align='left'> 1553.92</td></tr>
+<tr><td align='left'>4000</td><td align='left'> 7508.33</td><td align='left'> 7611.94</td><td align='left'> 3378.69</td><td align='left'> 3721.39</td><td align='left'> 2041.01</td><td align='left'> 2490.83</td><td align='left'>1638.43</td><td align='left'> 2071.90</td></tr>
+<tr><td align='left'>5000</td><td align='left'> 9379.16</td><td align='left'> 9514.93</td><td align='left'> 4223.37</td><td align='left'> 4651.74</td><td align='left'> 2551.35</td><td align='left'> 3113.54</td><td align='left'>2048.04</td><td align='left'> 2589.87</td></tr>
+<tr><td align='left'>6000</td><td align='left'> 11254.99</td><td align='left'> 11417.91</td><td align='left'> 5068.04</td><td align='left'> 5582.09</td><td align='left'> 3061.61</td><td align='left'> 3736.24</td><td align='left'>2457.65</td><td align='left'> 3107.84</td></tr>
+<tr><td align='left'>7000</td><td align='left'> 13130.82</td><td align='left'> 13320.90</td><td align='left'> 5912.71</td><td align='left'> 6512.44</td><td align='left'> 3571.88</td><td align='left'> 4358.95</td><td align='left'>2867.26</td><td align='left'> 3625.82</td></tr>
+<tr><td align='left'>8000</td><td align='left'> 15006.66</td><td align='left'> 15223.88</td><td align='left'> 6757.38</td><td align='left'> 7442.78</td><td align='left'> 4082.15</td><td align='left'> 4981.66</td><td align='left'>3276.86</td><td align='left'> 4143.79</td></tr>
+<tr><td align='left'>9000</td><td align='left'> 16882.49</td><td align='left'> 17126.87</td><td align='left'> 7602.06</td><td align='left'> 8373.13</td><td align='left'> 4592.42</td><td align='left'> 5604.36</td><td align='left'>3886.47</td><td align='left'> 4661.77</td></tr>
+<tr><td align='left'>10000</td><td align='left'> 18758.32</td><td align='left'> 19029.85</td><td align='left'> 8446.73</td><td align='left'> 9303.48</td><td align='left'> 5102.69</td><td align='left'> 6227.02</td><td align='left'>4096.08</td><td align='left'> 5179.74</td></tr>
+</table></div>
+
+
+<h3>*Quantities of Alkali Required for Saponification of Fats of Average
+Molecular Weight 860</h3>
+
+<h4>(Tallow, Cottonseed Oil, Olive Oil, Etc.)</h4>
+
+
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Kilos</td><td colspan="2"> Liters Alkali Solution Sp. Gr. 1.1</td><td colspan="2"> Liters Alkali Solution Sp. Gr. 1.2</td><td colspan="2"> Liters Alkali Solution Sp. Gr. 1.3</td><td colspan="2"> Liters Alkali Solution Sp. Gr. 1.355</td></tr>
+<tr><td align='left'></td><td align='left'> NaOH</td><td align='left'> KOH</td><td align='left'> NaOH</td><td align='left'> KOH</td><td align='left'> NaOH</td><td align='left'> KOH</td><td align='left'>NaOH</td><td align='left'> KOH</td></tr>
+<tr><td align='left'>1000</td><td align='left'> 1461.40</td><td align='left'> 1482.56</td><td align='left'> 658.05</td><td align='left'> 724.81</td><td align='left'> 397.54</td><td align='left'> 485.13</td><td align='left'>319.11</td><td align='left'> 403.54</td></tr>
+<tr><td align='left'>2000</td><td align='left'> 2922.81</td><td align='left'> 2965.12</td><td align='left'> 1316.12</td><td align='left'> 1449.61</td><td align='left'> 795.07</td><td align='left'> 970.27</td><td align='left'>638.23</td><td align='left'> 807.08</td></tr>
+<tr><td align='left'>3000</td><td align='left'> 4384.21</td><td align='left'> 4447.67</td><td align='left'> 1974.18</td><td align='left'> 2174.42</td><td align='left'> 1192.61</td><td align='left'> 1455.40</td><td align='left'>957.34</td><td align='left'> 1210.61</td></tr>
+<tr><td align='left'>4000</td><td align='left'> 5845.62</td><td align='left'> 5930.23</td><td align='left'> 2632.24</td><td align='left'> 2899.22</td><td align='left'> 1590.14</td><td align='left'> 1940.53</td><td align='left'>1276.45</td><td align='left'> 1614.15</td></tr>
+<tr><td align='left'>5000</td><td align='left'> 7307.02</td><td align='left'> 7412.79</td><td align='left'> 3290.80</td><td align='left'> 3624.03</td><td align='left'> 1987.68</td><td align='left'> 2425.67</td><td align='left'>1595.57</td><td align='left'> 2017.69</td></tr>
+<tr><td align='left'>6000</td><td align='left'> 8768.42</td><td align='left'> 8895.85</td><td align='left'> 3948.35</td><td align='left'> 4348.84</td><td align='left'> 2385.21</td><td align='left'> 2910.80</td><td align='left'>1914.68</td><td align='left'> 2421.23</td></tr>
+<tr><td align='left'>7000</td><td align='left'> 10229.83</td><td align='left'> 10377.91</td><td align='left'> 4606.41</td><td align='left'> 5073.64</td><td align='left'> 2782.75</td><td align='left'> 3395.93</td><td align='left'>2233.79</td><td align='left'> 2824.77</td></tr>
+<tr><td align='left'>8000</td><td align='left'> 11691.23</td><td align='left'> 11860.45</td><td align='left'> 5264.47</td><td align='left'> 5798.45</td><td align='left'> 3180.28</td><td align='left'> 3881.06</td><td align='left'>2552.90</td><td align='left'> 3228.30</td></tr>
+<tr><td align='left'>9000</td><td align='left'> 13152.64</td><td align='left'> 13343.02</td><td align='left'> 5922.53</td><td align='left'> 6523.25</td><td align='left'> 3577.82</td><td align='left'> 4366.20</td><td align='left'>2872.02</td><td align='left'> 3631.84</td></tr>
+<tr><td align='left'>10000</td><td align='left'> 14614.04</td><td align='left'> 14825.58</td><td align='left'> 6580.59</td><td align='left'> 7248.06</td><td align='left'> 3975.35</td><td align='left'> 4851.33</td><td align='left'>3191.13</td><td align='left'> 4035.38</td></tr>
+</table></div>
+
+
+<p><span class='pagenum'><a name="Page_232" id="Page_232">[Pg 232]</a></span></p>
+
+<h3>DENSITY AND STRENGTH OF SULPHURIC ACID (SIDERSKY).</h3>
+
+
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Degrees Twaddell.</td><td align='left'>Sp. Gr. at 15&deg; C.</td><td align='left'>% of pure acid (H<sub>2</sub>SO<sub>4</sub>).</td><td align='left'>Equivalent (in cc.) of a kilo of pure acid.</td><td align='left'>Equivalent (in cc.) of a liter of pure acid.</td></tr>
+<tr><td align='left'>1</td><td align='left'>1.007</td><td align='left'>1.9</td><td align='left'>52.620</td><td align='left'>96.930</td></tr>
+<tr><td align='left'>3</td><td align='left'>1.014</td><td align='left'>2.8</td><td align='left'>35.710</td><td align='left'>66.450</td></tr>
+<tr><td align='left'>4</td><td align='left'>1.022</td><td align='left'>3.8</td><td align='left'>25.650</td><td align='left'>47.230</td></tr>
+<tr><td align='left'>6</td><td align='left'>1.029</td><td align='left'>4.8</td><td align='left'>20.410</td><td align='left'>37.582</td></tr>
+<tr><td align='left'>8</td><td align='left'>1.037</td><td align='left'>5.8</td><td align='left'>16.670</td><td align='left'>30.690</td></tr>
+<tr><td align='left'>9</td><td align='left'>1.045</td><td align='left'>6.8</td><td align='left'>14.085</td><td align='left'>25.938</td></tr>
+<tr><td align='left'>10</td><td align='left'>1.052</td><td align='left'>7.8</td><td align='left'>12.198</td><td align='left'>22.460</td></tr>
+<tr><td align='left'>12</td><td align='left'>1.062</td><td align='left'>8.8</td><td align='left'>10.755</td><td align='left'>19.803</td></tr>
+<tr><td align='left'>13</td><td align='left'>1.067</td><td align='left'>9.8</td><td align='left'>9.524</td><td align='left'>17.540</td></tr>
+<tr><td align='left'>15</td><td align='left'>1.075</td><td align='left'>10.9</td><td align='left'>8.547</td><td align='left'>15.740</td></tr>
+<tr><td align='left'>17</td><td align='left'>1.083</td><td align='left'>11.9</td><td align='left'>7.752</td><td align='left'>14.278</td></tr>
+<tr><td align='left'>18</td><td align='left'>1.091</td><td align='left'>13.0</td><td align='left'>7.042</td><td align='left'>12.969</td></tr>
+<tr><td align='left'>20</td><td align='left'>1.100</td><td align='left'>14.1</td><td align='left'>6.452</td><td align='left'>11.882</td></tr>
+<tr><td align='left'>22</td><td align='left'>1.108</td><td align='left'>15.2</td><td align='left'>5.953</td><td align='left'>10.962</td></tr>
+<tr><td align='left'>23</td><td align='left'>1.116</td><td align='left'>16.2</td><td align='left'>5.526</td><td align='left'>10.177</td></tr>
+<tr><td align='left'>25</td><td align='left'>1.125</td><td align='left'>17.3</td><td align='left'>5.405</td><td align='left'>9.954</td></tr>
+<tr><td align='left'>27</td><td align='left'>1.134</td><td align='left'>18.5</td><td align='left'>4.76</td><td align='left'>8.770</td></tr>
+<tr><td align='left'>29</td><td align='left'>1.142</td><td align='left'>19.6</td><td align='left'>4.465</td><td align='left'>8.223</td></tr>
+<tr><td align='left'>30</td><td align='left'>1.152</td><td align='left'>20.8</td><td align='left'>4.184</td><td align='left'>7.723</td></tr>
+<tr><td align='left'>32</td><td align='left'>1.162</td><td align='left'>22.2</td><td align='left'>3.876</td><td align='left'>7.138</td></tr>
+<tr><td align='left'>34</td><td align='left'>1.171</td><td align='left'>23.3</td><td align='left'>3.663</td><td align='left'>6.745</td></tr>
+<tr><td align='left'>36</td><td align='left'>1.180</td><td align='left'>24.5</td><td align='left'>3.541</td><td align='left'>6.521</td></tr>
+<tr><td align='left'>38</td><td align='left'>1.190</td><td align='left'>25.8</td><td align='left'>3.258</td><td align='left'>5.999</td></tr>
+<tr><td align='left'>40</td><td align='left'>1.200</td><td align='left'>27.1</td><td align='left'>3.077</td><td align='left'>5.666</td></tr>
+<tr><td align='left'>42</td><td align='left'>1.210</td><td align='left'>28.4</td><td align='left'>2.907</td><td align='left'>5.353</td></tr>
+<tr><td align='left'>44</td><td align='left'>1.220</td><td align='left'>29.6</td><td align='left'>2.770</td><td align='left'>5.102</td></tr>
+<tr><td align='left'>46</td><td align='left'>1.231</td><td align='left'>31.0</td><td align='left'>2.618</td><td align='left'>4.865</td></tr>
+<tr><td align='left'>48</td><td align='left'>1.241</td><td align='left'>32.2</td><td align='left'>2.500</td><td align='left'>4.604</td></tr>
+<tr><td align='left'>50</td><td align='left'>1.252</td><td align='left'>33.4</td><td align='left'>2.392</td><td align='left'>4.406</td></tr>
+<tr><td align='left'>53</td><td align='left'>1.263</td><td align='left'>34.7</td><td align='left'>2.283</td><td align='left'>4.205</td></tr>
+<tr><td align='left'>55</td><td align='left'>1.274</td><td align='left'>36.0</td><td align='left'>2.179</td><td align='left'>4.012</td></tr>
+<tr><td align='left'>57</td><td align='left'>1.285</td><td align='left'>37.4</td><td align='left'>2.079</td><td align='left'>3.829</td></tr>
+<tr><td align='left'>60</td><td align='left'>1.297</td><td align='left'>38.8</td><td align='left'>1.988</td><td align='left'>3.661</td></tr>
+<tr><td align='left'>62</td><td align='left'>1.308</td><td align='left'>40.2</td><td align='left'>1.905</td><td align='left'>3.508</td></tr>
+<tr><td align='left'>64</td><td align='left'>1.320</td><td align='left'>41.6</td><td align='left'>1.821</td><td align='left'>3.354</td></tr>
+<tr><td align='left'>66</td><td align='left'>1.332</td><td align='left'>43.0</td><td align='left'>1.745</td><td align='left'>3.214</td></tr>
+<tr><td align='left'>69</td><td align='left'>1.345</td><td align='left'>44.4</td><td align='left'>1.665</td><td align='left'>3.085</td></tr>
+<tr><td align='left'>71</td><td align='left'>1.357</td><td align='left'>45.5</td><td align='left'>1.621</td><td align='left'>2.985</td></tr>
+<tr><td align='left'>74</td><td align='left'>1.370</td><td align='left'>46.9</td><td align='left'>1.558</td><td align='left'>2.869</td></tr>
+<tr><td align='left'>77</td><td align='left'>1.383</td><td align='left'>48.3</td><td align='left'>1.497</td><td align='left'>2.757</td></tr>
+<tr><td align='left'>80</td><td align='left'>1.397</td><td align='left'>49.8</td><td align='left'>1.436</td><td align='left'>2.646</td></tr>
+<tr><td align='left'>82</td><td align='left'>1.410</td><td align='left'>51.2</td><td align='left'>1.386</td><td align='left'>2.551</td></tr>
+<tr><td align='left'>85</td><td align='left'>1.424</td><td align='left'>52.6</td><td align='left'>1.335</td><td align='left'>2.459</td></tr>
+<tr><td align='left'>88</td><td align='left'>1.438</td><td align='left'>54.0</td><td align='left'>1.287</td><td align='left'>2.370</td></tr>
+<tr><td align='left'>91</td><td align='left'>1.453</td><td align='left'>55.4</td><td align='left'>1.237</td><td align='left'>2.270</td></tr>
+<tr><td align='left'>94</td><td align='left'>1.468</td><td align='left'>56.9</td><td align='left'>1.195</td><td align='left'>2.200</td></tr>
+<tr><td align='left'>97</td><td align='left'>1.483</td><td align='left'>58.3</td><td align='left'>1.156</td><td align='left'>2.130</td></tr>
+<tr><td align='left'>100</td><td align='left'>1.498</td><td align='left'>59.6</td><td align='left'>1.116</td><td align='left'>2.050</td></tr>
+<tr><td align='left'>103</td><td align='left'>1.514</td><td align='left'>61.0</td><td align='left'>1.080</td><td align='left'>1.980</td></tr>
+<tr><td align='left'>106</td><td align='left'>1.530</td><td align='left'>62.5</td><td align='left'>1.045</td><td align='left'>1.930</td></tr>
+<tr><td align='left'>108</td><td align='left'>1.540</td><td align='left'>64.0</td><td align='left'>1.010</td><td align='left'>1.860</td></tr>
+<tr><td align='left'>113</td><td align='left'>1.563</td><td align='left'>65.5</td><td align='left'>0.975</td><td align='left'>1.800</td></tr>
+<tr><td align='left'>116</td><td align='left'>1.580</td><td align='left'>67.0</td><td align='left'>0.950</td><td align='left'>1.740</td></tr>
+<tr><td align='left'>120</td><td align='left'>1.597</td><td align='left'>68.6</td><td align='left'>0.917</td><td align='left'>1.690</td></tr>
+<tr><td align='left'>123</td><td align='left'>1.615</td><td align='left'>70.0</td><td align='left'>0.888</td><td align='left'>1.630</td></tr>
+<tr><td align='left'>127</td><td align='left'>1.634</td><td align='left'>71.6</td><td align='left'>0.855</td><td align='left'>1.570</td></tr>
+<tr><td align='left'>130</td><td align='left'>1.652</td><td align='left'>73.2</td><td align='left'>0.845</td><td align='left'>1.520</td></tr>
+<tr><td align='left'>134</td><td align='left'>1.671</td><td align='left'>74.7</td><td align='left'>0.800</td><td align='left'>1.470</td></tr>
+<tr><td align='left'>138</td><td align='left'>1.691</td><td align='left'>76.4</td><td align='left'>0.774</td><td align='left'>1.430</td></tr>
+<tr><td align='left'>142</td><td align='left'>1.711</td><td align='left'>78.1</td><td align='left'>0.749</td><td align='left'>1.390</td></tr>
+<tr><td align='left'>146</td><td align='left'>1.732</td><td align='left'>79.9</td><td align='left'>0.722</td><td align='left'>1.320</td></tr>
+<tr><td align='left'>151</td><td align='left'>1.753</td><td align='left'>81.7</td><td align='left'>0.705</td><td align='left'>1.280</td></tr>
+<tr><td align='left'>155</td><td align='left'>1.774</td><td align='left'>84.1</td><td align='left'>0.672</td><td align='left'>1.235</td></tr>
+<tr><td align='left'>160</td><td align='left'>1.798</td><td align='left'>86.5</td><td align='left'>0.639</td><td align='left'>1.190</td></tr>
+<tr><td align='left'>164</td><td align='left'>1.819</td><td align='left'>89.7</td><td align='left'>0.609</td><td align='left'>1.120</td></tr>
+<tr><td align='left'>168</td><td align='left'>1.842</td><td align='left'>100.0</td><td align='left'>0.544</td><td align='left'>1.000</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_233" id="Page_233">[Pg 233]</a></span></p>
+
+
+<h3>*Densities of Potassium Carbonate Solutions at 15 C (Gerlach)</h3>
+
+
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Sp. Gr.</td><td align='left'> Per cent of<br /> pure K<sub>2</sub>CO<sub>3</sub></td></tr>
+<tr><td align='left'>1.00914</td><td align='left'> 1</td></tr>
+<tr><td align='left'>1.01829</td><td align='left'> 2</td></tr>
+<tr><td align='left'>1.02743</td><td align='left'> 3</td></tr>
+<tr><td align='left'>1.03658</td><td align='left'> 4</td></tr>
+<tr><td align='left'>1.04572</td><td align='left'> 5</td></tr>
+<tr><td align='left'>1.05513</td><td align='left'> 6</td></tr>
+<tr><td align='left'>1.06454</td><td align='left'> 7</td></tr>
+<tr><td align='left'>1.07396</td><td align='left'> 8</td></tr>
+<tr><td align='left'>1.08337</td><td align='left'> 9</td></tr>
+<tr><td align='left'>1.09278</td><td align='left'> 10</td></tr>
+<tr><td align='left'>1.10258</td><td align='left'> 11</td></tr>
+<tr><td align='left'>1.11238</td><td align='left'> 12</td></tr>
+<tr><td align='left'>1.12219</td><td align='left'> 13</td></tr>
+<tr><td align='left'>1.13199</td><td align='left'> 14</td></tr>
+<tr><td align='left'>1.14179</td><td align='left'> 15</td></tr>
+<tr><td align='left'>1.15200</td><td align='left'> 16</td></tr>
+<tr><td align='left'>1.16222</td><td align='left'> 17</td></tr>
+<tr><td align='left'>1.17243</td><td align='left'> 18</td></tr>
+<tr><td align='left'>1.18265</td><td align='left'> 19</td></tr>
+<tr><td align='left'>1.19286</td><td align='left'> 20</td></tr>
+<tr><td align='left'>1.20344</td><td align='left'> 21</td></tr>
+<tr><td align='left'>1.21402</td><td align='left'> 22</td></tr>
+<tr><td align='left'>1.22459</td><td align='left'> 23</td></tr>
+<tr><td align='left'>1.23517</td><td align='left'> 24</td></tr>
+<tr><td align='left'>1.24575</td><td align='left'> 25</td></tr>
+<tr><td align='left'>1.25681</td><td align='left'> 26</td></tr>
+<tr><td align='left'>1.26787</td><td align='left'> 27</td></tr>
+<tr><td align='left'>1.27893</td><td align='left'> 28</td></tr>
+<tr><td align='left'>1.28999</td><td align='left'> 29</td></tr>
+<tr><td align='left'>1.30105</td><td align='left'> 30</td></tr>
+<tr><td align='left'>1.31261</td><td align='left'> 31</td></tr>
+<tr><td align='left'>1.32417</td><td align='left'> 32</td></tr>
+<tr><td align='left'>1.33573</td><td align='left'> 33</td></tr>
+<tr><td align='left'>1.34729</td><td align='left'> 34</td></tr>
+<tr><td align='left'>1.35885</td><td align='left'> 35</td></tr>
+<tr><td align='left'>1.37082</td><td align='left'> 36</td></tr>
+<tr><td align='left'>1.38279</td><td align='left'> 37</td></tr>
+<tr><td align='left'>1.39476</td><td align='left'> 38</td></tr>
+<tr><td align='left'>1.40673</td><td align='left'> 39</td></tr>
+<tr><td align='left'>1.41870</td><td align='left'> 40</td></tr>
+<tr><td align='left'>1.43104</td><td align='left'> 41</td></tr>
+<tr><td align='left'>1.44338</td><td align='left'> 42</td></tr>
+<tr><td align='left'>1.45573</td><td align='left'> 43</td></tr>
+<tr><td align='left'>1.46807</td><td align='left'> 44</td></tr>
+<tr><td align='left'>1.48041</td><td align='left'> 45</td></tr>
+<tr><td align='left'>1.49314</td><td align='left'> 46</td></tr>
+<tr><td align='left'>1.50588</td><td align='left'> 47</td></tr>
+<tr><td align='left'>1.51861</td><td align='left'> 48</td></tr>
+<tr><td align='left'>1.53135</td><td align='left'> 49</td></tr>
+<tr><td align='left'>1.54408</td><td align='left'> 50</td></tr>
+<tr><td align='left'>1.55728</td><td align='left'> 51</td></tr>
+<tr><td align='left'>1.57048</td><td align='left'> 52</td></tr>
+<tr><td align='left'>1.57079</td><td align='left'> 53.024</td></tr>
+</table></div>
+
+
+<h3>*Constants of Certain Fatty Acids and Triglycerides</h3>
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td rowspan="2">Triglycerides of</td><td align='left'></td><td align='left'></td><td colspan="2"> Per cent Yield</td></tr>
+<tr><td align='left'>Mol. Wt. <br />of Fatty Acid</td><td align='left'> Mol. Wt. <br />of Triglycerides</td><td align='left'> Fatty Acid</td><td align='left'> Glycerine</td></tr>
+<tr><td align='left'>Stearic Acid</td><td align='left'> 284</td><td align='left'> 890</td><td align='left'> 95.73</td><td align='left'> 10.34</td></tr>
+<tr><td align='left'>Oleic Acid</td><td align='left'> 282</td><td align='left'> 884</td><td align='left'> 95.70</td><td align='left'> 10.41</td></tr>
+<tr><td align='left'>Margaric Acid</td><td align='left'> 270</td><td align='left'> 848</td><td align='left'> 95.52</td><td align='left'> 10.85</td></tr>
+<tr><td align='left'>Palmitic Acid</td><td align='left'> 256</td><td align='left'> 806</td><td align='left'> 95.28</td><td align='left'> 11.42</td></tr>
+<tr><td align='left'>Myristic Acid</td><td align='left'> 228</td><td align='left'> 722</td><td align='left'> 94.47</td><td align='left'> 12.74</td></tr>
+<tr><td align='left'>Lauric Acid</td><td align='left'> 200</td><td align='left'> 638</td><td align='left'> 94.04</td><td align='left'> 14.42</td></tr>
+<tr><td align='left'>Capric Acid</td><td align='left'> 172</td><td align='left'> 594</td><td align='left'> 93.14</td><td align='left'> 15.48</td></tr>
+<tr><td align='left'>Caproic Acid</td><td align='left'> 116</td><td align='left'> 386</td><td align='left'> 90.16</td><td align='left'> 23.83</td></tr>
+<tr><td align='left'>Butyric Acid</td><td align='left'> 88</td><td align='left'> 302</td><td align='left'> 87.41</td><td align='left'> 30.46</td></tr>
+</table></div>
+
+
+<p><span class='pagenum'><a name="Page_234" id="Page_234">[Pg 234]</a></span></p>
+
+
+<h3>PERCENTAGES OF SOLID CAUSTIC SODA AND CAUSTIC POTASH IN CAUSTIC LYES
+ACCORDING TO BAUME SCALE.</h3>
+
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Degrees Baum&eacute;.</td><td align='left'>% NaOH</td><td align='left'>% KOH</td></tr>
+<tr><td align='left'>1</td><td align='left'>0.61</td><td align='left'>0.90</td></tr>
+<tr><td align='left'>2</td><td align='left'>0.93</td><td align='left'>1.70</td></tr>
+<tr><td align='left'>3</td><td align='left'>2.00</td><td align='left'>2.60</td></tr>
+<tr><td align='left'>4</td><td align='left'>2.71</td><td align='left'>3.50</td></tr>
+<tr><td align='left'>5</td><td align='left'>3.35</td><td align='left'>4.50</td></tr>
+<tr><td align='left'>6</td><td align='left'>4.00</td><td align='left'>5.60</td></tr>
+<tr><td align='left'>7</td><td align='left'>4.556</td><td align='left'>6.286</td></tr>
+<tr><td align='left'>8</td><td align='left'>5.29</td><td align='left'>7.40</td></tr>
+<tr><td align='left'>9</td><td align='left'>5.87</td><td align='left'>8.20</td></tr>
+<tr><td align='left'>10</td><td align='left'>6.55</td><td align='left'>9.20</td></tr>
+<tr><td align='left'>11</td><td align='left'>7.31</td><td align='left'>10.10</td></tr>
+<tr><td align='left'>12</td><td align='left'>8.00</td><td align='left'>10.90</td></tr>
+<tr><td align='left'>13</td><td align='left'>8.68</td><td align='left'>12.00</td></tr>
+<tr><td align='left'>14</td><td align='left'>9.42</td><td align='left'>12.90</td></tr>
+<tr><td align='left'>15</td><td align='left'>10.06</td><td align='left'>13.80</td></tr>
+<tr><td align='left'>16</td><td align='left'>10.97</td><td align='left'>14.80</td></tr>
+<tr><td align='left'>17</td><td align='left'>11.84</td><td align='left'>15.70</td></tr>
+<tr><td align='left'>18</td><td align='left'>12.64</td><td align='left'>16.50</td></tr>
+<tr><td align='left'>19</td><td align='left'>13.55</td><td align='left'>17.60</td></tr>
+<tr><td align='left'>20</td><td align='left'>14.37</td><td align='left'>18.60</td></tr>
+<tr><td align='left'>21</td><td align='left'>15.13</td><td align='left'>19.50</td></tr>
+<tr><td align='left'>22</td><td align='left'>15.91</td><td align='left'>20.50</td></tr>
+<tr><td align='left'>23</td><td align='left'>16.77</td><td align='left'>21.40</td></tr>
+<tr><td align='left'>24</td><td align='left'>17.67</td><td align='left'>22.50</td></tr>
+<tr><td align='left'>25</td><td align='left'>18.58</td><td align='left'>23.30</td></tr>
+<tr><td align='left'>26</td><td align='left'>19.58</td><td align='left'>24.20</td></tr>
+<tr><td align='left'>27</td><td align='left'>20.59</td><td align='left'>25.10</td></tr>
+<tr><td align='left'>28</td><td align='left'>21.42</td><td align='left'>26.10</td></tr>
+<tr><td align='left'>29</td><td align='left'>22.64</td><td align='left'>27.00</td></tr>
+<tr><td align='left'>30</td><td align='left'>23.67</td><td align='left'>28.00</td></tr>
+<tr><td align='left'>31</td><td align='left'>24.81</td><td align='left'>28.90</td></tr>
+<tr><td align='left'>32</td><td align='left'>25.80</td><td align='left'>29.80</td></tr>
+<tr><td align='left'>33</td><td align='left'>26.83</td><td align='left'>30.70</td></tr>
+<tr><td align='left'>34</td><td align='left'>27.80</td><td align='left'>31.80</td></tr>
+<tr><td align='left'>35</td><td align='left'>28.83</td><td align='left'>32.70</td></tr>
+<tr><td align='left'>36</td><td align='left'>29.93</td><td align='left'>33.70</td></tr>
+<tr><td align='left'>37</td><td align='left'>31.22</td><td align='left'>34.90</td></tr>
+<tr><td align='left'>38</td><td align='left'>32.47</td><td align='left'>35.90</td></tr>
+<tr><td align='left'>39</td><td align='left'>33.69</td><td align='left'>36.90</td></tr>
+<tr><td align='left'>40</td><td align='left'>34.96</td><td align='left'>37.80</td></tr>
+<tr><td align='left'>41</td><td align='left'>36.25</td><td align='left'>38.90</td></tr>
+<tr><td align='left'>42</td><td align='left'>37.53</td><td align='left'>39.90</td></tr>
+<tr><td align='left'>43</td><td align='left'>38.80</td><td align='left'>40.90</td></tr>
+<tr><td align='left'>44</td><td align='left'>39.99</td><td align='left'>42.10</td></tr>
+<tr><td align='left'>45</td><td align='left'>41.41</td><td align='left'>43.40</td></tr>
+<tr><td align='left'>46</td><td align='left'>42.83</td><td align='left'>44.60</td></tr>
+<tr><td align='left'>47</td><td align='left'>44.38</td><td align='left'>45.80</td></tr>
+<tr><td align='left'>48</td><td align='left'>46.15</td><td align='left'>47.10</td></tr>
+<tr><td align='left'>49</td><td align='left'>47.58</td><td align='left'>48.25</td></tr>
+<tr><td align='left'>50</td><td align='left'>49.02</td><td align='left'>49.40</td></tr>
+</table></div>
+
+<h3>GLYCERINE CONTENT OF MORE COMMON OILS AND FATS USED IN SOAP MAKING.</h3>
+
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Kind.</td><td align='left'>Theoretical Yield<br /> of Pure Glycerine<br /> of Neutral Oil or Fat.</td><td align='left'>Average<br /> Free Fatty Acid<br /> in Commercial Oil.</td><td align='left'>% Pure Glycerine <br />in Commercial Oil.</td><td align='left'>Yield Soap Lye <br />80% Crude Glycerine.</td></tr>
+<tr><td align='left'>Beef Tallow</td><td align='left'>10.7</td><td align='left'>5</td><td align='left'>10.2</td><td align='left'>12.75</td></tr>
+<tr><td align='left'>Bone Grease</td><td align='left'>10.5</td><td align='left'>20-50</td><td align='left'>5.2- 8.4</td><td align='left'>6.5 -10.5</td></tr>
+<tr><td align='left'>Castor Oil</td><td align='left'>9.8</td><td align='left'>0.5-10</td><td align='left'>8.8- 9.8</td><td align='left'>11.0 -12.45</td></tr>
+<tr><td align='left'>Cocoanut Oil</td><td align='left'>13.9</td><td align='left'>3-5</td><td align='left'>13.2-13.5</td><td align='left'>16.5 -16.9</td></tr>
+<tr><td align='left'>Cocoanut Oil Off</td><td align='left'>15-40</td><td align='left'>8.3-11.8</td><td align='left'>10.37-14.75</td></tr>
+<tr><td align='left'>Corn Oil</td><td align='left'>10.4</td><td align='left'>1-10</td><td align='left'>9.3-10.3</td><td align='left'>11.62-12.9</td></tr>
+<tr><td align='left'>Cottonseed Oil</td><td align='left'>10.6</td><td align='left'>Trace</td><td align='left'>10.6</td><td align='left'>13.25</td></tr>
+<tr><td align='left'>Hog Grease</td><td align='left'>10.6</td><td align='left'>0.5-1</td><td align='left'>10.5-10.6</td><td align='left'>13.12-13.25</td></tr>
+<tr><td align='left'>Horse Grease</td><td align='left'>10.6</td><td align='left'>1-3</td><td align='left'>10.5-10.6</td><td align='left'>13.12-13.25</td></tr>
+<tr><td align='left'>Olive Oil</td><td align='left'>10.3</td><td align='left'>2-25</td><td align='left'>7.7-10.2</td><td align='left'>9.62-12.75</td></tr>
+<tr><td align='left'>Olive Foots</td><td align='left'>30-60</td><td align='left'>4-7</td><td align='left'>5- 8.75</td></tr>
+<tr><td align='left'>Palm Oil</td><td align='left'>11.0</td><td align='left'>10-50</td><td align='left'>5.5-10</td><td align='left'>6.87-12.5</td></tr>
+<tr><td align='left'>Palmkernel Oil</td><td align='left'>13.3</td><td align='left'>4-8</td><td align='left'>12.2-12.8</td><td align='left'>15.25-16</td></tr>
+<tr><td align='left'>Peanut Oil</td><td align='left'>10.4</td><td align='left'>5-20</td><td align='left'>8.3- 9.9</td><td align='left'>10.37-12.37</td></tr>
+<tr><td align='left'>Soya Bean Oil</td><td align='left'>10.4</td><td align='left'>2</td><td align='left'>10.2</td><td align='left'>12.75</td></tr>
+<tr><td align='left'>Train Oil</td><td align='left'>10.0</td><td align='left'>2-20</td><td align='left'>8- 9.8</td><td align='left'>10.0 -12.25</td></tr>
+<tr><td align='left'>Vegetable Tallow</td><td align='left'>10.9</td><td align='left'>1-3</td><td align='left'>10.5-10.8</td><td align='left'>13.12-13.5</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_235" id="Page_235">[Pg 235]</a></span></p>
+
+
+<h3>*Table of Specific Gravities of Pure Commercial Glycerine with
+Corresponding Percentage of Water. Temperature 15 C.
+</h3>
+
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Sp. Gr.</td><td align='left'> % Water</td><td align='left'></td><td align='left'> Sp. Gr.</td><td align='left'> % Water</td></tr>
+<tr><td align='left'>1.262</td><td align='left'> 0</td><td align='left'></td><td align='left'> 1.160</td><td align='left'> 38</td></tr>
+<tr><td align='left'>1.261</td><td align='left'> 1</td><td align='left'></td><td align='left'> 1.157</td><td align='left'> 39</td></tr>
+<tr><td align='left'>1.258</td><td align='left'> 2</td><td align='left'></td><td align='left'> 1.155</td><td align='left'> 40</td></tr>
+<tr><td align='left'>1.255</td><td align='left'> 3</td><td align='left'></td><td align='left'> 1.152</td><td align='left'> 41</td></tr>
+<tr><td align='left'>1.2515</td><td align='left'> 4</td><td align='left'></td><td align='left'> 1.149</td><td align='left'> 42</td></tr>
+<tr><td align='left'>1.250</td><td align='left'> 5</td><td align='left'></td><td align='left'> 1.1464</td><td align='left'> 43</td></tr>
+<tr><td align='left'>1.2467</td><td align='left'> 6</td><td align='left'></td><td align='left'> 1.1437</td><td align='left'> 44</td></tr>
+<tr><td align='left'>1.2450</td><td align='left'> 7</td><td align='left'></td><td align='left'> 1.141</td><td align='left'> 45</td></tr>
+<tr><td align='left'>1.243</td><td align='left'> 8</td><td align='left'></td><td align='left'> 1.1377</td><td align='left'> 46</td></tr>
+<tr><td align='left'>1.241</td><td align='left'> 9</td><td align='left'></td><td align='left'> 1.1353</td><td align='left'> 47</td></tr>
+<tr><td align='left'>1.237</td><td align='left'> 10</td><td align='left'></td><td align='left'> 1.1326</td><td align='left'> 48</td></tr>
+<tr><td align='left'>1.235</td><td align='left'> 11</td><td align='left'></td><td align='left'> 1.1304</td><td align='left'> 49</td></tr>
+<tr><td align='left'>1.2324</td><td align='left'> 12</td><td align='left'></td><td align='left'> 1.127</td><td align='left'> 50</td></tr>
+<tr><td align='left'>1.229</td><td align='left'> 13</td><td align='left'></td><td align='left'> 1.125</td><td align='left'> 51</td></tr>
+<tr><td align='left'>1.2265</td><td align='left'> 14</td><td align='left'></td><td align='left'> 1.1224</td><td align='left'> 52</td></tr>
+<tr><td align='left'>1.2245</td><td align='left'> 15</td><td align='left'></td><td align='left'> 1.1204</td><td align='left'> 53</td></tr>
+<tr><td align='left'>1.2225</td><td align='left'> 16</td><td align='left'></td><td align='left'> 1.117</td><td align='left'> 54</td></tr>
+<tr><td align='left'>1.2185</td><td align='left'> 17</td><td align='left'></td><td align='left'> 1.114</td><td align='left'> 55</td></tr>
+<tr><td align='left'>1.2174</td><td align='left'> 18</td><td align='left'></td><td align='left'> 1.112</td><td align='left'> 56</td></tr>
+<tr><td align='left'>1.2142</td><td align='left'> 19</td><td align='left'></td><td align='left'> 1.109</td><td align='left'> 57</td></tr>
+<tr><td align='left'>1.211</td><td align='left'> 20</td><td align='left'></td><td align='left'> 1.106</td><td align='left'> 58</td></tr>
+<tr><td align='left'>1.207</td><td align='left'> 21</td><td align='left'></td><td align='left'> 1.103</td><td align='left'> 59</td></tr>
+<tr><td align='left'>1.203</td><td align='left'> 22</td><td align='left'></td><td align='left'> 1.1006</td><td align='left'> 60</td></tr>
+<tr><td align='left'>1.2004</td><td align='left'> 23</td><td align='left'></td><td align='left'> 1.088</td><td align='left'> 65</td></tr>
+<tr><td align='left'>1.198</td><td align='left'> 24</td><td align='left'></td><td align='left'> 1.075</td><td align='left'> 70</td></tr>
+<tr><td align='left'>1.195</td><td align='left'> 25</td><td align='left'></td><td align='left'> 1.0623</td><td align='left'> 75</td></tr>
+<tr><td align='left'>1.1923</td><td align='left'> 26</td><td align='left'></td><td align='left'> 1.049</td><td align='left'> 80</td></tr>
+<tr><td align='left'>1.189</td><td align='left'> 27</td><td align='left'></td><td align='left'> 1.0365</td><td align='left'> 85</td></tr>
+<tr><td align='left'>1.188</td><td align='left'> 28</td><td align='left'></td><td align='left'> 1.0243</td><td align='left'> 90</td></tr>
+<tr><td align='left'>1.1846</td><td align='left'> 29</td><td align='left'></td><td align='left'> 1.0218</td><td align='left'> 91</td></tr>
+<tr><td align='left'>1.182</td><td align='left'> 30</td><td align='left'></td><td align='left'> 1.0192</td><td align='left'> 92</td></tr>
+<tr><td align='left'>1.179</td><td align='left'> 31</td><td align='left'></td><td align='left'> 1.0168</td><td align='left'> 93</td></tr>
+<tr><td align='left'>1.176</td><td align='left'> 32</td><td align='left'></td><td align='left'> 1.0147</td><td align='left'> 94</td></tr>
+<tr><td align='left'>1.1734</td><td align='left'> 33</td><td align='left'></td><td align='left'> 1.0125</td><td align='left'> 95</td></tr>
+<tr><td align='left'>1.171</td><td align='left'> 34</td><td align='left'></td><td align='left'> 1.01</td><td align='left'> 96</td></tr>
+<tr><td align='left'>1.168</td><td align='left'> 35</td><td align='left'></td><td align='left'> 1.0074</td><td align='left'> 97</td></tr>
+<tr><td align='left'>1.165</td><td align='left'> 36</td><td align='left'></td><td align='left'> 1.0053</td><td align='left'> 98</td></tr>
+<tr><td align='left'>1.163</td><td align='left'> 37</td><td align='left'></td><td align='left'> 1.0026</td><td align='left'> 99</td></tr>
+</table></div>
+
+<p><span class='pagenum'><a name="Page_236" id="Page_236">[Pg 236]</a></span></p>
+
+
+<h3>Table of Percentage, Specific Gravity and Beaume Degree of Pure
+Glycerine Solutions</h3>
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Per cent Water</td><td align='left'>Sp. Gr. Champion and Pellet</td><td align='left'>Degree Beaum&eacute; (Berthelot)</td><td align='left'></td><td align='left'>Per cent Water</td><td align='left'>Sp. Gr. Champion and Pellet</td><td align='left'>Degree Beaum&eacute; (Berthelot)</td></tr>
+<tr><td align='left'>0</td><td align='left'> 1.2640</td><td align='left'> 31.2</td><td align='left'></td><td align='left'> 11.0</td><td align='left'> 1.2350</td><td align='left'> 28.6</td></tr>
+<tr><td align='left'>0.5</td><td align='left'> 1.2625</td><td align='left'> 31.0</td><td align='left'></td><td align='left'> 11.5</td><td align='left'> 1.2335</td><td align='left'> 28.4</td></tr>
+<tr><td align='left'>1.0</td><td align='left'> 1.2612</td><td align='left'> 30.9</td><td align='left'></td><td align='left'> 12.0</td><td align='left'> 1.2322</td><td align='left'> 28.3</td></tr>
+<tr><td align='left'>1.5</td><td align='left'> 1.2600</td><td align='left'> 30.8</td><td align='left'></td><td align='left'> 12.5</td><td align='left'> 1.2307</td><td align='left'> 28.2</td></tr>
+<tr><td align='left'>2.0</td><td align='left'> 1.2585</td><td align='left'> 30.7</td><td align='left'></td><td align='left'> 13.0</td><td align='left'> 1.2295</td><td align='left'> 28.0</td></tr>
+<tr><td align='left'>2.5</td><td align='left'> 1.2575</td><td align='left'> 30.6</td><td align='left'></td><td align='left'> 13.5</td><td align='left'> 1.2280</td><td align='left'> 27.8</td></tr>
+<tr><td align='left'>3.0</td><td align='left'> 1.2560</td><td align='left'> 30.4</td><td align='left'></td><td align='left'> 14.0</td><td align='left'> 1.2270</td><td align='left'> 27.7</td></tr>
+<tr><td align='left'>3.5</td><td align='left'> 1.2545</td><td align='left'> 30.3</td><td align='left'></td><td align='left'> 14.5</td><td align='left'> 1.2255</td><td align='left'> 27.6</td></tr>
+<tr><td align='left'>4.0</td><td align='left'> 1.2532</td><td align='left'> 30.2</td><td align='left'></td><td align='left'> 15.0</td><td align='left'> 1.2242</td><td align='left'> 27.4</td></tr>
+<tr><td align='left'>4.5</td><td align='left'> 1.2520</td><td align='left'> 30.1</td><td align='left'></td><td align='left'> 15.5</td><td align='left'> 1.2230</td><td align='left'> 27.3</td></tr>
+<tr><td align='left'>5.0</td><td align='left'> 1.2505</td><td align='left'> 30.0</td><td align='left'></td><td align='left'> 16.0</td><td align='left'> 1.2217</td><td align='left'> 27.2</td></tr>
+<tr><td align='left'>5.5</td><td align='left'> 1.2490</td><td align='left'> 29.9</td><td align='left'></td><td align='left'> 16.5</td><td align='left'> 1.2202</td><td align='left'> 27.0</td></tr>
+<tr><td align='left'>6.0</td><td align='left'> 1.2480</td><td align='left'> 29.8</td><td align='left'></td><td align='left'> 17.0</td><td align='left'> 1.2190</td><td align='left'> 26.9</td></tr>
+<tr><td align='left'>6.5</td><td align='left'> 1.2465</td><td align='left'> 29.7</td><td align='left'></td><td align='left'> 17.5</td><td align='left'> 1.2177</td><td align='left'> 26.8</td></tr>
+<tr><td align='left'>7.0</td><td align='left'> 1.2455</td><td align='left'> 29.6</td><td align='left'></td><td align='left'> 18.0</td><td align='left'> 1.2165</td><td align='left'> 26.7</td></tr>
+<tr><td align='left'>7.5</td><td align='left'> 1.2440</td><td align='left'> 29.5</td><td align='left'></td><td align='left'> 18.5</td><td align='left'> 1.2150</td><td align='left'> 26.5</td></tr>
+<tr><td align='left'>8.0</td><td align='left'> 1.2427</td><td align='left'> 29.3</td><td align='left'></td><td align='left'> 19.0</td><td align='left'> 1.2137</td><td align='left'> 26.4</td></tr>
+<tr><td align='left'>8.5</td><td align='left'> 1.2412</td><td align='left'> 29.2</td><td align='left'></td><td align='left'> 19.5</td><td align='left'> 1.2125</td><td align='left'> 26.3</td></tr>
+<tr><td align='left'>9.0</td><td align='left'> 1.2400</td><td align='left'> 29.0</td><td align='left'></td><td align='left'> 20.0</td><td align='left'> 1.2112</td><td align='left'> 26.2</td></tr>
+<tr><td align='left'>9.5</td><td align='left'> 1.2390</td><td align='left'> 28.9</td><td align='left'></td><td align='left'> 20.5</td><td align='left'> 1.2100</td><td align='left'> 26.0</td></tr>
+<tr><td align='left'>10.0</td><td align='left'> 1.2375</td><td align='left'> 28.8</td><td align='left'></td><td align='left'> 21.0</td><td align='left'> 1.2085</td><td align='left'> 25.0</td></tr>
+<tr><td align='left'>10.5</td><td align='left'> 1.2362</td><td align='left'> 28.7</td><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td><td align='left'>&nbsp;</td></tr>
+</table></div>
+<p><span class='pagenum'><a name="Page_237" id="Page_237">[Pg 237]</a></span></p>
+
+
+<h3>*Table of Specific Gravities of Pure Glycerine Solutions with
+Corresponding Beaume Degree and Percent Water</h3>
+
+
+<div class='center'>
+<table border="1" cellpadding="4" cellspacing="0" summary="">
+<tr><td align='left'>Per cent Water</td><td align='left'>Sp. Gr.</td><td align='left'> Degree Beaume</td><td align='left'> Per cent Water</td><td align='left'>Sp. Gr.</td><td align='left'> Degree Beaume</td></tr>
+<tr><td align='left'>0.0</td><td align='left'> 1.2640</td><td align='left'> 31.2</td><td align='left'> 1.0</td><td align='left'> 1.2612</td><td align='left'> 30.9</td></tr>
+<tr><td align='left'>0.5</td><td align='left'> 1.2625</td><td align='left'> 31.0</td><td align='left'> 1.5</td><td align='left'> 1.2600</td><td align='left'> 30.8</td></tr>
+<tr><td align='left'>2.0</td><td align='left'> 1.2585</td><td align='left'> 30.7</td><td align='left'> 12.0</td><td align='left'> 1.2322</td><td align='left'> 28.3</td></tr>
+<tr><td align='left'>2.5</td><td align='left'> 1.2575</td><td align='left'> 30.6</td><td align='left'> 12.5</td><td align='left'> 1.2307</td><td align='left'> 28.2</td></tr>
+<tr><td align='left'>3.0</td><td align='left'> 1.2560</td><td align='left'> 30.4</td><td align='left'> 13.0</td><td align='left'> 1.2295</td><td align='left'> 28.0</td></tr>
+<tr><td align='left'>3.5</td><td align='left'> 1.2545</td><td align='left'> 30.3</td><td align='left'> 13.5</td><td align='left'> 1.2280</td><td align='left'> 27.8</td></tr>
+<tr><td align='left'>4.0</td><td align='left'> 1.2532</td><td align='left'> 30.2</td><td align='left'> 14.0</td><td align='left'> 1.2270</td><td align='left'> 27.7</td></tr>
+<tr><td align='left'>4.5</td><td align='left'> 1.2520</td><td align='left'> 30.1</td><td align='left'> 14.5</td><td align='left'> 1.2255</td><td align='left'> 27.6</td></tr>
+<tr><td align='left'>5.0</td><td align='left'> 1.2505</td><td align='left'> 30.0</td><td align='left'> 15.0</td><td align='left'> 1.2242</td><td align='left'> 27.4</td></tr>
+<tr><td align='left'>5.5</td><td align='left'> 1.2490</td><td align='left'> 29.9</td><td align='left'> 15.5</td><td align='left'> 1.2230</td><td align='left'> 27.3</td></tr>
+<tr><td align='left'>6.0</td><td align='left'> 1.2480</td><td align='left'> 29.8</td><td align='left'> 16.0</td><td align='left'> 1.2217</td><td align='left'> 27.2</td></tr>
+<tr><td align='left'>6.5</td><td align='left'> 1.2465</td><td align='left'> 29.7</td><td align='left'> 16.5</td><td align='left'> 1.2202</td><td align='left'> 27.0</td></tr>
+<tr><td align='left'>7.0</td><td align='left'> 1.2455</td><td align='left'> 29.6</td><td align='left'> 17.0</td><td align='left'> 1.2190</td><td align='left'> 26.9</td></tr>
+<tr><td align='left'>7.5</td><td align='left'> 1.2440</td><td align='left'> 29.5</td><td align='left'> 17.5</td><td align='left'> 1.2177</td><td align='left'> 26.8</td></tr>
+<tr><td align='left'>8.0</td><td align='left'> 1.2427</td><td align='left'> 29.3</td><td align='left'> 18.0</td><td align='left'> 1.2165</td><td align='left'> 26.7</td></tr>
+<tr><td align='left'>8.5</td><td align='left'> 1.2412</td><td align='left'> 29.2</td><td align='left'> 18.5</td><td align='left'> 1.2150</td><td align='left'> 26.5</td></tr>
+<tr><td align='left'>9.0</td><td align='left'> 1.2400</td><td align='left'> 29.0</td><td align='left'> 19.0</td><td align='left'> 1.2137</td><td align='left'> 26.4</td></tr>
+<tr><td align='left'>9.5</td><td align='left'> 1.2390</td><td align='left'> 28.9</td><td align='left'> 19.5</td><td align='left'> 1.2125</td><td align='left'> 26.3</td></tr>
+<tr><td align='left'>10.0</td><td align='left'> 1.2375</td><td align='left'> 28.8</td><td align='left'> 20.0</td><td align='left'> 1.2112</td><td align='left'> 26.2</td></tr>
+<tr><td align='left'>10.5</td><td align='left'> 1.2362</td><td align='left'> 28.7</td><td align='left'> 20.5</td><td align='left'> 1.2100</td><td align='left'> 26.0</td></tr>
+<tr><td align='left'>11.0</td><td align='left'> 1.2350</td><td align='left'> 28.6</td><td align='left'> 21.0</td><td align='left'> 1.2085</td><td align='left'> 25.9</td></tr>
+<tr><td align='left'>11.5</td><td align='left'> 1.2335</td><td align='left'> 28.4</td><td align='left'> &nbsp;</td><td align='left'> &nbsp;</td><td align='left'>&nbsp;</td></tr>
+</table></div>
+<p><span class='pagenum'><a name="Page_239" id="Page_239">[Pg 239]</a></span></p>
+
+
+
+<hr style="width: 65%;" />
+<h2>INDEX</h2>
+
+
+<p>
+A<br />
+<br />
+Acetin process for the determination of glycerol, <a href='#Page_155'>155</a>.<br />
+<br />
+Acid, Clupanodonic, <a href='#Page_20'>20</a>.<br />
+<br />
+Acid, Hydrochloric, <a href='#Page_111'>111</a>.<br />
+<br />
+Acid, Lauric, <a href='#Page_2'>2</a>.<br />
+<br />
+Acid, Myristic, <a href='#Page_2'>2</a>.<br />
+<br />
+Acid, Napthenic, <a href='#Page_24'>24</a>.<br />
+<br />
+Acid, Oleic, <a href='#Page_15'>15</a>, <a href='#Page_19'>19</a>.<br />
+<br />
+Acid, Palmitic, <a href='#Page_2'>2</a>.<br />
+<br />
+Acid, Pinic, <a href='#Page_22'>22</a>.<br />
+<br />
+Acid, Resin, <a href='#Page_144'>144</a>.<br />
+<br />
+Acid, Stearic, <a href='#Page_15'>15</a>, <a href='#Page_19'>19</a>.<br />
+<br />
+Acid, Sulfuric, <a href='#Page_112'>112</a>.<br />
+<br />
+Acid, Sylvic, <a href='#Page_22'>22</a>.<br />
+<br />
+Acid saponification, <a href='#Page_120'>120</a>.<br />
+<br />
+Air bleaching of palm oil, <a href='#Page_12'>12</a>.<br />
+<br />
+Albuminous matter, Removal from tallow, <a href='#Page_6'>6</a>.<br />
+<br />
+Alcohol, Denatured, <a href='#Page_82'>82</a>.<br />
+<br />
+Alcoholic method for free alkali in soap, <a href='#Page_139'>139</a>.<br />
+<br />
+Alkali Blue <a href='#Page_6'>6</a> B, indicator, <a href='#Page_129'>129</a>.<br />
+<br />
+Alkali, Total, determination of in soap, <a href='#Page_147'>147</a>.<br />
+<br />
+Alkalis, <a href='#Page_25'>25</a>.<br />
+<br />
+Alkalis used in soap making,<br />
+<span style="margin-left: 1em;">Testing of, <a href='#Page_134'>134</a>.</span><br />
+<br />
+Amalgamator, <a href='#Page_33'>33</a>.<br />
+<br />
+Analysis, Glycerine, International, <a href='#Page_150'>150</a>.<br />
+<br />
+Analysis, Soap, <a href='#Page_137'>137</a>.<br />
+<br />
+Analysis, Standard methods for fats and oils, <a href='#Page_165'>165</a>-196.<br />
+<br />
+Aqueous saponification, <a href='#Page_121'>121</a>.<br />
+<br />
+Arachis oil, <a href='#Page_79'>79</a>.<br />
+<br />
+Autoclave saponification, <a href='#Page_118'>118</a>.<br />
+<br />
+Automobile soaps, <a href='#Page_41'>41</a>.<br />
+<br />
+<br />
+B<br />
+<br />
+Barrels, sampling, <a href='#Page_168'>168</a>.<br />
+<br />
+Baum&eacute; scale, <a href='#Page_25'>25</a>.<br />
+<br />
+Bayberry wax, Use in shaving soap, <a href='#Page_89'>89</a>.<br />
+<br />
+Bichromate Process for glycerol determination, <a href='#Page_160'>160</a>.<br />
+<br />
+Bleaching, Fullers' earth process for tallow, <a href='#Page_4'>4</a>.<br />
+<br />
+Bleaching palm oil by bichromate method, <a href='#Page_9'>9</a>.<br />
+<br />
+Bleaching palm oil by air, <a href='#Page_12'>12</a>.<br />
+<br />
+Bosshard &amp; Huggenberg method for determination of free alkali, <a href='#Page_140'>140</a>.<br />
+<br />
+Bunching of soap, <a href='#Page_52'>52</a>.<br />
+<br />
+<br />
+C<br />
+<br />
+Candelite, <a href='#Page_96'>96</a>.<br />
+<br />
+Candle tar, <a href='#Page_125'>125</a>.<br />
+<br />
+Carbolic soap, <a href='#Page_77'>77</a>.<br />
+<br />
+Carbon Dioxide, Formation of in carbonate saponification, <a href='#Page_45'>45</a>.<br />
+<br />
+Carbonate, potassium, <a href='#Page_29'>29</a>.<br />
+<br />
+Carbonate, saponification, <a href='#Page_35'>35</a>, <a href='#Page_45'>45</a>.<br />
+<br />
+Carbonate, sodium, <a href='#Page_28'>28</a>.<br />
+<br />
+Castile soap, <a href='#Page_79'>79</a>.<br />
+<br />
+Castor oil ferment, <a href='#Page_121'>121</a>.<br />
+<br />
+Castor oil, Use of in transparent soaps, <a href='#Page_83'>83</a>.<br />
+<br />
+Caustic potash, <a href='#Page_26'>26</a>.<br />
+<br />
+Caustic potash, Electrolytic, <a href='#Page_27'>27</a>.<br />
+<br />
+Caustic soda, <a href='#Page_26'>26</a>.<br />
+<br />
+Changes in soap-making, <a href='#Page_36'>36</a>.<br />
+<br />
+Chemist, Importance of, <a href='#Page_127'>127</a>.<br />
+<br />
+Chipper, Soap, <a href='#Page_32'>32</a>.<br />
+<br />
+Chip soap, <a href='#Page_54'>54</a>.<br />
+<br />
+Chip soap, Cold made, <a href='#Page_55'>55</a>.<br />
+<br />
+Chip soap, Unfilled, <a href='#Page_56'>56</a>.<br />
+<br />
+Chrome bleaching of palm oil, <a href='#Page_9'>9</a>.<br />
+<br />
+Cloud test for oil, Standard method, <a href='#Page_182'>182</a>-183.<br />
+<br />
+Clupanodonic acid, <a href='#Page_20'>20</a>.<br />
+<br />
+Cocoanut oil, <a href='#Page_6'>6</a>.<br />
+<br />
+Cold cream soap, <a href='#Page_78'>78</a>.<br />
+<br />
+Cold made chip soaps, <a href='#Page_55'>55</a>.<br />
+<br />
+Cold made toilet soaps, <a href='#Page_72'>72</a>.<br />
+<br />
+Cold made transparent soaps, <a href='#Page_84'>84</a>.<br />
+<br />
+Cold process, <a href='#Page_35'>35</a>, <a href='#Page_43'>43</a>.<br />
+<br />
+Colophony, <a href='#Page_22'>22</a>.<br />
+<br />
+Coloring soap, <a href='#Page_75'>75</a>.<br />
+<br />
+Copra, <a href='#Page_7'>7</a>.<br />
+<br />
+Corn oil, <a href='#Page_14'>14</a>.<br />
+<br />
+Corrosive sublimate, <a href='#Page_78'>78</a>.<br />
+<br />
+Cotton goods. Soaps used for, <a href='#Page_103'>103</a>.<br />
+<br />
+Cottonseed oil, <a href='#Page_14'>14</a>.<br />
+<br />
+Cream, Shaving, <a href='#Page_90'>90</a>.<br />
+<br />
+Crude glycerine, <a href='#Page_113'>113</a>.<br />
+<br />
+Crutcher, <a href='#Page_32'>32</a>.<br />
+<br />
+Curd soap, <a href='#Page_71'>71</a>.<br />
+<br />
+<span class='pagenum'><a name="Page_240" id="Page_240">[Pg 240]</a></span>Cutting table, <a href='#Page_32'>32</a>.<br />
+<br />
+<br />
+D<br />
+<br />
+Determination of free fatty acid, <a href='#Page_128'>128</a>.<br />
+<br />
+Determination of unsaponifiable matter, <a href='#Page_132'>132</a>.<br />
+<br />
+Distillation of fatty acids, <a href='#Page_125'>125</a>.<br />
+<br />
+Drying machine, <a href='#Page_32'>32</a>.<br />
+<br />
+<br />
+E<br />
+<br />
+Enzymes, <a href='#Page_17'>17</a>.<br />
+<br />
+Eschweger soap, <a href='#Page_81'>81</a>.<br />
+<br />
+Examination of fats and oils, <a href='#Page_128'>128</a>.<br />
+<br />
+<br />
+F<br />
+<br />
+Fahrion's method for moisture, <a href='#Page_138'>138</a>.<br />
+<br />
+Fats and oils, Examination of, <a href='#Page_128'>128</a>.<br />
+<br />
+Fats and oils used in soap manufacture, <a href='#Page_3'>3</a>.<br />
+<br />
+Fatty acids, <a href='#Page_14'>14</a>.<br />
+<br />
+Fatty acids, Distillation of, <a href='#Page_125'>125</a>.<br />
+<br />
+Ferments, Splitting fats with, <a href='#Page_121'>121</a>.<br />
+<br />
+Fillers for laundry soaps, <a href='#Page_53'>53</a>.<br />
+<br />
+Fillers for soap powders, <a href='#Page_58'>58</a>.<br />
+<br />
+Finishing change, <a href='#Page_36'>36</a>.<br />
+<br />
+Fish oils, <a href='#Page_20'>20</a>.<br />
+<br />
+Floating soap, <a href='#Page_62'>62</a>.<br />
+<br />
+Formaldehyde soap, <a href='#Page_78'>78</a>.<br />
+<br />
+Frames, <a href='#Page_31'>31</a>.<br />
+<br />
+Free alkali in soap, Determination of, <a href='#Page_139'>139</a>.<br />
+<br />
+Free fatty acid, Determination of, <a href='#Page_128'>128</a>.<br />
+<br />
+Free fatty acids, Extraction from tallow, <a href='#Page_6'>6</a>.<br />
+<br />
+Free fatty acid, Standard method of dilu., <a href='#Page_174'>174</a>.<br />
+<span style="margin-left: 1em;">Note on method, <a href='#Page_188'>188</a>-189.</span><br />
+<br />
+Full boiled soaps, <a href='#Page_35'>35</a>.<br />
+<br />
+Fullers' earth bleaching of tallow, <a href='#Page_4'>4</a>.<br />
+<br />
+<br />
+G<br />
+<br />
+Glycerides, <a href='#Page_2'>2</a>.<br />
+<br />
+Glycerine, <a href='#Page_2'>2</a>.<br />
+<br />
+Glycerine analysis, <a href='#Page_150'>150</a>.<br />
+<br />
+Glycerine change, <a href='#Page_36'>36</a>.<br />
+<br />
+Glycerine, Crude, <a href='#Page_113'>113</a>.<br />
+<br />
+Glycerine in spent lyes, Recovery of, <a href='#Page_106'>106</a>.<br />
+<br />
+Glycerine in soap, Determination of, <a href='#Page_149'>149</a>.<br />
+<br />
+Glycerine, Sampling crude, <a href='#Page_162'>162</a>.<br />
+<br />
+Glycerine soaps, <a href='#Page_83'>83</a>.<br />
+<br />
+Glycerol content, Ways of calculating actual, <a href='#Page_159'>159</a>.<br />
+<br />
+Glycerol determination, Acetin process, <a href='#Page_155'>155</a>.<br />
+<br />
+Glycerol determination, Bichromate process for, <a href='#Page_160'>160</a>.<br />
+<br />
+Graining soap, <a href='#Page_30'>30</a>.<br />
+<br />
+Grease, <a href='#Page_21'>21</a>.<br />
+<br />
+Grease, Bleaching, <a href='#Page_21'>21</a>.<br />
+<br />
+Grinding soap, <a href='#Page_34'>34</a>.<br />
+<br />
+<br />
+H<br />
+<br />
+Hand Paste, <a href='#Page_93'>93</a>.<br />
+<br />
+Hard water, <a href='#Page_29'>29</a>.<br />
+<br />
+Hardened oils in toilet soap, Use of, <a href='#Page_96'>96</a>.<br />
+<br />
+Hydrocarbon oils, <a href='#Page_2'>2</a>.<br />
+<br />
+Hydrogenating oils, <a href='#Page_19'>19</a>.<br />
+<br />
+Hydrolysis of fats and oils, <a href='#Page_17'>17</a>.<br />
+<br />
+Hydrolytic dissociation of soap, <a href='#Page_1'>1</a>.<br />
+<br />
+Hydrometers, <a href='#Page_25'>25</a>.<br />
+<br />
+<br />
+I<br />
+<br />
+Indicators, Action, <a href='#Page_135'>135</a>-6.<br />
+<br />
+Insoluble impurities in fatty oils, Determination of (standard method) <a href='#Page_172'>172</a>.<br />
+<span style="margin-left: 1em;">Note on method <a href='#Page_187'>187</a>.</span><br />
+<br />
+Insoluble matter in soap, determination of, <a href='#Page_143'>143</a>.<br />
+<br />
+International committee on glycerine analysis, <a href='#Page_150'>150</a>.<br />
+<br />
+Iodine manufacturing oil, <a href='#Page_191'>191</a>.<br />
+<br />
+Iodine member Wijs method, Standard, <a href='#Page_177'>177</a>-181. Note on method, <a href='#Page_191'>191</a>.<br />
+<br />
+Iodine soap, <a href='#Page_78'>78</a>.<br />
+<br />
+<br />
+J<br />
+<br />
+Joslin, ref., <a href='#Page_113'>113</a>.<br />
+<br />
+<br />
+K<br />
+<br />
+"Killing" change, <a href='#Page_36'>36</a>.<br />
+<br />
+Koettstorfer number (Standard method), <a href='#Page_181'>181</a>-182.<br />
+<br />
+Kontakt reagent, <a href='#Page_117'>117</a>.<br />
+<br />
+Krebitz Process, <a href='#Page_123'>123</a>.<br />
+<br />
+Krutolin, <a href='#Page_96'>96</a>.<br />
+<br />
+<br />
+L<br />
+<br />
+Leiste &amp; Stiepel method for rosin in soap, <a href='#Page_146'>146</a>.<br />
+<br />
+<span class='pagenum'><a name="Page_241" id="Page_241">[Pg 241]</a></span>Liebermann, Storch reaction, <a href='#Page_144'>144</a>.<br />
+<br />
+Light powders, <a href='#Page_60'>60</a>.<br />
+<br />
+Laundry soap, <a href='#Page_48'>48</a>.<br />
+<br />
+LeBlanc Process, <a href='#Page_28'>28</a>.<br />
+<br />
+Lewkowitsch, ref., <a href='#Page_17'>17</a>, <a href='#Page_146'>146</a>.<br />
+<br />
+Lime saponification, <a href='#Page_118'>118</a>.<br />
+<br />
+Lime, Use in Krebitz Process, <a href='#Page_123'>123</a>.<br />
+<br />
+Lime, Use in treatment of glycerine water, <a href='#Page_116'>116</a>.<br />
+<br />
+Liquid medicinal soaps, <a href='#Page_79'>79</a>.<br />
+<br />
+Liquid soaps, <a href='#Page_94'>94</a>.<br />
+<br />
+Lyes, Spent, <a href='#Page_37'>37</a>.<br />
+<br />
+<br />
+M<br />
+<br />
+Magnesia, Use in  autoclave saponification, <a href='#Page_120'>120</a>.<br />
+<br />
+Manganese sulfate, Use of as catalyzer in fermentative cleavage of fats, <a href="#Page_122">122</a>.<br />
+<br />
+Marine soaps, <a href='#Page_39'>39</a>.<br />
+<br />
+Medicinal soaps, <a href='#Page_76'>76</a>.<br />
+<br />
+Medicinal soaps, Less important, <a href='#Page_78'>78</a>.<br />
+<br />
+Medicinal soaps, Therapeutic value of, <a href='#Page_76'>76</a>.<br />
+<br />
+Melting point of fat or oil, Standard method, <a href='#Page_193'>193</a>.<br />
+<br />
+Mercury soaps, <a href='#Page_78'>78</a>.<br />
+<br />
+Metallic soaps, <a href='#Page_1'>1</a>.<br />
+<br />
+Methyl orange, indicator, <a href='#Page_136'>136</a>.<br />
+<br />
+Meyerheim, ref., <a href='#Page_21'>21</a>.<br />
+<br />
+Mill soap, <a href='#Page_32'>32</a>.<br />
+<br />
+Moisture in soap, Determination of, <a href='#Page_138'>138</a>, <a href='#Page_130'>130</a>.<br />
+<br />
+Moisture and volatile matter in fats and oils, Standard method for detm. of, <a href='#Page_170'>170</a>.<br />
+<span style="margin-left: 1em;">Note on method, <a href='#Page_184'>184</a>-185.</span><br />
+<br />
+Mottle in soap, <a href='#Page_81'>81</a>.<br />
+<br />
+Mug shaving soap, <a href='#Page_90'>90</a>.<br />
+<br />
+<br />
+N<br />
+<br />
+Naphtha, Incorporation in soap, <a href='#Page_49'>49</a>.<br />
+<br />
+Naphthenic acids, <a href='#Page_24'>24</a>.<br />
+<br />
+Nigre, <a href='#Page_36'>36</a>.<br />
+<br />
+Normal acids, Equivalent in alkalis, <a href='#Page_136'>136</a>.<br />
+<br />
+<br />
+O<br />
+<br />
+Oils and fats, <a href='#Page_1'>1</a>.<br />
+<br />
+Oils and fats, Chemical constants, <a href='#Page_18'>18</a>.<br />
+<br />
+Oils and fats, Distinction, <a href='#Page_1'>1</a>.<br />
+<br />
+Oils and fats, Preserving, <a href='#Page_18'>18</a>.<br />
+<br />
+Oils and fat, Nature of used in soap manufacture, <a href='#Page_2'>2</a>.<br />
+<br />
+Oils and fats, Rancidity of, <a href='#Page_16'>16</a>.<br />
+<br />
+Oil hardening, <a href='#Page_19'>19</a>.<br />
+<br />
+Oleic acid, <a href='#Page_15'>15</a>, <a href='#Page_19'>19</a>.<br />
+<br />
+Olein, <a href='#Page_2'>2</a>, <a href='#Page_19'>19</a>.<br />
+<br />
+Olive oil, <a href='#Page_14'>14</a>.<br />
+<br />
+Olive oil foots, <a href='#Page_14'>14</a>.<br />
+<br />
+Organoleptic methods, <a href='#Page_127'>127</a>.<br />
+<br />
+<br />
+P<br />
+<br />
+Palmatin, <a href='#Page_2'>2</a>.<br />
+<br />
+Palm kernel oil, <a href='#Page_8'>8</a>.<br />
+<br />
+Palmitic acid, <a href='#Page_2'>2</a>.<br />
+<br />
+Palm oil, <a href='#Page_8'>8</a>.<br />
+<br />
+Palm oil, air bleaching, <a href='#Page_12'>12</a>.<br />
+<br />
+Palm oil, Chrome bleaching of, <a href='#Page_9'>9</a>.<br />
+<br />
+Palm oil soap, <a href='#Page_66'>66</a>.<br />
+<br />
+Pearl ash, <a href='#Page_29'>29</a>.<br />
+<br />
+Perfuming and coloring toilet soaps, <a href='#Page_73'>73</a>.<br />
+<br />
+Peroxide soap, <a href='#Page_78'>78</a>.<br />
+<br />
+Petroff reagent, <a href='#Page_117'>117</a>.<br />
+<br />
+Pfeilring reagent, <a href='#Page_117'>117</a>.<br />
+<br />
+Phenol, <a href='#Page_77'>77</a>.<br />
+<br />
+Phenolphthalein, indicator, <a href='#Page_38'>38</a>.<br />
+<br />
+Phenolphthalein, Using as indicator, <a href='#Page_51'>51</a>.<br />
+<br />
+Phenols, Soaps containing, <a href='#Page_77'>77</a>.<br />
+<br />
+Pinic acid, <a href='#Page_22'>22</a>.<br />
+<br />
+Plodder, <a href='#Page_33'>33</a>.<br />
+<br />
+Potash from wood ash, <a href='#Page_27'>27</a>.<br />
+<br />
+Potassium carbonate, <a href='#Page_29'>29</a>.<br />
+<br />
+Powders, Light, <a href='#Page_60'>60</a>.<br />
+<br />
+Powders, Scouring, <a href='#Page_61'>61</a>.<br />
+<br />
+Powders, Shaving, <a href='#Page_90'>90</a>.<br />
+<br />
+Powders, Soap, <a href='#Page_56'>56</a>.<br />
+<br />
+Precipitation test for treated spent lyes, <a href='#Page_110'>110</a>.<br />
+<br />
+Prevention of rancidity, <a href='#Page_18'>18</a>.<br />
+<br />
+Pumice or sand soaps, <a href='#Page_93'>93</a>.<br />
+<br />
+Purple shade in soap, <a href='#Page_75'>75</a>.<br />
+<br />
+<br />
+R<br />
+<br />
+Rancidity of oils and fats, <a href='#Page_16'>16</a>.<br />
+<br />
+Rancidity, Prevention, <a href='#Page_18'>18</a>.<br />
+<br />
+Recovery of glycerine from spent lye, <a href='#Page_106'>106</a>.<br />
+<br />
+Red oil, <a href='#Page_15'>15</a>.<br />
+<br />
+Red oil, Saponified, <a href='#Page_15'>15</a>.<br />
+<br />
+Resin acids, Total fatty and, Determination of in soap, <a href='#Page_144'>144</a>.<br />
+<br />
+Ribot, ref., <a href='#Page_20'>20</a>.<br />
+<br />
+<span class='pagenum'><a name="Page_242" id="Page_242">[Pg 242]</a></span>Rosin, <a href='#Page_22'>22</a>.<br />
+<br />
+Rosin, Determination of in soap, <a href='#Page_144'>144</a>.<br />
+<br />
+Rosin saponification, <a href='#Page_23'>23</a>.<br />
+<br />
+Run and glued up soaps, <a href='#Page_69'>69</a>.<br />
+<br />
+Run soaps, <a href='#Page_39'>39</a>.<br />
+<br />
+<br />
+S<br />
+<br />
+Sal soda, <a href='#Page_29'>29</a>.<br />
+<br />
+Salt, <a href='#Page_30'>30</a>.<br />
+<br />
+Salting out, <a href='#Page_30'>30</a>.<br />
+<br />
+Salt "pickle," <a href='#Page_37'>37</a>.<br />
+<br />
+Sampling crude glycerine, <a href='#Page_162'>162</a>.<br />
+<br />
+Sampling for standard method, <a href='#Page_166'>166</a>. Note on, <a href='#Page_184'>184</a>.<br />
+<br />
+Sampling oils and fats, <a href='#Page_128'>128</a>.<br />
+<br />
+Sampling soap, <a href='#Page_137'>137</a>.<br />
+<br />
+Saponification by ferments, <a href='#Page_121'>121</a>.<br />
+<br />
+Saponification, Acid, <a href='#Page_120'>120</a>.<br />
+<br />
+Saponification, Aqueous, <a href='#Page_121'>121</a>.<br />
+<br />
+Saponification, Autoclave, <a href='#Page_118'>118</a>.<br />
+<br />
+Saponification, Carbonate, <a href='#Page_45'>45</a>.<br />
+<br />
+Saponification defined, <a href='#Page_2'>2</a>, <a href='#Page_105'>105</a>.<br />
+<br />
+Saponification, Lime, <a href='#Page_118'>118</a>.<br />
+<br />
+Saponification number, <a href='#Page_181'>181</a>-182.<br />
+<br />
+Saponification, Rosin, <a href='#Page_23'>23</a>.<br />
+<br />
+Saponification, Various methods, <a href='#Page_105'>105</a>.<br />
+<br />
+Scouring and fulling soaps for wool, <a href='#Page_98'>98</a>.<br />
+<br />
+Scouring powders, <a href='#Page_61'>61</a>.<br />
+<br />
+Scouring soap, <a href='#Page_61'>61</a>.<br />
+<br />
+Semi-boiled laundry soaps, <a href='#Page_49'>49</a>.<br />
+<br />
+Semi-boiled process, <a href='#Page_44'>44</a>.<br />
+<br />
+Shaving cream, <a href='#Page_90'>90</a>.<br />
+<br />
+Shaving powder, <a href='#Page_90'>90</a>.<br />
+<br />
+Shaving soaps, <a href='#Page_87'>87</a>.<br />
+<br />
+Silica and silicates, Determination of in soap, <a href='#Page_148'>148</a>.<br />
+<br />
+Silk dyeing, <a href='#Page_102'>102</a>.<br />
+<br />
+Silk industry, Soaps used in, <a href='#Page_101'>101</a>.<br />
+<br />
+Slabber, <a href='#Page_32'>32</a>.<br />
+<br />
+Smith method for moisture in soap, <a href='#Page_138'>138</a>.<br />
+<br />
+Soap analysis, <a href='#Page_137'>137</a>.<br />
+<br />
+Soap, Automobile, <a href='#Page_41'>41</a>.<br />
+<br />
+Soap, Carbolic, <a href='#Page_71'>71</a>.<br />
+<br />
+Soap, Castile, <a href='#Page_79'>79</a>.<br />
+<br />
+Soap, Chip, <a href='#Page_54'>54</a>.<br />
+<br />
+Soap Chip, cold made, <a href='#Page_55'>55</a>.<br />
+<br />
+Soap, Chip, unfilled, <a href='#Page_56'>56</a>.<br />
+<br />
+Soap, Cold cream, <a href='#Page_78'>78</a>.<br />
+<br />
+Soap, Coloring, <a href='#Page_75'>75</a>.<br />
+<br />
+Soap containing phenols, <a href='#Page_77'>77</a>.<br />
+<br />
+Soap, Curd, <a href='#Page_71'>71</a>.<br />
+<br />
+Soap, Defined, <a href='#Page_1'>1</a>.<br />
+<br />
+Soap, Determination insoluble matter, <a href='#Page_143'>143</a>.<br />
+<br />
+Soap, Determining glycerine in, <a href='#Page_149'>149</a>.<br />
+<br />
+Soap, Eschweger, <a href='#Page_81'>81</a>.<br />
+<br />
+Soap, Floating, <a href='#Page_62'>62</a>.<br />
+<br />
+Soap, Formaldehyde, <a href='#Page_78'>78</a>.<br />
+<br />
+Soap for wool, Scouring and fulling, <a href='#Page_98'>98</a>.<br />
+<br />
+Soap, Full boiled, <a href='#Page_35'>35</a>.<br />
+<br />
+Soap, Iodine, <a href='#Page_78'>78</a>.<br />
+<br />
+Soap kettle, <a href='#Page_31'>31</a>.<br />
+<br />
+Soap, Laundry, <a href='#Page_48'>48</a>.<br />
+<br />
+Soap, Liquid, <a href='#Page_94'>94</a>.<br />
+<br />
+Soap lye crude glycerine, <a href='#Page_113'>113</a>.<br />
+<br />
+Soap, Marine, <a href='#Page_39'>39</a>.<br />
+<br />
+Soap, Medicinal, <a href='#Page_76'>76</a>.<br />
+<br />
+Soap, Medicinal, less important, <a href='#Page_78'>78</a>.<br />
+<br />
+Soap, Mercury, <a href='#Page_78'>78</a>.<br />
+<br />
+Soap, Metallic, <a href='#Page_1'>1</a>.<br />
+<br />
+Soap, Peroxide, <a href='#Page_78'>78</a>.<br />
+<br />
+Soap powders, <a href='#Page_56'>56</a>.<br />
+<br />
+Soap, Pumice or sand, <a href='#Page_93'>93</a>.<br />
+<br />
+Soap, Rosin settled, <a href='#Page_50'>50</a>.<br />
+<br />
+Soap, Run and glued up, <a href='#Page_69'>69</a>.<br />
+<br />
+Soap, Scouring, <a href='#Page_61'>61</a>.<br />
+<br />
+Soap, Semi-boiled laundry, <a href='#Page_49'>49</a>.<br />
+<br />
+Soap, Shaving, <a href='#Page_87'>87</a>.<br />
+<br />
+Soap, Sulphur, <a href='#Page_77'>77</a>.<br />
+<br />
+Soap, Tannin, <a href='#Page_78'>78</a>.<br />
+<br />
+Soap, Tar, <a href='#Page_77'>77</a>.<br />
+<br />
+Soap, Test for color of, <a href='#Page_133'>133</a>.<br />
+<br />
+Soap, Textile, <a href='#Page_98'>98</a>.<br />
+<br />
+Soap, Toilet, <a href='#Page_65'>65</a>.<br />
+<br />
+Soap, Toilet cheaper, <a href='#Page_68'>68</a>.<br />
+<br />
+Soap, Toilet, cold made, <a href='#Page_72'>72</a>.<br />
+<br />
+Soap, Toilet perfuming and coloring, <a href='#Page_73'>73</a>.<br />
+<br />
+Soap, Transparent, <a href='#Page_82'>82</a>.<br />
+<br />
+Soap, Transparent, cold made, <a href='#Page_84'>84</a>.<br />
+<br />
+Soap used for cotton goods, <a href='#Page_103'>103</a>.<br />
+<br />
+Soap used in the silk industry, <a href='#Page_101'>101</a>.<br />
+<br />
+Soap, Witch hazel, <a href='#Page_78'>78</a>.<br />
+<br />
+Soap, Wool thrower's, <a href='#Page_100'>100</a>.<br />
+<br />
+Soap, Worsted finishing, <a href='#Page_101'>101</a>.<br />
+<br />
+Soda ash, <a href='#Page_28'>28</a>.<br />
+<br />
+Sodium carbonate, <a href='#Page_28'>28</a>.<br />
+<br />
+Sodium perborate, Use of in soap powders, <a href='#Page_57'>57</a>.<br />
+<br />
+Soft soaps, <a href='#Page_40'>40</a>.<br />
+<br />
+Soluble mineral matter detm. of in fats and oils, <a href='#Page_173'>173</a>.<br />
+<span class='pagenum'><a name="Page_243" id="Page_243">[Pg 243]</a></span><span style="margin-left: 1em;">Note on method, <a href='#Page_187'>187</a>-188.</span><br />
+<br />
+Solvay process, <a href='#Page_28'>28</a>.<br />
+<br />
+Soya bean oil, <a href='#Page_14'>14</a>.<br />
+<br />
+Spent lye, Recovery of glycerine from, <a href='#Page_106'>106</a>.<br />
+<br />
+Spent lyes, <a href='#Page_37'>37</a>.<br />
+<br />
+Spent lyes, Treatment of for glycerine recovery, <a href='#Page_107'>107</a>.<br />
+<br />
+Splitting fats with ferments, <a href='#Page_121'>121</a>.<br />
+<br />
+Standard methods of analysis for fats and oils, <a href='#Page_165'>165</a>-196.<br />
+<br />
+Starch and gelatine, Determination in soap, <a href='#Page_143'>143</a>.<br />
+<br />
+Stearic acid, <a href='#Page_15'>15</a>, <a href='#Page_19'>19</a>.<br />
+<br />
+Stearin, <a href='#Page_2'>2</a>, <a href='#Page_19'>19</a>.<br />
+<br />
+Strengthening change, <a href='#Page_36'>36</a>.<br />
+<br />
+Strengthening lyes, <a href='#Page_38'>38</a>.<br />
+<br />
+Strunz crutcher, <a href='#Page_63'>63</a>.<br />
+<br />
+Sugar in soap, Determination of, <a href='#Page_150'>150</a>.<br />
+<br />
+Sugar, Use in transparent soap, <a href='#Page_83'>83</a>.<br />
+<br />
+Sulfate of alumina, Use of in spent lyes, <a href='#Page_108'>108</a>.<br />
+<br />
+Sulphonated oils, <a href='#Page_104'>104</a>.<br />
+<br />
+Sulphur soaps, <a href='#Page_77'>77</a>.<br />
+<br />
+Sweating of soap, <a href='#Page_62'>62</a>.<br />
+<br />
+Sweet water, <a href='#Page_119'>119</a>.<br />
+<br />
+Sylvic acid, <a href='#Page_22'>22</a>.<br />
+<br />
+<br />
+T<br />
+<br />
+Talgol, <a href='#Page_96'>96</a>.<br />
+<br />
+Tallow, <a href='#Page_4'>4</a>.<br />
+<br />
+Tallow, Fullers' earth bleaching of, <a href='#Page_4'>4</a>.<br />
+<br />
+Tallow, Improving color by extraction of free fatty acid, <a href='#Page_6'>6</a>.<br />
+<br />
+Tannin soap, <a href='#Page_78'>78</a>.<br />
+<br />
+Tar soap, <a href='#Page_77'>77</a>.<br />
+<br />
+Test for color of soap, <a href='#Page_133'>133</a>.<br />
+<br />
+Testing of alkalis used in soap making, <a href='#Page_134'>134</a>.<br />
+<br />
+Textile soaps, <a href='#Page_98'>98</a>.<br />
+<br />
+Titer, <a href='#Page_130'>130</a>.<br />
+<br />
+Tank cars, Sampling, <a href='#Page_166'>166</a>.<br />
+<br />
+Tierces, Sampling, <a href='#Page_168'>168</a>.<br />
+<br />
+Titer, Standard method, <a href='#Page_175'>175</a>.<br />
+<br />
+Titer, Note on, <a href='#Page_189'>189</a>.<br />
+<br />
+Tung oil, Note one iodine, number of, <a href='#Page_180'>180</a>.<br />
+<br />
+Toilet soap, <a href='#Page_65'>65</a>.<br />
+<br />
+Toilet soaps, Cheaper, <a href='#Page_68'>68</a>.<br />
+<br />
+Toilet soap, Use of hardened oils in, <a href='#Page_96'>96</a>.<br />
+<br />
+Total alkali, Determination of in soap, <a href='#Page_147'>147</a>.<br />
+<br />
+Total fatty and resin acids, Determination of in soap, <a href='#Page_144'>144</a>.<br />
+<br />
+Train oils, <a href='#Page_20'>20</a>.<br />
+<br />
+Transparent soap, <a href='#Page_82'>82</a>.<br />
+<br />
+Transparent soap, Cold made, <a href='#Page_84'>84</a>.<br />
+<br />
+Troweling soap, <a href='#Page_52'>52</a>.<br />
+<br />
+Tsujimoto, ref., <a href='#Page_20'>20</a>.<br />
+<br />
+Tubes for transparent soap, <a href='#Page_85'>85</a>.<br />
+<br />
+Turkey red oil, <a href='#Page_104'>104</a>.<br />
+<br />
+Twaddle scale, <a href='#Page_25'>25</a>.<br />
+<br />
+Twitchell method for rosin, <a href='#Page_145'>145</a>.<br />
+<br />
+Twitchell process, <a href='#Page_113'>113</a>.<br />
+<br />
+Twitchell process, Advantages, <a href='#Page_113'>113</a>.<br />
+<br />
+<br />
+U<br />
+<br />
+Unsaponifiable matter, Determination of in oils and fats, <a href='#Page_132'>132</a>.<br />
+<br />
+Unsaponifiable matter, Determination of in soap, <a href='#Page_148'>148</a>.<br />
+<br />
+Unsaponifiable matter, determination of by standard method, <a href='#Page_176'>176</a>.<br />
+<br />
+<br />
+V<br />
+<br />
+Vacuum Oven, Standard, <a href='#Page_176'>176</a>.<br />
+<br />
+Vegetable oils, <a href='#Page_6'>6</a>.<br />
+<br />
+<br />
+W<br />
+<br />
+Water, <a href='#Page_29'>29</a>.<br />
+<br />
+Water, Hard, <a href='#Page_29'>29</a>.<br />
+<br />
+Witch hazel soap, <a href='#Page_78'>78</a>.<br />
+<br />
+Wool thrower's soap, <a href='#Page_100'>100</a>.<br />
+<br />
+Worsted finishing soaps, <a href='#Page_101'>101</a>.<br />
+<br />
+<br />
+Z<br />
+<br />
+Zinc oxide, Use of in autoclave saponification, <a href='#Page_120'>120</a>.<br />
+<br />
+Zinc oxide, Use of in soap, <a href='#Page_33'>33</a>.<br />
+</p>
+
+
+
+<hr style="width: 65%;" />
+<h2>LITERATURE OF THE CHEMICAL INDUSTRIES</h2>
+
+
+<p>On our shelves is the most complete stock of technical, industrial,
+engineering and scientific books in the United States. The technical
+literature of every trade is well represented, as is also the literature
+relating to the various sciences, both the books useful for reference as
+well as those fitted for students' use as textbooks.</p>
+
+<p>A large number of these we publish and for an ever increasing number we
+are the sole agents.</p>
+
+<p>ALL INQUIRIES MADE OF US ARE CHEERFULLY AND CAREFULLY ANSWERED AND
+COMPLETE CATALOGS AS WELL AS SPECIAL LISTS SENT FREE ON REQUEST</p>
+
+<div class="figcenter" style="width: 150px;">
+<img src="images/title.jpg" width="150" height="130" alt="" title="" />
+</div>
+
+<p>D. VAN NOSTRAND COMPANY</p>
+
+<p><i>Publishers and Booksellers</i></p>
+
+<p>8 WARREN STREET NEW YORK</p>
+
+
+<h3>The Soap-Maker's Book Shelf</h3>
+
+<p>A list of standard books relating to soapmaking and allied industries.</p>
+
+<p class="center">Published and For Sale by<br />
+
+D. VAN NOSTRAND COMPANY<br />
+
+<i>Publishers and Booksellers</i><br />
+
+
+8 WARREN STREET&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; NEW YORK
+</p>
+
+
+<p><b>Askinson, George W.</b> Perfumes and Cosmetics. Their preparation and
+manufacture. Fourth Edition, translated from the German, and revised
+with additions by W. L. Dudley. 32 illustrations. 6-1/4 &times; 9-1/2. Cloth.
+354 pp. New York, 1915. <b>$5.00</b></p>
+
+<p><b>Chalmers, T. W.</b> The Production and Treatment of Vegetable Oils.
+Including chapters on the refining of oils, the hydrogenation of oils,
+the generation of hydrogen, soap making, the recovery and refining of
+glycerine, and the splitting of oils. 95 illustrations, 9 folding
+plates. 8 &times; 11-1/2. Cloth. 163 pp. London, 1919. <b>$7.50</b></p>
+
+<p><b>Deite, C.</b> Manual of Toilet Soap-Making. Comprising toilet soaps,
+medicated soaps, and other specialties. Second Revised Edition. 85
+illustrations. 6-1/2 &times; 10. Cloth. 356 pp. London, 1920. <b>$7.50</b></p>
+
+<p><b>Ellis, Carleton G.</b> The Hydrogenation of Oils, Catalyzers and Catalysis
+and the Generation of Hydrogen and Oxygen. Second Edition, thoroughly
+revised and enlarged. 240 illustrations. 6-1/4 &times; 9-1/2. Cloth. 767 pp.
+N. Y., 1919. <b>$7.50</b></p>
+
+<p><b>Fischer, M. H.</b> Soaps and Proteins, Their Colloid Chemistry in Theory and
+Practice. With the collaboration of G. D. McLaughlin and M. O. Hooker.
+114 illustrations. 6 &times; 9-1/4. Cloth. 281 pp. New York, 1921. <b>$4.00</b></p>
+
+<p><b>Holde, D.</b> The Examination of Hydrocarbon Oils, and of the Saponifiable
+Fats and Waxes. Translated from the Fourth German Edition by Edward
+Mueller. 115 illustrations. 6-1/4 &times; 9-1/4. Cloth. 499 pp. N. Y., 1915.
+<b>Net, $5.00</b></p>
+
+<p><b>Hurst, G. H</b>. Soaps. A practical manual of the manufacture of domestic,
+toilet and other soaps. Second Edition. 66 illustrations. 6 &times; 8-3/4.
+Cloth. 385 pp. London, 1907. <b>$6.00</b></p>
+
+<p><b>Hurst, George H., and Simmons, W. H.</b> Textile Soaps and Oils. A handbook
+on the preparation, properties, and analysis of the soaps and oils and
+in textile manufacturing, dyeing and printing. Third Edition, revised.
+12 illustrations. 5-1/2 &times; 8-3/4. Cloth. 212 pp. London, 1921. <b>$4.00</b></p>
+
+<p><b>Koller, T. Cosmetics.</b> A handbook of the manufacture, employment, and
+testing of all cosmetic materials and cosmetic specialties, with
+numerous recipes. Translated from the German. Third Edition. 5 &times; 7-1/2.
+Cloth. 264 pp. London, 1920. <b>$3.50</b></p>
+
+<p><b>Koppe, S. W. Glycerine.</b> Its introduction, Uses and Examination. For
+chemists, perfumers, soapmakers, pharmacists, and explosives
+technologists. 7 illustrations. 5-1/4 &times; 7-1/2. Cloth. 260 pp. New York,
+1915. <b>$3.50</b></p>
+
+<p><b>Lamborn, L. L.</b> Modern Soaps, Candles, and Glycerin. A practical manual
+of modern methods of utilization of fats and oils in the manufacture of
+soaps and candles, and the recovery of glycerin. 228 illustrations.
+6-1/2 &times; 9-1/4. Cloth. 708 pp. N. Y., 1906. <b>$10.00</b></p>
+
+<p><b>Murray, B. L.</b> Standards and Tests for Reagent Chemicals. 6 &times; 9. Cloth.
+400 pp. New York, 1920. <b>$3.00</b></p>
+
+<p><b>Parry, Ernest J.</b> The Chemistry of Essential Oils and Artificial
+Perfumes. Vol. I, Monographs on Essential Oils. Fourth Edition, revised
+and enlarged. 51 illustrations. 6-1/4 &times; 10. Cloth. 557 pp. London, 1921.
+<b>$9.00</b></p>
+
+<p>Vol. II. Constituents of Essential Oils, Synthetic Perfumes and Isolated
+Aromatics, and the Analysis of Essential Oils. Third Edition, revised
+and enlarged. Illustrated. 351 pp. London, 1919. <b>$7.00</b></p>
+
+<p><b>Partington, J. R.</b> The Alkali Industry. 63 illustrations. 5-1/2 &times; 8-1/2.
+Cloth. 318 pp. London, 1918. <b>$3.00</b></p>
+
+<p><b>Rogers, Allen.</b> Industrial Chemistry. A manual for the student and
+manufacturer. Third Edition, thoroughly revised and enlarged. 377
+illustrations. 6-1/2 &times; 9-3/4. Flexible fabrikoid. 1255 pp. New York,
+1920. <b>$7.50</b></p>
+
+<p><b>Scott, Wilfred W.</b> (Editor). Standard Methods of Chemical Analysis. A
+manual of analytical methods and general reference for the analytical
+chemist and for the advanced student. Second Edition, revised, with
+additional tables. 142 illustrations, 3 color plates. 7 &times; 9-1/4. Cloth.
+900 pp. N. Y., 1917. <b>$7.50</b></p>
+
+<p><b>Simmons, W. H.</b> Fats, Waxes and Essential Oils. <b>In Press.</b></p>
+
+<p><b>Simmons, William H.</b> Soap. Its composition, manufacture and properties.
+11 illustrations. 4-3/4 &times; 7-1/4. Cloth. 133 pp. London, 1916. <b>$1.00</b></p>
+
+<p><b>Simmons, W. H., and Appleton, H. A.</b> The Handbook of Soap Manufacture. 27
+illustrations. 6 &times; 9. Cloth. 166 pp. London, 1908. <b>$4.00</b></p>
+
+<p><b>Van Nostrand's Chemical Annual.</b> Edited by John C. Olsen. A handbook of
+useful data for analytical manufacturing and investigating chemists and
+chemical students. Fourth Issue, enlarged. 5 &times; 7-1/2. Flexible
+fabrikoid. 785 pp. New York, 1918. <b>$3.00</b></p>
+
+<p><b>Watt, A.</b> Art of Soapmaking. A practical handbook of the manufacture of
+hard and soft soaps, toilet soaps, etc. Seventh Edition, revised and
+enlarged. 43 illustrations. 5-1/4 &times; 7-1/2. Cloth. 323 pp. London, 1918.
+<b>$4.00</b></p>
+
+<p><b>Wright, C. R. A.</b> Animal and Vegetable Fixed Oils, Fats, Butters, and
+Waxes: Their Preparation and Properties, and the Manufacture Therefrom
+of Candles, Soaps, and Other Products. Third Edition, revised and
+greatly enlarged by C. Ainsworth Mitchell. 185 illustrations, 3 plates.
+6 &times; 9. Cloth. 953 pp. London, 1921. <b>$16.50</b></p>
+
+
+
+
+
+
+
+
+
+<pre>
+
+
+
+
+
+End of the Project Gutenberg EBook of Soap-Making Manual, by E. G. Thomssen
+
+*** END OF THIS PROJECT GUTENBERG EBOOK SOAP-MAKING MANUAL ***
+
+***** This file should be named 34114-h.htm or 34114-h.zip *****
+This and all associated files of various formats will be found in:
+        https://www.gutenberg.org/3/4/1/1/34114/
+
+Produced by David Clarke, Josephine Paolucci and the Online
+Distributed Proofreading Team at https://www.pgdp.net. (This
+file was produced from images generously made available
+by The Internet Archive/American Libraries.)
+
+
+Updated editions will replace the previous one--the old editions
+will be renamed.
+
+Creating the works from public domain print editions means that no
+one owns a United States copyright in these works, so the Foundation
+(and you!) can copy and distribute it in the United States without
+permission and without paying copyright royalties.  Special rules,
+set forth in the General Terms of Use part of this license, apply to
+copying and distributing Project Gutenberg-tm electronic works to
+protect the PROJECT GUTENBERG-tm concept and trademark.  Project
+Gutenberg is a registered trademark, and may not be used if you
+charge for the eBooks, unless you receive specific permission.  If you
+do not charge anything for copies of this eBook, complying with the
+rules is very easy.  You may use this eBook for nearly any purpose
+such as creation of derivative works, reports, performances and
+research.  They may be modified and printed and given away--you may do
+practically ANYTHING with public domain eBooks.  Redistribution is
+subject to the trademark license, especially commercial
+redistribution.
+
+
+
+*** START: FULL LICENSE ***
+
+THE FULL PROJECT GUTENBERG LICENSE
+PLEASE READ THIS BEFORE YOU DISTRIBUTE OR USE THIS WORK
+
+To protect the Project Gutenberg-tm mission of promoting the free
+distribution of electronic works, by using or distributing this work
+(or any other work associated in any way with the phrase "Project
+Gutenberg"), you agree to comply with all the terms of the Full Project
+Gutenberg-tm License (available with this file or online at
+https://gutenberg.org/license).
+
+
+Section 1.  General Terms of Use and Redistributing Project Gutenberg-tm
+electronic works
+
+1.A.  By reading or using any part of this Project Gutenberg-tm
+electronic work, you indicate that you have read, understand, agree to
+and accept all the terms of this license and intellectual property
+(trademark/copyright) agreement.  If you do not agree to abide by all
+the terms of this agreement, you must cease using and return or destroy
+all copies of Project Gutenberg-tm electronic works in your possession.
+If you paid a fee for obtaining a copy of or access to a Project
+Gutenberg-tm electronic work and you do not agree to be bound by the
+terms of this agreement, you may obtain a refund from the person or
+entity to whom you paid the fee as set forth in paragraph 1.E.8.
+
+1.B.  "Project Gutenberg" is a registered trademark.  It may only be
+used on or associated in any way with an electronic work by people who
+agree to be bound by the terms of this agreement.  There are a few
+things that you can do with most Project Gutenberg-tm electronic works
+even without complying with the full terms of this agreement.  See
+paragraph 1.C below.  There are a lot of things you can do with Project
+Gutenberg-tm electronic works if you follow the terms of this agreement
+and help preserve free future access to Project Gutenberg-tm electronic
+works.  See paragraph 1.E below.
+
+1.C.  The Project Gutenberg Literary Archive Foundation ("the Foundation"
+or PGLAF), owns a compilation copyright in the collection of Project
+Gutenberg-tm electronic works.  Nearly all the individual works in the
+collection are in the public domain in the United States.  If an
+individual work is in the public domain in the United States and you are
+located in the United States, we do not claim a right to prevent you from
+copying, distributing, performing, displaying or creating derivative
+works based on the work as long as all references to Project Gutenberg
+are removed.  Of course, we hope that you will support the Project
+Gutenberg-tm mission of promoting free access to electronic works by
+freely sharing Project Gutenberg-tm works in compliance with the terms of
+this agreement for keeping the Project Gutenberg-tm name associated with
+the work.  You can easily comply with the terms of this agreement by
+keeping this work in the same format with its attached full Project
+Gutenberg-tm License when you share it without charge with others.
+
+1.D.  The copyright laws of the place where you are located also govern
+what you can do with this work.  Copyright laws in most countries are in
+a constant state of change.  If you are outside the United States, check
+the laws of your country in addition to the terms of this agreement
+before downloading, copying, displaying, performing, distributing or
+creating derivative works based on this work or any other Project
+Gutenberg-tm work.  The Foundation makes no representations concerning
+the copyright status of any work in any country outside the United
+States.
+
+1.E.  Unless you have removed all references to Project Gutenberg:
+
+1.E.1.  The following sentence, with active links to, or other immediate
+access to, the full Project Gutenberg-tm License must appear prominently
+whenever any copy of a Project Gutenberg-tm work (any work on which the
+phrase "Project Gutenberg" appears, or with which the phrase "Project
+Gutenberg" is associated) is accessed, displayed, performed, viewed,
+copied or distributed:
+
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever.  You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at www.gutenberg.org
+
+1.E.2.  If an individual Project Gutenberg-tm electronic work is derived
+from the public domain (does not contain a notice indicating that it is
+posted with permission of the copyright holder), the work can be copied
+and distributed to anyone in the United States without paying any fees
+or charges.  If you are redistributing or providing access to a work
+with the phrase "Project Gutenberg" associated with or appearing on the
+work, you must comply either with the requirements of paragraphs 1.E.1
+through 1.E.7 or obtain permission for the use of the work and the
+Project Gutenberg-tm trademark as set forth in paragraphs 1.E.8 or
+1.E.9.
+
+1.E.3.  If an individual Project Gutenberg-tm electronic work is posted
+with the permission of the copyright holder, your use and distribution
+must comply with both paragraphs 1.E.1 through 1.E.7 and any additional
+terms imposed by the copyright holder.  Additional terms will be linked
+to the Project Gutenberg-tm License for all works posted with the
+permission of the copyright holder found at the beginning of this work.
+
+1.E.4.  Do not unlink or detach or remove the full Project Gutenberg-tm
+License terms from this work, or any files containing a part of this
+work or any other work associated with Project Gutenberg-tm.
+
+1.E.5.  Do not copy, display, perform, distribute or redistribute this
+electronic work, or any part of this electronic work, without
+prominently displaying the sentence set forth in paragraph 1.E.1 with
+active links or immediate access to the full terms of the Project
+Gutenberg-tm License.
+
+1.E.6.  You may convert to and distribute this work in any binary,
+compressed, marked up, nonproprietary or proprietary form, including any
+word processing or hypertext form.  However, if you provide access to or
+distribute copies of a Project Gutenberg-tm work in a format other than
+"Plain Vanilla ASCII" or other format used in the official version
+posted on the official Project Gutenberg-tm web site (www.gutenberg.org),
+you must, at no additional cost, fee or expense to the user, provide a
+copy, a means of exporting a copy, or a means of obtaining a copy upon
+request, of the work in its original "Plain Vanilla ASCII" or other
+form.  Any alternate format must include the full Project Gutenberg-tm
+License as specified in paragraph 1.E.1.
+
+1.E.7.  Do not charge a fee for access to, viewing, displaying,
+performing, copying or distributing any Project Gutenberg-tm works
+unless you comply with paragraph 1.E.8 or 1.E.9.
+
+1.E.8.  You may charge a reasonable fee for copies of or providing
+access to or distributing Project Gutenberg-tm electronic works provided
+that
+
+- You pay a royalty fee of 20% of the gross profits you derive from
+     the use of Project Gutenberg-tm works calculated using the method
+     you already use to calculate your applicable taxes.  The fee is
+     owed to the owner of the Project Gutenberg-tm trademark, but he
+     has agreed to donate royalties under this paragraph to the
+     Project Gutenberg Literary Archive Foundation.  Royalty payments
+     must be paid within 60 days following each date on which you
+     prepare (or are legally required to prepare) your periodic tax
+     returns.  Royalty payments should be clearly marked as such and
+     sent to the Project Gutenberg Literary Archive Foundation at the
+     address specified in Section 4, "Information about donations to
+     the Project Gutenberg Literary Archive Foundation."
+
+- You provide a full refund of any money paid by a user who notifies
+     you in writing (or by e-mail) within 30 days of receipt that s/he
+     does not agree to the terms of the full Project Gutenberg-tm
+     License.  You must require such a user to return or
+     destroy all copies of the works possessed in a physical medium
+     and discontinue all use of and all access to other copies of
+     Project Gutenberg-tm works.
+
+- You provide, in accordance with paragraph 1.F.3, a full refund of any
+     money paid for a work or a replacement copy, if a defect in the
+     electronic work is discovered and reported to you within 90 days
+     of receipt of the work.
+
+- You comply with all other terms of this agreement for free
+     distribution of Project Gutenberg-tm works.
+
+1.E.9.  If you wish to charge a fee or distribute a Project Gutenberg-tm
+electronic work or group of works on different terms than are set
+forth in this agreement, you must obtain permission in writing from
+both the Project Gutenberg Literary Archive Foundation and Michael
+Hart, the owner of the Project Gutenberg-tm trademark.  Contact the
+Foundation as set forth in Section 3 below.
+
+1.F.
+
+1.F.1.  Project Gutenberg volunteers and employees expend considerable
+effort to identify, do copyright research on, transcribe and proofread
+public domain works in creating the Project Gutenberg-tm
+collection.  Despite these efforts, Project Gutenberg-tm electronic
+works, and the medium on which they may be stored, may contain
+"Defects," such as, but not limited to, incomplete, inaccurate or
+corrupt data, transcription errors, a copyright or other intellectual
+property infringement, a defective or damaged disk or other medium, a
+computer virus, or computer codes that damage or cannot be read by
+your equipment.
+
+1.F.2.  LIMITED WARRANTY, DISCLAIMER OF DAMAGES - Except for the "Right
+of Replacement or Refund" described in paragraph 1.F.3, the Project
+Gutenberg Literary Archive Foundation, the owner of the Project
+Gutenberg-tm trademark, and any other party distributing a Project
+Gutenberg-tm electronic work under this agreement, disclaim all
+liability to you for damages, costs and expenses, including legal
+fees.  YOU AGREE THAT YOU HAVE NO REMEDIES FOR NEGLIGENCE, STRICT
+LIABILITY, BREACH OF WARRANTY OR BREACH OF CONTRACT EXCEPT THOSE
+PROVIDED IN PARAGRAPH 1.F.3.  YOU AGREE THAT THE FOUNDATION, THE
+TRADEMARK OWNER, AND ANY DISTRIBUTOR UNDER THIS AGREEMENT WILL NOT BE
+LIABLE TO YOU FOR ACTUAL, DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE OR
+INCIDENTAL DAMAGES EVEN IF YOU GIVE NOTICE OF THE POSSIBILITY OF SUCH
+DAMAGE.
+
+1.F.3.  LIMITED RIGHT OF REPLACEMENT OR REFUND - If you discover a
+defect in this electronic work within 90 days of receiving it, you can
+receive a refund of the money (if any) you paid for it by sending a
+written explanation to the person you received the work from.  If you
+received the work on a physical medium, you must return the medium with
+your written explanation.  The person or entity that provided you with
+the defective work may elect to provide a replacement copy in lieu of a
+refund.  If you received the work electronically, the person or entity
+providing it to you may choose to give you a second opportunity to
+receive the work electronically in lieu of a refund.  If the second copy
+is also defective, you may demand a refund in writing without further
+opportunities to fix the problem.
+
+1.F.4.  Except for the limited right of replacement or refund set forth
+in paragraph 1.F.3, this work is provided to you 'AS-IS' WITH NO OTHER
+WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
+WARRANTIES OF MERCHANTIBILITY OR FITNESS FOR ANY PURPOSE.
+
+1.F.5.  Some states do not allow disclaimers of certain implied
+warranties or the exclusion or limitation of certain types of damages.
+If any disclaimer or limitation set forth in this agreement violates the
+law of the state applicable to this agreement, the agreement shall be
+interpreted to make the maximum disclaimer or limitation permitted by
+the applicable state law.  The invalidity or unenforceability of any
+provision of this agreement shall not void the remaining provisions.
+
+1.F.6.  INDEMNITY - You agree to indemnify and hold the Foundation, the
+trademark owner, any agent or employee of the Foundation, anyone
+providing copies of Project Gutenberg-tm electronic works in accordance
+with this agreement, and any volunteers associated with the production,
+promotion and distribution of Project Gutenberg-tm electronic works,
+harmless from all liability, costs and expenses, including legal fees,
+that arise directly or indirectly from any of the following which you do
+or cause to occur: (a) distribution of this or any Project Gutenberg-tm
+work, (b) alteration, modification, or additions or deletions to any
+Project Gutenberg-tm work, and (c) any Defect you cause.
+
+
+Section  2.  Information about the Mission of Project Gutenberg-tm
+
+Project Gutenberg-tm is synonymous with the free distribution of
+electronic works in formats readable by the widest variety of computers
+including obsolete, old, middle-aged and new computers.  It exists
+because of the efforts of hundreds of volunteers and donations from
+people in all walks of life.
+
+Volunteers and financial support to provide volunteers with the
+assistance they need are critical to reaching Project Gutenberg-tm's
+goals and ensuring that the Project Gutenberg-tm collection will
+remain freely available for generations to come.  In 2001, the Project
+Gutenberg Literary Archive Foundation was created to provide a secure
+and permanent future for Project Gutenberg-tm and future generations.
+To learn more about the Project Gutenberg Literary Archive Foundation
+and how your efforts and donations can help, see Sections 3 and 4
+and the Foundation web page at https://www.pglaf.org.
+
+
+Section 3.  Information about the Project Gutenberg Literary Archive
+Foundation
+
+The Project Gutenberg Literary Archive Foundation is a non profit
+501(c)(3) educational corporation organized under the laws of the
+state of Mississippi and granted tax exempt status by the Internal
+Revenue Service.  The Foundation's EIN or federal tax identification
+number is 64-6221541.  Its 501(c)(3) letter is posted at
+https://pglaf.org/fundraising.  Contributions to the Project Gutenberg
+Literary Archive Foundation are tax deductible to the full extent
+permitted by U.S. federal laws and your state's laws.
+
+The Foundation's principal office is located at 4557 Melan Dr. S.
+Fairbanks, AK, 99712., but its volunteers and employees are scattered
+throughout numerous locations.  Its business office is located at
+809 North 1500 West, Salt Lake City, UT 84116, (801) 596-1887, email
+business@pglaf.org.  Email contact links and up to date contact
+information can be found at the Foundation's web site and official
+page at https://pglaf.org
+
+For additional contact information:
+     Dr. Gregory B. Newby
+     Chief Executive and Director
+     gbnewby@pglaf.org
+
+
+Section 4.  Information about Donations to the Project Gutenberg
+Literary Archive Foundation
+
+Project Gutenberg-tm depends upon and cannot survive without wide
+spread public support and donations to carry out its mission of
+increasing the number of public domain and licensed works that can be
+freely distributed in machine readable form accessible by the widest
+array of equipment including outdated equipment.  Many small donations
+($1 to $5,000) are particularly important to maintaining tax exempt
+status with the IRS.
+
+The Foundation is committed to complying with the laws regulating
+charities and charitable donations in all 50 states of the United
+States.  Compliance requirements are not uniform and it takes a
+considerable effort, much paperwork and many fees to meet and keep up
+with these requirements.  We do not solicit donations in locations
+where we have not received written confirmation of compliance.  To
+SEND DONATIONS or determine the status of compliance for any
+particular state visit https://pglaf.org
+
+While we cannot and do not solicit contributions from states where we
+have not met the solicitation requirements, we know of no prohibition
+against accepting unsolicited donations from donors in such states who
+approach us with offers to donate.
+
+International donations are gratefully accepted, but we cannot make
+any statements concerning tax treatment of donations received from
+outside the United States.  U.S. laws alone swamp our small staff.
+
+Please check the Project Gutenberg Web pages for current donation
+methods and addresses.  Donations are accepted in a number of other
+ways including including checks, online payments and credit card
+donations.  To donate, please visit: https://pglaf.org/donate
+
+
+Section 5.  General Information About Project Gutenberg-tm electronic
+works.
+
+Professor Michael S. Hart was the originator of the Project Gutenberg-tm
+concept of a library of electronic works that could be freely shared
+with anyone.  For thirty years, he produced and distributed Project
+Gutenberg-tm eBooks with only a loose network of volunteer support.
+
+
+Project Gutenberg-tm eBooks are often created from several printed
+editions, all of which are confirmed as Public Domain in the U.S.
+unless a copyright notice is included.  Thus, we do not necessarily
+keep eBooks in compliance with any particular paper edition.
+
+
+Most people start at our Web site which has the main PG search facility:
+
+     https://www.gutenberg.org
+
+This Web site includes information about Project Gutenberg-tm,
+including how to make donations to the Project Gutenberg Literary
+Archive Foundation, how to help produce our new eBooks, and how to
+subscribe to our email newsletter to hear about new eBooks.
+
+
+</pre>
+
+</body>
+</html>
diff --git a/34114-h/images/p171.jpg b/34114-h/images/p171.jpg
new file mode 100644
index 0000000..7934485
--- /dev/null
+++ b/34114-h/images/p171.jpg
diff --git a/34114-h/images/p199.jpg b/34114-h/images/p199.jpg
new file mode 100644
index 0000000..6235342
--- /dev/null
+++ b/34114-h/images/p199.jpg
diff --git a/34114-h/images/p200.jpg b/34114-h/images/p200.jpg
new file mode 100644
index 0000000..a72d209
--- /dev/null
+++ b/34114-h/images/p200.jpg
diff --git a/34114-h/images/p201.jpg b/34114-h/images/p201.jpg
new file mode 100644
index 0000000..c405ef6
--- /dev/null
+++ b/34114-h/images/p201.jpg
diff --git a/34114-h/images/p202.jpg b/34114-h/images/p202.jpg
new file mode 100644
index 0000000..5f978d7
--- /dev/null
+++ b/34114-h/images/p202.jpg
diff --git a/34114-h/images/p203.jpg b/34114-h/images/p203.jpg
new file mode 100644
index 0000000..e0e9fa4
--- /dev/null
+++ b/34114-h/images/p203.jpg
diff --git a/34114-h/images/p204.jpg b/34114-h/images/p204.jpg
new file mode 100644
index 0000000..3b0aa58
--- /dev/null
+++ b/34114-h/images/p204.jpg
diff --git a/34114-h/images/p205.jpg b/34114-h/images/p205.jpg
new file mode 100644
index 0000000..e3f2a21
--- /dev/null
+++ b/34114-h/images/p205.jpg
diff --git a/34114-h/images/p206.jpg b/34114-h/images/p206.jpg
new file mode 100644
index 0000000..728d6aa
--- /dev/null
+++ b/34114-h/images/p206.jpg
diff --git a/34114-h/images/p207.jpg b/34114-h/images/p207.jpg
new file mode 100644
index 0000000..2dd2e54
--- /dev/null
+++ b/34114-h/images/p207.jpg
diff --git a/34114-h/images/p208.jpg b/34114-h/images/p208.jpg
new file mode 100644
index 0000000..d921944
--- /dev/null
+++ b/34114-h/images/p208.jpg
diff --git a/34114-h/images/p209.jpg b/34114-h/images/p209.jpg
new file mode 100644
index 0000000..272d0e5
--- /dev/null
+++ b/34114-h/images/p209.jpg
diff --git a/34114-h/images/p210.jpg b/34114-h/images/p210.jpg
new file mode 100644
index 0000000..19b9b6c
--- /dev/null
+++ b/34114-h/images/p210.jpg
diff --git a/34114-h/images/p211.jpg b/34114-h/images/p211.jpg
new file mode 100644
index 0000000..3a0f2c5
--- /dev/null
+++ b/34114-h/images/p211.jpg
diff --git a/34114-h/images/p212.jpg b/34114-h/images/p212.jpg
new file mode 100644
index 0000000..6aabcf3
--- /dev/null
+++ b/34114-h/images/p212.jpg
diff --git a/34114-h/images/p213.jpg b/34114-h/images/p213.jpg
new file mode 100644
index 0000000..be6abff
--- /dev/null
+++ b/34114-h/images/p213.jpg
diff --git a/34114-h/images/p214.jpg b/34114-h/images/p214.jpg
new file mode 100644
index 0000000..44c45ef
--- /dev/null
+++ b/34114-h/images/p214.jpg
diff --git a/34114-h/images/p215.jpg b/34114-h/images/p215.jpg
new file mode 100644
index 0000000..232b9de
--- /dev/null
+++ b/34114-h/images/p215.jpg
diff --git a/34114-h/images/p216.jpg b/34114-h/images/p216.jpg
new file mode 100644
index 0000000..1df4695
--- /dev/null
+++ b/34114-h/images/p216.jpg
diff --git a/34114-h/images/p217.jpg b/34114-h/images/p217.jpg
new file mode 100644
index 0000000..e586ecc
--- /dev/null
+++ b/34114-h/images/p217.jpg
diff --git a/34114-h/images/p218.jpg b/34114-h/images/p218.jpg
new file mode 100644
index 0000000..31a0456
--- /dev/null
+++ b/34114-h/images/p218.jpg
diff --git a/34114-h/images/title.jpg b/34114-h/images/title.jpg
new file mode 100644
index 0000000..2669b01
--- /dev/null
+++ b/34114-h/images/title.jpg
diff --git a/34114.txt b/34114.txt
new file mode 100644
index 0000000..0bfee47
--- /dev/null
+++ b/34114.txt
@@ -0,0 +1,9333 @@
+The Project Gutenberg EBook of Soap-Making Manual, by E. G. Thomssen
+
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever.  You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at www.gutenberg.org
+
+
+Title: Soap-Making Manual
+       A Practical Handbook on the Raw Materials, Their
+       Manipulation, Analysis and Control in the Modern Soap Plant.
+
+Author: E. G. Thomssen
+
+Release Date: October 22, 2010 [EBook #34114]
+
+Language: English
+
+Character set encoding: ASCII
+
+*** START OF THIS PROJECT GUTENBERG EBOOK SOAP-MAKING MANUAL ***
+
+
+
+
+Produced by David Clarke, Josephine Paolucci and the Online
+Distributed Proofreading Team at https://www.pgdp.net. (This
+file was produced from images generously made available
+by The Internet Archive/American Libraries.)
+
+
+
+
+
+
+
+Soap-Making Manual
+
+A practical handbook on the raw materials, their manipulation, analysis
+and control in the modern soap plant.
+
+By
+
+_E. G. Thomssen, Ph. D._
+
+ILLUSTRATED
+
+
+NEW YORK
+
+D. VAN NOSTRAND COMPANY
+
+EIGHT WARREN STREET
+
+1922
+
+COPYRIGHT 1922
+
+BY
+
+D. VAN NOSTRAND COMPANY
+
+Printed in the United States of America
+
+       *       *       *       *       *
+
+Transcriber's note:
+
+This is a series of articles collected into a book. There are
+differences in spelling and punctuation in the different chapters (e.g.
+cocoanut in one chapter and coconut in another). These differences were
+left in the text as they appeared.
+
+For Text: A word surrounded by a tilde such as ~this~ signifies that
+the word is bolded in the text. A word surrounded by underscores like
+_this_ signifies the word is italics in the text.
+
+For numbers and equations: Parentheses have been added to clarify
+fractions. Underscores before bracketed numbers in equations denote a
+subscript. The Degree symbol has been changed to deg. in the ASCII
+file.
+
+Minor typos have been corrected and footnotes moved to the end of the
+chapters.
+
+       *       *       *       *       *
+
+
+PREFATORY NOTE.
+
+
+The material contained in this work appeared several years ago in serial
+form in the American Perfumer and Essential Oil Review. Owing to the
+numerous requests received, it has been decided to now place before
+those interested, these articles in book form. While it is true that the
+works pertaining to the soapmaking industry are reasonably plentiful,
+books are quite rare, however, which, in a brief volume, will clearly
+outline the processes employed together with the necessary methods of
+analyses from a purely practical standpoint. In the work presented the
+author has attempted to briefly, clearly, and fully explain the
+manufacture of soap in such language that it might be understood by all
+those interested in this industry. In many cases the smaller plants find
+it necessary to dispense with the services of a chemist, so that it is
+necessary for the soapmaker to make his own tests. The tests outlined,
+therefore, are given as simple as possible to meet this condition. The
+formulae submitted are authentic, and in many cases are now being used
+in soapmaking.
+
+In taking up the industry for survey it has been thought desirable to
+first mention and describe the raw materials used; second, to outline
+the processes of manufacture; third, to classify the methods and
+illustrate by formulae the composition of various soaps together with
+their mode of manufacture; fourth, to enumerate the various methods of
+glycerine recovery, including the processes of saponification, and,
+fifth, to give the most important analytical methods which are of value
+to control the process of manufacture and to determine the purity and
+fitness of the raw material entering into it.
+
+It is not the intention of the author to go into great detail in this
+work, nor to outline to any great extent the theoretical side of the
+subject, but rather to make the work as brief as possible, keeping the
+practical side of the subject before him and not going into concise
+descriptions of machinery as is very usual in works on this subject.
+Illustrations are merely added to show typical kinds of machinery used.
+
+The author wishes to take this opportunity of thanking Messrs. L. S.
+Levy and E. W. Drew for the reading of proof, and Mr. C. W. Aiken of the
+Houchin-Aiken Co., for his aid in making the illustrations a success, as
+well as others who have contributed in the compiling of the formulae for
+various soaps. He trusts that this work may prove of value to those
+engaged in soap manufacture.
+
+E. G. T.
+
+January, 1922
+
+
+
+
+TABLE OF CONTENTS.
+
+
+CHAPTER I.                                                      Page.
+
+RAW MATERIALS USED IN SOAP MAKING                                1-30
+
+  1. Soap Defined                                                   1
+
+  2. Oils and Fats                                                1-2
+
+  3. Saponification Defined                                       2-3
+
+  4. Fats and Oils Used in Soap Manufacture                       3-4
+    Fullers' Earth Process for Bleaching Tallow                   4-6
+    Method for Further Improvement of Color in Tallow               6
+    Vegetable Oils                                                6-9
+    Chrome Bleaching of Palm Oil                                 9-12
+    Air Bleaching of Palm Oil                                   12-16
+
+  5. Rancidity of Oils and Fats                                 16-18
+    Prevention of Rancidity                                        18
+
+  6. Chemical Constants of Oils and Fats                        18-19
+
+  7. Oil Hardening or Hydrogenating                             19-21
+
+  8. Grease                                                     21-22
+
+  9. Rosin (Colophony, Yellow Rosin, Resina)                    22-23
+
+  10. Rosin Saponification                                      23-24
+
+  11. Naphthenic Acids                                          24-25
+
+  12. Alkalis                                                   25-26
+    Caustic Soda                                                   26
+    Caustic Potash                                              26-28
+    Sodium Carbonate (Soda Ash)                                 28-29
+    Potassium Carbonate                                            29
+
+  13. Additional Material Used in Soap Making                   29-30
+
+
+CHAPTER II.
+
+CONSTRUCTION AND EQUIPMENT OF A SOAP PLANT                      31-34
+
+
+CHAPTER III.
+
+CLASSIFICATION OF SOAP MAKING METHODS                           35-46
+
+  1. Full Boiled Soaps                                          36-42
+
+  2. Cold Process                                               43-44
+
+  3. Carbonate Saponification                                   45-46
+
+
+CHAPTER IV.
+
+CLASSIFICATION OF SOAPS                                        47-104
+
+  1. Laundry Soap                                                  48
+    Semi-Boiled Laundry Soap                                    49-50
+    Settled Rosin Soap                                          50-54
+
+  2. Chip Soap                                                  54-55
+    Cold Made Chip Soap                                         55-56
+    Unfilled Chip Soap                                             56
+
+  3. Soap Powders                                               56-59
+    Light Powders                                               60-61
+
+  4. Scouring Powders                                              61
+
+  5. Scouring Soap                                              61-62
+
+  6. Floating Soap                                              62-65
+
+  7. Toilet Soap                                                65-68
+    Cheaper Toilet Soaps                                        68-69
+    Run and Glued-up Soaps                                      69-71
+    Curd Soap                                                   71-72
+    Cold Made Toilet Soaps                                      72-73
+    Perfuming and Coloring Toilet Soaps                         73-75
+    Coloring Soap                                               75-76
+
+  8. Medicinal Soaps                                            76-77
+    Sulphur Soaps                                                  77
+    Tar Soap                                                       77
+    Soaps Containing Phenols                                    77-78
+    Peroxide Soap                                                  78
+    Mercury Soaps                                                  78
+    Less Important Medicinal Soaps                              78-79
+
+  9. Castile Soap                                               79-81
+
+  10. Eschweger Soap                                            81-82
+
+  11. Transparent Soap                                          82-84
+    Cold Made Transparent Soap                                  84-87
+
+  12. Shaving Soaps                                             87-90
+    Shaving Powder                                                 90
+    Shaving Cream                                               90-93
+
+  13. Pumice or Sand Soaps                                      93-94
+
+  14. Liquid Soaps                                              94-95
+
+  15. Use of Hardened Oils in Toilet Soaps                      96-98
+
+  16. Textile Soaps                                                98
+    Scouring and Fulling Soaps for Wool                        98-100
+    Wool Thrower's Soap                                       100-101
+    Worsted Finishing Soaps                                       101
+    Soaps Used in the Silk Industry                           101-103
+    Soaps Used for Cotton Goods                               103-104
+
+  17. Sulphonated Oils                                        104-105
+
+
+CHAPTER V.
+
+GLYCERINE RECOVERY                                            105-126
+
+  1. Methods of Saponification                                105-106
+     Recovery of Glycerine from Spent Lye                     106-113
+     Twitchell Process                                        113-118
+     Autoclave Saponification                                     118
+     Lime Saponification                                      118-120
+     Acid Saponification                                      120-121
+     Aqueous Saponification                                       121
+     Splitting Fats with Ferments                             121-123
+     Krebitz Process                                          123-125
+
+  2. Distillation of Fatty Acids                              125-126
+
+
+CHAPTER VI.
+
+ANALYTICAL METHODS                                            127-164
+
+  1. Analysis of Oils and Fats                                    128
+     Free Fatty Acids                                         128-130
+     Moisture                                                     130
+     Titer                                                    130-132
+     Determination of Unsaponifiable Matter                   132-133
+     Test for Color of Soap                                   133-134
+     Testing of Alkalis Used in Soap Making                   134-137
+
+  2. Soap Analysis                                            137-138
+     Moisture                                                 138-139
+     Free Alkali or Acid                                      139-142
+     Insoluble Matter                                             143
+     Starch and Gelatine                                      143-144
+     Total Fatty and Resin Acids                                  144
+     Determination of Rosin                                   144-147
+     Total Alkali                                             147-148
+     Unsaponifiable Matter                                        148
+     Silica and Silicates                                     148-149
+     Glycerine in Soap                                        149-150
+     Sugar in Soap                                                150
+
+  3. Glycerine Analysis                                       150-151
+     Sampling                                                     151
+     Analysis                                                 151-154
+     Acetin Process for the Determination of Glycerol         155-156
+     The Method                                               156-159
+     Ways of Calculating Actual Glycerol Contents             159-160
+     Bichromate Process for Glycerol Determination
+       Reagents Required                                      160-161
+     The Method                                               161-162
+     Sampling Crude Glycerine                                 162-164
+
+
+CHAPTER VII
+
+STANDARD METHODS FOR THE SAMPLING AND ANALYSIS OF
+COMMERCIAL FATS AND OILS                                      165-195
+
+  1. Scope, Applicability and Limitations of the Methods      165-166
+    Scope                                                         165
+    Applicability                                                 166
+    Limitations                                                   166
+    Sampling                                                  166-169
+    Tank Cars                                                 166-167
+    Barrels, Tierces, Casks, Drums, and Other Packages            168
+
+  2. Analysis                                                 169-183
+    Sample                                                        169
+    Moisture and Volatile Matter                              170-172
+    Insoluble Impurities                                      172-173
+    Soluble Mineral Matter                                        173
+    Free Fatty Acids                                              174
+    Titer                                                     174-175
+    Unsaponifiable Matter                                     176-177
+    Iodine Number-Wijs Method                                 177-181
+    Saponification Number (Koettstorfer Number)                   181
+    Melting Point                                             181-182
+    Cloud Test                                                182-184
+
+  3. Notes of the Above Methods                               184-196
+    Sampling                                                      183
+    Moisture and Volatile Matter                              184-187
+    Insoluble Impurities                                          187
+    Soluble Mineral Matter                                    187-188
+    Free Fatty Acid                                           188-189
+    Titer                                                         189
+    Unsaponified Matter                                       190-193
+    Melting Point                                             193-196
+
+Plant and Machinery                                           198-219
+    Illustrations of Machinery and Layouts of the Plant
+    of a Modern Soap Making Establishment                     198-219
+
+Appendix                                                      219-237
+
+    Useful Tables
+
+Index                                                             239
+
+
+
+
+CHAPTER I
+
+Raw Materials Used in Soap Making.
+
+
+Soap is ordinarily thought of as the common cleansing agent well known
+to everyone. In a general and strictly chemical sense this term is
+applied to the salts of the non-volatile fatty acids. These salts are
+not only those formed by the alkali metals, sodium and potassium, but
+also those formed by the heavy metals and alkaline earths. Thus we have
+the insoluble soaps of lime and magnesia formed when we attempt to wash
+in "hard water"; again aluminum soaps are used extensively in polishing
+materials and to thicken lubricating oils; ammonia or "benzine" soaps
+are employed among the dry cleaners. Commonly, however, when we speak of
+soap we limit it to the sodium or potassium salt of a higher fatty acid.
+
+It is very generally known that soap is made by combining a fat or oil
+with a water solution of sodium hydroxide (caustic soda lye), or
+potassium hydroxide (caustic potash). Sodium soaps are always harder
+than potassium soaps, provided the same fat or oil is used in both
+cases.
+
+The detergent properties of soap are due to the fact that it acts as an
+alkali regulator, that is, when water comes into contact with soap, it
+undergoes what is called hydrolytic dissociation. This means that it is
+broken down by water into other substances. Just what these substances
+are is subject to controversy, though it is presumed caustic alkali and
+the acid alkali salt of the fatty acids are formed.
+
+
+OILS AND FATS.
+
+There is no sharp distinction between fat and oil. By "oil" the layman
+has the impression of a liquid which at warm temperature will flow as a
+slippery, lubricating, viscous fluid; by "fat" he understands a greasy,
+solid substance unctuous to the touch. It thus becomes necessary to
+differentiate the oils and fats used in the manufacture of soap.
+
+Inasmuch as a soap is the alkali salt of a fatty acid, the oil or fat
+from which soap is made must have as a constituent part, these fatty
+acids. Hydrocarbon oils or paraffines, included in the term "oil," are
+thus useless in the process of soap-making, as far as entering into
+chemical combination with the caustic alkalis is concerned. The oils and
+fats which form soap are those which are a combination of fatty acids
+and glycerine, the glycerine being obtained as a by-product to the
+soap-making industry.
+
+
+NATURE OF A FAT OR OIL USED IN SOAP MANUFACTURE.
+
+Glycerine, being a trihydric alcohol, has three atoms of hydrogen which
+are replaceable by three univalent radicals of the higher members of the
+fatty acids, _e. g._,
+
+                OH                       OR
+    C_{3} H_{5} OH + 3 ROH = C_{3} H_{5} OR + 3 H_{2}O
+                OH                       OR
+
+Glycerine plus 3 Fatty Alcohols equals Fat or Oil plus 3 Water.
+
+Thus three fatty acid radicals combine with one glycerine to form a true
+neutral oil or fat which are called triglycerides. The fatty acids which
+most commonly enter into combination of fats and oils are lauric,
+myristic, palmitic, stearic and oleic acids and form the neutral oils or
+triglycerides derived from these, _e. g._, stearin, palmatin, olein.
+Mono and diglycerides are also present in fats.
+
+
+SAPONIFICATION DEFINED.
+
+When a fat or oil enters into chemical combination with one of the
+caustic hydrates in the presence of water, the process is called
+"saponification" and the new compounds formed are soap and glycerine,
+thus:
+
+               OR                       OH
+    C_{3}H_{5} OR + 3 NaOH = C_{3}H_{5} OH + 3 NaOR
+               OR                       OH
+
+Fat or Oil plus 3 Sodium Hydrate equals Glycerine plus 3 Soap.
+
+It is by this reaction almost all of the soap used today is made.
+
+There are also other means of saponification, as, the hydrolysis of an
+oil or fat by the action of hydrochloric or sulfuric acid, by autoclave
+and by ferments or enzymes. By these latter processes the fatty acids
+and glycerine are obtained directly, no soap being formed.
+
+
+FATS AND OILS USED IN SOAP MANUFACTURE.
+
+The various and most important oils and fats used in the manufacture of
+soap are, tallow, cocoanut oil, palm oil, olive oil, poppy oil, sesame
+oil, soya bean oil, cotton-seed oil, corn oil and the various greases.
+Besides these the fatty acids, stearic, red oil (oleic acid) are more or
+less extensively used. These oils, fats and fatty acids, while they vary
+from time to time and to some extent as to their color, odor and
+consistency, can readily be distinguished by various physical and
+chemical constants.
+
+Much can be learned by one, who through continued acquaintance with
+these oils has thoroughly familiarized himself with the indications of a
+good or bad oil, by taste, smell, feel and appearance. It is, however,
+not well for the manufacturer in purchasing to depend entirely upon
+these simpler tests. Since he is interested in the yield of glycerine,
+the largest possible yield of soap per pound of soap stock and the
+general body and appearance of the finished product, the chemical tests
+upon which these depend should be made. Those especially important are
+the acid value, percentage unsaponifiable matter and titer test.
+
+A short description of the various oils and fats mentioned is sufficient
+for their use in the soap industry.
+
+_Tallow_ is the name given to the fat extracted from the solid fat or
+"suet" of cattle, sheep or horses. The quality varies greatly, depending
+upon the seasons of the year, the food and age of the animal and the
+method of rendering. It comes to the market under the distinction of
+edible and inedible, a further distinction being made in commerce as
+beef tallow, mutton tallow or horse tallow. The better quality is white
+and bleaches whiter upon exposure to air and light, though it usually
+has a yellowish tint, a well defined grain and a clean odor. It consists
+chiefly of stearin, palmitin and olein. Tallow is by far the most
+extensively used and important fat in the making of soap.
+
+In the manufacture of soaps for toilet purposes, it is usually necessary
+to produce as white a product as possible. In order to do this it often
+is necessary to bleach the tallow before saponification. The method
+usually employed is the Fuller's Earth process.
+
+
+FULLER'S EARTH PROCESS FOR BLEACHING TALLOW.
+
+From one to two tons of tallow are melted out into the bleaching tank.
+This tank is jacketed, made of iron and provided with a good agitator
+designed to stir up sediment or a coil provided with tangential downward
+opening perforations and a draw-off cock at the bottom. The coil is the
+far simpler arrangement, more cleanly and less likely to cause trouble.
+By this arrangement compressed air which is really essential in the
+utilization of the press (see later) is utilized for agitation. A dry
+steam coil in an ordinary tank may be employed in place of a jacketed
+tank, which lessens the cost of installation.
+
+The tallow in the bleaching tank is heated to 180deg. F. (82deg. C.) and
+ten pounds of dry salt per ton of fat used added and thoroughly mixed by
+agitation. This addition coagulates any albumen and dehydrates the fat.
+The whole mass is allowed to settle over night where possible, or for at
+least five hours. Any brine which has separated is drawn off from the
+bottom and the temperature of the fat is then raised to 160deg. F.
+(71deg. C).
+
+Five per cent. of the weight of the tallow operated upon, of dry
+Fuller's earth is now added and the whole mass agitated from twenty to
+thirty minutes.
+
+The new bleached fat, containing the Fuller's earth is pumped directly
+to a previously heated filter press and the issuing clear oil run
+directly to the soap kettle.
+
+One of the difficulties experienced in the process is the heating of the
+press to a temperature sufficient to prevent solidification of the fat
+without raising the press to too great a temperature. To overcome this
+the first plate is heated by wet steam. Air delivered from a blower and
+heated by passage through a series of coils raised to a high temperature
+by external application of heat (super-heated steam) is then substituted
+for the steam. The moisture produced by the condensation of the steam is
+vaporized by the hot air and carried on gradually to each succeeding
+plate where it again condenses and vaporizes. In this way the small
+quantity of water is carried through the entire press, raising its
+temperature to 80deg.-100deg. C. This temperature is subsequently
+maintained by the passage of hot air. By this method of heating the poor
+conductivity of hot air is overcome through the intermediary action of a
+liquid vapor and the latent heat of steam is utilized to obtain the
+initial rise in temperature. To heat a small press economically where
+conditions are such that a large output is not required the entire press
+may be encased in a small wooden house which can be heated by steam
+coils. The cake in the press is heated for some time after the
+filtration is complete to assist drainage. After such treatment the cake
+should contain approximately 15 per cent. fat and 25 per cent. water.
+The cake is now removed from the press and transferred to a small tank
+where it is treated with sufficient caustic soda to convert the fat
+content into soap.
+
+Saturated brine is then added to salt out the soap, the Fuller's earth
+is allowed to settle to the bottom of the tank and the soap which
+solidifies after a short time is skimmed off to be used in a cheap soap
+where color is not important. The liquor underneath may also be run off
+without disturbing the sediment to be used in graining a similar cheap
+soap. The waste Fuller's earth contains about 0.1 to 0.3 per cent. of
+fat.
+
+
+METHOD FOR FURTHER IMPROVEMENT OF COLOR.
+
+A further improvement of the color of the tallow may be obtained by
+freeing it from a portion of its free fatty acids, either with or
+without previous Fuller's earth bleaching.
+
+To carry out this process the melted fat is allowed to settle and as
+much water as possible taken off. The temperature is then raised to 160deg.
+F. with dry steam and enough saturated solution of soda ash added to
+remove 0.5 per cent. of the free fatty acids, while agitating the mass
+thoroughly mechanically or by air. The agitation is continued ten
+minutes, the whole allowed to settle for two hours and the foots drawn
+off. The soap thus formed entangles a large proportion of the impurities
+of the fat.
+
+
+VEGETABLE OILS.
+
+_Cocoanut Oil_, as the name implies, is obtained from the fruit of the
+cocoanut palm. This oil is a solid, white fat at ordinary temperature,
+having a bland taste and a characteristic odor. It is rarely
+adulterated and is very readily saponified. In recent years the price of
+this oil has increased materially because cocoanut oil is now being used
+extensively for edible purposes, especially in the making of
+oleomargarine. Present indications are that shortly very little high
+grade oil will be employed for soap manufacture since the demand for
+oleomargarine is constantly increasing and since new methods of refining
+the oil for this purpose are constantly being devised.
+
+The oil is found in the market under three different grades: (1) Cochin
+cocoanut oil, the choicest oil comes from Cochin (Malabar). This
+product, being more carefully cultivated and refined than the other
+grades, is whiter, cleaner and contains a smaller percentage of free
+acid. (2) Ceylon cocoanut oil, coming chiefly from Ceylon, is usually of
+a yellowish tint and more acrid in odor than Cochin oil. (3) Continental
+cocoanut oil (Copra, Freudenberg) is obtained from the dried kernels,
+the copra, which are shipped to Europe in large quantities, where the
+oil is extracted. These dried kernels yield 60 to 70 per cent oil. This
+product is generally superior to the Ceylon oil and may be used as a
+very satisfactory substitute for Cochin oil, in soap manufacture,
+provided it is low in free acid and of good color. The writer has
+employed it satisfactorily in the whitest and finest of toilet soaps
+without being able to distinguish any disadvantage to the Cochin oil.
+Since continental oil is usually cheaper than Cochin oil, it is
+advisable to use it, as occasion permits.
+
+Cocoanut oil is used extensively in toilet soap making, usually in
+connection with tallow. When used alone the soap made from this oil
+forms a lather, which comes up rapidly but which is fluffy and dries
+quickly. A pure tallow soap lathers very much slower but produces a more
+lasting lather. Thus the advantage of using cocoanut oil in soap is
+seen. It is further used in making a cocoanut oil soap by the cold
+process also for "fake" or filled soaps. The fatty acid content readily
+starts the saponification which takes place easily with a strong lye
+(25deg.-35deg. B.). Where large quantities of the oil are saponified
+care must be exercised as the soap formed suddenly rises or puffs up and
+may boil over. Cocoanut oil soap takes up large quantities of water,
+cases having been cited where a 500 per cent. yield has been obtained.
+This water of course dries out again upon exposure to the air. The soap
+is harsh to the skin, develops rancidity and darkens readily.
+
+_Palm Kernel Oil_, which is obtained from the kernels of the palm tree
+of West Africa, is used in soap making to replace cocoanut oil where the
+lower price warrants its use. It resembles cocoanut oil in respect to
+saponification and in forming a very similar soap. Kernel oil is white
+in color, has a pleasant nutty odor when fresh, but rapidly develops
+free acid, which runs to a high percentage.
+
+_Palm Oil_ is produced from the fruit of the several species of the palm
+tree on the western coast of Africa generally, but also in the
+Philippines. The fresh oil has a deep orange yellow tint not destroyed
+by saponification, a sweetish taste and an odor of orris root or violet
+which is also imparted to soap made from it. The methods by which the
+natives obtain the oil are crude and depend upon a fermentation, or
+putrefaction. Large quantities are said to be wasted because of this
+fact. The oil contains impurities in the form of fermentable fibre and
+albuminous matter, and consequently develops free fatty acid rapidly.
+Samples tested for free acid have been found to have hydrolized
+completely and one seldom obtains an oil with low acid content. Because
+of this high percentage of free fatty acid, the glycerine yield is
+small, though the neutral oil should produce approximately 12 per cent.
+glycerine. Some writers claim that glycerine exists in the free state
+in palm oil. The writer has washed large quantities of the oil and
+analyzed the wash water for glycerine. The results showed that the
+amount present did not merit its recovery. Most soap makers do not
+attempt to recover the glycerine from this oil, when used alone for soap
+manufacture.
+
+There are several grades of palm oil in commerce, but in toilet soap
+making it is advisable to utilize only Lagos palm oil, which is the best
+grade. Where it is desired to maintain the color of the soap this oil
+produces, a small quantity of the lower or "brass" grade of palm oil may
+be used, as the soap made from the better grades of oil gradually
+bleaches and loses its orange yellow color.
+
+Palm oil produces a crumbly soap which cannot readily be milled and is
+termed "short." When used with tallow and cocoanut oil, or 20 to 25 per
+cent. cocoanut oil, it produces a very satisfactory toilet soap. In the
+saponification of palm oil it is not advisable to combine it with tallow
+in the kettle, as the two do not readily mix.
+
+Since the finished soap has conveyed to it the orange color of the oil,
+the oil is bleached before saponification. Oxidation readily destroys
+the coloring matter, while heat and light assist materially. The methods
+generally employed are by the use of oxygen developed by bichromates and
+hydrochloric acid and the direct bleaching through the agency of the
+oxygen of the air.
+
+
+CHROME BLEACHING OF PALM OIL.
+
+The chrome process of bleaching palm oil is more rapid and the oxygen
+thus derived being more active will bleach oils which air alone cannot.
+It depends upon the reaction:
+
+    Na_{2}Cr_{2}O_{7} + 8HCl = Cr_{2}Cl_{6} + 2NaCl + 7O.
+
+in which the oxygen is the active principle. In practice it is found
+necessary to use an excess of acid over that theoretically indicated.
+
+For the best results an oil should be chosen containing under 2 per
+cent. impurities and a low percentage of free fatty acids. Lagos oil is
+best adapted to these requirements. The oil is melted by open steam from
+a jet introduced through the bung, the melted oil and condensed water
+running to the store tank through two sieves (about 1/8 inch mesh) to
+remove the fibrous material and gross impurities. The oil thus obtained
+contains fine earthy and fibrous material and vegetable albuminous
+matter which should be removed, as far as possible, since chemicals are
+wasted in their oxidation and they retard the bleaching. This is best
+done by boiling the oil for one hour with wet steam and 10 per cent.
+solution of common salt (2 per cent. dry salt on weight of oil used) in
+a lead-lined or wooden tank. After settling over night the brine and
+impurities are removed by running from a cock at the bottom of the vat
+and the oil is run out into the bleaching tank through an oil cock,
+situated about seven inches from the bottom.
+
+The bleaching tank is a lead-lined iron tank of the approximate
+dimensions of 4 feet deep, 4 feet long and 3-1/2 feet wide, holding
+about 1-1/2 tons. The charge is one ton. A leaden outlet pipe is fixed
+at the bottom, to which is attached a rubber tube closed by a screw
+clip. A plug also is fitted into the lead outlet pipe from above. Seven
+inches above the lower outlet is affixed another tap through which the
+oil is drawn off.
+
+The tank is further equipped with a wet steam coil and a coil arranged
+to allow thorough air agitation, both coils being of lead. A good
+arrangement is to use one coil to deliver either air or steam. These
+coils should extend as nearly as possible over the entire bottom of the
+tank and have a number of small downward perforations, so as to spread
+the agitation throughout the mass.
+
+The temperature of the oil is reduced by passing in air to 110deg. F. and
+40 pounds of fine common salt per ton added through a sieve. About
+one-half of the acid (40 pounds of concentrated commercial hydrochloric
+acid) is now poured in and this is followed by the sodium bichromate in
+concentrated solution, previously prepared in a small lead vat or
+earthen vessel by dissolving 17 pounds of bichromate in 45 pounds
+commercial hydrochloric acid. This solution should be added slowly and
+should occupy three hours, the whole mass being thoroughly agitated with
+air during the addition and for one hour after the last of the bleaching
+mixture has been introduced. The whole mixture is now allowed to settle
+for one hour and the exhausted chrome liquors are then run off from the
+lower pipe to a waste tank. About 40 gallons of water are now run into
+the bleached oil and the temperature raised by open steam to 150deg. to
+160deg. F. The mass is then allowed to settle over night.
+
+One such wash is sufficient to remove the spent chrome liquor
+completely, provided ample time is allowed for settling. A number of
+washings given successively with short periods of settling do not remove
+the chrome liquors effectually. The success of the operation depends
+entirely upon the completeness of settling.
+
+The wash water is drawn off as before and the clear oil run to storage
+tanks or to the soap kettle through the upper oil cock.
+
+The waste liquors are boiled with wet steam and the oil skimmed from the
+surface, after which the liquors are run out through an oil trap.
+
+By following the above instructions carefully it is possible to bleach
+one ton of palm oil with 17 pounds of bichromate of soda and 85 pounds
+hydrochloric acid.
+
+The spent liquors should be a bright green color. Should they be of a
+yellow or brownish shade insufficient acid has been allowed and more
+must be added to render the whole of the oxygen available.
+
+If low grade oils are being treated more chrome will be necessary, the
+amount being best judged by conducting the operation as usual and after
+the addition of the bichromate, removing a sample of the oil, washing
+the sample and noting the color of a rapidly cooled sample.
+
+A little practice will enable the operator to judge the correspondence
+between the color to be removed and the amount of bleaching mixture to
+be added.
+
+To obtain success with this process the method of working given must be
+adhered to even in the _smallest detail_. This applies to the
+temperature at which each operation is carried out particularly.
+
+
+AIR BLEACHING OF PALM OIL.
+
+The method of conducting this process is identical with the chrome
+process to the point where the hydrochloric acid is to be added to the
+oil. In this method no acid or chrome is necessary, as the active
+bleaching agent is the oxygen of the air.
+
+The equipment is similar to that of the former process, except that a
+wooden tank in which no iron is exposed will suffice to bleach the oil
+in. The process depends in rapidity upon the amount of air blown through
+the oil and its even distribution. Iron should not be present or exposed
+to the oil during bleaching, as it retards the process considerably.
+
+After the impurities have been removed, as outlined under the chrome
+process, the temperature of the oil is raised by open steam to boiling.
+The steam is then shut off and air allowed to blow through the oil until
+it is completely bleached, the temperature being maintained above 150deg.
+F. by occasionally passing in steam. Usually a ton of oil is readily and
+completely bleached after the air has been passed through it for 18 to
+20 hours, provided the oil is thoroughly agitated by a sufficient flow
+of air.
+
+If the oil has been allowed to settle over night, it is advisable to run
+off the condensed water and impurities by the lower cock before
+agitating again the second day.
+
+When the oil has been bleached to the desired color, which can be
+determined by removing a sample and cooling, the mass is allowed to
+settle, the water run off to a waste tank from which any oil carried
+along may be skimmed off and the supernatant clear oil run to the
+storage or soap kettle.
+
+In bleaching by this process, while the process consumes more time and
+is not as efficient in bleaching the lower grade oils, the cost of
+bleaching is less and with a good oil success is more probable, as there
+is no possibility of any of the chrome liquors being present in the oil.
+These give the bleached oil a green tint when the chrome method is
+improperly conducted and they are not removed.
+
+Instead of blowing the air through it, the heater oil may be brought
+into contact with the air, either by a paddle wheel arrangement, which,
+in constantly turning, brings the oil into contact with the air, or by
+pumping the heated oil into an elevated vessel, pierced with numerous
+fine holes from which the oil continuously flows back into the vessel
+from which the oil is pumped. While in these methods air, light and heat
+act simultaneously in the bleaching of the oil, the equipment required
+is too cumbersome to be practical.
+
+Recent investigations[1] in bleaching palm oil by oxygen have shown that
+not only the coloring matter but the oil itself was affected. In
+bleaching palm oil for 30 hours with air the free fatty acid content
+rose and titer decreased considerably.
+
+_Olive Oil_, which comes from the fruit of the olive trees, varies
+greatly in quality, according to the method by which it is obtained and
+according to the tree bearing the fruit. Three hundred varieties are
+known in Italy alone. Since the larger portion of olive oil is used for
+edible purposes, a lower grade, denatured oil, denatured because of the
+tariff, is used for soap manufacture in this country. The oil varies in
+color from pale green to golden yellow. The percentage of free acid in
+this oil varies greatly, though the oil does not turn rancid easily. It
+is used mainly in the manufacture of white castile soap.
+
+Olive oil foots, which is the oil extracted by solvents after the better
+oil is expressed, finds its use in soap making mostly in textile soaps
+for washing and dyeing silks and in the production of green castile
+soaps.
+
+Other oils, as poppy seed oil, sesame oil, cottonseed oil, rape oil,
+peanut (arachis) oil, are used as adulterants for olive oil, also as
+substitutes in the manufacture of castile soap, since they are cheaper
+than olive oil.
+
+_Cottonseed Oil_ is largely used in the manufacture of floating and
+laundry soaps. It may be used for toilet soaps where a white color is
+not desired, as yellow spots appear on a finished soap in which it has
+been used after having been in stock a short time.
+
+_Corn Oil and Soya Bean Oil_ are also used to a slight extent in the
+manufacture of toilet soaps, although the oils form a soap of very
+little body. Their soaps also spot yellow on aging.
+
+Corn oil finds its greatest use in the manufacture of soap for washing
+automobiles. It is further employed for the manufacture of cheap liquid
+soaps.
+
+_Fatty Acids_ are also used extensively in soap manufacture. While the
+soap manufacturer prefers to use a neutral oil or fat, since from these
+the by-product glycerine is obtained, circumstances arise where it is
+an advantage to use the free fatty acids. Red oil (oleic acid, elaine)
+and stearic acid are the two fatty acids most generally bought for soap
+making. In plants using the Twitchell process, which consists in
+splitting the neutral fats and oils into fatty acids and glycerine by
+dilute sulphuric acid and producing their final separation by the use of
+so-called aromatic sulphonic acids, these fatty acids consisting of a
+mixture of oleic, stearic, palmitic acids, etc., are used directly after
+having been purified by distillation, the glycerine being obtained from
+evaporating the wash water.
+
+Oleic acid (red oil) and stearic acid are obtained usually by the
+saponification of oils, fats and greases by acid, lime or water under
+pressure or Twitchelling. The fatty acids thus are freed from their
+combination with glycerine and solidify upon cooling, after which they
+are separated from the water and pressed at a higher or lower
+temperature. The oleic acid, being liquid at ordinary temperature,
+together with some stearic and palmitic acid, is thus pressed out. These
+latter acids are usually separated by distillation, combined with the
+press cake further purified and sold as stearic acid.
+
+The red oil, sometimes called saponified red oil, is often semi-solid,
+resembling a soft tallow, due to the presence of stearic acid. The
+distilled oils are usually clear, varying in color from light to a deep
+brown. Stearic acid, which reaches the trade in slab form, varies in
+quality from a soft brown, greasy, crumbly solid of unpleasant odor to a
+snow white, wax-like, hard, odorless mass. The quality of stearic acid
+is best judged by the melting point, since the presence of any oleic
+acid lowers this. The melting point of the varieties used in soap
+manufacture usually ranges from 128deg. to 132deg. F. Red oil is used in
+the manufacture of textile soaps, replacing olive oil foots soap for
+this purpose, chlorophyll being used to color the soap green. Stearic
+acid, being the hard firm fatty acid, may be used in small quantities to
+give a better grade of soap body and finish. In adding this substance it
+should always be done in the crutcher, as it will not mix in the kettle.
+It finds its largest use for soap, however, in the manufacture of
+shaving soaps and shaving creams, since it produces the non-drying
+creamy lather so greatly desired for this purpose. Both red oil and
+stearic acid being fatty acids, readily unite with the alkali
+carbonates, carbon dioxide being formed in the reaction and this method
+is extensively used in the formation of soap from them.
+
+
+RANCIDITY OF OILS AND FATS.
+
+Rancidity in neutral oils and fats is one of the problems the soap
+manufacturer has to contend with. The mere saying that an oil is rancid
+is no indication of its being high in free acid. The two terms rancidity
+and acidity are usually allied. Formerly, the acidity of a fat was
+looked upon as the direct measure of its rancidity. This idea is still
+prevalent in practice and cannot be too often stated as incorrect. Fats
+and oils may be _acid_, or _rancid_, or _acid and rancid_. In an acid
+fat there has been a hydrolysis of the fat and it has developed a rather
+high percentage of free acid. A rancid fat is one in which have been
+developed compounds of an odoriferous nature. An acid and rancid fat is
+one in which both free acid and organic compounds of the well known
+disagreeable odors have been produced.
+
+It cannot be definitely stated just how this rancidity takes place, any
+more than just what are the chemical products causing rancidity. The
+only conclusion that one may draw is that the fats are first hydrolyzed
+or split up into glycerine and free fatty acids. This is followed by an
+oxidation of the products thus formed.
+
+Moisture, air, light, enzymes (organized ferments) and bacteria are all
+given as causes of rancidity.
+
+It seems very probable that the initial splitting of the fats is caused
+by enzymes, which are present in the seeds and fruits of the vegetable
+oils and tissue of animal fats, in the presence of moisture. Lewkowitsch
+strongly emphasizes this point and he is substantiated in his idea by
+other authorities. Others hold that bacteria or micro-organisms are the
+cause of this hydrolysis, citing the fact that they have isolated
+various micro-organisms from various fats and oils. The acceptance of
+the bacterial action would explain the various methods of preservation
+of oils and fats by the use of antiseptic preparations. It cannot,
+however, be accepted as a certainty that bacteria cause the rancidity of
+fats.
+
+The action of enzymes is a more probable explanation.
+
+The hydrolysis of fats and oils is accelerated when they are allowed to
+remain for some time in the presence of organic non-fats. Thus, palm
+oil, lower grades of olive oil, and tallow, which has been in contact
+with the animal tissue for a long time, all contain other nitrogenous
+matter and exhibit a larger percentage of free fatty acid than the oils
+and fats not containing such impurities.
+
+Granting this initial splitting of the fat into free fatty acids and
+glycerine, this is not a sufficient explanation. The products thus
+formed must be acted upon by air and light. It is by the action of these
+agents that there is a further action upon the products, and from this
+oxidation we ascertain by taste and smell (chemical means are still
+unable to define rancidity) whether or not a fat is rancid. While some
+authorities have presumed to isolate some of these products causing
+rancidity, we can only assume the presence of the various possible
+compounds produced by the action of air and light which include oxy
+fatty acids, lactones, alcohols, esters, aldehydes and other products.
+
+The soap manufacturer is interested in rancidity to the extent of the
+effect upon the finished soap. Rancid fats form darker soaps than fats
+in the neutral state, and very often carry with them the disagreeable
+odor of a rancid oil. Further, a rancid fat or oil is usually high in
+free acid. It is by no means true, however, that rancidity is a measure
+for acidity, for as has already been pointed out, an oil may be rancid
+and not high in free acid.
+
+The percentage of free fatty acid is of even greater importance in the
+soap industry. The amount of glycerine yield is dependent upon the
+percentage of free fatty acid and is one of the criterions of a good fat
+or oil for soap stock.
+
+
+PREVENTION OF RANCIDITY.
+
+Since moisture, air, light and enzymes, produced by the presence of
+organic impurities, are necessary for the rancidity of a fat or oil, the
+methods of preventing rancidity are given. Complete dryness, complete
+purification of fats and oils and storage without access of air or light
+are desirable. Simple as these means may seem, they can only be
+approximated in practice. The most difficult problem is the removal of
+the last trace of moisture. Impurities may be lessened very often by the
+use of greater care. In storing it is well to store in closed barrels or
+closed iron tanks away from light, as it has been observed that oils and
+fats in closed receptacles become rancid less rapidly than those in open
+ones, even though this method of storing is only partially attained.
+Preservatives are also used, but only in edible products, where their
+effectiveness is an open question.
+
+
+CHEMICAL CONSTANTS OF OILS AND FATS.
+
+Besides the various physical properties of oils and fats, such as
+color, specific gravity, melting point, solubility, etc., they may be
+distinguished chemically by a number of chemical constants. These are
+the iodine number, the acetyl value, saponification number,
+Reichert-Meissl number for volatile acids, Hehner number for insoluble
+acids. These constants, while they vary somewhat with any particular oil
+or fat, are more applicable to the edible products and are criterions
+where any adulteration of fat or oil is suspected. The methods of
+carrying out the analyses of oils and fats to obtain these constants are
+given in the various texts[2] on oils and fats, and inasmuch as they are
+not of great importance to the soap industry they are merely mentioned
+here.
+
+
+OIL HARDENING OR HYDROGENATING.
+
+It is very well known that oils and fats vary in consistency and
+hardness, depending upon the glycerides forming same. Olein, a
+combination of oleic acid and glycerine, as well as oleic acid itself
+largely forms the liquid portion of oils and fats. Oleic acid
+(C_{18}H_{34}O_{2}) is an unsaturated acid and differs from stearic acid
+(C_{18}H_{36}O_{2}), the acid forming the hard firm portion of oils and
+fats, by containing two atoms of hydrogen less in the molecule.
+Theoretically it should be a simple matter to introduce two atoms of
+hydrogen into oleic acid or olein, and by this mere addition convert
+liquid oleic acid and olein into solid stearic acid and stearine.
+
+For years this was attempted and all attempts to apply the well known
+methods of reduction (addition of hydrogen) in organic chemistry, such
+as treatment with tin and acid, sodium amalgam, etc., were unsuccessful.
+In recent years, however, it has been discovered that in the presence of
+a catalyzer, nickel in finely divided form or the oxides of nickel are
+usually employed, the process of hydrogenating an oil is readily
+attained upon a practical basis.
+
+The introduction of hardened oils has opened a new source of raw
+material for the soap manufacturer in that it is now possible to use
+oils in soap making which were formerly discarded because of their
+undesirable odors. Thus fish or train oils which had up to the time of
+oil hydrogenating resisted all attempts of being permanently deodorized,
+can now be employed very satisfactorily for soap manufacture. A Japanese
+chemist, Tsujimoto[3] has shown that fish oils contain an unsaturated
+acid of the composition C_{18}H_{28}O_{2}, for which he proposed the
+name clupanodonic acid. By the catalytic hardening of train oils this
+acid passes to stearic acid and the problem of deodorizing these oils is
+solved.[4]
+
+At first the introduction of hardened oils for soap manufacture met with
+numerous objections, due to the continual failures of obtaining a
+satisfactory product by the use of same. Various attempts have now shown
+that these oils, particularly hardened train oils, produce
+extraordinarily useful materials for soap making. These replace
+expensive tallow and other high melting oils. It is of course impossible
+to employ hardened oils alone, as a soap so hard would thus be obtained
+that it would be difficultly soluble in water and possess very little
+lathering quality. By the addition of 20-25% of tallow oil or some other
+oil forming a soft soap a very suitable soap for household use may be
+obtained. Ribot[5] discusses this matter fully. Hardened oils readily
+saponify, may be perfumed without any objections and do not impart any
+fishy odor to an article washed with same. Meyerheim[6] states that
+through the use of hydrogenated oils the hardness of soap is
+extraordinarily raised, so that soap made from hardened cottonseed oil
+is twelve times as hard as the soap made from ordinary cottonseed oil.
+This soap is also said to no longer spot yellow upon aging, and as a
+consequence of its hardness, is able to contain a considerably higher
+content of rosin through which lathering power and odor may be improved.
+Hardened oils can easily be used for toilet soap bases, provided they
+are not added in too great a percentage.
+
+The use of hardened oils is not yet general, but there is little doubt
+that the introduction of this process goes a long way toward solving the
+problem of cheaper soap material for the soap making industry.
+
+
+GREASE.
+
+Grease varies so greatly in composition and consistency that it can
+hardly be classed as a distinctive oil or fat. It is obtained from
+refuse, bones, hides, etc., and while it contains the same constituents
+as tallow, the olein content is considerably greater, which causes it to
+be more liquid in composition. Grease differs in color from an off-white
+to a dark brown. The better qualities are employed in the manufacture of
+laundry and chip soap, while the poorer qualities are only fit for the
+cheapest of soaps used in scrubbing floors and such purposes. There is
+usually found in grease a considerable amount of gluey matter, lime and
+water. The percentage of free fatty acid is generally high.
+
+The darker grades of grease are bleached before being used. This is done
+by adding a small quantity of sodium nitrate to the melted grease and
+agitating, then removing the excess saltpeter by decomposing with
+sulphuric acid. A better method of refining, however, is by
+distillation. The chrome bleach is also applicable.
+
+
+ROSIN (COLOPHONY, YELLOW ROSIN, RESINA).
+
+Rosin is the residue which remains after the distillation of turpentine
+from the various species of pines. The chief source of supply is in the
+States of Georgia North and South Carolina. It is a transparent, amber
+colored hard pulverizable resin. The better grades are light in color
+and known as water white (w. w.) and window glass (w. g.). These are
+obtained from a tree which has been tapped for the first year. As the
+same trees are tapped from year to year, the product becomes deeper and
+darker in color until it becomes almost black.
+
+The constituents of rosin are chiefly (80-90%) abietic acid or its
+anhydride together with pinic and sylvic acids. Its specific gravity is
+1.07-1.08, melting point about 152.5 C., and it is soluble in alcohol,
+ether, benzine, carbon disulfide, oils, alkalis and acetic acid. The
+main use of rosin, outside of the production of varnishes, is in the
+production of laundry soaps, although a slight percentage acts as a
+binder and fixative for perfumes in toilet soaps and adds to their
+detergent properties. Since it is mainly composed of acids, it readily
+unites with alkaline carbonates, though the saponification is not quite
+complete and the last portion must be completed through the use of
+caustic hydrates, unless an excess of 10% carbonate over the theoretical
+amount is used. A lye of 20deg. B. is best adapted to the saponification of
+rosin when caustic hydrates are employed for this purpose, since weak
+lyes cause frothing. While it is sometimes considered that rosin is an
+adulterant for soap, this is hardly justifiable, as it adds to the
+cleansing properties of soap. Soaps containing rosin are of the well
+known yellowish color common to ordinary laundry soaps. The price of
+rosin has so risen in the last few years that it presents a problem of
+cost to the soap manufacturer considering the price at which laundry
+soaps are sold.
+
+
+ROSIN SAPONIFICATION.
+
+As has been stated, rosin may be saponified by the use of alkaline
+carbonates. On account of the possibility of the soap frothing over, the
+kettle in which the operation takes place should be set flush with the
+floor, which ought to be constructed of cement. The kettle itself is an
+open one with round bottom, equipped with an open steam coil and skimmer
+pipe, and the open portion is protected by a semi-circular rail. A
+powerful grid, having a 3-inch mesh, covers one-half of the kettle, the
+sharp edges protruding upwards.
+
+The staves from the rosin casks are removed at the edge of the kettle,
+the rosin placed on the grid and beaten through with a hammer to break
+it up into small pieces.
+
+To saponify a ton of rosin there are required 200 lbs. soda ash, 1,600
+lbs. water and 100 lbs. salt. Half the water is run into the kettle,
+boiled, and then the soda ash and half the salt added. The rosin is now
+added through the grid and the mixture thoroughly boiled. As carbon
+dioxide is evolved by the reaction the boiling is continued for one hour
+to remove any excess of this gas. A portion of the salt is gradually
+added to grain the soap well and to keep the mass in such condition as
+to favor the evolution of gas. The remainder of the water is added to
+close the soap and boiling continued for one or two hours longer. At
+this point the kettle must be carefully watched or it will boil over
+through the further escape of carbon dioxide being hindered. The mass,
+being in a frothy condition, will rapidly settle by controlling the flow
+of steam. The remaining salt is then scattered in and the soap allowed
+to settle for two hours or longer. The lyes are then drained off the
+top. If the rosin soap is required for toilet soaps, it is grained a
+second time. The soap is now boiled with the water caused by the
+condensation of the steam, which changes it to a half grained soap
+suitable for pumping. A soap thus made contains free soda ash 0.15% or
+less, free rosin about 15%. The mass is then pumped to the kettle
+containing the soap to which it is to be added at the proper stage. The
+time consumed in thus saponifying rosin is about five hours.
+
+
+NAPHTHENIC ACIDS.
+
+The naphtha or crude petroleum of the various provinces in Europe, as
+Russia, Galacia, Alsace and Roumania yield a series of bodies of acid
+character upon refining which are designated under the general name of
+naphthenic acids. These acids are retained in solution in the alkaline
+lyes during the distillation of the naphtha in the form of alkaline
+naphthenates. Upon adding dilute sulphuric acid to these lyes the
+naphthenates are decomposed and the naphthenic acids float to the
+surface in an oily layer of characteristic disagreeable odor and varying
+from yellow to brown in color[7]. In Russia particularly large
+quantities of these acids are employed in the manufacture of soap.
+
+The soaps formed from naphthenic acids have recently been
+investigated[8] and found to resemble the soaps made from cocoanut oil
+and palm kernel oil, in that they are difficult to salt out and
+dissociate very slightly with water. The latter property makes them
+valuable in textile industries when a mild soap is required as a
+detergent, e. g., in the silk industry. These soaps also possess a high
+solvent power for mineral oils and emulsify very readily. The mean
+molecular weight of naphthenic acids themselves is very near that of the
+fatty acids contained in cocoanut oil, and like those of cocoanut oil a
+portion of the separated acids are volatile with steam. The iodine
+number indicates a small content of unsaturated acids.
+
+That naphthenic acids are a valuable soap material is now recognized,
+but except in Russia the soap is not manufactured to any extent at the
+present time.
+
+
+ALKALIS.
+
+The common alkali metals which enter into the formation of soap are
+sodium and potassium. The hydroxides of these metals are usually used,
+except in the so called carbonate saponification of free fatty acids in
+which case sodium and potassium carbonate are used. A water solution of
+the caustic alkalis is known as lye, and it is as lyes of various
+strengths that they are added to oils and fats to form soap. The density
+or weight of a lye is considerably greater than that of water, depending
+upon the amount of alkali dissolved, and its weight is usually
+determined by a hydrometer. This instrument is graduated by a
+standardized scale, and while all hydrometers should read alike in a
+liquid of known specific gravity, this is generally not the case, so
+that it is advisable to check a new hydrometer for accurate work against
+one of known accuracy. In this country the Baume scale has been adopted,
+while in England a different graduation known as the Twaddle scale is
+used. The strength of a lye or any solution is determined by the
+distance the instrument sinks into the solution, and we speak of the
+strength of a solution as so many degrees Baume or Twaddle which are
+read to the point where the meniscus of the lye comes on the graduated
+scale. Hydrometers are graduated differently for liquids of different
+weights. In the testing of lyes one which is graduated from 0deg. to
+50deg. B. is usually employed.
+
+_Caustic soda_ is received by the consumer in iron drums weighing
+approximately 700 lbs. each. The various grades are designated as 60,
+70, 74, 76 and 77%. These percentages refer to the percentage of sodium
+oxide (Na_{2}O) in 100 parts of pure caustic soda formed by the
+combination of 77-1/2 parts of sodium oxide and 22-1/2 parts of water,
+77-1/2% being chemically pure caustic soda. There are generally
+impurities present in commercial caustic soda. These consist of sodium
+carbonate, sodium chloride or common salt and sometimes lime. It is
+manufactured by treating sodium carbonate in an iron vessel with calcium
+hydroxide or slaked lime, or by electrolysis of common salt. The latter
+process has yet been unable to compete with the former in price.
+Formerly all the caustic soda used in soap making was imported, and it
+was only through the American manufacturer using a similar container to
+that used by foreign manufacturers that they were able to introduce
+their product. This prejudice has now been entirely overcome and most of
+the caustic soda used in this country is manufactured here.
+
+
+CAUSTIC POTASH.
+
+The output of the salts containing potassium is controlled almost
+entirely by Germany. Formerly the chief source of supply of potassium
+compounds was from the burned ashes of plants, but about fifty years ago
+the inexhaustible salt mines of Stassfurt, Germany, were discovered.
+The salt there mined contains, besides the chlorides and sulphates of
+sodium, magnesium, calcium and other salts, considerable quantities of
+potassium chloride, and the Stassfurt mines at present are practically
+the entire source of all potassium compounds, in spite of the fact that
+other localities have been sought to produce these compounds on a
+commercial basis, especially by the United States government.
+
+After separating the potassium chloride from the magnesium chloride and
+other substances found in Stassfurt salts the methods of manufacture of
+caustic potash are identical to those of caustic soda. In this case,
+however, domestic electrolytic caustic potash may be purchased cheaper
+than the imported product and it gives results equal to those obtained
+by the use of the imported article, opinions to the contrary among soap
+makers being many. Most of the caustic potash in the United States is
+manufactured at Niagara Falls by the Niagara Alkali Co., and the Hooker
+Electrochemical Co., chlorine being obtained as a by-product. The latter
+concern employs the Townsend Cell, for the manufacture of electrolytic
+potash, and are said to have a capacity for making 64 tons of alkali
+daily.
+
+Since the molecular weight of caustic potash (56) is greater than that
+of caustic soda (40) more potash is required to saponify a pound of fat.
+The resulting potash soap is correspondingly heavier than a soda soap.
+When salt is added to a potassium soap double decomposition occurs, the
+potassium soap being transformed to a sodium soap and the potassium
+uniting with the chlorine to form potassium chloride. This was one of
+the earliest methods of making a hard soap, especially in Germany, where
+potash was derived from leeching ashes of burned wood and plants.
+
+
+SODIUM CARBONATE (SODA ASH).
+
+While carbonate of soda is widely distributed in nature the source of
+supply is entirely dependent upon the manufactured product. Its uses are
+many, but it is especially important to the soap industry in the so
+called carbonate saponification of free fatty acids, as a constituent of
+soap powders, in the neutralization of glycerine lyes and as a filler
+for laundry soaps.
+
+The old French Le Blanc soda process, which consists in treating common
+salt with sulphuric acid and reducing the sodium sulphate (salt cake)
+thus formed with carbon in the form of charcoal or coke to sodium
+sulphide, which when treated with calcium carbonate yields a mixture of
+calcium sulphide and sodium carbonate (black ash) from which the
+carbonate is dissolved by water, has been replaced by the more recent
+Solvay ammonia soda process. Even though there is a considerable loss of
+salt and the by-product calcium chloride produced by this process is
+only partially used up as a drying agent, and for refrigerating
+purposes, the Le Blanc process cannot compete with the Solvay process,
+so that the time is not far distant when the former will be considered a
+chemical curiosity. In the Solvay method of manufacture sodium chloride
+(common salt) and ammonium bicarbonate are mixed in solution. Double
+decomposition occurs with the formation of ammonium chloride and sodium
+bicarbonate. The latter salt is comparatively difficultly soluble in
+water and crystallizes out, the ammonium chloride remaining in solution.
+When the sodium bicarbonate is heated it yields sodium carbonate, carbon
+dioxide and water; the carbon dioxide is passed into ammonia which is
+set free from the ammonium chloride obtained as above by treatment with
+lime (calcium oxide) calcium chloride being the by-product.
+
+Sal soda or washing soda is obtained by recrystallizing a solution of
+soda ash in water. Large crystals of sal soda containing but 37% sodium
+carbonate are formed.
+
+
+POTASSIUM CARBONATE.
+
+Potassium carbonate is not extensively used in the manufacture of soap.
+It may be used in the forming of soft soaps by uniting it with free
+fatty acids. The methods of manufacture are the same as for sodium
+carbonate, although a much larger quantity of potassium carbonate than
+carbonate of soda is obtained from burned plant ashes. Purified
+potassium carbonate is known as _pearl ash_.
+
+
+ADDITIONAL MATERIAL USED IN SOAP MAKING.
+
+Water is indispensable to the soap manufacturer. In the soap factory
+_hard_ water is often the cause of much trouble. Water, which is the
+best solvent known, in passing through the crevices of rocks dissolves
+some of the constituents of these, and the water is known as hard. This
+hardness is of two kinds, _temporary_ and _permanent_. Temporarily hard
+water is formed by water, which contains carbonic acid, dissolving a
+portion of calcium carbonate or carbonate of lime. Upon boiling, the
+carbonic acid is driven from the water and the carbonate, being
+insoluble in carbon dioxide free water, is deposited. This is the cause
+of boiler scale, and to check this a small amount of sal ammoniac may be
+added to the water, which converts the carbonate into soluble calcium
+chloride and volatile ammonium carbonate. Permanent hardness is caused
+by calcium sulphate which is soluble in 400 parts of water and cannot be
+removed by boiling.
+
+The presence of these salts in water form insoluble lime soaps which act
+as inert bodies as far as their value for the common use of soap is
+concerned. Where the percentage of lime in water is large this should be
+removed. A method generally used is to add about 5% of 20deg. B. sodium
+silicate to the hard water. This precipitates the lime and the water is
+then sufficiently pure to use.
+
+_Salt_, known as sodium chloride, is used to a large extent in soap
+making for "salting out" the soap during saponification, as well as
+graining soaps. Soap ordinarily soluble in water is insoluble in a salt
+solution, use of which is made by adding salt to the soap which goes
+into solution and throws any soap dissolved in the lyes out of solution.
+Salt may contain magnesium and calcium chlorides, which of course are
+undesirable in large amounts. The products on the market, however, are
+satisfactory, thus no detail is necessary.
+
+_Filling materials_ used are sodium silicate, or water glass, talc,
+silex, pumice, starch, borax, tripoli, etc.
+
+Besides these other materials are used in the refining of the oils and
+fats, and glycerine recovery, such as Fuller's earth, bichromates of
+soda or potash, sulphate of alumina, sulphuric and hydrochloric acids
+and alcohol.
+
+A lengthy description of these substances is not given, as their modes
+of use are detailed elsewhere.
+
+FOOTNOTES:
+
+[1] Seifensieder Zeit, 1913, 40, p. 687, 724, 740.
+
+[2] Official Methods, see Bull. 107, A. O. A. C., U. S. Dept. Agricult.
+
+[3] Journ. Coll. of Engin. Tokyo Imper. Univ. (1906), p. 1. Abs. Chem.
+Revue f. d. Fett-u. Harz, Ind. 16, p. 84; 20, p. 8.
+
+[4] Meyerheim--Fort. der Chem., Physik. und Physik. Chem. (1913), 8. 6,
+p. 293-307.
+
+[5] Seifs. Ztg. (1913), 40, p. 142.
+
+[6] Loc. cit.
+
+[7] Les Matieres Graisses (1914), 7, 69, p. 3367.
+
+[8] Zeit. f. Angew. Chem. (1914), 27, 1, p. 2-4.
+
+
+
+
+CHAPTER II
+
+Construction and Equipment of a Soap Plant.
+
+
+No fixed plan for the construction and equipment of a soap plant can be
+given. The specifications for a soap factory to be erected or remodeled
+must suit the particular cases. Very often a building which was
+constructed for a purpose other than soap manufacture must be adapted
+for the production of soap. In either case it is a question of
+engineering and architecture, together with the knowledge obtained in
+practice and the final decision as to the arrangement is best solved by
+a conference with those skilled in each of these branches.
+
+An ideal soap plant is one in which the process of soap making, from the
+melting out of the stock to the packing and shipping of the finished
+product, moves downward from floor to floor, since by this method it is
+possible to utilize gravitation rather than pumping liquid fats and
+fluid soaps. Convenience and economy are obtained by such an
+arrangement.
+
+The various machinery and other equipment for soap manufacture are well
+known to those connected with this industry. It varies, of course,
+depending upon the kind of soap to be manufactured, and full
+descriptions of the necessary machinery are best given in the catalogs
+issued by the manufacturers of such equipment, who in this country are
+most reliable.
+
+To know just what equipment is necessary can very easily be described by
+a brief outline of the process various soaps undergo to produce the
+finished article. After the saponification has taken place in the _soap
+kettle_ the molten soap is run directly into the soap _frames_, which
+consist of an oblong compartment, holding anywhere from 400 to 1,200
+pounds, with removable steel sides and mounted upon trucks, in which it
+solidifies. In most cases it is advisable to first run the soap into a
+_crutcher_ or mixer which produces a more homogeneous mass than if this
+operation is omitted. Color and perfume may also be added at this point,
+although when a better grade of perfume is added it must be remembered
+that there is considerable loss due to volatilization of same. When a
+_drying machine_ is employed the molten soap is run directly upon the
+rollers of this machine, later adding about 1.0% zinc oxide to the soap
+from which it passes continuously through the drying chamber and is
+emitted in chip form ready for milling. After the soap has been framed,
+it is allowed to cool and solidify, which takes several days, and then
+the sides of the frame are stripped off. The large solid cake is cut
+with wires by hand or by a _slabber_ into slabs of any desired size.
+These slabs are further divided into smaller divisions by the _cutting
+table_. In non-milled soaps (laundry soaps, floating soaps, etc.), these
+are pressed at this stage, usually by automatic presses, after a thin
+hard film has been formed over the cake by allowing it to dry slightly.
+In making these soaps they are not touched by hand at any time during
+the operation, the pressing, wrapping and packing all being done by
+machinery. For a milled soap the large slabs are cut into narrow oblong
+shapes by means of the cutting table to readily pass into the feeder of
+the _chipper_, the chips being spread upon _trays_ and dried in a _dry
+house_ until the moisture content is approximately 15%.
+
+The process of milling is accomplished by passing the dried soap chips
+through a _soap mill_, which is a machine consisting of usually three or
+four contiguous, smooth, granite rollers operated by a system of gears
+and set far enough apart to allow the soap to pass from a hopper to the
+first roller, from which it is constantly conveyed to each succeeding
+roller as a thin film, and finally scraped from the last roller to fall
+into the _milling box_ in thin ribbon form. These mills are often
+operated in tandem, which necessitates less handling of soap by the
+operator. The object of milling is to give the soap a glossy, smooth
+finish and to blend it into a homogeneous mass. The perfume, color,
+medication or any other material desired are added to the dried soap
+chips prior to milling. Some manufacturers use an _amalgamator_ to
+distribute these uniformly through the soap, which eliminates at least
+one milling. When a white soap is being put through the mill, it is
+advisable to add from 0.5% to 1% of a good, fine quality of zinc oxide
+to the soap, if this substance has not been previously added. This
+serves to remove the yellowish cast and any translucency occasioned by
+plodding. Too great a quantity of this compound added, later exhibits
+itself by imparting to the soap a dead white appearance. Inasmuch as the
+milling process is one upon which the appearance of a finished cake of
+toilet soap largely depends, it should be carefully done. The number of
+times a soap should be milled depends upon the character of a soap being
+worked. It should of course be the object to mill with as high a
+percentage of moisture as possible. Should the soap become too dry it is
+advisable to add water directly, rather than wet soap, since water can
+more easily be distributed through the mass. As a general statement it
+may be said it is better policy to overmill a soap, rather than not mill
+it often enough.
+
+After the soap has been thoroughly milled it is ready for plodding. A
+_plodder_ is so constructed as to take the soap ribbons fed into the
+hopper by means of a worm screw and continuously force it under great
+pressure through a jacketed cylinder through which cold water circulates
+in the rear to compensate the heat produced by friction and hot water at
+the front, to soften and polish the soap which passes out in solid form
+in bars of any shape and size depending upon the form of the _shaping
+plate_ through which it is emitted. The bars run upon a _roller board_,
+are cut into the required length by a special _cake cutting table_,
+allowed to dry slightly and pressed either automatically or by a foot
+power _press_ in any suitable soap _die_. The finished cake is then
+ready for wrapping and after due time in stock reaches the consumer.
+
+Besides the various apparatus mentioned above there are many other parts
+for the full equipment of a modern soap plant, such as remelters, pumps,
+mixers, special tanks, power equipment, etc. As has been stated,
+however, practical experience will aid in judging the practicability as
+to installation of these. The various methods of powdering soap are,
+however, not generally known. Where a coarse powder is to be produced,
+such as is used for common washing powders, no great difficulty is
+experienced with the well known Blanchard mill. In grinding soap to an
+impalpable powder the difficulties increase. The methods adapted in
+pulverizing soaps are by means of disintegrators, pebble mills and
+chaser mills. The disintegrator grinds by the principle of attrition,
+that is, the material is reduced by the particles being caused to beat
+against each other at great velocity; a pebble mill crushes the
+substance by rubbing it between hard pebbles in a slowly revolving
+cylinder; the chaser mill first grinds the material and then floats it
+as a very fine powder above a curb of fixed height. The last method is
+particularly adapted for the finest of powder (140 mesh and over).
+
+
+
+
+CHAPTER III
+
+Classification of Soap-Making Methods.
+
+
+In the saponification of fats and oils to form soap through the agency
+of caustic alkalis, as has been stated, the sodium or potassium salts of
+the mixed fatty acids are formed. Sodium soaps are usually termed hard
+soaps, and potassium soaps soft. There are, however, a great many
+varieties of soaps the appearance and properties of which depend upon
+their method of manufacture and the oils or fats used therein.
+
+The various methods adopted in soap making may be thus classified:
+
+1. Boiling the fats and oils in open kettles by open steam with
+indefinite quantities of caustic alkali solutions until the finished
+soap is obtained; ordinarily named _full boiled soaps_. These may be
+sub-divided into (a) hard soaps with sodium hydrate as a base, in which
+the glycerine is recovered from the spent lyes; (b) hard soaps with soda
+as a base, in which the glycerine remains in the soap, e. g., marine
+cocoanut oil soaps; (c) soft potash soaps, in which the glycerine is
+retained by the soap.
+
+2. Combining the required amount of lye for complete saponification of a
+fat therewith, heating slightly with dry heat and then allowing the
+saponification to complete itself. This is known as the _cold process_.
+
+3. Utilizing the fatty acid, instead of the neutral fat, and combining
+it directly with caustic alkali or carbonate, which is incorrectly
+termed _carbonate saponification_, since it is merely neutralizing the
+free fatty acid and thus is not a saponification in the true sense of
+the word. No glycerine is directly obtained by this method, as it is
+usually previously removed in the clearage of the fat by either the
+Twitchell or autoclave saponification method.
+
+In the methods thus outlined the one most generally employed is the full
+boiled process to form a sodium soap. This method of making soap
+requires close attention and a knowledge which can only be obtained by
+constant practice. The stock, strength of lyes, heat, amount of salt or
+brine added, time of settling, etc., are all influencing factors.
+
+The principles involved in this process are briefly these:
+
+The fat is partly saponified with weak lyes (usually those obtained from
+a previous boiling in the strengthening change are used), and salt is
+added to grain the soap. The mass is then allowed to settle into two
+layers. The upper layer is partly saponified fat; the lower layer, or
+spent lye, is a solution of salt, glycerine, and contains any albuminous
+matter or any other impurity contained in the fat. This is known as the
+_killing_ or glycerine change. Strong lyes are now added and the fat
+entirely saponified, which is termed the _strengthening change_. The
+mass is then allowed to settle and the fluid soap run off above the
+"nigre." This operation is called the finish or _finishing_ change.
+
+The method may be more fully illustrated by a concrete example of the
+method of manufacture of a tallow base:
+
+    Charge--
+
+    Tallow              88 per cent.
+    Cocoanut oil        10 per cent.
+    Rosin w. w.          2 per cent.
+
+        Amount charge   10 tons
+
+About five tons of tallow and one ton of cocoanut oil are pumped or run
+into the soap kettle and brought to a boil with wet steam until it
+briskly comes through the hot fat. The caustic soda (strengthening lyes
+from former boilings may be used here) is gradually added by the
+distributing pipe, any tendency to thicken being checked by the
+introduction of small quantities of brine ("salt pickle"). If the lye is
+added too rapidly the soap assumes a granular appearance, indicating
+that the addition of same must be discontinued. Water should then be
+added and the mass boiled through until it again closes. When the
+addition of the proper amount of caustic soda is nearing its completion
+the soap gradually thins. The steam is now cut down to about one turn of
+the valve, and brine is rapidly added or salt shoveled in. In ten to
+fifteen minutes the steam again breaks through and, from the appearance
+of the soap, it can be seen whether sufficient brine has been added. A
+sample taken out by means of a long wooden paddle should show the soap
+in fine grains with the lyes running from it clear. The steam is then
+shut off and the soap allowed to settle from one and one-half to two
+hours. In all settlings the longer time this operation is permitted to
+continue, the better will the subsequent operations proceed.
+
+The mixture now consists of a partly saponified layer of fat above the
+spent lyes. The lyes are drawn off until soap makes its appearance at
+the exit pipe. The valve is then closed and the soap blown back into the
+kettle by steam. The lyes thus obtained are known as _spent lyes_, from
+which the glycerine is recovered. They should show an alkalinity of
+approximately 0.5 per cent. if the operation is carefully carried out.
+
+The remaining tallow is now added and the above operations repeated.
+
+After the spent lyes have been drawn off, the soap is closed with water
+and the proper percentage of rosin soap previously formed, or rosin
+itself is added to the mass in the kettle. More lye is then allowed to
+flow in until the mixture is up to "strength." This is usually tested
+by the "bite" on the tongue of a small cooled sample. After boiling
+until the steam comes through, the mass is grained with salt as before
+and allowed to settle one and one-half to three hours. These lyes, known
+as _strengthening lyes_ are run to storage to be used subsequently with
+fresh fat to take up the caustic soda contained therein.
+
+The soap is now ready for finishing and is first boiled through and
+tried for strength. A drop of phenolphthalein (1 per cent.
+phenolphthalein in 98 per cent. alcohol) is allowed to drop on the
+molten soap taken up on a trowel. The red color should be instantly
+produced and develop to a full deep crimson in a few seconds, or more
+lye must be added until this condition is realized. Should it flash a
+deep crimson immediately it is on the strong side. This cannot be
+conveniently remedied; it can only serve as a guide for the next boil,
+but in any case it is not of any serious consequence, unless it is too
+strong.
+
+With the steam on, the soap is now examined with a trowel which must be
+thoroughly heated by working it about under the surface of the hot soap.
+The appearance of the soap as it runs from the face of the trowel
+indicates its condition. It is not possible to absolutely describe the
+effect, which can only be properly judged by practice, yet the following
+points may serve as a guide. The indications to be noticed are the shape
+and size of the flakes of soap as the sample on the trowel breaks up and
+runs from the hot iron surface, when the latter is turned in a vertical
+position, as well as the condition of the iron surface from which the
+soap flakes have fallen. A closed soap will run slowly into a
+homogeneous sheet, leaving the trowel's surface covered with a thin
+layer of transparent soap; a grained mass will run rapidly down in tiny
+grains, about one-half an inch in diameter or less, leaving the hot
+trowel absolutely dry. The object of the finish is to separate the
+soaps of the lower fatty acids from those of the higher, and both from
+excess of liquid. A point midway between "open" and "closed" is required
+to arrive at this point.
+
+Having arrived at the above condition, the soap is allowed to settle
+anywhere from one to three days and then run off through the skimmer
+pipes to the nigre and framed or pumped to the tank feeding the drying
+machine.
+
+The stock thus obtained should be fairly white, depending upon the grade
+of tallow used and slightly alkaline to an alcoholic phenolphthalein
+solution. If removed at exactly the neutral point or with a content of
+free fat the soap will sooner or later develop rancidity. The soap thus
+obtained is an ordinary tallow base, and the one by far greatest used in
+the manufacture of toilet soaps. The percentage of cocoanut oil
+indicated is not fixed and may readily be varied, while in fine toilet
+soap the rosin is usually eliminated.
+
+In the manufacture of full boiled soda soaps in which no glycerine is
+obtained as a by-product, it being retained in the soap itself, the soap
+formed is known as a "run" soap. The process is used most extensively in
+the manufacture of marine soaps by which the method may be best
+illustrated. This soap is known as marine soap because of its property
+of readily forming a lather with salt water and is mostly consumed
+aboard vessels.
+
+Marine soaps are manufactured by first placing in the kettle a
+calculated amount of lye of 25 deg. to 35 deg. B., depending upon the
+amount of moisture desired in the finished soaps, plus a slight excess
+required to saponify a known weight of cocoanut oil. With open steam on,
+the cocoanut oil is then gradually added, care being taken that the soap
+does not froth over. Saponification takes place readily and when the oil
+is entirely saponified the finished soap is put through the process
+known as running. This consists in constantly pumping the mass from the
+skimmer pipe back into the top of the kettle, the object being to
+prevent any settling of the nigre or lye from the soap, as well as
+producing a homogeneous mass. It is customary to begin the
+saponification in the morning, which should be completed by noon. The
+soap is then run for about three hours and framed the next morning.
+After having remained in the frame the time required to solidify and
+cool, the soap is slabbed and cut into cakes. This process is difficult
+to carry out properly, and one not greatly employed, although large
+quantities of marine soap are purchased by the government for use in the
+navy and must fulfill certain specifications required by the purchasing
+department.
+
+In making potash soaps it is practically impossible to obtain any
+glycerine directly because of the pasty consistency of the soap, and no
+graining is possible because the addition of salt to a soft soap, as
+already explained, would form a soda soap. Large quantities of soft
+soaps are required for the textile industries who desire mostly a strong
+potash soap, and the large number of automobiles in use at the present
+time has opened a field for the use of a soft soap for washing these. A
+soap for this purpose must be neutral so as not to affect the varnish or
+paint of automobiles.
+
+A suitable soap for textile purposes may be made as follows:
+
+    Red oil                         80     parts
+    House grease                    20     parts
+    Caustic soda lye, 36 degs. B.    3     parts
+    Carbonate of potash              5-1/2 parts
+    Caustic potash                  23-1/4 parts
+
+Olive oil, corn oil, soya bean oil, olive oil foots or cottonseed oil
+may replace any of the above oils. A large quantity of cottonseed oil
+will cause the soap to fig.
+
+To carry out the process, the caustic potash and carbonate of potash are
+dissolved and placed in the kettle together with the soda lye, and the
+oils added. This is most satisfactorily accomplished by being finished
+the day before the boiling is begun. The next day the boiling is begun
+and water added to bring the soap up to the desired percentage of fatty
+acid, due allowance being made for the water formed by the condensation
+of the open steam in boiling. Care must be taken that the soap in the
+kettle does not swell and run over during the saponification. A good
+procedure is to use open steam for a period of about two hours, then
+close the valve and allow the saponification to continue without
+boiling, and repeat this until it is entirely saponified. After the
+saponification has been completed the soap is briskly boiled all day and
+the proper corrections made; that is, if too alkaline, more oil is
+added, and if free fat is present, more potash. About 2 per cent.
+carbonate of potash is the proper amount for a soap containing 50 per
+cent. fatty acid. The soap is sampled by allowing it to drop on a clean,
+cold glass surface. In so doing, the soap should not slide or slip over
+the glass surface when pressed thereon, but should adhere to the glass,
+or it is too alkaline. A sample worked between the fingers showing too
+much stringiness should have more strong potash and oil added. A sample
+taken out in a pail and allowed to cool over night will serve as a guide
+as to the body of the soap in the kettle. When the soap has thus been
+properly finished it is run into barrels.
+
+For an automobile soap the following is a good working formula:
+
+    Corn oil                       1,000 parts
+    Potash lye, 31-1/2 degs. B.      697 parts
+
+Proceed as in the directions just given for textile soap in placing
+charge in the kettle. When the kettle is boiling up well, shut off the
+steam and the saponification will complete itself. The soap may be run
+into the barrels the next day.
+
+A heavy soap with a smaller percentage of fat may be made as follows:
+
+    Corn oil                       1,000 parts
+    Potash lye, 24-1/2 degs. B.      900 parts
+
+Boil until the soap bunches, and shovel the finished soap into barrels.
+Upon standing it will clear up. By the addition of more water the yield
+of soap per pound of oil may be run up to 300 per cent.
+
+After soft soaps have been allowed to stand for some time the phenomenon
+known as "figging" often occurs. This term is applied to a
+crystalline-like formation, causing spots of a star-like shape
+throughout the soap. This is undoubtedly due to the stearine content of
+the soap crystallizing out as it cools, and forming these
+peculiarly-shaped spots. It more generally occurs in the winter and may
+be produced artificially by adding a small quantity of soda to the
+potash lye before saponification.
+
+The oils usually employed in the manufacture of potash soaps are
+cottonseed oil, corn oil, soya bean oil, olive oil foots, red oil,
+cocoanut oil, grease and the various train oils. The usual percentage
+yield is from 225 per cent. to 300 per cent., based upon the weight of
+oil used. In calculating the weight of a soft soap it is to be
+remembered that since potassium has a higher molecular weight (56) than
+sodium (40), the corresponding soap formed is that much greater in
+weight when compared with a sodium soap. Rosin may be added to soft
+soaps as a cheapening agent.
+
+
+COLD PROCESS.
+
+The cold process for manufacturing soap is the simplest method of soap
+making, and the equipment required is small when compared to the other
+methods. All the more expensive equipment that is necessary is a
+crutcher, a tank to hold the lye, frames, a slabber or cutting table,
+and a press. Yet, in spite of the simplicity of thus making soap, the
+disadvantages are numerous for the production of a good piece of soap.
+The greatest difficulty is to obtain a thorough combination of oil or
+fat and lye so that there will not be an excess of one or the other in
+the finished soap. At its best there is either a considerable excess of
+free fat which later exhibits itself in producing rancidity or
+uncombined caustic, which produces an unpleasant effect on the skin when
+the soap is consumed for washing. The latter objection, of course, can
+only be applied to toilet soaps.
+
+Cocoanut oil is used very largely in the manufacture of cold-made soaps
+as it is well adapted for this purpose, although it is by no means true
+that other oils may not be employed. Since by this process of
+manufacture no impurity contained in the fat or oil is removed in the
+making of the soap, it is necessary that in order to obtain a fine
+finished product, any impurity contained in these may be removed if
+present, or that the fats be as pure as can be obtained. If inedible
+tallow is used for cold-made soap, it is advisable to bleach it by the
+Fuller's Earth Process.
+
+The carrying out of this method is best illustrated by an example of a
+cold-made cocoanut oil soap.
+
+    Charge:
+
+    Cochin cocoanut oil          846 parts
+    Lye (soda), 35 degs. B.      470 parts
+    Water                         24 parts
+
+The oil is run into the crutcher and the temperature of the oil raised
+to 100 degs. F. by dry steam. The lye and water are at room temperature.
+After all the oil is in the crutcher, the lye and water are slowly added
+to prevent any graining of the soap. Toward the end the lye may be added
+more rapidly. When all the lye is in, the mass is crutched for about
+three hours, or until upon stopping the crutcher a finger drawn over the
+surface of the soap leaves an impression. If this condition is not
+realized, the soap must be mixed until such is the case. Having arrived
+at this point, the mixture is dropped into a frame which should remain
+uncovered. The heat produced by the further spontaneous saponification
+will cause the soap to rise in the middle of the frame. After having set
+for some days it is ready to be slabbed and cut into cakes.
+
+A potash soap may be made by the cold process just as readily as a soda
+soap. Soaps of this type may be made by either of these formulae in a
+crutcher:
+
+    Olive oil foots                                  600
+    Potash lye, 18 degs. B. hot, 20 degs. B. cold    660
+
+                    or
+
+    Corn oil                                         800
+    Rosin                                            200
+    Potash lye, 27 degs. B.                          790
+    Water                                            340
+
+Heat the oils to 190 degs. F., add the lye and crutch until the soap
+begins to bunch, when it is ready to be run into barrels where the
+saponification will be completed.
+
+Semi-boiled soaps differ from those made by the cold process in
+temperature. In making semi-boiled soaps the fats are usually heated to
+140deg. F. The addition of the lye raises the temperature to
+180deg.--200deg. F. when saponification takes place.
+
+
+CARBONATE SAPONIFICATION.
+
+The method of the formation of soap by the utilization of the fatty acid
+directly, from which the glycerine has already been removed by some
+method of saponification other than with caustic soda, and neutralizing
+this with alkali, is becoming increasingly popular. The glycerine is
+more easily recovered from a previous cleavage of the fats or oils, but
+a soap made from the mixed fatty acids thus obtained is seldom white in
+color and retains an unpleasant odor. Since soda ash or sodium carbonate
+is cheaper than caustic soda and readily unites with a fatty acid, it is
+used as the alkali in the carbonate saponification. The process is
+similar to that already given under Rosin Saponification. About 19 per
+cent. by weight of the fatty acids employed of 58 per cent. soda ash is
+dissolved in water until it has a density of 30 degs. B., and the
+solution is run into the kettle, which is usually equipped with a
+removable agitator. The fatty acids, previously melted, are then slowly
+added while the mixture is boiled with open steam and agitated with the
+stirring device. The fatty acids instantly unite with the carbonate and
+rise in the kettle, due to the generation of carbon dioxide, and care
+must be exercised to prevent boiling over. After all the fatty acid has
+been added, and the mass is boiled through the saponification must be
+completed with caustic soda, as there is as yet no practical method
+known which will split a fat entirely into fatty acid and glycerine.
+Thus about 10 per cent. of the fatty acids are true neutral fats and
+require caustic soda for their saponification. This is then added and
+the soap completed, as in full-boiled soaps.
+
+In carrying out this method upon a large scale, large
+sue\Neanderthal\doroteer\Neanderthal\Josephine\ quantities of carbon
+dioxide are formed during the boiling of the soap, which replaces a
+quantity of the air contained therein. The kettle room should therefore
+be well ventilated, allowing for a large inflow of fresh air from out of
+doors.
+
+
+
+
+CHAPTER IV
+
+Classification of Soaps.
+
+
+In considering the many different varieties of soaps, their
+classification is purely an arbitrary one. No definite plan can be
+outlined for any particular brand to be manufactured nor can any very
+sharp distinction be drawn between the many soaps of different
+properties which are designated by various names. It is really a
+question to what use a soap is to be put, and at what price it may be
+sold. There is, of course, a difference in the appearance, form and
+color, and then there are soaps of special kinds, such as floating
+soaps, transparent soaps, liquid soaps, etc., yet in the ultimate sense
+they are closely allied, because they are all the same chemical
+compound, varying only in their being a potash or soda soap, and in the
+fatty acids which enter into combination with these alkalis. Thus we can
+take a combination of tallow and cocoanut oil and make a great many
+presumably different soaps by combining these substances with caustic
+soda, by different methods of manufacture and by incorporating various
+other ingredients, as air, to form a floating soap, alcohol to make a
+transparent soap, dyestuffs to give a different color, etc., but
+essentially it is the same definite compound.
+
+The manufacturer can best judge the brand of soaps he desires to
+manufacture, and much of his success depends upon the name, package,
+shape, color or perfume of a cake of soap. It is the consumer whom he
+must please and many of the large selling brands upon the market today
+owe their success to the above mentioned details. The great majority of
+consumers of soap know very little concerning soap, except the fact
+that it washes or has a pleasant odor or looks pretty, and the
+manufacturer of soap must study these phases of the subject even more
+carefully than the making of the soap itself.
+
+For a matter of convenience we will classify soap under three general
+divisions:
+
+I. Laundry soaps, including chip soaps, soap powders and scouring soaps.
+
+II. Toilet soaps, including floating soap, castile soap, liquid soap,
+shaving soap, etc.
+
+III. Textile soaps.
+
+
+LAUNDRY SOAP.
+
+The most popular household soap is laundry soap. A tremendous amount of
+this soap is consumed each day in this country, and it is by far
+manufactured in larger quantities than any other soap. It is also a soap
+which must be sold cheaper than any other soap that enters the home.
+
+The consumers of laundry soap have been educated to use a full boiled
+settled rosin soap and to make a good article at a price this method
+should be carried out, as it is the one most advisable to use. The
+composition of the fats entering into the soap depends upon the market
+price of these, and it is not advisable to keep to one formula in the
+manufacture of laundry soap, but rather to adjust the various fatty
+ingredients to obtain the desired results with the cheapest material
+that can be purchased. It is impossible to use a good grade of fats and
+make a profit upon laundry soap at the price at which it must be
+retailed. The manufacturer of this grade of soap must look to the
+by-product, glycerine, for his profit and he is fortunate indeed if he
+realizes the entire benefit of this and still produces a superior piece
+of laundry soap.
+
+
+SEMI-BOILED LAUNDRY SOAPS.
+
+It is advantageous at times to make a laundry soap by a method other
+than the full boiled settled soap procedure as previously outlined. This
+is especially the condition in making a naphtha soap, in which is
+incorporated naphtha, which is very volatile and some of the well known
+manufacturers of this class of soap have adopted this process entirely.
+A laundry soap containing rosin cannot be advantageously made by the
+cold process, as the soap thus made grains during saponification and
+drops a portion of the lye and filling materials. By making a
+semi-boiled soap this objection is overcome. The half boiled process
+differs from the cold process by uniting the fats and alkalis at a
+higher temperature.
+
+To carry out this process the following formulae have been found by
+experience to give satisfactory results.
+
+                     I.         lbs.
+
+    Tallow                       100
+    Rosin                         60
+    Soda Lye, 36deg. B.              80
+
+                    II.
+
+    Tallow                       100
+    Rosin                         60
+    Silicate of Soda              25
+    Soda Lye, 36deg. B.              85
+
+                    III.
+
+    Tallow                       100
+    Rosin                        100
+    Lye, 36deg. B.                  105
+    Silicate of Soda              25
+    Sal Soda Solution             20
+
+In any of these formulas the sodium silicate (40deg. B.) may be increased
+to the same proportion as the fats used. By so doing, however, twenty
+pounds of 36deg. B. lye must be added for every hundred pounds of silicate
+additional to that indicated or in other words, for every pound of
+silicate added 20 per cent. by weight of 36deg. B. lye must be put into the
+mixture. The rosin may also be replaced by a previously made rosin soap.
+
+To make a semi-boiled soap, using any of the above formulae, first melt
+the rosin with all or part of the fat, as rosin when melted alone
+readily decomposes. When the mixture is at 150deg. F. run it into the
+crutcher and add the lye. Turn on sufficient dry steam to keep the
+temperature of the soap at about 150deg. F. in the winter or 130deg. F. in
+summer. After the mass has been mixed for half an hour, by continuously
+crutching the soap it will at first thicken, then grain and it may again
+become thick before it becomes smooth. When the mass is perfectly smooth
+and homogeneous drop into a frame and crutch in the frame by hand to
+prevent streaking. After standing the required length of time the soap
+is finished into cakes as usual.
+
+
+SETTLED ROSIN SOAP.
+
+Settled rosin soaps are made from tallow, grease, cottonseed oil,
+bleached palm oils of the lower grades, corn oil, soya bean oil, arachis
+oil, distilled garbage grease, cottonseed foots or fatty acids together
+with an addition of rosin, varying from 24 per cent. to 60 per cent. of
+the fatty acids which should titer from 28 to 35. A titer lower than 28
+will prevent the finished kettle of soap from being capable of later
+taking up the filling materials. As has already been stated under
+hardened oils, these being very much higher in titer allow a greater
+percentage of rosin to be added. Thus hardened fish oils and cottonseed
+oil are gradually being more extensively employed in soaps of this
+character.
+
+The procedure of handling the kettle is similar to that given under full
+boiled soap. The stock is steamed out into a settling tank and allowed
+to settle over night, after which it is pumped into the soap kettle.
+Having stocked the kettle, open steam is turned on and 10deg.-12deg. B.
+lye is run in, while using a steam pressure of ninety to one hundred
+pounds in order to prevent too great a quantity of condensation of the
+steam, the water thus being formed weakening the lye. If a steam
+pressure of fifty to sixty pounds is available, a stronger lye (20deg.
+B.) should be added. Care must be taken not to allow the lye to flow in
+too rapidly or the soap will not grain. The saponification is only
+attained by prolonged boiling with sufficient lye of proper strength.
+When saponification has taken place, the mass begins to clear and a
+sample taken out with a paddle and cooled should show a slight pink with
+a 1 per cent. alcoholic phenolphthalein solution.
+
+It may be stated here that in using this indicator or any other to test
+the alkalinity of soap, the soap should always be cooled and firm, as
+whenever water is present, the dissociation of the soap thereby will
+always react alkaline. When this state is reached the mass is ready for
+graining, which is accomplished by distributing salt brine or pickle or
+spreading dry salt over the surface of the soap. The kettle is then
+thoroughly boiled until the mass shows a soft curd and the lye drops
+clearly from a sample taken out with a trowel or paddle. The steam is
+then shut off and the soap allowed to settle over night. The lyes are
+then run off to the spent lye tank for glycerine recovery. In
+saponifying a freshly stocked kettle it is apt to bunch. To prevent this
+salt is added at various times to approximately one per cent. of the fat
+used.
+
+If, by any possibility the soap has bunched, this condition may be
+remedied by the addition of more strong lye and boiling until it is
+taken up. To work a kettle to its full capacity it is advisable to make
+two "killing" changes. First add about 75 per cent. of the fat and grain
+as directed. Run off the spent lyes and then add the remainder of the
+stock and repeat the process. When the spent lye has been run to
+storage, the open steam is again turned on and 18deg. B. lye gradually
+allowed to run in. The rosin is now broken up and put into the kettle,
+or a previously made rosin soap is pumped in.
+
+Lye is then added until the soap has a sharp taste after about three
+hours of continuous boiling, or when the soap is in the closed state.
+More lye should then be run into the kettle to grain the soap well, the
+grain not being too small. Then allow the soap to settle over night and
+draw off the strengthening lye. The next day again boil up the kettle
+and add water until the soap thins out and rises or swells high in the
+kettle. A sample taken out at this stage upon a hot trowel should run
+off in large flakes. The surface of the soap should be bright and shiny.
+
+If the sample clings to the trowel, a slight addition of lye will remedy
+this defect. The kettle is then allowed to rest, to drop the nigre and
+to cool for some time, depending upon the size of the kettle. The proper
+temperature is such that after having been pumped to the crutcher and
+the filling materials having been added, a thermometer placed into the
+mass should indicate 128deg.-135deg. F. after the crutcher has run from
+ten to fifteen minutes. The filling material may consist of from 7-9 per
+cent. of sal soda solution, 36deg.-37deg. B. warm or just enough to
+close up the soap and make it rise high in the center of a screw
+crutcher and make it cling close to a warm trowel. Other fillers such as
+outlined below are added at this point.
+
+An addition of from 2-3 per cent. of a special mineral oil for this
+purpose will impart a finish to the soap and 3-5 per cent. starch added
+prevents the soap from cracking in the frames. Other filling material as
+silicate of soda, borax, talc or silex are used. After the filling
+material has been thoroughly crutched through the soap it is framed,
+and, after being several days in the frame to solidify and cool the soap
+is ready for slabbing, pressing and wrapping.
+
+In order to more definitely illustrate the composition of the mixture of
+fats and oils entering into the formation of a laundry soap a typical
+formula may be given for such a soap containing 40 per cent. rosin added
+to the amount of fats used:
+
+                                  lbs.
+    Grease                      7,000
+    Tallow                      4,000
+    Corn Oil                    7,000
+    Cottonseed Oil              3,000
+    Rosin                       8,400
+
+The following have been found to be satisfactory filling materials and
+are calculated upon the basis of a 1,400-pound frame of soap.
+
+                          I.             lbs.
+
+    Sodium Silicate, 38deg.-40deg. B.          100
+    Mineral Oil                           25
+    Sal Soda Solution, 36deg. B.             80
+    Borax                                  1
+
+                         II.
+
+    Sal Soda Solution, 36deg. B.             80
+    Mineral Oil                           25
+    Sodium Silicate                       60
+
+                        III.
+    Soda Ash                              10
+    Sal Soda                              55
+    Sodium Silicate                      115
+    Mineral Oil                           40
+    Brine (Saturated Solution)            10
+    Sodium Silicate, 38deg.-40deg. B.          100
+
+                         IV.
+    Sodium Silicate                      100
+    Silex or Talc                        200
+    Soda Ash                              50
+
+                         V.
+
+    Sal Soda Solution, 36deg. B.             90
+    Sodium Silicate                    50-60
+    Mineral Oil                           25
+    Borax Solution, 25deg. B. (hot)          15
+
+
+CHIP SOAP.
+
+Chip soap is used extensively in laundries but is also used largely in
+other branches. It may be made either as a settled soap or by the cold
+made process.
+
+To make a full boiled settled chip soap, proceed as directed under
+settled laundry soap. The kettle is stocked with light grease or a
+mixture of grease with corn oil or other cheap oils. For this kind of
+soap the rosin is eliminated.
+
+Chip soap may be filled as well as laundry soap. This is done in the
+crutcher and the following adulterations are suitable.
+
+                                   lbs.
+    Settled Soap                   700
+    Soda Ash                        35
+    Sodium Silicate                215
+                     or
+    Settled Soap                   700
+    Silicate of Soda               560
+    Soda Ash                        18
+    Carbonate of Potash, 26deg. B.     50
+
+The cheapest method of drying is by running this soap through a drying
+machine and this is the procedure usually carried out for making dried
+chip soap.
+
+
+COLD MADE CHIP SOAPS.
+
+To make chip soaps by the cold process a sweet tallow of low percentage
+of free fatty acid should be employed. The tallow is heated to 120deg. to
+135deg. F. and the lye run in slowly at first and then the silicate of soda
+is added. The mass is then mixed until a finger drawn through the soap
+leaves a slight impression, then dropped into frames or barrels. Soaps
+containing a small percentage of fat should be well covered in the frame
+for twenty-four hours to retain their heat and insure proper
+saponification. The following formulae are suitable:
+
+                        I.                lbs.
+    Tallow                               1,200
+    Soda Lye, 35deg. B.                       850
+    Sodium Silicate                        750
+
+                      II.
+    Tallow                                 475
+    Ceylon Cocoanut Oil                    100
+    Soda Lye, 37deg. B.                       325
+    Potash Lye, 37deg. B.                      56
+
+                      III.
+    Tallow                                 500
+    Soda Lye, 37-1/2deg. B.                   297
+    Sodium Silicate                        416
+    Potash Lye, 37-1/2deg. B.                  37-1/2
+
+                       IV.
+    Tallow                                 450
+    Soda Lye, 37-1/2deg. B.                   255
+    Sodium Silicate                        450
+    Potash Lye, 37-1/2deg. B.                  50
+
+                       V.
+    Tallow                                 450
+    Soda Lye, 35deg. B.                       470
+    Sodium Silicate                        650
+
+                      VI.
+    Tallow                                 420
+    Sodium Silicate                        600
+    Soda Lye, 37-12deg. B.                    270
+
+
+UNFILLED CHIP SOAP.
+
+A very good grade of chip soap is made by employing no filling material
+whatsoever, but unfortunately the price of this soap has been cut to
+such an extent that these can not compete with a filled chip. A number
+of the best soaps of this kind are made from a settled soap using a
+light grease with corn oil. A soap of this nature is made as follows.
+
+                                          lbs.
+    Settled Soap                           800
+    Sal Soda Solution, 36deg.-37deg. B.          252
+    Soda Ash                               182
+
+If this soap is run into frames it may be stripped and chipped in two
+days.
+
+
+SOAP POWDERS.
+
+Soap powders have become so great a convenience as a general cleansing
+agent that to eliminate them from the household necessities would mean
+much unnecessary energy and work to the great number of consumers of
+this product. They may be manufactured so cheaply and still be
+efficient, that their use has almost become universal for cleansing and
+scouring purposes. The uses to which soap and scouring powders are
+adapted are too well known to enter into a description of their
+employment. Since they offer a greater profit to the manufacturer than
+ordinary household soap, many brands are extensively advertised.
+
+Numerous combinations for soap powders might be cited and it is a simple
+matter to vary the ingredients as to fat content and manufacture a
+powder of this sort as low as a cent a pound. Many substances are
+incorporated with soap, such as salt, soda ash, tripoli, crushed
+volcanic deposits, ground feldspar, infusorial earth of various kinds,
+silex, etc. In addition to these various fillers, compounds with true
+cleansing and bleaching properties, in addition to soap, are added, such
+as the salts of ammonium (sal ammoniac, carbonate of ammonia), sodium
+perborate and the peroxides of various metals. The public, however, have
+been accustomed to receive a large package of soap or scouring powder
+for a small amount of money and it is a difficult matter for the
+manufacturer to add more expensive substances of this nature to his
+product, to increase its efficiency, without raising the price or
+decreasing the size of the package.
+
+In manufacturing soap powders, the dried soap chips might be mixed with
+the filler and alkali and then pulverized. This method is not
+extensively employed nevertheless. The process which is the most
+economical is one whereby the ingredients are mixed in a specially
+adapted mixer for heavy material until dry and then run directly to the
+crusher and pulverizer, after which it is automatically packed, sealed
+and boxed. Another method of procedure is to run out the mixture from
+the crutcher to the frames, which are stripped before the soap cools,
+and is cut up at once, for if it hardens it could not be cut with wires.
+It is better, however, to run the mixture into sheets upon a specially
+constructed floor and break up the mass when cool.
+
+Formulae for soap powders which have been found to be suitable for
+running dry in the mixer follow:
+
+                        I
+    Soda ash, 58 per cent.                   42 lbs.
+    Silica                                  220  "
+    Settled soap (usually cottonseed).       25  "
+    Salt                                     10  "
+
+                       II
+    Soap (settled cottonseed)                40 lbs.
+    Soda ash, 58 per cent.                   60  "
+
+                      III
+    Settled soap                            100 lbs.
+    Soda ash, 58 per cent.                  400  "
+
+Fillers in varying proportions may replace the soda ash in the above
+formulae. It is of course understood that the soap has been previously
+made and run as molten soap into the crutcher.
+
+The following soap powders will not dry up in the crutcher upon running,
+but are of the class which may be framed or run on the floor to
+solidify:
+
+
+                         I
+    Soap                                 850 lbs.
+    Filler                               400  "
+    Sal soda solution, 20 degs. B        170  "
+
+                       II
+    Soap                                 650 lbs.
+    Filler                               550  "
+    Sal soda solution, 20 degs. B.       340  "
+
+                      III
+    Soap                                  80 lbs.
+    Filler                               550  "
+    Sal soda solution                    170  "
+
+                      IV
+    Soap (settled tallow)                800 lbs.
+    Filler                               400  "
+    Sal soda solution                    170  "
+    Water                                100  "
+
+                       V
+
+First saponify 100 parts house grease and 100 parts ordinary grease and
+make a run soap. Then use in crutcher either:
+
+    Soap                                 400 lbs.
+    Filler                               575  "
+    Hot water                             60  "
+                         or
+    Soap                                 200 lbs.
+    Hot water                            200  "
+    Filler                               625  "
+
+It would be a simple matter to write numerous additional formulae, but
+the above are typical. The manufacturer must judge for himself just what
+filling material to use. The filler indicated in the above formulae is
+therefore left open. A few formulae for more expensive powders than
+those given recently appeared among others in the "Seifensieder
+Zeitung"[9]:
+
+
+                     I
+
+    Powdered soap                         90 lbs.
+    Sodium perborate                      10  "
+
+The perborate should be added when the powder is perfectly dry or it
+loses its bleaching properties.
+
+                     II
+
+    Soap powder, 20 per cent. fat.
+    Cocoanut oil fatty acids              25 lbs.
+    Olein                                 25  "
+    Bone fat                              70  "
+    Soda lye, 30 degs. B.                 90  "
+    Water                                150  "
+    Ammonium carbonate                   125  "
+
+                     III
+
+    Soap powder, 10 per cent. fat.
+    Cocoanut oil fatty acids              20 lbs.
+    Olein                                 10  "
+    Bone fat                              20  "
+    Soda lye, 30 degs. B.                 30  "
+    Water                                175  "
+    Ammonium carbonate                   175  "
+
+
+LIGHT OR FLUFFY POWDERS.
+
+Light or fluffy powders containing 35-45% moisture can be made in two
+ways. The first method requiring a minimum equipment is to mix the
+powder and sal soda in a mixer, allow it to stand in frames for a week
+to crystallize or spread it on the floor for a few hours to dry and then
+grinding it.
+
+The continuous method finishes the powder in a few minutes and with a
+minimum amount of labor. By this process the various ingredients, soap,
+soda ash solution, etc., are measured, run by gravity into the mixer,
+mixed and the molten mass run over the crystallizer or chilling rolls
+thru which either cold water or brine is pumped. From the roll the
+powder is scraped off clean by a knife, passes to a screen which sends
+the tailings to a grinder, falls into a storage bin from whence it is
+weighed and packed by an automatic weighing machine into cartons made up
+in most cases by another machine. Due to the large percentage of
+moisture contained in these soap powders the carton is generally wrapped
+in wax paper to aid in the prevention of the escape of moisture.
+
+
+SCOURING POWDERS.
+
+Scouring powders are very similar to soap powders and differ only in the
+filler used. We have already considered these fillers under scouring
+soap, from which they do not differ materially. They are usually
+insoluble in water to aid in scouring. The mixer used for substances of
+this kind in incorporating the soap and alkali must be of strong
+construction.
+
+
+SCOURING SOAP.
+
+Scouring soaps resemble soap powders very closely in their composition,
+in that they are a combination of soap and filling material. Since more
+lather is required from a scouring soap than in soap powders, a cocoanut
+oil soap is generally used. The usual filling material used is silex.
+The greatest difficulty in the manufacture of scouring soap is the
+cracking of the finished cake. This is usually due to the incorporation
+of too great an amount of filler, or too high a percentage of moisture.
+
+In manufacturing these soaps the cocoanut oil is saponified in the
+crutcher with 38 degs. B. lye, or previously saponified as a run soap,
+as already described under "Marine Soaps." To twenty-five parts of soap
+are added a percentage of 38 degs. B. sal soda or soda ash solution,
+together with a small quantity of salt brine. To this mixture in the
+crutcher seventy-five parts of silex are then added, and a sufficient
+amount of hot water to make the mass flow readily. Care must be
+exercised to not add too great a quantity of water or the mass will
+crack when it cools. The mass is then framed and cut before it sets, or
+poured into molds and allowed to set. While silex is the most
+extensively used filler for scouring soaps, it is feasible to
+incorporate other substances of like character, although it is to be
+remembered that the consumer is accustomed to a white cake, such as
+silex produces. Any other material used to replace silex should also be
+as fine as this product.
+
+
+FLOATING SOAP.
+
+Floating soap occupies a position midway between laundry and toilet
+soap. Since it is not highly perfumed and a large piece of soap may be
+purchased for small cost, as is the case with laundry soap, it is
+readily adaptable to general household use. Floating soap differs from
+ordinary soap in having air crutched into it which causes the soap to
+float in water. This is often advantageous, especially as a bath soap,
+and undoubtedly the largest selling brand of soap on the American market
+today is a floating soap.
+
+In the manufacture of floating soap a high proportion of cocoanut oil is
+necessary. A most suitable composition is one part cocoanut oil to one
+part of tallow. This is an expensive stock for the highest grade of soap
+and is usually cheapened by the use of cottonseed or various other
+liquid oils. Thus it is possible to obtain a floating soap from a kettle
+stocked with 30 per cent. cocoanut oil, 15 per cent. cottonseed oil and
+55 per cent. tallow. With this quality of soap, however, there is a
+possibility of sweating and rancidity, and of the soap being too soft
+and being poor in color.
+
+The process of manufacture is to boil the soap in an ordinary soap
+kettle, after which air is worked into the hot soap by a specially
+constructed crutcher, after which the soap is framed, slabbed, cut into
+cakes and pressed.
+
+Concerning the boiling of the soap, the saponification must be carefully
+carried out, as the high proportion of cocoanut oil may cause a violent
+reaction in the kettle causing it to boil over.
+
+The method of procedure is the same as for a settled soap up to the
+finishing. When the mass is finally settled after the finish, the soap
+should be more on the "open" side, and the object should be to get as
+long a piece of goods as possible.
+
+Due to its high melting point, a much harder crust forms on the surface
+of a floating soap and in a greater proportion than on a settled soap
+during the settling. In a large kettle, in fact, it has been found
+impossible to break through this crust by the ordinary procedure to
+admit the skimmer pipe. Much of the success of the subsequent operations
+depends upon the completeness of the settling, and in order to overcome
+the difficulties occasioned by the formation of the crust everything
+possible should be done in the way of covering the kettle completely to
+enable this period of settling to continue as long as possible.
+
+When the soap is finished it is run into a specially constructed U-shape
+crutcher, a Strunz crutcher is best adapted to this purpose, although a
+rapidly revolving upright screw crutcher has been found to give
+satisfaction upon a smaller scale, and a sufficient quantity of air
+beaten into the soap to make it light enough to float. Care must be
+taken not to run the crutcher too rapidly or the soap will be entirely
+too fobby. During this operation the mass of soap increases in bulk,
+and after it has been established how much air must be put into the soap
+to satisfy the requirements, this increase in bulk is a criterion to
+estimate when this process is completed.
+
+It is of course understood that the longer the crutching continues the
+greater quantity of air is incorporated and the increase of volume must
+be established for a particular composition by sampling, cooling the
+sample rapidly and seeing if it floats in water. If the beating is
+continued too long an interval of time, the finished soap is too spongy
+and useless.
+
+The temperature of the mass during crutching is most important. This
+must never exceed 158 degrees F. At 159 degrees F. the operation is not
+very successful, yet the thermometer may indicate 140 degrees F. without
+interfering with this operation. If, however, the temperature drops too
+low, trouble is liable to be met with, by the soap solidifying too
+quickly in the frames.
+
+When the crutching is completed, the soap is allowed to drop into frames
+through the valve at the bottom of the crutcher and rapidly crutched by
+the hand in the frames to prevent large air spaces and then allowed to
+cool. It is an improvement to jolt the frames as they are drawn away as
+this tends to make the larger air bubbles float to the surface and thus
+reduce the quantity of waste. When the soap has cooled, the frame is
+stripped and the soap slabbed as usual. At this point a layer of
+considerable depth of spongy soap will be found to have formed. This of
+course must be cut away and returned to the kettle. The last few slabs
+are also often rejected, inasmuch as the weight of the soap above them
+has forced out so much of the air that the soap no longer floats. As a
+fair average it may be estimated that not more than 50 to 60 per cent.
+of the soap in the kettle will come out as finished cakes. the
+remaining 40 to 50 per cent. being constituted by the heavy crust in the
+kettle, the spongy tops, the bottom slabs and scrapings. This soap is of
+course reboiled and consequently not lost, but the actual cakes obtained
+are produced at a cost of practically double labor.
+
+It is advisable to add a small quantity of soap blue color to the mass
+while crutching to neutralize the yellowish tint a floating soap is
+liable to have.
+
+Some manufacturers add a percentage of carbonate of soda, about 3 per
+cent., to prevent the soap from shrinking. Floating soap may also be
+loaded with sodium silicate to the extent of about 5 per cent.
+
+
+TOILET SOAP.
+
+It is not a simple matter to differentiate between toilet soaps and
+various other soaps, because numerous soaps are adaptable to toilet
+purposes. While some soaps of this variety are manufactured by the cold
+made or semi-boiled process, and not milled, the consumer has become
+accustomed to a milled soap for general toilet use.
+
+The toilet base most extensively employed is a tallow and cocoanut base
+made as a full boiled settled soap. The manufacture of this base has
+already been outlined and really needs no further comment except that it
+is to be remembered that a suitable toilet soap should contain no great
+excess of free alkali which is injurious to the skin. Cochin cocoanut
+oil is preferable to the Ceylon cocoanut oil or palm kernel oil, to use
+in conjunction with the tallow, which should be a good grade and color
+if a white piece of goods is desired. The percentage of cocoanut oil may
+be anywhere from 10 to 25 per cent., depending upon the kind of lather
+required, it being remembered that cocoanut oil increases the lathering
+power of the soap.
+
+In addition to a tallow base, numerous other oils are used in the
+manufacture of toilet soaps, especially palm oil, palm kernel oil, olive
+oil and olive oil foots, and to a much less extent arachis or peanut
+oil, sesame oil and poppy seed oil, oils of the class of cottonseed,
+corn and soya bean oils are not adapted to manufacturing a milled soap,
+as they form yellow spots in a finished cake of soap which has been kept
+a short time.
+
+Palm oil, especially the Lagos oil, is much used in making a palm base.
+As has already been stated, the oil is bleached before saponification. A
+palm base has a yellowish color, a sweetish odor, and a small quantity
+added to a tallow base naturally aids the perfume. It is especially good
+for a violet soap. The peculiarity of a palm oil base is that this oil
+makes a short soap. By the addition of some tallow or twenty to
+twenty-five per cent. of cocoanut oil, or both, this objection is
+overcome. It is a good plan in using a straight palm base to add a
+proportion of yellow color to hold the yellowish tint of this soap, as a
+soap made from this oil continues bleaching upon exposure to air and
+light.
+
+Olive oil and olive oil foots are used most extensively in the
+manufacture of castile soaps. The peculiarity of an olive oil soap is
+that it makes a very slimy lather, and like palm oil gives the soap a
+characteristic odor. An olive oil soap is usually considered to be a
+very neutral soap and may readily be superfatted. Much olive oil soap is
+used in bars or slabs as an unmilled soap and it is often made by the
+cold process. Peanut oil or sesame and poppy seed oil often replaces
+olive oil, as they form a similar soap to olive oil.
+
+In the manufacture of a toilet soap it is hardly practical to lay down a
+definite plan for the various bases to be made. From the combination of
+tallow, palm oil, cocoanut oil, palm kernel oil, olive oil and olive oil
+foots, a great many bases of different proportions might be given. The
+simplest method is to make a tallow base, a palm base and an olive oil
+base. Then from these it is an easy matter to weigh out any proportion
+of these soap bases and obtain the proper mixture in the mill. If,
+however, as is often the case, a large quantity of soap base of certain
+proportions of these, four or even more of these fats and oils is
+required, it is not only more economical to stock the kettle with the
+correct proportion of these oils, but a more thorough mixture is thus
+obtained by saponifying these in the kettle. In view of the fact that it
+is really a question for the manufacturer to decide for himself what
+combination of oils he desires for a particular soap we will simply
+outline a few typical toilet soap bases in their simplest combination.
+It is understood that these soaps are suitable for milled soaps and are
+to be made as fully boiled settled soaps. Palm kernel oil may be
+substituted for cocoanut oil in all cases.
+
+
+TALLOW BASE.
+
+    Tallow                       75-90 parts
+    Cocoanut oil                 25-10 parts
+
+
+PALM BASE.
+
+    Bleached Lagos palm oil      75-80 parts
+    Cocoanut oil                 25-20 parts
+
+                or
+
+    Tallow                          30 parts
+    Palm oil                        60 parts
+    Cocoanut oil                    10 parts
+
+
+OLIVE OIL BASE (WHITE).
+
+    Olive oil                    75-90 parts
+    Cocoanut oil                 25-10 parts
+
+                  or
+
+    Olive oil                    40 parts
+    Tallow                       40 parts
+    Cocoanut                     20 parts
+
+Where a green olive oil base is desired, olive oil foots are substituted
+for the olive oil. Peanut oil may replace the olive oil or part of it,
+the same being true of sesame oil and poppy seed oil.
+
+
+PALM AND OLIVE BASE.
+
+    Palm oil                     50 parts
+    Olive oil                    30 parts
+    Cocoanut oil                 20 parts
+
+                  or
+
+    Palm oil                     20 parts
+    Olive oil                    10 parts
+    Tallow                       50 parts
+    Cocoanut oil                 20 parts
+
+
+CHEAPER TOILET SOAPS.
+
+It is often necessary to manufacture a cheaper grade of soap for toilet
+purposes to meet the demand of a certain class of trade as well as for
+export. To accomplish this it is of course necessary to produce a very
+inferior product and run down the percentage of fatty acids contained in
+the soaps by the addition of fillers or to use cheaper oils in
+manufacturing. The most simple method of filling a soap is to load it at
+the mill with some substance much less expensive than the soap itself.
+Many of the cheaper toilet soaps, however, are not milled and it is,
+therefore, necessary to follow out some other procedure.
+
+Milled soaps, as has just been stated, are loaded at the mill. The
+consumers of cheaper toilet soaps in this country are accustomed to a
+milled soap and this grade of soap for home consumption is very often
+filled with numerous substances, but most generally by adding starch
+and talc. The addition of such materials of course later exhibit
+themselves by imparting to the cake of soap a dead appearance. Talc is
+more readily detected in the soap than starch by washing with it, as
+talc is insoluble and imparts a roughness to the soap, like sand or
+pumice, as the soap wears down. It may readily be added to 20 per cent.
+by weight. Starch is to be preferred to talc, in loading a soap, as it
+is not so readily noticeable in washing. It leaves the cake itself
+absolutely smooth although the lather formed is more shiny. This
+substance may be employed to as high a percentage as one-third the
+weight of the soap. It is, of course, possible to cheapen the best soap
+base by this method and the price may be further lowered by using the
+less expensive oils and fats to make the soap base.
+
+
+RUN AND GLUED UP SOAPS.
+
+A very cheap grade of soap may be made by making a run soap and adding
+the filler e. g. sodium silicate in the kettle during saponification.
+The percentage of fatty acids may be brought down to 10 per cent.,
+although of course a soap of this type shrinks a whole lot upon
+exposure.
+
+In making a "glued up" soap the procedure is the same for making the
+soap itself as with a settled soap, except that the soap is finished
+"curd" and later filled in the crutcher. The percentage of fatty acids
+in a soap of this type is seldom below 50 per cent.
+
+The method of "gluing up" a soap is best illustrated by a typical soap
+of this character in which the kettle is charged with the following
+stock.
+
+    Bleached palm oil                          5 parts
+    Distilled grease                           2   "
+    Cotton oil foots stock, 63% fatty acid     1   "
+    Rosin                                      4   "
+
+The palm oil is first run into the kettle, saponified and washed to
+extract any glycerine, then the rest of the fats and finally the rosin.
+The soap is then finished and settled as with a boiled settled soap. To
+assure success it is absolutely necessary that the soap settle as long a
+period as possible, or until the temperature is about 150 degs. F. The
+ideal temperature for carrying out the "gluing up" process is 140 degs.
+F., as at a lower temperature than this the soap is liable to cool too
+quickly and not be thoroughly glued up. A higher temperature than 150
+degs. F. causes delay in that the soap does not properly take the filler
+at a higher temperature and the soap must be kept in the crutcher until
+the temperature drops to the right point.
+
+The soap is run into the crutcher and the percentage of fatty acids run
+down to 50-55 per cent. with one of the following mixtures:
+
+    Sodium silicate, 59-1/2deg. B.     1 part
+    Potassium carbonate, 51deg. B.     1  "
+
+                    or
+
+    Sodium silicate, 59-1/2deg. B.     1 part
+    Potassium carbonate, 51deg. B.     1  "
+    Sodium sulfate, 28deg. B.          1  "
+
+From 230 to 300 pounds of either of these mixtures are required for a
+crutcher holding 2,600 pounds of soap.
+
+The crutching is continued until the mass is well "spiked," that is to
+say, a freshly broken surface of the soap, as the crutcher blade is
+jerked away, stands up like shattered sheets in triangular form
+[Transcriber's note: three triangles]), which retain their shape
+perfectly. When this condition is realized the soap is run into frames
+which are carefully crutched by hand to remove any air spaces. The
+surface of the soap is then smoothed down and heaped up in the center.
+After standing a day to contract, the surface is again leveled and a
+snugly-fitting board placed on the top of the soap upon which a weight
+is placed or upon which the workman treads and stamps until the surface
+is flat, thus assuring the further removal of air spaces. The soap
+remains in the frame from six to eight days and is then slabbed, barred
+and pressed by the usual method employed for soaps thus handled without
+milling.
+
+In a soap of this nature no hard and fast rule can be laid down as to
+the quantity of solution to be used for "gluing up" or the strength of
+the solution. In a soap of the type described the most satisfactory
+appearing cake will be obtained from a soap containing 58 per cent.
+fatty acids. That is to say, about 8 per cent. to 10 per cent. filling
+solution is added per hundred pounds of soap. The filling solutions
+given are very satisfactory. Carbonate of soda should be avoided in
+connection with sodium silicate as the property of efflorescing on the
+surface of the finished cake after a short time will prove detrimental.
+To assure successful gluing up it is advisable to experiment upon a
+small scale to determine the exact extent to which the filling solution
+should be diluted. Various proportions of water are added to a certain
+quantity of the filled soap. After the soap has been filled in a small
+receptacle a sample is taken and rubbed between the fingers. If the
+freshly exposed surface is smooth and glossy, the filling solution is
+weak enough, if rough it is too strong. It is of course understood that
+the temperature must be correct, 140 degs. to 150 degs. F., or the soap
+will be rough. By this means the operator can readily judge the correct
+strength of his filling solution. When properly carried out a perfectly
+satisfactory soap is obtained.
+
+
+CURD SOAP.
+
+The object of a soap which is finished "curd" or grained, is to obtain a
+harder piece of goods from low titer fat or to increase the percentage
+of fatty acids in the finished soap. This is still another method of
+producing a cheap grade of soap as by its adoption the cheaper oils and
+fats may be used to obtain a firm piece of soap.
+
+A typical charge for curd soap is:
+
+    Red oil        63 parts
+    Tallow         10  "
+    Rosin          27  "
+
+Cotton seed foots may be employed in place of red oil and a tallow of
+too high titer is not suitable for this kind of soap.
+
+The red oil and tallow are first saponified with 15 degs. B. lye, boiler
+pressure 80-90 pounds, 18 degs. B. lye for lower steam pressure, and two
+washings given to extract the glycerine. The rosin is added at the
+strengthening change and at the finish the soap is "pitched," that is to
+say, the soap is settled over night only. The next day the lyes are
+drawn off and a portion of the nigre pumped to another kettle which
+prevents later streaking of the soap. The soap is then boiled with 18
+degs. B. lye as with another strengthening change under closed steam.
+Salt brine or "pickle," 15 degs. B. is then added and the mass boiled
+with closed steam until the brine reaches a density of 18 degs. B. and
+the kettle pumped the next day. A soap of this type requires either hand
+or power crutching to assure homogeneity and prevention of streaks. To
+obviate any air spaces it is advisable to place over the top of the
+frame a tightly-fitted board which is heavily weighted down. This soap
+is also pressed without any milling.
+
+
+COLD MADE TOILET SOAPS.
+
+Comparatively little toilet soap is made by the cold or semi-boiled
+processes. While these are the simplest methods of manufacturing soaps
+the drawbacks of using them are numerous and only in a few cases are
+they very extensively employed. To make a toilet soap by the cold
+process a combination of good grade tallow and cocoanut oil is required.
+It requires 50 per cent. by weight of 36 degs. B. lye to saponify a
+given weight of tallow and 50 per cent. of 38 degs. B. lye for cocoanut
+oil. The lyes are used full strength or may be reduced slightly with
+water and the method of procedure is the same as already given in the
+general directions for cold made soaps.
+
+Cold made soaps are readily filled with sodium silicate which is added
+at the same time the stock is put into the crutcher. In adding the
+silicate it is necessary to add additional lye to that required for
+saponifying the fats, about 20 per cent. of 36 degs. B. lye is the
+proper amount. There is of course a certain amount of shrinking due to
+the addition of this filler and the finished cake is exceedingly hard,
+yet the author has seen a good looking cake of cheap soap made from as
+high a proportion as 420 parts of tallow to 600 parts of silicate.
+
+Cold made soaps are usually pressed without milling, although it is
+readily feasible to mill a cold made soap provided it is not a filled
+soap such as has just been described.
+
+
+PERFUMING AND COLORING TOILET SOAPS.
+
+Equally important as the soap itself or even to a greater extent is the
+perfume of a toilet soap. A prominent manufacturer recently made the
+statement, which is often the truth, that it makes no difference to the
+public what kind of soap you give them, as long as you put plenty of
+odor into it. The perfuming of soaps is an art in itself and a subject
+to be treated by one versed in this particular branch. We can only take
+into account the importance of the perfume as related to toilet soap
+not only, but the necessity of adding a certain proportion of the
+cheaper products of odoriferous nature to laundry soap to cover and
+disguise the odor of even this type of soap.
+
+The price of a cake of toilet soap to a great extent depends upon the
+perfume, and the manufacturer should aim to give the best possible
+perfume for a certain price. He should not allow his personal likes or
+dislikes to enter into the judgment of whether an odor is good or not,
+but submit it to a number of persons to obtain the concensus of opinion.
+In giving or selling a piece of soap to the consumer, it is second
+nature for him to smell it, and in the great majority of cases his
+opinion is formed not from any quality the soap itself may have during
+use, but from the odor. This only emphasizes the fact that the perfume
+must be pleasing, not to one person, but to the majority, and many
+brands owe their popularity to nothing more than the enticing perfume.
+
+Perfuming of soap is closely allied to the soap making industry, but as
+stated a branch in itself. It is, therefore, not our purpose to give
+numerous formulae of how to perfume a soap, but rather to advise to go
+for information to some one who thoroughly understands the
+characteristics of the numerous essential oils and synthetics and give
+positive information for the particular odor desired. Under no
+circumstances is it advisable to purchase a perfume already compounded,
+but since all perfumes are a blend of several or many essential oils and
+synthetics, it is a more positive assurance of obtaining what is
+desired, by purchasing the straight oils and blending or mixing them as
+one desires.
+
+The perfume is added to a milled soap just before the milling process in
+the proper proportion per hundred pounds of soap. In cold made or
+unmilled soaps it is added in the crutcher while the soap is still hot.
+By this method, of course, a proportion of the perfume is lost due to
+its being more or less volatile.
+
+
+COLORING SOAP.
+
+While much toilet soap is white or natural in color, many soaps are also
+artificially colored. The soap colors used for this purpose are mostly
+aniline dyestuffs. The price of these dyestuffs is no criterion as to
+their quality, as the price is usually regulated by the addition of some
+inert, water soluble substance like common salt or sugar.
+
+The main properties that a dyestuff suitable for producing a colored
+soap should have are fastness to light and to alkali. They should
+further be of such a type that the color does not come off and stain a
+wash cloth or the hands when the soap is used and should be soluble in
+water. Under no circumstances is it advisable to add these in such a
+quantity that the lather produced in the soap is colored. It is
+customary to first dissolve the dye in hot water as a standardized
+solution. This can then be measured out in a graduate and added to the
+soap the same time as the perfume is put in. About one part of color to
+fifty parts of water is the proper proportion to obtain a perfect
+solution, though this is by no means fixed. In making up a solution thus
+it is an improvement to add to the same about one-half of one per cent.
+of an alkali either as the hydroxide or carbonate. Then, if there is any
+possibility of change of color due to alkalinity of the soap, it will
+exhibit itself before the color is added.
+
+A particularly difficult shade to obtain is a purple, as there is up to
+the present time no purplish aniline color known which is fast to light.
+Very good results in soap may be obtained by mixing a fast blue, as
+ultramarine or cobalt blue, with a red as rhodamine or eosine.
+
+Inasmuch as the colors for soap have been carefully tested by most of
+the dyestuff manufacturers, and their information, usually reliable, is
+open to any one desiring to know about a color for soap, it is better to
+depend upon their experience with colors after having satisfied one's
+self that a color is what it is represented for a particular shade, than
+to experiment with the numerous colors one's self.
+
+
+MEDICINAL SOAPS.
+
+Soap is often used for the conveyance of various medicants, antiseptics
+or other material presumably beneficial for treatment of skin diseases.
+While soap is an ideal medium for the carrying of such materials, it is
+an unfortunate condition that when incorporated with the soap, all but a
+very few of the numerous substances thus employed lose their medicinal
+properties and effectiveness for curing skin disorders, as well as any
+antiseptic value the substance may have. Soap is of such a nature
+chemically that many of the substances used for skin troubles are either
+entirely decomposed or altered to such an extent so as to impair their
+therapeutic value. Thus many of the claims made for various medicated
+soaps fall flat, and really have no more antiseptic or therapeutic merit
+than ordinary soap which in itself has certain germicidal and cleaning
+value.
+
+In medicating a soap the material used for this purpose is usually added
+at the mill. A tallow and cocoanut oil base is best adapted for a soap
+of this type. The public have been educated more or less to the use of
+colored soap to accentuate its medicinal value, and green is undoubtedly
+the most popular shade. This inference, however, is by no means true for
+all soaps of this character. Possibly the best method of arranging
+these soaps is briefly to outline some medicinal soaps.
+
+
+SULPHUR SOAPS.
+
+The best known sulphur soaps contain anywhere from one to 20 per cent.
+of flowers of sulphur. Other soaps contain either organic or inorganic
+sulphur compounds.
+
+
+TAR SOAP.
+
+The tar used in the manufacturing of tar soap is obtained by the
+destructive distillation of wood, the pine tar being the most
+extensively employed. While the different wood tars contain numerous
+aromatic compounds, such as phenols, phenyl oxides, terpenes and organic
+acids, these are present in such a slight proportion so as to render
+their effectiveness practically useless. It has, therefore, been tried
+to use these various compounds contained in the tar themselves to make
+tar soap really effective, yet tar is so cheap a substance that it is
+usually the substance used for medicating a tar soap. About 10 per cent.
+of tar is usually added to the soap with 2 ounces of lamp black per
+hundred pounds of soap.
+
+
+SOAPS CONTAINING PHENOLS.
+
+Phenol (Carbolic Acid) is most extensively used in soaps of this kind,
+which are called carbolic soaps. Carbolic soaps are generally colored
+green and contain from 1 to 5 per cent. phenol crystals.
+
+The cresols are also extensively used for making soaps named carbolic.
+These substances impart more odor to the soap and really have more
+disinfecting powers than phenol when incorporated with soap.
+
+Other soaps, containing the phenol group, which are well known are
+resorcinol soap, salol soap, thymol soap, naphthol soap, etc. From one
+to five per cent of the compound after which the soap is named is
+usually incorporated with the soap.
+
+
+PEROXIDE SOAP.
+
+Hydrogen peroxide in itself is an excellent disinfectant. It loses all
+its medicinal value, however, when added to the soap. To overcome this
+objection various metallic peroxides are added to the soap, as sodium
+peroxide, zinc peroxide and barium peroxide. These generate hydrogen
+peroxide by the addition of water. Sodium perborate is also used in
+peroxide soaps, as this substance is decomposed by water into hydrogen
+peroxide and sodium metaborate.
+
+
+MERCURY SOAPS.
+
+Mercuric chloride (corrosive sublimate) is most extensively used for the
+production of mercury soaps. Because of its extremely poisonous
+properties care should be taken in using it. Since it really eventually
+loses any antiseptic value in the soap through forming an insoluble
+mercury soap it might better be omitted entirely.
+
+
+LESS IMPORTANT MEDICINAL SOAPS.
+
+While the above mentioned soaps are probably the best known medicated
+soaps, there are numerous other soaps which may be classed under these
+kinds of soaps. Thus we have cold cream soap, which can be made by
+adding Russian Mineral Oil, 1 to 5 per cent., to the soap; witch hazel
+soap, made by the addition of extract of witch hazel; iodine soap, made
+by adding iodine or iodoform; formaldehyde soap, made by adding
+formaldehyde; tannin soaps, made by adding tannin. In fact, there have
+been incorporated in soap so great a number of substances that the list
+might be greatly enlarged.
+
+Medicated soaps are not only used in solid form, but in powder, paste
+and liquid soap as well. The only difference in a soap like those just
+referred to is that the medicant is incorporated with these forms of
+soaps as convenience directs.
+
+
+CASTILE SOAP.
+
+A pure castile soap should be made from olive oil. This, however, is not
+always the case, as a number of oils as well as tallow are used to
+adulterate this oil to cheapen it, and there are even some soaps called
+castile which contain no olive oil at all. Most of the pure castile soap
+used in this country is imported, as it is a difficult matter for the
+American manufacturer to compete with the pure imported castile soap,
+since both labor and oil itself are so much cheaper in the vicinities of
+Europe where this oil is produced, that this advantage is more than
+compensated by the carrying and custom charges by importing the castile
+soap.
+
+Castile soap may be made either by the full boiled or cold process.
+There are numerous grades of olive oil, and those used for soap making
+are denatured to lower the duty charges. Olive oil makes a hard white
+soap, usually sold in bars, and olive oil foots a green soap, due to the
+coloring matter contained in this oil.
+
+To make a boiled castile soap, a composition of 10 per cent. Cochin
+cocoanut oil and 90 per cent. olive oil may be used. To cheapen this,
+peanut oil (Arachis oil) may entirely replace the olive oil, or about 20
+per cent. of corn or soya bean oil may be added. The oils are saponified
+as usual in making a settled soap and to prevent rancidity the soap is
+boiled near the finish for some time in the closed state with
+sufficient excess of alkali to give it a sharp taste, then grained with
+lye, the lye drawn off, closed with water and then grained with salt.
+This process is repeated until the desired strength is reached. The last
+graining should not be too great, and on the last change the soap should
+not be thinned out, as it will contain too great a quantity of water
+when slabbed.
+
+In making a cold castile soap the usual method is pursued as already
+directed under cold made soap. When the soap is taken from the crutcher
+it is advisable, however, to keep the soap in the frame well covered to
+assure complete saponification. Some manufacturers use very small frames
+which are placed into compartments, well insulated to retain heat.
+Several formulae for cold made castile soaps, follow. It may be noted
+that some of these contain practically no olive oil.
+
+                 I
+
+    Olive oil                        2030
+    Palm kernel                       674
+    Soda lye, 35 per cent. B.        1506
+
+                 II
+
+    Olive oil                        2030
+    Cochin cocoanut oil               674
+    Soda lye, 36 per cent. B.        1523
+    Sodium Silicate                    82
+
+                 III
+
+    Palm kernel oil                  1578
+    Tallow                            940
+    Olive oil                           7
+    Sodium silicate, 20 per cent.     190
+    Soda lye, 36 per cent. B.        1507
+
+                 IV
+
+    Olive oil (yellow)               1000
+    Soda lye, 37 per cent. B.         500
+
+                 V
+
+    Olive oil                          90
+                   or
+    Palm kernel            }           10
+    Cochin or cocoanut oil }           10
+    Lye, 37 per cent. B.               51
+
+If any of the soaps containing a high proportion of cocoanut oil are
+boiled the soap will float. It is therefore necessary to keep the
+temperature as low as possible.
+
+
+ESCHWEGER SOAP (BLUE MOTTLED).
+
+Eschweger soap is a colored mottled or marbled soap made to a very
+slight extent in this country. Inasmuch as it has been introduced to the
+export trade, it is made for this purpose by some manufacturers. A high
+percentage of cocoanut oil is usually used together with tallow and
+grease. About one-third of each is a typical formula. In a soap of this
+character the fact that cocoanut oil soap takes up a large quantity of
+water and salts of various kinds and is difficult to salt out is made
+use of. The tallow and grease are first saponified as usual, then the
+cocoanut oil is pumped and saponified. When the saponification is nearly
+completed either silicate or carbonate of soda or common salt are added
+to make the soap "short" so as to form the mottle. The finishing of a
+soap of this type can only be gained by practice and it is rather
+difficult to explain the exact appearance of the kettle at this stage.
+The surface of the soap should be bright and lustrous with the steam
+escaping in numerous places in rose-like formation. A sample on the
+trowel should have a slight sharpness to the tongue and be plastic. When
+the soap slides from the trowel it should break short. When the soap has
+reached this stage the desired coloring matter, usually ultramarine, is
+added to the soap either in the kettle or crutcher and the soap framed.
+The yield is 200-215 pounds per hundred pounds of stock.
+
+Several modifications of this general method for Eschweger soap are used
+by adopting the half boiled or cold process.
+
+
+TRANSPARENT SOAP.
+
+Transparent soap is really not a most desirable soap for toilet
+purposes, as it contains an excess of free alkali. It has, nevertheless,
+met with public approval because of the fact it is novel in being
+transparent. Except for this fact very little merit can be claimed for a
+soap of this kind.
+
+The transparency of soap is generally due to the presence of alcohol,
+sugar or glycerine in the soap when it is made. It is very essential in
+a soap of this character, where lightness and clearness of color are
+desired, that the material for making the soap be carefully selected as
+to color and purity. The perfumes also play an important part in the
+color of the soap and many of the tinctures, balsams and infusions used
+in perfuming soap may eventually cause trouble by spotting. If the soap
+is artificially colored, which is almost always the case, the dyestuffs
+used for this purpose should have careful attention and only those
+should be used which are known to resist the action of alkalis. Where
+rosin is used this product must be of the better grade. Distilled water
+is always preferable for use in transparent soap. The government permits
+the use of a specially denatured alcohol. This alcohol is not taxed and
+consists of grain (ethyl) alcohol denatured with 5 per cent. wood
+(methyl) alcohol. Some soapmakers prefer to use a more expensive refined
+methyl alcohol, but outside of adding to the cost of the soap, there is
+no particular advantage. The glycerine should be chemically pure. As to
+the oils and fats these should be low in acid and of good color. Under
+no circumstances should the crutcher or kettle in which the soap is made
+be rusty or unclean in any way. For a light soap enameled utensils are
+to be preferred.
+
+To obtain transparency in soap the following general methods may be
+given.
+
+1. Where the transparency is due to sugar.
+
+2. Where alcohol and glycerine produce transparency.
+
+3. Where (1) or (2) is supplemented by the use of castor oil.
+
+4. Where transparency depends upon the percentage of fatty acid in a
+soap and the number of times the soap is milled.
+
+Under the first method at least 25 per cent. of the charge should be
+cocoanut oil, the other constituent being tallow or any fat or oil
+capable of giving a sufficiently hard soap. The soap is boiled and
+finished as usual, then run to the crutcher to be mixed with a strong
+cane sugar solution, containing 10-20 per cent. sugar of the weight of
+the soap. The sugar is dissolved in its own weight of water and the
+solution heated to 175 degs. F. before being very slowly added to the
+soap. As the water evaporates, soaps of this type show spots due to the
+sugar thus being thrown out of solution.
+
+Transparent soap made under the second method may be saponified as usual
+and consist of any good toilet base. The soap is run to the crutcher and
+mixed with 95 per cent. alcohol in the proportion of one part alcohol to
+two parts of fatty acid contained in the soap together with glycerine in
+the same proportion.
+
+By the third method castor oil alone may be used to make the soap or
+added to any of the above bases up to 33-1/3 per cent. of the charge. If
+castor oil only is used, but 2 per cent. or 3 per cent. of sugar is
+required.
+
+In the last method a combination of 80 per cent. tallow, very low in
+free acid, 20 per cent. cocoanut oil and 5 per cent. W. W. rosin is a
+suitable charge. The saponification and finishing is carried out as with
+a full boiled soap. The soap is then placed into a jacketed vessel,
+provided with dry-steam coils, by which the excess water is evaporated
+from the soap until it contains 73 per cent. fatty acids. When the thick
+mass reaches this stage it is framed and when cool is suitable for
+obtaining a semi transparency which now depends upon the number of times
+the soap is milled, it being, of course, inferred that no solid matter
+of any sort be added to the soap.
+
+
+COLD MADE TRANSPARENT SOAP.
+
+While transparent soaps may be made by the above general methods they
+are usually made by the semi-boiled or cold process. By this process a
+more satisfactory soap is obtained and it is more simple to carry out. A
+detailed description of this method is best and most easily given by
+using a typical formula.
+
+    Charge:
+
+      Tallow                       193-1/2 lbs.
+      Cochin Cocoanut Oil          169-1/2 "
+      Castor Oil                    89-1/2 "
+      Soda Ash                       7-3/4 "
+      Soda Lye, 36 degs. B.        256     "
+      Sugar (Cane)                 198     "
+      Alcohol                      126     "
+      Water (Distilled)             80     "
+
+To proceed, first place into a crutcher or jacketed kettle the oils and
+fat and heat to 140 degs. F. Then add the soda ash dissolved in about 30
+pounds of the water, after which the lye is added and the mass stirred
+until a finger or stick run over the surface leaves an imprint. Where
+the soap has reached this stage, it is well covered and allowed to stand
+about two hours or until it bulges in the center, after which the rest
+of the water which should contain no lime or other mineral substance and
+which is preferably distilled water, is added. The sugar is then slowly
+shoveled in while the mass is stirring and finally the alcohol is poured
+in. The heat is then increased to 160 degs. F. by dry steam and the soap
+crutched until dissolved. Under no circumstances should any soap be
+allowed to remain above the surface of the mass on the sides of the
+mixer. This crutching operation consumes about one hour, and when
+finished the soap should stand in the vessel about half an hour when a
+small sample is taken out to cool. This sample should be clear and show
+an excess of alkali. If it is not clear more alcohol is added, if not of
+sufficient strength more lye put in until the desired condition is
+reached. The perfume and color are now added.
+
+The soap is then framed and allowed to set after which it is cut,
+allowed to dry slightly and then pressed. To obtain a polished cake
+transparent soaps are often planed before pressing and after pressing
+polished with a soft cloth, dampened with alcohol. Instead of framing
+this soap, it is sometimes "tubed," that is to say, the soap from the
+crutcher is run into specially constructed tubes of a shape near that of
+the desired cake and allowed to cool, after which it is cut and pressed.
+All scraps are returned to the crutcher, but in so doing the soap is
+slightly darkened in color. It is advisable to expose a finished cake of
+transparent soap to the air for some time as by so doing it becomes
+clearer.
+
+Other formulae for cold made transparent soaps made as just outlined
+follow:
+
+                      I.
+    Bleached Tallow                134 lbs.
+    Cochin Cocoanut Oil             88  "
+    Castor Oil                      20  "
+    W. W. Rosin                      7  "
+    Cane Sugar                      64  "
+    Water                           32  "
+    Glycerine                       34  "
+    Soda Lye, 38 degs. B.          135  "
+    Alcohol                         16 gal.
+
+                     II.
+    Tallow                         211   lbs.
+    Cochin Cocoanut Oil            185     "
+    Castor Oil                      97-1/2 "
+    Soda Ash                         8-1/2 "
+    Water                          106     "
+    Soda Lye, 38 degs. B.          279     "
+    Sugar                          216     "
+    Alcohol                        137     "
+
+                     III.
+    Castor Oil                      60    lbs.
+    Cochin Cocoanut Oil            195     "
+    Tallow                         120     "
+    Alcohol                        115     "
+    Sugar                           90     "
+    Water                           53     "
+    Glycerine                       53     "
+    Soda Lye, 38 degs. B.          205-1/2 "
+
+                     IV.
+    Tallow                         100 lbs.
+    Cochin Cocoanut Oil            100  "
+    Castor Oil                      60  "
+    Glycerine                       20  "
+    Rosin, W. W.                    20  "
+    Sugar                           40  "
+    Water                           50  "
+    Soda Lye, 36 degs. B.          164  "
+    Alcohol                          8 gal.
+
+                      V.
+    Tallow                         174 lbs.
+    Cocoanut Oil                   114  "
+    Soda Lye, 38 degs. B.          170  "
+    Sugar                           80  "
+    Water                           72  "
+    Alcohol                         16 gal.
+
+Rosin may be added in this formula up to 20 per cent. of fats used and
+the tallow cut down correspondingly.
+
+
+SHAVING SOAPS.
+
+The requirements of a shaving soap are somewhat different than those of
+other soaps. To be a good shaving soap the lather produced therefrom
+must be heavy, creamy, but not gummy, and remain moist when formed on
+the face. The soap itself should be of a soft consistency so as to
+readily adhere to the face when used in stick form. It should
+furthermore be neutral or nearly so to prevent the alkali from smarting
+during shaving.
+
+Shaving soap is made in the form of a stick, and a tablet for use in the
+shaving mug. Some shavers prefer to have the soap as a powder or cream,
+which are claimed to be more convenient methods of shaving. While a
+liquid shaving soap is not as well known because it has not yet become
+popular, some soap for shaving is made in this form.
+
+Formerly shaving soap was extensively made from a charge of about 80
+parts tallow and 20 parts cocoanut oil as a boiled settled soap, but
+either making the strengthening change with potash lye or using potash
+lye in saponifying the stock and graining with salt. Soaps for shaving
+made in this manner are very unsatisfactory, as they do not produce a
+sufficiently thick or lasting lather and discolor very materially upon
+ageing. Potassium stearate forms an ideal lather for shaving, but
+readily hardens and hence needs some of the softer oils, or glycerine
+incorporated with it to form a satisfactory soap for shaving.
+
+The selection of materials for making a shaving soap is important. The
+tallow used should be white and of high titer. Cochin cocoanut oil is to
+be preferred to the other kinds, and the alkalis should be the best for
+technical use that can be purchased--76 per cent. caustic soda and 88-92
+per cent. caustic potash are suitable. By the use of stearic acid it is
+a simple matter to reach the neutral point which can be carefully
+approximated.
+
+The following are shaving soap formulae which have been found to give
+good satisfaction:
+
+                      I.       lbs.
+    Tallow                         360
+    Stearic acid                    40
+    Soda lye, 41deg. B.               147
+    Potash lye, 34deg. B.              87
+    Water                           32
+    Gum tragacanth                   1
+
+                     II.       lbs.
+    Tallow                         282
+    Cocoanut oil                    60
+    Stearic acid                    50
+    Bayberry wax                    18
+    Soda lye, 41deg. B.               147
+    Potash lye, 34deg. B.              90
+    Water                           32
+
+                     III.      lbs.
+    Tallow                         400
+    Cocoanut oil                   176
+    Stearic acid                   415
+    Caustic soda, 40deg. B.           182
+    Caustic potash, 38deg. B.         108
+
+To proceed, first run into the crutcher the tallow, cocoanut oil and
+bayberry wax when used, and bring the temperature of the mass up to
+140deg.-160deg. F. by dry steam. Then add the caustic soda lye and keep on
+heat with occasional mixing until it is all taken up. When this stage is
+reached gradually add all but about 5 per cent. of the potash lye, and
+complete the saponification. This point having been reached, the heat is
+turned off; the crutcher is run and the stearic acid, previously melted
+by dry steam in a lead-lined or enameled vessel, is run in in a
+continuous stream and the crutching continued for fifteen minutes to
+half an hour. Samples are taken at this time, cooled and tested by
+alcoholic phenolphthalein solution. If too alkaline more stearic acid is
+added, if too acid more potash lye from that previously reserved. After
+each addition of lye or stearic acid the mass is crutched from 10 to 15
+minutes longer, another sample is taken, cooled and again tested. When
+the phenolphthalein shows a very light pink after several minutes, the
+soap is practically neutral, although at this point one can better judge
+by dissolving a sample in hot neutralized alcohol made by putting into
+the alcohol a few drops of phenolphthalein, and then adding weak alkali
+drop by drop from a burette until a slight pink, not yellow, tint is
+obtained, and noting the color of the solution. The solution should show
+a very light pink when the soap is properly neutralized. When this stage
+is arrived at the gum tragacanth, previously softened in water, is
+crutched in if it is to be added. The soap is then framed, stripped in
+three or four days, dried and milled.
+
+The formulae as given are for shaving sticks, and do not readily press
+unless thoroughly dried. A more satisfactory result is obtained by
+adding at the mill 25 per cent. of white tallow base to obtain a
+satisfactory mug soap.
+
+
+SHAVING POWDER.
+
+Shaving powder differs from the soaps just described in being
+pulverized, usually adding up to 5 per cent. starch to prevent caking.
+Any of the above soaps, dried bone dry, with or without the addition of
+tallow base make a satisfactory powder for shaving.
+
+
+SHAVING CREAM.
+
+Shaving cream is now a very popular shaving medium due to the rapidity
+and convenience with which one can shave by the use of this product.
+Formerly shaving cream was made from the liquid oils like olive oil and
+a soft fat like lard, together with cocoanut oil. Now, however, most of
+the popular shaving creams are made from stearic acid and cocoanut oil,
+as a far superior product is obtained by the use of these substances. By
+using these a more satisfactory cream is obtained, and it is far more
+convenient to make. The lather also produced therefrom is more suitable
+for shaving, being thick, creamy and remaining moist.
+
+A few typical formulae for shaving creams of this type are as follows:
+
+                          I.       lbs.
+    Cochin cocoanut oil             26
+    Stearic acid                   165
+    Caustic potash lye, 50deg. B.      69
+    Glycerine C. P.                 76
+    Water                           38
+
+                          II.      lbs.
+    Cochin cocoanut oil             18
+    Stearic acid                    73
+    Caustic potash lye, 39deg. B.      54
+    Glycerine                       33
+    Water                           27
+
+                         III.      lbs.
+    Cochin cocoanut oil             18
+    Stearic acid                    73
+    Caustic potash lye, 39deg. B.      54
+    Glycerine                       20
+    Water                           40
+
+                         and       lbs.
+
+    Stearic acid                    60
+    Glycerine C. P.                 85
+    Water                          165
+    Sodium carbonate                50
+    Borax                            1
+
+To make a shaving cream by Formula I or II, the cocoanut oil and
+glycerine are first put into a suitable mixing apparatus or crutcher,
+and heated to 120deg. F. A part or all the potash lye is then added and the
+cocoanut oil saponified. The rest of the potash lye and the water are
+then added, and with the mixer running the stearic acid, previously
+melted in a lead-lined or enameled vessel, is then poured in in a stream
+and the mass stirred until smooth, care being exercised not to aerate it
+too much. The cream is then tested for alkalinity, the best method being
+by that described under shaving soap, in which the sample is dissolved
+in alcohol. Because of the large quantity of water present,
+phenolphthalein is unsatisfactory, as dissociation of the soap may show
+a pink indication in spite of the fact the mass is on the acid side. For
+a quick method of testing the bite on the tongue is a satisfactory
+criterion. If a cooled sample bites the tongue more stearic acid is
+added until there is a 3% excess of this. When the proper neutralization
+has taken place the cream is perfumed and framed in a special frame, or
+it may be allowed to cool in the mixer and perfumed the next day. When
+cool the cream is strained, or put through an ointment mill, after which
+it is ready to fill into tubes.
+
+The procedure for the first part of Formula III is the same as that just
+given. The second part of the formula is made the same as a vanishing
+cream for toilet purposes. To make this, first melt the stearic acid as
+already directed. Dissolve the sodium carbonate and borax in water and
+when dissolved add the glycerine and stir. Then heat this solution to
+about 100deg.-120deg. F. and while stirring in a suitable mixing machine
+into which this solution has been poured after being heated, or better
+still in which it has been heated by dry steam, add the stearic acid.
+Continue mixing until smooth and then allow to cool, or run into frames
+to cool.
+
+When the shaving cream and vanishing cream are both cool, they are mixed
+in the proportion of one of the former to two of the latter. It is
+claimed that in thus making a shaving cream a smoother product is
+obtained, although it may be said that the vanishing cream is merely a
+soft soap and the ultimate result is the same as though the various
+ingredients were added in one operation, rather than making two separate
+products and then mixing them, thereby considerably increasing the cost
+of manufacture.
+
+
+PUMICE OR SAND SOAPS.
+
+Pumice and sand are at times added to soap to aid in the removal of dirt
+in cleansing the hands. In some cases these soaps are made in the form
+of a cake, in others they are sold in cans in the form of a paste.
+
+A hand paste is usually made by merely dissolving ordinary tallow base
+in two or three times its weight of hot water and mixing in the desired
+quantity of pumice or sand and in some instances adding a little
+glycerine to keep it soft or a solvent of some kind for grease. It may
+also be made by directly incorporating any of these in a potash soap.
+
+A cold made or semi-boiled cocoanut or palm kernel oil soap is the base
+used to add the pumice or sand to in making a cake soap of this sort.
+The following formulae serve as a guide for these soaps.
+
+                       I.
+
+    Palm Kernel or Ceylon Cocoanut Oil      705 lbs.
+    Pumice (Powdered)                       281 "
+    Soda Lye, 38deg. B.                        378 "
+
+                      II.
+
+    Cocoanut Oil                            100 "
+    Soda Lye, 38deg. B.                         55 "
+    Water                                     6 "
+    Silver Sand (fine)                       60 "
+
+To proceed place the oil in a crutcher and heat to 140deg. F. Sift in the
+pumice and mix thoroughly. The lye is then added which causes a curdling
+of the grain. The stirring is continued until the grain closes and the
+soap is smooth, after which the desired perfume is added and the soap
+dropped into a frame and crutched by hand. When the soap is set, it is
+slabbed, cut into cakes, dried slightly and pressed.
+
+
+LIQUID SOAPS.
+
+Liquid soaps are merely solutions of a potash soap, usually cocoanut oil
+soap, although corn oil is used to make a cheap soap. One of the
+difficulties encountered in liquid soap is to keep it clear. At a low
+temperature a sediment is often formed, but this can be overcome by the
+use of sugar and filtering the soap through a filter press at a low
+temperature. In order to prevent the soap from freezing, it is necessary
+to lower the freezing point by the addition of glycerine or alcohol.
+
+To make liquid soap by any of the formulae given below, the oil is first
+run into a jacketed kettle with a stirring device, and heated to about
+120deg. F. The potash lye is then added and the oil saponified. When the
+saponification takes place, especially when cocoanut oil is used, the
+mass swells rapidly and may foam over the sides of the kettle unless
+water is used to check this, or a kettle of about four to five times the
+capacity of the total charge of soap is used. When the saponification
+has occurred, the sugar, borax and glycerine are added, the water run in
+and the mixture stirred until the soap is thoroughly dissolved. Heat
+aids materially in dissolving the soap. The soap is then allowed to cool
+and if color or perfume is to be added this is stirred in, after which
+the soap is cooled and filtered or else run directly into barrels.
+
+Tallow is not suitable for making a clear liquid soap since it is too
+high in stearine which when formed into the stearate makes an opaque
+solution. The formulae herewith given have been found to give good
+practical results.
+
+                   I.               lbs.
+    Cocoanut oil                    130
+    Caustic potash lye, 28deg. B.      135
+    Sugar                            72
+    Borax                             2
+    Water                           267
+
+                  II.               lbs.
+    Corn oil                        130
+    Caustic potash lye, 26deg. B.      135
+    Sugar                            72
+    Borax                             2
+    Water                           267
+
+                  III.              lbs.
+    Cocoanut oil                    100
+    Caustic potash lye, 28deg. B.      102
+    Glycerine                       100
+    Sugar                            70
+    Water                           833
+
+Formulae I and II contain about 20 per cent. fatty acids. It is
+possible, of course, to either increase or decrease the percentage of
+fatty acid by varying the amount of water. The water used in making
+liquid soaps, of course, should be soft, for hard water forms insoluble
+soaps which precipitate and cause a sediment.
+
+
+USE OF HARDENED OILS IN TOILET SOAPS.
+
+While the introduction of the hydrogenation of oils is a decided advance
+in the production of suitable cheaper oils for soap making,
+comparatively little hardened oil is employed for soap making in America
+up to the present time. In Europe, however, considerable advance has
+been made by the use of such oils for manufacturing soap therefrom and a
+number of plants turn out large quantities of hydrogenated oils for soap
+making as well as for edible purposes. Recently a company has been
+formed in this country for hardening oils and it is very probable that
+the future will see this material extensively used in our own country,
+as these appear to be the one present hope of the soap manufacturer as a
+check on the ever increasing cost of fats and oils now used in making
+soap.
+
+It is an unfortunate condition that hydrogenated oils produced abroad
+are sold under names which give absolutely no indication as to the oil
+which has been hardened. The softer and cheaper oils like fish oil,
+linseed oil, cottonseed oil, etc., are generally hardened for soap
+manufacture to different degrees of hardness. While it is impossible to
+definitely state just what products as Candelite, Talgol, Krutolin or
+several other coined names of hardened oils are, various investigators
+have experimented with them as to their adaptability for producing
+toilet soaps and found that suitable toilet soaps may be made from them.
+While many objections were at first met with concerning soaps made from
+these products, as to their unsatisfactory saponification, the poor
+lathering quality of the soaps and their odor and consequent difficulty
+in perfuming, the results of most investigators along these lines
+indicate that these in many cases were due to prejudice against or
+unfamiliarity with handling oils of this type for soap making.
+
+In manufacturing soap from hardened oils it is usually necessary to
+incorporate with the charge lard, tallow, tallow oil or some other soft
+oil of this nature. Satisfactory bases for toilet soaps, made as boiled
+settled soap by the use of Talgol (undoubtedly hardened fish oil), are
+said to be made by the formulae[10] below.
+
+              I.
+
+    Tallow                  45 parts
+    Talgol                  40 "
+    Cocoanut Oil            15 "
+
+              II.
+
+    Cocoanut Oil (Ceylon)    6 "
+    Tallow                  12 "
+    Talgol, Extra           12 "
+
+The method of boiling a soap of this type does not differ materially
+from that of making settled tallow soap base. The soap itself has a
+different odor than a straight tallow base, but is said to make a very
+satisfactory soap for milling and to be of good appearance.
+
+Satisfactory transparent soaps are made from the hardened oil Candelite,
+which replaces the tallow in transparent soap formulae such as have
+already been given in the section under "Transparent Soaps." The method
+of manufacturing a soap by the use of this product varies in no way from
+the usual method employed for making these soaps.
+
+Since hydrogenated oils are high in stearine, their use in shaving soaps
+is a decided advantage. It has previously been pointed out that
+potassium stearate forms an ideal lather for shaving, and in the
+hydrogenating process the olein is converted to stearine. Thus a
+hardened oil is advantageous in a shaving soap. As an example of a cold
+made soap for shaving the following may be taken.[11]
+
+    Talgol Extra            50 lbs.
+    Cocoanut Oil            10 "
+    Lard                    10 "
+    Soda Lye, 38deg. B.        20 "
+    Potash Lye, 37deg. B.      21 "
+
+This soap may be made in a crutcher by the method generally used in
+making soap by the cold process.
+
+
+TEXTILE SOAPS.
+
+Soap is a very important product to every branch of the textile
+industry. For woolen fabrics it is used for scouring, fulling and
+throwing the wool; in the silk industry it is necessary for degumming
+the raw silk, as well as for dyeing; in the cotton mills it is used to
+finish cotton cloth and to some extent in bleaching; it is, furthermore,
+employed in a number of ways in the manufacture of linen. Large
+quantities of soap are thus consumed in an industry of so great an
+extent and the requirements necessitate different soaps for the
+different operations. We will, therefore, consider these in detail.
+
+
+SCOURING AND FULLING SOAPS FOR WOOL.
+
+The soaps used to scour wool and for fulling the woven cloth are usually
+made as cheaply as possible. They are, however, generally pure soaps, as
+filling material such as sodium silicate does not readily rinse out of
+the wool and if used at all must be added very sparingly. Both cold made
+and boiled settled soaps are made for this purpose. The soap is
+generally sold in barrels, hence is run directly to these from the
+crutcher or soap kettle. As cold made soaps the following serve for wool
+scouring or fulling.
+
+                 I.
+
+    Palm Oil                         200 lbs.
+    Bone Grease                      460 "
+    Soda Lye, 36deg. B.                 357 "
+    Water                            113 "
+    Soda Ash                          50 "
+    Citronella                         2 "
+
+                 II.
+
+    Palm Oil (Calabar, unbleached)   155 "
+    House Grease                     360 "
+    Soda Lye, 36deg. B.                 324 "
+    Water                            268 "
+    Sodium Silicate                   83 "
+
+                 III.
+
+    House Grease                     185 "
+    Palm Oil (unbleached)            309 "
+    Soda Lye, 36deg. B.                 309 "
+    Water                            391 "
+    Soda Ash                          70 "
+    Sodium Silicate                   60 "
+    Corn Starch                       10 "
+
+These soaps are made in a crutcher by the usual process for cold-made
+soaps, crutched until smooth, dropped into a barrel and crutched by hand
+the next day or just before cooling.
+
+As a settled soap for these operations the following charge is typical:
+
+    Palm Oil                                               34 parts
+    Cottonseed foots or its equivalent in fatty acids      33  "
+    Rosin                                                  10  "
+    House Grease                                           23  "
+
+The method of boiling such a soap is the same as for any settled soap up
+to the strengthening change. When this stage is reached, sufficient lye
+is added to strengthen the kettle strongly. It is then boiled down with
+closed steam on salt brine or "pickle" until a sample of the lye taken
+from the bottom stands at 16deg.-22deg. B. The soap is then run into
+barrels and after standing therein for a day is hand crutched until cool
+to prevent streaking of the soap.
+
+Besides a soap of this type a settled tallow chip soap is used.
+
+
+WOOL THROWER'S SOAP.
+
+Soaps for wool throwing are sometimes made from olive oil foots but
+these are often objected to because of the sulphur-like odor conveyed to
+the cloth due to the method by which this oil is extracted with carbon
+disulphide. A potash soap hardened somewhat with soda is also used. As a
+formula for a suitable soap of this type this may be given.
+
+    Olive Oil Foots              12   parts
+    Corn Oil                     46     "
+    House Grease                 20     "
+    Soda Lye, 36deg. B.              3     "
+    Potassium Carbonate (dry)     5-3/4 "
+    Potassium Hydrate (solid)    23     "
+
+This soap is made as a "run" soap by the general directions already
+given for a soap thus made. The kettle is boiled with open and closed
+steam, adding water very slowly and aiming to obtain a 220-225 per cent.
+yield or fatty acid content of the finished soap of 46 per cent. When
+the soap is finished a sample cooled on a plate of glass should be
+neither slippery or short, but should string slightly. The finished soap
+is run directly into barrels.
+
+A soap for wool throwing by the semi-boiled process may be made from
+olive oil foots in a crutcher thus:
+
+    Olive Oil Foots          600 lbs.
+    Potash Lye, 20deg. B.        660 "
+
+The oil is heated to 180deg. F., the lye added and the mass stirred until
+it bunches, when it is dropped into barrels.
+
+
+WORSTED FINISHING SOAPS.
+
+For the finishing of worsted cloth soaps high in cocoanut oil or palm
+kernel oil are preferred. These soaps are finished very neutral, being
+made as settled soaps, but given an extra wash change after
+strengthening strongly. They are then finished as usual and run into
+barrels. If framed too hot, the high percentage of cocoanut oil causes
+mottling, which is prevented by crutching by hand until the temperature
+of the soap is 140deg.-145deg. F. Some typical charges, all of which are
+saponified with soda lye, follow:
+
+                    I.
+
+    Palm Kernel Oil                      60 parts
+    Corn Oil                             40 "
+
+                    II.
+
+    Palm Kernel Oil                      30 "
+    Red Oil (single pressed)             70 "
+
+                    III.
+
+    Red Oil                              33-1/3 "
+    Corn Oil                             33-1/3 "
+    Cocoanut Oil or Palm Kernel Oil      33-1/3 "
+
+
+SOAPS USED IN THE SILK INDUSTRY.
+
+Soap is used to a very large extent in silk mills, both for degumming
+the raw silk and in silk dyeing. Raw silk consists of the true silk
+fibre known as fibroin and a gummy coating, sericin, which dulls the
+lustre of the silk unless removed. For this purpose a slightly alkaline
+olive oil foots soap is best adapted, although palm oil and peanut oil
+soaps are sometimes used, as well as soaps made from a combination of
+house grease to the extent of 30 per cent., together with red oil or
+straight olein soaps, both of which are artificially colored green. In
+using house grease, if 30 per cent. is exceeded in combination with red
+oil, the titer is raised to such an extent that the soap does not
+readily rinse from the silk nor dissolve readily. They are also not
+advisable because they impart a disagreeable odor to the silk.
+
+To make a soap for this purpose from olive oil foots it is made as a
+settled soap, care being taken to thoroughly boil the mass on the
+saponification change in the closed state to assure proper
+saponification. The kettle is usually grained with lye and given a good
+wash change to remove the excess strength. The change previous to the
+finish should not be too heavy or too large a nigre results. The lighter
+the grain is, the better the finished kettle is. A yield of 150 per
+cent. is usually obtained. This soap is generally run to a frame,
+slabbed upon cooling and packed directly into wooden cases.
+
+For silk dyeing the above soap is suitable, although any well-made soap
+of good odor and not rancid is useable. While soap alone is often used
+in the bath for silk dyeing, certain dyestuffs require the addition of
+acetic or sulphuric acid, which sets free the fatty acids. If these be
+of bad odor it is taken up by the silk and is difficult to remove. The
+most generally used soaps are the just mentioned olive foots soap or a
+soap made from a good grade red oil.
+
+Both kinds are extensively used.
+
+
+SOAPS USED FOR COTTON GOODS.
+
+In the manufacture of cotton goods, as compared to the wool and silk
+industries, very much less soap is used and it is only applied to the
+finished fabric either to clean the cloth preparatory to dyeing or to
+aid in dyeing with certain colors. It is also used in calico printing.
+For cleansing the cloth ordinary chip soap is suitable although a more
+alkaline soap finished as a curd soap is an advantage in that the free
+alkali contained therein aids in removing the dirt and has no harmful
+effect on the cotton. For dyeing cotton goods or to brighten certain
+colors after dyeing an olive oil foots soap is most generally employed.
+In calico printing soap is used to wash and clear the cloth after
+printing. A soap for this purpose should be easily soluble in water and
+contain no free alkali, rosin or filler. The best soaps for use in
+calico printing are either an olive oil foots soap or an olein soap.
+
+
+SULPHONATED OILS.
+
+While sulphonated oils are not used to any great extent in the
+manufacture of soap, they are used very largely in the dyeing and
+printing of turkey and alizarine reds on cotton as well as other colors.
+Just what action these oils have is not known. Turkey red oil or
+sulphonated castor oil is the best known sulphonated oil.
+
+The process of making these oils is simple. The equipment necessary is a
+wooden tank or barrel of suitable capacity, approximately two and a half
+times the amount of oil to be treated. There are furthermore required
+other tanks or vessels to hold the solutions used such as caustic soda,
+ammonia and acid. The tank to be used for the preparation of sulphonated
+oil should be provided with a valve at the bottom of the tank and a
+gauge to measure the quantity of liquid therein.
+
+The process is carried out as follows:
+
+Three hundred pounds of castor oil are placed in the tank and 80 pounds
+at 66 deg. B. sulphuric acid are weighed out in another vessel. The acid
+is run into the tank containing the oil in a very thin stream while the
+oil is well stirred. At no time should the temperature exceed 40 deg. C.
+This operation should consume at least an hour and stirring should be
+continued half an hour longer to insure the thorough mixing of the oil
+with the acid. The mass is then allowed to settle for 24 hours, after
+which 40 gallons of water are added and the mixture stirred until it has
+a uniform creamy color indicating no dark streaks. This mixing process
+should be carefully carried out and when completed allowed to settle 36
+hours. At this point the mass will have separated into two layers, the
+lower layer consisting of a water solution of acid and the upper layer
+of oil. The former is run out through the valve located at the bottom of
+the tank. Another wash may now be given or dispensed with as desired. In
+this wash the addition of salt or sodium sulphate at the rate of 1-1/2
+pounds per gallon of water is advisable. A 24 deg. B. caustic soda
+solution is prepared and added slowly to the acidified oil with constant
+stirring. The mass first turns creamy, then becomes streaked, increasing
+in streaks as the caustic solution is poured in, and finally becomes
+clear and transparent. Water is now added to bring the volume to 75
+gallons. The oil is now milky in appearance, but the addition of a
+little more soda solution restores the transparency.
+
+In some cases ammonia is used in addition to caustic soda in
+neutralizing the oil. Three-fourths of the amount of caustic soda
+required to complete the neutralization is first added and then the
+neutralization is completed with a one to one liquid ammonia and water
+solution.
+
+FOOTNOTES:
+
+[9] Seifensieder Ztg., 40, 47, 1266 (1913).
+
+[10] Seifensieder Ztg. (1913), p. 334 and 338.
+         "         "   (1912), p. 1229 and 1257.
+
+[11] Seifensieder Ztg. (1912), p. 954.
+
+
+
+
+CHAPTER V
+
+Glycerine Recovery.
+
+
+The recovery of glycerine is very closely allied with the soap-making
+industry, because glycerine is the very valuable by-product obtained in
+the saponification of oils and fats. No soap plant is, therefore, fully
+equipped unless it has some method whereby the glycerine is recovered
+and the importance of recovering this product cannot be too strongly
+emphasized.
+
+It has already been pointed out that neutral fats or the glycerides are
+a combination of fatty acid with glycerine. These are split apart in the
+process of saponification. While by the term _saponification_ as used in
+soap making it is inferred that this is the combination of caustic
+alkalis with the fatty acids to form soap, this term is by no means
+limited to this method of saponification, as there are various other
+methods of saponifying a fat. The chemical definition of saponification
+is the conversion of an ester, of which glycerides are merely a certain
+type, into an alcohol and an acid or a salt of this acid. Thus, if we
+use caustic alkali as our saponifying agent for a fat or oil, we obtain
+the sodium or potassium salt of the higher fatty acids or soap and the
+alcohol, glycerine. On the other hand, if we use a mineral acid as the
+saponifying agent, we obtain the fatty acids themselves in addition to
+glycerine. While the former is by far the most generally employed for
+making soap, other processes consist in saponifying the fats by some
+method other than caustic alkalis and then converting the fatty acids
+into soap by either neutralizing them with sodium or potassium carbonate
+or hydrate.
+
+It is important to again point out here that fats and oils develop free
+fatty acid of themselves and that the development of this acid
+represents a loss in glycerine. The selection of an oil or fat for soap
+making should therefore to a large extent be judged as to its
+adaptability by the free fatty acid content, as the higher this content
+is, the greater is the loss in the glycerine eventually obtained.
+Glycerine often represents the only profit to a soap manufacturer. It is
+indeed necessary to determine the percentage of free fatty acid before
+purchasing a lot of stock to be made into soap.
+
+In taking up the question of glycerine recovery we will consider the
+various methods thus:
+
+1. Where the glycerine is obtained from spent lye by saponifying the
+fats or oils with caustic alkali.
+
+2. Where the glycerine is obtained by saponifying the fats or oils by
+some other method than the above, of which there are the following:
+
+    (a) Twitchell process.
+    (b) Saponification by lime in autoclave.
+    (c) Saponification by acid.
+    (d) Saponification by water in autoclave.
+    (e) Fermentative (Enzymes).
+    (f) Krebitz process.
+
+
+RECOVERY OF GLYCERINE FROM SPENT LYE.
+
+The spent lye obtained from the glycerine changes in making soap varies
+greatly, the quality depending upon the stock saponified and the soap
+maker's care in handling the operation. No two lyes run exactly alike as
+to proportion of the various ingredients, although they are all similar
+in containing the same substances either in solution or suspension.
+Spent lye is a water solution of mainly glycerine, free alkali either as
+caustic alkali or carbonate and salt, including sodium sulfate, but
+furthermore contains some soap and albuminous matter either in solution
+or suspension. Upon standing in the storage tank the greater part of
+the soap usually separates when the lye cools. In order to assure the
+greatest economical yield of glycerine by saponifying a fat with caustic
+soda it is necessary to obtain a proportion of three parts of water to
+every part of fat made into soap. Test runs have shown that this is the
+proper proportion and that it is not economical to greatly exceed this
+amount, and if a much less proportion is used the full yield of
+glycerine is not obtained.
+
+The spent lyes contain varying amounts of glycerine, the first change
+being richest in glycerine content, and this being reduced in the
+subsequent changes. If the lyes always run high in glycerine it is an
+indication that it is not all being obtained. The usual percentage is
+from 0.5% to 5% or even more, although the average is somewhere around
+2% to 3%. The lye as it comes from the kettle should not contain any
+more than 0.5% to 0.6% of free alkali calculated as sodium carbonate,
+Na_{2}CO_{3}. If the proportion is higher than this, it shows that the
+saponification has been conducted with too high a proportion of alkali,
+a condition which should be corrected in the kettle room. An excess of
+free alkali does not interfere to any great extent with the successful
+recovery of the glycerine, but is a waste of both alkali and the acid
+used in neutralizing this. It is, therefore, more economical to run a
+strong lye over fresh stock and neutralize the alkali thus, rather than
+treating the lye for glycerine recovery.
+
+Before the spent lye can be run into the evaporator it is necessary to
+remove the albuminous impurities and soap and to neutralize the excess
+alkali to between exactly neutral and 0.02% alkalinity. The lye should
+never be fed into the evaporator in the acid condition.
+
+In order to treat the spent lyes for evaporation, they are first allowed
+to cool in the storage tank, after which any soap which may have
+separated is skimmed off and returned to the soap kettle. This lye is
+then pumped to the treatment tank, an ordinary tank equipped with some
+method of agitating the liquor, either by a mechanical stirrer, steam
+blower or compressed air, until it is about two feet from the top.
+
+After the lye has been skimmed off it is thoroughly agitated and a
+sample taken. The amount of lye in the tank is then calculated. Spent
+lye is about 1.09 times heavier than water, or weighs about 9 pounds to
+the gallon. While the sample is being tested for alkalinity it is
+advisable to add sulfate of alumina, which may be dissolving while the
+sample is being titrated. This substance should be added in the
+proportion of anywhere from 6 to 14 pounds per thousand pounds of lye,
+depending upon the amount of impurities contained therein. For a clean
+lye six pounds per thousand is sufficient, but for an impure lye a
+greater quantity is necessary. The sulfate of alumina used should be
+free from arsenic and sulfides and should contain a minimum amount of
+grit (silica), as grit reduces the life of the pump valves. This may be
+estimated with sufficient accuracy by rubbing the filtered-off portions,
+insoluble in water between the fingers and a plate of glass. The object
+of adding the sulfate of alumina is to transform the soap contained in
+the lye into the insoluble aluminum soaps, and at the same time to
+coagulate the albuminous impurities. It must be remembered that the
+sulfate of alumina is added only for the fresh lye put into the tank.
+Thus if there were 10,000 pounds of lye in the treating tank when the
+fresh lye was run in, and 50,000 pounds when the tank is filled, adding
+nine pounds of sulfate of alumina per thousand of lye, only 360 pounds
+would be added or enough for 40,000 pounds. Sulfate of alumina
+neutralizes one-third of its weight of caustic.
+
+To determine the alkali in the sample, 10 cubic centimeters are pipetted
+into a beaker, a little distilled water added, then 3 or 4 drops of
+phenolphthalein indicator. From a burette, quarter normal (N/4) sulfuric
+acid is added until the pink color is just discharged. When this point
+is reached 4 to 5 c. c. more of acid are added and the solution is
+boiled to expel the carbon dioxide. Should the solution turn pink, it is
+necessary to add more acid. After having boiled for 3 to 4 minutes, N/4
+caustic soda is added until the pink color just returns and the amount
+of caustic soda used is read on the burette. The difference between the
+number of cubic centimeters of N/4 sulfuric acid and N/4 caustic soda
+gives the amount of alkali in the sample. By using a 10 c. c. sample and
+N/4 sulfuric acid and N/4 caustic soda each c. c. obtained by the
+difference of these two solutions is equal to one-tenth of one per cent.
+(0.1%) of the total alkali in the lye. As an example, say we first used
+7.7 c. c. of N/4 sulfuric acid to just discharge the pink, then added 4
+c. c. more, or 11.7 c. c. in total. After boiling it required 5.3 c. c.
+to bring back a slight pink, the total alkalinity would be 11.7 c. c. -
+5.3 c. c. = 6.4 c. c., or 0.64% total alkali in the lye in terms of
+caustic soda. If there were 40,000 pounds of lye to be treated then we
+should have to neutralize:
+
+40,000 x .0064 = 256 lbs. alkali. Since sulfate of alumina neutralizes
+one-third of its weight in caustic, and there are say 9 lbs. of this
+added per thousand pounds of lye we would add
+
+40,000 x 9 = 360 lbs. of sulfate of alumina. This would neutralize 360 x
+1/3 = 120 lbs of alkali. There are then 256 - 120 = 136 lbs. of alkali
+still to be neutralized. If 60deg. B. sulfuric acid is used it requires
+about 1.54 lbs. of acid to one pound of caustic. Therefore to neutralize
+the caustic soda remaining it requires:
+
+136 x 1.54 = 209.44 lbs. 60deg. B. sulfuric acid to neutralize the total
+alkali in the 40,000 pounds of spent lye.
+
+The acid is added and the lye well stirred, after which another sample
+is taken and again titrated as before. From this titration the amount of
+acid to be added is again calculated and more acid is added if
+necessary. Should too much acid have been added, caustic soda solution
+is added until the lye is between exactly neutral and 0.02% alkaline.
+The filtered lyes at this stage have a slight yellowish cast.
+
+To be sure that the lyes are treated correctly the precipitation test is
+advisable. To carry this out filter about 50 c. c. of the treated lye
+and divide into two portions in a test tube. To one portion add ammonia
+drop by drop. If a cloudiness develops upon shaking, more alkali is
+added to the lye in the tank. To the other portion add a few drops of 1
+to 5 sulfuric acid and shake the test tube. If a precipitate develops or
+the solution clouds, more acid is needed. When the lyes are treated
+right no cloudiness should develop either upon adding ammonia or the
+dilute acid.
+
+The properly treated lye is then run through the filter press while
+slightly warm and the filtered lye is fed to the evaporator from the
+filtered lye tank. The lye coming from the filter press should be clear
+and have a slight yellowish cast. As the pressure increases it is
+necessary to clean the press or some of the press cake will pass through
+the cloths. Where sodium silicate is used as a filler, the silicate
+scrap should never be returned to the soap kettle until the glycerine
+lyes have been withdrawn. This practice of some soapmakers is to be
+strongly censured, as it causes decided difficulty in filtering the lye,
+since during the treatment of the lye, free silicic acid in colloidal
+form is produced by the decomposition of the sodium silicate by acid.
+This often prevents filtering the treated lye even at excess pressure
+and at its best retards the filtering.
+
+As to the filter press cake, this may be best thrown away in a small
+factory. Where, however, the output of glycerine is very large it pays
+to recover both the fatty acids and alumina in the press cakes.
+
+In some cases, especially when the lyes are very dirty and the total
+residue in the crude glycerine runs high, for which there is a penalty
+usually attached, a double filtration of the lye is advisable. This is
+carried out by first making the lye slightly acid in reaction by the
+addition of alum and acid, then filtering. This filtered lye is then
+neutralized to the proper point with caustic, as already described, and
+passed through the filter press again.
+
+While in the method of treating the lyes as given sulfuric acid is used
+for neutralizing, some operators prefer to use hydrochloric acid, as
+this forms sodium chloride or common salt, whereas sulfuric acid forms
+sodium sulfate, having 3/5 the graining power of salt, which eventually
+renders the salt useless for graining the soap, as the percentage of
+sodium sulfate increases in the salt. When the salt contains 25 per
+cent. sodium sulfate it is advisable to throw it away. Sulfuric acid,
+however, is considerably cheaper than hydrochloric and this more than
+compensates the necessity of having to eventually reject the recovered
+salt. It may here also be mentioned that recovered salt contains 5-7 per
+cent. glycerine which should be washed out in the evaporator before it
+is thrown away. The following tables give the approximate theoretical
+amounts of acids of various strengths required to neutralize one pound
+of caustic soda:
+
+For 1 pound of caustic soda--
+
+    3.25 lbs. 18deg. B. hydrochloric (muriatic) acid are required.
+    2.92  "   20deg. B.      "            "       "   "     "
+    2.58  "   22deg. B.      "            "       "   "     "
+
+For 1 pound of caustic soda--
+
+    1.93 lbs. 50deg. B. sulphuric acid are required.
+    1.54  "   60deg. B.     "      "    "     "
+    1.28  "   66deg. B.     "      "    "     "
+
+It is, of course, feasible to neutralize the spent lye without first
+determining the causticity by titrating a sample and this is often the
+case. The operator under such conditions first adds the sulfate of
+alumina, then the acid, using litmus paper as his indicator.
+Comparatively, this method of treatment is much slower and not as
+positive, as the amount of acid or alkali to be added is at all times
+uncertain, for in the foaming of the lyes their action on litmus is
+misleading.
+
+After the lye has been filtered to the filtered lye tank it is fed to
+the evaporator, the method of operation of which varies somewhat with
+different styles or makes. When it first enters the evaporator the lye
+is about 11deg.-12deg. B. After boiling the density will gradually rise
+to 27deg. B. and remain at this gravity for some time and during which
+time most of the salt is dropped out in the salt filter. As the lye
+concentrates the gravity gradually rises to 28deg.-30deg. B., which is
+half crude glycerine and contains about 60 per cent. glycerine. Some
+operators carry the evaporation to this point and accumulate a quantity
+of half crude before going on to crude. After half crude is obtained the
+temperature on the evaporator increases, the vacuum increases and the
+pressure on the condensation drain goes up (using the same amount of
+live steam). As the liquor grows heavier the amount of evaporation is
+less, and less steam is required necessitating the regulation of the
+steam pressure on the drum. When a temperature of 210deg. F. on the
+evaporator, with 26 or more inches vacuum on the pump is arrived at, the
+crude stage has been reached and the liquor now contains about 80 per
+cent. glycerine in which shape it is usually sold by soap manufacturers.
+A greater concentration requires more intricate apparatus. After
+settling a day in the crude tank it is drummed.
+
+Crude glycerine (about 80 per cent. glycerol) free from salt is 33deg.
+B., or has a specific gravity of 1.3. A sample boiled in an open dish
+boils at a temperature of 155deg. C. or over.
+
+
+TWITCHELL PROCESS.
+
+The Twitchell process of saponification consists of causing an almost
+complete cleavage of fats and oils by the use of the Twitchell reagent
+or saponifier, a sulfo-aromatic compound. This is made by the action of
+concentrated sulfuric acid upon a solution of oleic acid or stearic acid
+in an aromatic hydrocarbon. From 0.5 per cent. to 3 per cent. of the
+reagent is added and saponification takes place from 12-48 hours by
+heating in a current of live steam. The reaction is usually accelerated
+by the presence of a few per cent. of free fatty acids as a starter.
+Recently the Twitchell double reagent has been introduced through which
+it is claimed that better colored fatty acids are obtained and the
+glycerine is free from ash.
+
+The advantages claimed for the Twitchell process as outlined by
+Joslin[12] are as follows:
+
+1. All the glycerine is separated from the stock before entering the
+kettle, preventing loss of glycerine in the soap and removing glycerine
+from spent lye.
+
+2. The liquors contain 15-20 per cent. glycerine whereas spent lyes
+contain but 3-5 per cent. necessitating less evaporation and
+consequently being more economical in steam, labor and time.
+
+3. No salt is obtained in the liquors which makes the evaporation
+cheaper and removes the cause of corrosion of the evaporator; also
+saves the glycerine retained by the salt.
+
+4. The glycerine liquors are purer and thus the treatment of the lyes is
+cheaper and simpler and the evaporation less difficult.
+
+5. The glycerine can readily be evaporated to 90 per cent. crude rather
+than 80 per cent. crude, thus saving drums, labor in handling and
+freight. The glycerine furthermore receives a higher rating and price,
+being known as saponification crude which develops no glycols in
+refining it.
+
+6. The fatty acids obtained by the Twitchell saponifier may be converted
+into soap by carbonates, thus saving cost in alkali.
+
+7. There is a decrease in the odor of many strong smelling stocks.
+
+8. The glycerine may be obtained from half boiled and cold made soaps as
+well as soft (potash) soaps.
+
+While the advantages thus outlined are of decided value in the
+employment of the Twitchell process, the one great disadvantage is that
+the fatty acids obtained are rather dark in color and are not
+satisfactorily employed for the making of a soap where whiteness of
+color is desired.
+
+To carry out the process the previously heated oil or fat to be
+saponified is run into a lead lined tank. As greases and tallow often
+contain impurities a preliminary treatment with sulfuric acid is
+necessary. For a grease 1.25 per cent. of half water and half 66deg. B.
+sulfuric acid is the approximate amount. The undiluted 66deg. B. acid
+should never be added directly, as the grease would be charred by this.
+The grease should be agitated by steam after the required percentage of
+acid, calculated on the weight of the grease, has been added. The wash
+lye coming off should be 7deg.-10deg. B. on a good clean grease or
+15deg.-22deg. B. on cotton oil or a poor grease. As has been stated the
+grease is heated before the acid is added or the condensation of the
+steam necessitates the addition of more acid. After having boiled for
+1-2 hours the grease is allowed to settle for 12 hours and run off
+through a swivel pipe.
+
+After the grease has been washed, as just explained, and settled, it is
+pumped into a covered wooden tank containing an open brass coil. Some of
+the second lye from a previous run is usually left in this tank and the
+grease pumped into this. The amount of this lye should be about
+one-third to one-half the weight of the grease so that there is about 60
+per cent. by weight of grease in the tank after 24 hours boiling. Where
+occasions arise when there is no second lye about 50 per cent. by weight
+of distilled water to the amount of grease is run into the tank to
+replace the lye. The saponifier is then added through a glass or granite
+ware funnel after the contents of the tank have been brought to a boil.
+If the boiling is to be continued 48 hours, 1 per cent. of saponifier is
+added. For 24 hours boiling add 1.5 per cent. The boiling is continued
+for 24-48 hours allowing 18 inches for boiling room or the grease will
+boil over.
+
+After boiling has continued the required length of time the mass is
+settled and the glycerine water is drawn off to the treatment tank.
+Should a permanent emulsion have formed, due to adding too great an
+amount of saponifier, a little sulfuric acid (0.1 per cent.-0.3 per
+cent.) will readily break this. During the time this is being done the
+space between the grease and the cover on the tank is kept filled with
+steam as contact with the air darkens the fatty acids.
+
+To the grease remaining in the tank distilled water (condensed water
+from steam coils) to one-half its volume is added and the boiling
+continued 12-24 hours. The grease is then settled and the clear grease
+run off through a swivel pipe. A layer of emulsion usually forms between
+the clear grease and lye so that it may easily be determined when the
+grease has all been run off. To prevent discoloration of the fatty acids
+it is necessary to neutralize the lye with barium carbonate. The amount
+of this to be added depends upon the percentage of saponifier used.
+About 1/10 the weight of saponifier is the right amount. The barium
+carbonate is added through the funnel at the top of the tank mixed with
+a little water and the lye tested until it is neutral to methyl orange
+indicator. When the fatty acids are thus treated they will not darken
+upon exposure to the air when run off.
+
+Fresh grease is now pumped into the lye or water remaining in the tank
+and the process repeated.
+
+The glycerine water or first lye is run to the treatment tank, the fat
+skimmed off and neutralized with lime until it shows pink with
+phenolphthalein, after having been thoroughly boiled with steam. About
+0.25 per cent. lime is the proper amount to add. The mixture is then
+allowed to settle and the supernatant mixture drawn off and run to the
+glycerine evaporator feed tank. The lime which holds considerable
+glycerine is filtered and the liquor added to the other. The evaporation
+is carried out in two stages. The glycerine water is first evaporated to
+about 60 per cent. glycerol, then dropped into a settling tank to settle
+out the calcium sulfate. The clear liquor is then evaporated to crude
+(about 90 per cent. glycerine) and the sediment filtered and also
+evaporated to crude.
+
+As to the amount of saponifier to use on various stocks, this is best
+determined by experiment as to how high a percentage gives dark colored
+fatty acids. For good stock such as clean tallow, prime cottonseed oil,
+corn oil, cocoanut oil and stock of this kind 0.75 per cent. saponifier
+is sufficient. For poorer grades of tallow, house grease, poor
+cottonseed oil, etc., 1 per cent. saponifier is required and for poorer
+grade greases higher percentages. The percentage of fatty acids
+developed varies in various stocks, and also varies with the care that
+the operation is carried out, but is usually between 85 per cent.-95 per
+cent. Due to the water taken up in the saponification process there is a
+yield of about 103 pounds of fatty acids and glycerine for 100 pounds of
+fat.
+
+The Twitchell reagent has undoubtedly caused a decided advance in the
+saponification of fats and oils and has been of great value to the soap
+manufacturer, because with a small expenditure it is possible to compete
+with the much more expensive equipment necessary for autoclave
+saponification. The drawback, however, has been that the reagent
+imparted a dark color to the fatty acids obtained, due to decomposition
+products forming when the reagent is made, and hence is not suitable for
+use in soaps where whiteness of color is desired.
+
+There have recently been two new reagents introduced which act as
+catalyzers in splitting fats, just as the Twitchell reagent acts, but
+the fatty acids produced by the cleavage are of good color. The
+saponification, furthermore, takes place more rapidly. These are the
+Pfeilring reagent and Kontact reagent.
+
+The Pfeilring reagent is very similar to the Twitchell reagent, being
+made from hydrogenated castor oil and naphthalene by sulfonation with
+concentrated sulfuric acid. It is manufactured in Germany and is being
+extensively used in that country with good success.
+
+The Kontact or Petroff reagent, discovered by Petroff in Russia, is made
+from sulfonated mineral oils. Until very recently it has only been
+manufactured in Europe, but now that it has been found possible to
+obtain the proper mineral constituent from American petroleum, it is
+being manufactured in this country, and it is very probable that it will
+replace the Twitchell reagent because of the advantages derived by using
+it, as compared to the old Twitchell reagent.
+
+The method and equipment necessary for employing either the Pfeilring or
+Kontact reagents is exactly the same as in using the Twitchell process.
+
+
+AUTOCLAVE SAPONIFICATION.
+
+While the introduction of the Twitchell process to a great extent
+replaced the autoclave method of saponification for obtaining fatty
+acids for soap making, the autoclave method is also used. This process
+consists in heating the previously purified fat or oil in the presence
+of lime and water, or water only, for several hours, which causes a
+splitting of the glycerides into fatty acids and glycerine. The
+advantage of autoclave saponification over the Twitchell process is that
+a greater cleavage of the fats and oils results in less time and at a
+slightly less expense. The glycerine thus obtained is also purer and of
+better color than that obtained by Twitchelling the fats.
+
+An autoclave or digestor consists of a strongly constructed, closed
+cylindrical tank, usually made of copper, and is so built as to resist
+internal pressure. The digestor is usually 3 to 5 feet in diameter and
+from 18 to 25 feet high. It may be set up horizontally or vertically and
+is covered with an asbestos jacket to retain the heat. Various inlets
+and outlets for the fats, steam, etc., as well as a pressure gauge and
+safety valve are also a necessary part of the equipment.
+
+
+LIME SAPONIFICATION.
+
+The saponification in an autoclave is usually carried out by introducing
+the fats into the autoclave with a percentage of lime, magnesia or zinc
+oxide, together with water. If the fats contain any great amount of
+impurities, it is first necessary to purify them either by a treatment
+with weak sulfuric acid, as described under the Twitchell process, or by
+boiling them up with brine and settling out the impurities from the hot
+fat.
+
+To charge the autoclave a partial vacuum is created therein by
+condensation of steam just before running the purified oil in from an
+elevated tank. The required quantity of unslaked lime, 2 to 4 per cent.
+of the weight of the fat, is run in with the molten fat, together with
+30 per cent. to 50 per cent. of water. While 8.7 per cent. lime is
+theoretically required, practice has shown that 2 per cent. to 4 per
+cent. is sufficient. The digestor, having been charged and adjusted,
+steam is turned on and a pressure of 8 to 10 atmospheres maintained
+thereon for a period of six to ten hours. Samples of the fat are taken
+at various intervals and the percentage of free fatty acids determined.
+When the saponification is completed the contents of the autoclave are
+removed, usually by blowing out the digestor into a wooden settling
+tank, or by first running off the glycerine water and then blowing out
+the lime, soap and fatty acids. The mass discharged from the digestor
+separates into two layers, the upper consisting of a mixture of lime
+soap or "rock" and fatty acids, and the lower layer contains the
+glycerine or "sweet" water. The glycerine water is first run off through
+a clearing tank or oil separator, if this has not been done directly
+from the autoclave, and the mass remaining washed once or twice more
+with water to remove any glycerine still retained by the lime soap. The
+calculated amount of sulfuric acid to decompose the lime "rock" is then
+added, and the mass agitated until the fatty acids contained therein are
+entirely set free. Another small wash is then given and the wash water
+added to the glycerine water already run off. The glycerine water is
+neutralized with lime, filtered and concentrated as in the Twitchell
+process.
+
+Due to the difficulties of working the autoclave saponification with
+lime, decomposing the large amount of lime soap obtained and dealing
+with much gypsum formed thereby which collects as a sediment and
+necessitates cleaning the tanks, other substances are used to replace
+lime. Magnesia, about 2 per cent. of the weight of the fat, is used and
+gives better results than lime. One-half to 1 per cent. of zinc oxide of
+the weight of the fat is even better adapted and is now being
+extensively employed for this purpose. In using zinc oxide it is
+possible to recover the zinc salts and use them over again in the
+digestor, which makes the process as cheap to work as with lime, with
+far more satisfactory results.
+
+
+ACID SAPONIFICATION.
+
+While it is possible to saponify fats and oils in an autoclave with the
+addition of acid to the fat, unless a specially-constructed digestor is
+built, the action of the acid on the metal from which the autoclave is
+constructed prohibits its use. The acid saponification is therefore
+carried out by another method.
+
+The method of procedure for acid saponification, therefore, is to first
+purify the fats with dilute acid as already described. The purified, hot
+or warm, dry fat is then run to a specially-built acidifier or a
+lead-lined tank and from 4 per cent. to 6 per cent. of concentrated
+sulfuric acid added to the fat, depending upon its character, the degree
+of saponification required, temperature and time of saponification. A
+temperature of 110 degrees C. is maintained and the mass mixed from four
+to six hours. The tank is then allowed to settle out the tar formed
+during the saponification, and the fatty acids run off to another tank
+and boiled up about three times with one-third the amount of water. The
+water thus obtained contains the glycerine, and after neutralization is
+concentrated.
+
+
+AQUEOUS SAPONIFICATION.
+
+While lime or a similar substance is ordinarily used to aid in splitting
+fats in an autoclave, the old water process is still used. This is a
+convenient, though slower and more dangerous method, of producing the
+hydrolysis of the glyceride, as well as the simplest in that fatty acids
+and glycerine in a water solution are obtained. The method consists in
+merely charging the autoclave with fats and adding about 30 per cent. to
+40 per cent. of their weight of water, depending on the amount of free
+fatty acid and subjecting the charge to a pressure of 150 to 300 pounds,
+until the splitting has taken place. This is a much higher pressure than
+when lime is used and therefore a very strong autoclave is required.
+Since fatty acids and pure glycerine water are obtained no subsequent
+treatment of the finished charge is necessary except separating the
+glycerine water and giving the fatty acids a wash with water to remove
+all the glycerine from them.
+
+
+SPLITTING FATS WITH FERMENTS.
+
+In discussing the causes of rancidity of oils and fats it was pointed
+out that the initial splitting of these is due to enzymes, organized
+ferments. In the seeds of the castor oil plant, especially in the
+protoplasm of the seed, the enzyme which has the property of causing
+hydrolysis of the glycerides is found. The ferment from the seeds of the
+castor oil plant is now extracted and used upon a commercial basis for
+splitting fats.
+
+The equipment necessary to carry out this method of saponification is a
+round, iron, lead-lined tank with a conical bottom, preferably about
+twice as long as it is wide. Open and closed steam coils are also
+necessary in the tank.
+
+The oils are first heated and run into this tank. The right temperature
+to heat these to is about 1 degree to 2 degrees above their
+solidification point. For liquid oils 23 degrees C. is the proper heat
+as under 20 degrees C. the cleavage takes place slowly. Fats titering 44
+degrees C. or above must be brought down in titer by mixing with them
+oils of a lower titer as the ferment or enzyme is killed at about 45
+degrees C. and thus loses its power of splitting. It is also necessary
+to have the fat in the liquid state or the ferment does not act. The
+proper temperature must be maintained with dry steam.
+
+It is, of course, necessary to add water, which may be any kind desired,
+condensed, water from steam coils, well, city, etc. From 30 per cent. to
+40 per cent., on the average 35 per cent. of water is added, as the
+amount necessary is regulated so as to not dilute the glycerine water
+unnecessarily. To increase the hydrolysis a catalyzer, some neutral
+salt, usually manganese sulfate is added in the proportion of 0.15 per
+cent. appears to vary directly as the saponification number of the fat
+or oil. The approximate percentages of fermentive substance to be added
+to various oils and fats follow:
+
+    Cocoanut oil          8   %
+    Palm Kernel oil       8   %
+    Cottonseed oil        6-7 %
+    Linseed oil           4-5 %
+    Tallow oil            8-10%
+
+The oil, water, manganese sulfate and ferment having been placed in the
+tank in the order named, the mixture is agitated with air for about a
+quarter of an hour to form an even emulsion, in which state the mass is
+kept by stirring occasionally with air while the saponification is
+taking place. A temperature is maintained a degree or two above the
+titer point of the fat with closed steam which may be aided by covering
+the tank for a period of 24 to 48 hours. The splitting takes place
+rapidly at first, then proceeds more slowly. In 24 hours 80 per cent. of
+the fats are split and in 48 hours 85 per cent. to 90 per cent.
+
+When the cleavage has reached the desired point the mass is heated to 80
+degrees-85 degrees C. with live or indirect steam while stirring with
+air. Then 0.1 per cent.-0.15 per cent of concentrated sulfuric acid
+diluted with water is added to break the emulsion. When the emulsion is
+broken the glycerine water is allowed to settle out and drawn off. The
+glycerine water contains 12 per cent. to 25 per cent. glycerine and
+contains manganese sulfate, sulfuric acid and albuminous matter. Through
+neutralization with lime at boiling temperature and filtration the
+impurities can almost all be removed after which the glycerine water may
+be fed to the evaporator. Should it be desired to overcome the trouble
+due to the gypsum formed in the glycerine, the lime treatment may be
+combined with a previous treatment of the glycerine water with barium
+hydrate to remove the sulfuric acid, then later oxalic acid to
+precipitate the lime.
+
+The fatty acids obtained by splitting with ferments are of very good
+color and adaptable for soap making.
+
+
+KREBITZ PROCESS.
+
+The Krebitz process which has been used to some extent in Europe is
+based upon the conversion of the fat or oil into lime soap which is
+transformed into the soda soap by the addition of sodium carbonate. To
+carry out the process a convenient batch of, say, 10,000 pounds of fat
+or oil, is run into a shallow kettle containing 1,200 to 1,400 pounds of
+lime previously slaked with 3,700 to 4,500 pounds of water. The mass is
+slowly heated with live steam to almost boiling until an emulsion is
+obtained. The tank is then covered and allowed to stand about 12 hours.
+The lime soap thus formed is dropped from the tank into the hopper of a
+mill, finely ground and conveyed to a leeching tank. The glycerine is
+washed out and the glycerine water run to a tank for evaporation. The
+soap is then further washed and these washings are run to other tanks to
+be used over again to wash a fresh batch of soap. About 150,000 pounds
+of water will wash the soap made from 10,000 pounds of fat which makes
+between 15,000 and 16,000 pounds of soap. The first wash contains
+approximately 10 per cent. glycerine and under ordinary circumstances
+this only need be evaporated for glycerine recovery.
+
+After extracting the glycerine the soap is slowly introduced into a
+boiling solution of sodium carbonate or soda ash and boiled until the
+soda has replaced the lime. This is indicated by the disappearance of
+the small lumps of lime soap. Caustic soda is then added to saponify the
+fat not converted by the lime saponification. The soap is then salted
+out and allowed to settle out the calcium carbonate. This drops to the
+bottom of the kettle as a heavy sludge entangling about 10 per cent. of
+the soap. A portion of this soap may be recovered by agitating the
+sludge with heat and water, pumping the soap off the top and filtering
+the remaining sludge.
+
+While the soap thus obtained is very good, the percentage of glycerine
+recovered is greatly increased and the cost of alkali as carbonate is
+less. The disadvantages are many. Large quantities of lime are required;
+it is difficult to recover the soap from the lime sludge; the operations
+are numerous prior to the soap making proper and rather complicated
+apparatus is required.
+
+
+DISTILLATION OF FATTY ACIDS.
+
+The fatty acids obtained by various methods of saponification may be
+further improved by distillation.
+
+In order to carry out this distillation, two methods may be pursued,
+first, the continuous method, whereby the fatty acids are continually
+distilled for five to six days, and, second, the two phase method,
+whereby the distillation continues for 16 to 20 hours, after which the
+residue is drawn off, treated with acid, and its distillate added to a
+fresh charge of fatty acids. The latter method is by far the best, since
+the advantages derived by thus proceeding more than compensate the
+necessity of cleaning the still. Better colored fatty acids are
+obtained; less unsaponifiable matter is contained therein; there is no
+accumulation of impurities; the amount of neutral fat is lessened
+because the treatment of the tar with acid causes a cleavage of the
+neutral fat and the candle tar or pitch obtained is harder and better
+and thus more valuable.
+
+The stills are usually built of copper, which are heated by both direct
+fire and superheated steam. Distillation under vacuum is advisable. To
+begin the distilling operation, the still is first filled with dry hot
+fatty acids to the proper level. Superheated steam is then admitted and
+the condenser is first heated to prevent the freezing of the fatty
+acids, passing over into same. When the temperature reaches 230 deg. C.
+the distillation begins. At the beginning, the fatty acids flow from the
+condenser, an intense green color, due to the formation of copper soaps
+produced by the action of the fatty acids on the copper still. This
+color may easily be removed by treating with dilute acid to decompose
+the copper soaps.
+
+In vacuum distillation, the operation is begun without the use of
+vacuum. Vacuum is introduced only when the distillation has proceeded
+for a time and the introduction of this must be carefully regulated,
+else the rapid influence of vacuum will cause the contents of the still
+to overflow. When distillation has begun a constant level of fatty acids
+is retained therein by opening the feeding valve to same, and the heat
+is so regulated as to produce the desired rate of distillation. As soon
+as the distillate flows darker and slower, the feeding valve to the
+still is shut off and the distillation continued until most of the
+contents of the still are distilled off, which is indicated by a rise in
+the temperature. Distillation is then discontinued, the still shut down,
+and in about an hour the contents are sufficiently cool to be emptied.
+The residue is run off into a proper receiving vessel, treated with
+dilute acid and used in the distillation of tar.
+
+In the distillation of tar the same method as the above is followed,
+only distillation proceeds at a higher temperature. The first portion
+and last portion of the distillate from tar are so dark that it is
+necessary to add them to a fresh charge of fatty acids. By a well
+conducted distillation of tar about 50 per cent. of the fatty acids from
+the tar can be used to mix with the distilled fatty acids. The residue
+of this operation called stearine pitch or candle tar consists of a
+hard, brittle, dark substance. Elastic pitch only results where
+distillation has been kept constant for several days without
+interrupting the process, and re-distilling the tar. In a good
+distillation the distillation loss is 0.5 to 1.5% and loss in pitch
+1.5%. Fatty acids which are not acidified deliver about 3% of pitch.
+Very impure fats yield even a higher percentage in spite of acidifying.
+For a long time it was found impossible to find any use for stearine
+pitch, but in recent years a use has been found for same in the
+electrical installation of cables.
+
+FOOTNOTES:
+
+[12] Journ. Ind. Eng. Chem. (1909), I, p. 654.
+
+
+
+
+CHAPTER VI
+
+Analytical Methods.
+
+
+While it is possible to attain a certain amount of efficiency in
+determining the worth of the raw material entering into the manufacture
+of soap through organoleptic methods, these are by no means accurate. It
+is, therefore, necessary to revert to chemical methods to correctly
+determine the selection of fats, oil or other substances used in soap
+making, as well as standardizing a particular soap manufactured and to
+properly regulate the glycerine recovered.
+
+It is not our purpose to cover in detail the numerous analytical
+processes which may be employed in the examination of fats and oils,
+alkalis, soap and glycerine, as these are fully and accurately covered
+in various texts, but rather to give briefly the necessary tests which
+ought to be carried out in factories where large amounts of soap are
+made. Occasion often arises where it is impossible to employ a chemist,
+yet it is possible to have this work done by a competent person or to
+have someone instruct himself as just how to carry out the more simple
+analyses, which is not a very difficult matter. The various standard
+solutions necessary to carrying out the simpler titrations can readily
+be purchased from dealers in chemical apparatus and it does not take
+extraordinary intelligence for anyone to operate a burette, yet in many
+soap plants in this country absolutely no attention is paid to the
+examining of raw material, though many thousand pounds are handled
+annually, which, if they were more carefully examined would result in
+the saving of much more money than it costs to examine them or have
+them at least occasionally analyzed.
+
+
+ANALYSIS OF FATS AND OILS.
+
+In order to arrive at proper results in the analysis of a fat or oil, it
+is necessary to have a proper sample. To obtain this a sample of several
+of the packages of oil or fat is taken and these mixed or molten
+together into a composite sample which is used in making the tests. If
+the oil or fat is solid, a tester is used in taking the sample from the
+package and if they are liquid, it is a simple matter to draw off a
+uniform sample from each package and from these to form a composite
+sample.
+
+In purchasing an oil or fat for soap making, the manufacturer is usually
+interested in the amount of free fatty acid contained therein, of
+moisture, the titer, the percentage of unsaponifiable matter and to
+previously determine the color of soap which will be obtained where
+color is an object.
+
+
+DETERMINATION OF FREE FATTY ACIDS.
+
+Since the free fatty acid content of a fat or oil represents a loss of
+glycerine, the greater the percentage of free fatty acid, the less
+glycerine is contained in the fat or oil, it is advisable to purchase a
+fat or oil with the lower free acid, other properties and the price
+being the same.
+
+While the mean molecular weight of the mixed free fatty acids varies
+with the same and different oils or fats and should be determined for
+any particular analysis for accuracy, the free fatty acid is usually
+expressed as oleic acid, which has a molecular weight of 282.
+
+To carry out the analysis 5 to 20 grams of the fat are weighed out into
+an Erlenmeyer flask and 50 cubic centimeters of carefully neutralized
+alcohol are added. In order to neutralize the alcohol add a few drops of
+phenolphthalein solution to same and add a weak caustic soda solution
+drop by drop until a very faint pink color is obtained upon shaking or
+stirring the alcohol thoroughly. The mixture of fat and neutralized
+alcohol is then heated to boiling and titrated with tenth normal alkali
+solution, using phenolphthalein as an indicator. As only the free fatty
+acids are readily soluble in the alcohol and the fat itself only
+slightly mixes with it, the flask should be well agitated toward the end
+of the titration. When a faint pink color remains after thoroughly
+agitating the flask the end point is reached. In order to calculate the
+percentage of free fatty acid as oleic acid, multiply the number of
+cubic centimeters of tenth normal alkali used as read on the burette by
+0.0282 and divide by the number of grams of fat taken for the
+determination and multiply by 100.
+
+When dark colored oils or fats are being titrated it is often difficult
+to obtain a good end point with phenolphthalein. In such cases about 2
+cubic centimeters of a 2 per cent. alcoholic solution of Alkali Blue 6 B
+is recommended.
+
+Another method of directly determining the free fatty acid content of
+tallow or grease upon which this determination is most often made is to
+weigh out into an Erlenmeyer flask exactly 5.645 grams of a sample of
+tallow or grease. Add about 75 cubic centimeters of neutralized alcohol.
+Heat until it boils, then titrate with tenth normal alkali and divide
+the reading by 2, which gives the percentage of free fatty acid as
+oleic. If a fifth normal caustic solution is used, the reading on the
+burette gives the percentage of free fatty acid directly. This method,
+while it eliminates the necessity of calculation, is troublesome in that
+it is difficult to obtain the exact weight of fat.
+
+
+MOISTURE.
+
+To calculate the amount of moisture contained in a fat or oil 5 to 10
+grams are weighed into a flat bottom dish, together with a known amount
+of clean, dry sand, if it is so desired. The dish is then heated over a
+water bath, or at a temperature of 100-110 degs. C., until it no longer
+loses weight upon drying and reweighing the dish. One hour should elapse
+between the time the dish is put on the water bath and the time it is
+taken off to reweigh. The difference between the weight of the dish is
+put on the water bath and the time it is taken off when it reaches a
+constant weight is moisture. This difference divided by the original
+weight of the fat or oil x 100 gives the percentage of moisture.
+
+When highly unsaturated fats or oils are being analyzed for moisture, an
+error may be introduced either by the absorption of oxygen, which is
+accelerated at higher temperature, or by the formation of volatile fatty
+acids. The former causes an increase in weight, the latter causes a
+decrease. To obviate this, the above operation of drying should be
+carried out in the presence of some inert gas like hydrogen, carbon
+dioxide, or nitrogen.
+
+
+TITER.
+
+The titer of a fat or oil is really an indication of the amount of
+stearic acid contained therein. The titer, expressed in degrees
+Centigrade, is the solidification point of the fatty acids of an oil or
+fat. In order to carry out the operation a Centigrade thermometer
+graduated in one or two-tenths of a degree is necessary. A thermometer
+graduated between 10 degs. centigrade to 60 degs. centigrade is best
+adapted and the graduations should be clear cut and distinct.
+
+To make the determination about 30 grams of fat are roughly weighed in a
+metal dish and 30-40 cubic centimeters of a 30 per cent. (36 degs.
+Baume) solution of sodium hydroxide, together with 30-40 cubic
+centimeters of alcohol, denatured alcohol will do, are added and the
+mass heated until saponified. Heat over a low flame or over an asbestos
+plate until the soap thus formed is dry, constantly stirring the
+contents of the dish to prevent burning. The dried soap is then
+dissolved in about 1000 cubic centimeters of water, being certain that
+all the alcohol has been expelled by boiling the soap solution for about
+half an hour. When the soap is in solution add sufficient sulphuric acid
+to decompose the soap, approximately 100 cubic centimeters of 25 degs.
+Baume sulphuric acid, and boil until the fatty acids form a clear layer
+on top of the liquid. A few pieces of pumice stone put into the mixture
+will prevent the bumping caused by boiling. Siphon off the water from
+the bottom of the dish and wash the fatty acids with boiling water until
+free from sulphuric acid. Collect the fatty acids in a small casserole
+or beaker and dry them over a steam bath or drying oven at 110 degs.
+Centigrade. When the fatty acids are dry, cool them to about 10 degs.
+above the titer expected and transfer them to a titer tube or short test
+tube which is firmly supported by a cork in the opening of a salt mouth
+bottle. Hang the thermometer by a cord from above the supported tube so
+it reaches close to the bottom when in the titer tube containing the
+fatty acids and so that it may be used as a stirrer. Stir the mass
+rather slowly, closely noting the temperature. The temperature will
+gradually fall during the stirring operation and finally remain
+stationary for half a minute or so then rise from 0.1 to 0.5 degs. The
+highest point to which the mercury rises after having been stationary is
+taken as the reading of the titer.
+
+
+DETERMINATION OF UNSAPONIFIABLE MATTER.
+
+In order to determine the unsaponifiable matter in fats and oils they
+are first saponified, then the unsaponifiable, which consists mainly of
+hydrocarbons and the higher alcohols cholesterol or phytosterol, is
+extracted with ether or petroleum ether, the ether evaporated and the
+residue weighed as unsaponifiable.
+
+To carry out the process first saponify about 5 grams of fat or oil with
+an excess of alcoholic potassium hydrate, 20-30 cubic centimeters of a 1
+to 10 solution of potassium hydroxide in alcohol until the alcohol is
+evaporated over a steam bath. Wash the soap thus formed into a
+separatory funnel of 200 cubic centimeters capacity with 80-100 cubic
+centimeters water. Then add about 60 cubic centimeters of ether,
+petroleum ether or 86 degs. gasoline and thoroughly shake the funnel to
+extract the unsaponifiable. Should the two layers not separate readily,
+add a few cubic centimeters of alcohol, which will readily cause them to
+separate. Draw off the watery solution from beneath and wash the ether
+with water containing a few drops of sodium hydrate and run to another
+dish. Pour the watery solution into the funnel again and repeat the
+extraction once or twice more or until the ether shows no discoloration.
+Combine the ether extractions into the funnel and wash with water until
+no alkaline reaction is obtained from the wash water. Run the ether
+extract to a weighed dish, evaporate and dry rapidly in a drying oven.
+As some of the hydrocarbons are readily volatile at 100 degs.
+Centigrade, the drying should not be carried on any longer than
+necessary. The residue is then weighed and the original weight of fat
+taken divided into the weight of the residue x 100 gives the percentage
+unsaponifiable.
+
+
+TEST FOR COLOR OF SOAP.
+
+It is often desirable to determine the color of the finished soap by a
+rapid determination before it is made into soap. It often happens,
+especially with the tallows, that a dark colored sample produces a light
+colored soap, whereas a bleached light colored tallow produces a soap
+off shade.
+
+To rapidly determine whether the color easily washes out of the tallow
+with lye, 100 cubic centimeters of tallow are saponified in an enameled
+or iron dish with 100 cubic centimeters of 21 degs. Baume soda lye and
+100 cubic centimeters of denatured alcohol. Continue heating over a wire
+gauze until all the alcohol is expelled and then add 50 cubic
+centimeters of the 21 degs. Baume lye to grain the soap. Allow the lyes
+to settle and with an inverted pipette draw off the lyes into a test
+tube or bottle. Close the soap with 100 cubic centimeters of hot water
+and when closed again grain with 50 cubic centimeters of the lye by just
+bringing to a boil over an open flame. Again allow the lyes to settle
+and put aside a sample of the lye for comparison. Repeat the process of
+closing, graining and settling and take a sample of lye. If the lye is
+still discolored repeat the above operations again or until the lye is
+colorless. Ordinarily all the color will come out with the third lye.
+The soap thus obtained contains considerable water which makes it appear
+white. The soap is, therefore, dried to about 15 per cent. moisture and
+examined for color. The color thus obtained is a very good criterion as
+to what may be expected in the soap kettle.
+
+By making the above analyses of fats or oils the main properties as to
+their adaptability for being made into soap are determined. In some
+cases, especially where adulteration or mixtures of oils are suspected,
+it is necessary to further analyze same. The methods of carrying out
+these analyses are fully covered by various texts on fats and oils and
+we will not go into details regarding the method of procedure in
+carrying these out.
+
+
+TESTING OF ALKALIS USED IN SOAP MAKING.
+
+The alkalis entering into the manufacture of soap such as caustic soda
+or sodium hydroxide, caustic potash or potassium hydrate, carbonate of
+soda or sodium carbonate, carbonate of potash or potassium carbonate
+usually contain impurities which do not enter into combination with the
+fats or fatty acids to form soap. It is out of the question to use
+chemically pure alkalis in soap making, hence it is often necessary to
+determine the alkalinity of an alkali. It may again be pointed out that
+in saponifying a neutral fat or oil only caustic soda or potash are
+efficient and the carbonate contained in these only combines to a more
+or less extent with any free fatty acids contained in the oils or fats.
+Caustic soda or potash or lyes made from these alkalis upon exposure to
+the air are gradually converted into sodium or potassium carbonate by
+the action of the carbon dioxide contained in the air. While the amount
+of carbonate thus formed is not very great and is greatest upon the
+surface, all lyes as well as caustic alkalis contain some carbonate.
+This carbonate introduces an error in the analysis of caustic alkalis
+when accuracy is required and thus in the analysis of caustic soda or
+potash it is necessary to remove the carbonate when the true alkalinity
+as sodium hydroxide or potassium hydroxide is desired. This may be done
+by titration in alcohol which has been neutralized.
+
+In order to determine the alkalinity of any of the above mentioned
+alkalis, it is first necessary to obtain a representative sample of the
+substance to be analyzed. To do this take small samples from various
+portions of the package and combine them into a composite sample.
+Caustic potash and soda are hygroscopic and samples should be weighed at
+once or kept in a well stoppered bottle. Sodium or potassium carbonate
+can be weighed more easily as they do not rapidly absorb moisture from
+the air.
+
+To weigh the caustic soda or potash place about five grams on a watch
+glass on a balance and weigh as rapidly as possible. Wash into a 500
+cubic centimeter volumetric flask and bring to the mark with distilled
+water. Pipette off 50 cubic centimeters into a 200 cubic centimeter
+beaker, dilute slightly with distilled water, add a few drops of methyl
+orange indicator and titrate with normal acid. For the carbonates about
+1 gram may be weighed, washed into a 400 cubic centimeter beaker,
+diluted with distilled water, methyl orange indicator added and titrated
+with normal acid. It is advisable to use methyl orange indicator in
+these titrations as phenolphthalein is affected by the carbon dioxide
+generated when an acid reacts with a carbonate and does not give the
+proper end point, unless the solution is boiled to expel the carbon
+dioxide. Litmus may also be used as the indicator, but here again it is
+necessary to boil as carbon dioxide also affects this substance. As an
+aid to the action of these common indicators the following table may be
+helpful:
+
+                    _Color in     _Color in
+  _Indicator._         Acid        Alkaline       _Action of
+                    Solution._     Solution._        CO_{2}._
+
+Methyl orange       Red             Yellow       Very slightly acid
+Phenolphthalein     Colorless       Red          Acid
+Litmus              Red             Blue         Acid
+
+It may be further stated that methyl orange at the neutral point is
+orange in color.
+
+To calculate the percentage of effective alkali from the above
+titrations, it must be first pointed out that in the case of caustic
+potash or soda aliquot portions are taken. This is done to reduce the
+error necessarily involved by weighing, as the absorption of water is
+decided. Thus we had, say, exactly 5 grams which weighed 5.05 grams by
+the time it was balanced. This was dissolved in 500 cubic centimeters of
+water and 50 cubic centimeters or one tenth of the amount of the
+solution was taken, or in each 50 cubic centimeters there were 0.505
+grams of the sample. We thus reduced the error of weighing by one tenth
+provided other conditions introduce no error. In the case of the
+carbonates the weight is taken directly.
+
+One cubic centimeter of a normal acid solution is the equivalent of:
+
+                                           Grams.
+    Sodium Carbonate, Na_{2}CO_{3}        0.05305
+    Sodium Hydroxide, NaOH                0.04006
+    Sodium Oxide, Na_{2}O                 0.02905
+    Carbonate K_{2}CO_{3}                 0.06908
+    Potassium Hydroxide, KOH              0.05616
+    Potassium Oxide, K_{2}O               0.04715
+
+Hence to arrive at the alkalinity we multiply the number of cubic
+centimeters, read on the burette, by the factor opposite the terms in
+which we desire to express the alkalinity, divide the weight in grams
+thus obtained by the original weight taken, and multiply the result by
+100, which gives the percentage of alkali in the proper terms. For
+example, say, we took the 0.505 grams of caustic potash as explained
+above and required 8.7 cubic centimeter normal acid to neutralize the
+solution, then
+
+    8.7 x .05616 = .4886 grams KOH in sample
+
+    .4886
+    ----- x 100 = 96.73% KOH in sample.
+    .505
+
+Caustic potash often contains some caustic soda, and while it is
+possible to express the results in terms of KOH, regardless of any
+trouble that may be caused by this mixture in soap making, an error is
+introduced in the results, not all the alkali being caustic potash. In
+such cases it is advisable to consult a book on analysis as the analysis
+is far more complicated than those given we will not consider it. The
+presence of carbonates, as already stated, also causes an error. To
+overcome this the alkali is titrated in absolute alcohol, filtering off
+the insoluble carbonate. The soluble portion is caustic hydrate and may
+be titrated as such. The carbonate remaining on the filter paper is
+dissolved in water and titrated as carbonate.
+
+
+SOAP ANALYSIS.
+
+To obtain a sample of a cake of soap for analysis is a rather difficult
+matter as the moisture content of the outer and inner layer varies
+considerably. To overcome this difficulty a borer or sampler may be run
+right through the cake of soap, or slices may be cut from various parts
+of the cake, or the cake may be cut and run through a meat chopper
+several times and mixed. A sufficient amount of a homogeneous sample
+obtained by any of these methods is preserved for the entire analysis by
+keeping the soap in a securely stoppered bottle.
+
+The more important determinations of soap are moisture, free alkali, or
+fatty acid, combined alkali and total fatty matter. Besides these it is
+often necessary to determine insoluble matter, glycerine, unsaponifiable
+matter, rosin and sugar.
+
+
+MOISTURE.
+
+The analysis of soap for moisture, at its best, is most unsatisfactory,
+for by heating it is impossible to drive off all the water, and on the
+other hand volatile oils driven off by heat are a part of the loss
+represented as moisture.
+
+The usual method of determining moisture is to weigh 2 to 3 grams of
+finely shaved soap on a watch glass and heat in an oven at 105 degrees
+C. for 2 to 3 hours. The loss in weight is represented as water,
+although it is really impossible to drive off all the water in this way.
+
+To overcome the difficulties just mentioned either the Smith or Fahrion
+method may be used. Allen recommends Smith's method which is said to be
+truthful to within 0.25 per cent. Fahrion's method, according to the
+author, gives reliable results to within 0.5 per cent. Both are more
+rapid than the above manipulation. To carry out the method of Smith, 5
+to 10 grams of finely ground soap are heated over a sand bath with a
+small Bunsen flame beneath it, in a large porcelain crucible. The
+heating takes 20 to 30 minutes, or until no further evidence is present
+of water being driven off. This may be tested by the fogging of a cold
+piece of glass held over the crucible immediately upon removing the
+burner. When no fog appears the soap is considered dry. Any lumps of
+soap may be broken up by a small glass rod, weighed with the crucible,
+and with a roughened end to more easily separate the lumps. Should the
+soap burn, this can readily be detected by the odor, which, of course,
+renders the analysis useless. The loss in weight is moisture.
+
+By Fahrion's method[13], 2 to 4 grams of soap are weighed in a platinum
+crucible and about three times its weight of oleic acid, which has been
+heated at 120 degrees C. until all the water is driven off and preserved
+from moisture, is added and reweighed. The dish is then cautiously
+heated with a small flame until all the water is driven off and all the
+soap is dissolved. Care must be exercised not to heat too highly or the
+oleic acid will decompose. The moment the water is all driven off a
+clear solution is formed, provided no fillers are present in the soap.
+The dish is then cooled in a dessicator and reweighed. The loss in
+weight of acid plus soap is moisture and is calculated on the weight of
+soap taken. This determination takes about fifteen minutes.
+
+
+FREE ALKALI OR ACID.
+
+(_a_) _Alcoholic Method._
+
+Test a freshly cut surface of the soap with a few drops of an alcoholic
+phenolphthalein solution. If it does not turn red it may be assumed free
+fat is present; should a red color appear, free alkali is present. In
+any case dissolve 2 to 5 grams of soap in 100 cubic centimeters of
+neutralized alcohol and heat to boiling until in solution. Filter off
+the undissolved portion containing carbonate, etc., and wash with
+alcohol. Add phenolphthalein to the filtrate and titrate with N/10 acid
+and calculate the per cent. of free alkali as sodium or potassium
+hydroxide. Should the filtrate be acid instead of alkaline, titrate with
+N/10 alkali and calculate the percentage of free fatty acid as oleic
+acid.
+
+The insoluble portion remaining on the filter paper is washed with water
+until all the carbonate is dissolved. The washings are then titrated
+with N/10 sulfuric acid and expressed as sodium or potassium carbonate.
+Should borates or silicates be present it is possible to express in
+terms of these. If borax is present the carbon dioxide is boiled off
+after neutralizing exactly to methyl orange; cool, add mannite and
+phenolphthalein and titrate the boric acid with standard alkali.
+
+(_b_) _Bosshard and Huggenberg Method._[14]
+
+In using the alcoholic method for the determination of the free alkali
+or fat in soap there is a possibility of both free fat and free alkali
+being present. Upon boiling in an alcoholic solution the fat will be
+saponified, thus introducing an error in the analysis. The method of
+Bosshard and Huggenberg overcomes this objection. Their method is
+briefly as follows:
+
+_Reagents._
+
+1. N/10 hydrochloric acid to standardize N/10 alcoholic sodium
+hydroxide.
+
+2. Approximately N/10 alcoholic sodium hydroxide to fix and control the
+N/40 stearic acid.
+
+3. N/40 stearic acid. Preparation: About 7.1 grams of stearic acid are
+dissolved in one liter of absolute alcohol, the solution filtered, the
+strength determined by titration against N/10 NaOH and then protected in
+a well stoppered bottle, or better still connected directly to the
+burette.
+
+4. A 10 per cent. solution of barium chloride. Preparation: 100 grams of
+barium chloride are dissolved in one liter of distilled water and
+filtered. The neutrality of the solution should be proven as it must be
+neutral.
+
+5. [Greek: alpha] naptholphthalein indicator according to Sorenson.
+Preparation: 0.1 gram of [Greek: alpha] naphtholphthalein is dissolved in
+150 cubic centimeters of alcohol and 100 cubic centimeters of water.
+For every 10 cubic centimeters of liquid use at least 12 drops of
+indicator.
+
+6. Phenolphthalein solution 1 gram to 100 cubic centimeter 96 per cent.
+alcohol.
+
+7. Solvent, 50 per cent. alcohol neutralized.
+
+
+MANIPULATION.
+
+First--Determine the strength of the N/10 alcoholic sodium hydroxide in
+terms of N/10 hydrochloric acid and calculate the factor, e. g.:
+
+    10 c.c. N/10 alcoholic NaOH = 9.95 N/10 HCl}
+    10 c.c. N/10 alcoholic NaOH = 9.96 N/10 HCl} 9.96
+
+The alcoholic N/10 NaOH has a factor of 0.996.
+
+Second--Control the N/40 stearic acid with the above alkali to obtain
+its factor, e. g.:
+
+    40 c.c. N/40 alcoholic stearic acid =
+                              10.18 c.c. N/10 NaOH }
+    40 c.c. N/40 alcoholic stearic acid =          } 10.2
+                              10.22 c.c. N/10 NaOH }
+
+    10.2 x F N/10 NaOH (0.996) = Factor N/40 stearic acid
+
+        Therefore Factor N/40 stearic acid = 1.016.
+
+Third--About 5 grams of soap are weighed and dissolved in 100 cubic
+centimeters of 50 per cent. neutralized alcohol in a 250 cubic
+centimeter Erlenmeyer flask over a water bath and connected with a
+reflux condensor. When completely dissolved, which takes but a few
+moments, it is cooled by allowing a stream of running water to run over
+the outside of the flask.
+
+Fourth--The soap is precipitated with 15 to 20 cubic centimeters of the
+10 per cent. barium chloride solution.
+
+Fifth--After the addition of 2 to 5 cubic centimeters of [Greek: alpha]
+naphtholphthalein solution the solution is titrated with N/40 alcoholic
+stearic acid. [Greek: alpha] naphtholphthalein is red with an excess of
+stearic acid. To mark the color changes it is advisable to first run a
+few blanks until the eye has become accustomed to the change in the
+indicator in the same way. The change from green to red can then be
+carefully observed.
+
+Let us presume 5 grams of soap were taken for the analysis and 20 cubic
+centimeters of N/40 stearic acid were required for the titration then to
+calculate the amount of NaOH since the stearic factor is 1.016.
+
+20 x 1.016 = 20.32 N/40 stearic acid really required.
+
+1 cubic centimeter N/40 stearic acid = 0.02 per cent. NaOH for 5 grams
+soap.
+
+[Greek: Delta] 20.32 cubic centimeters N/40 stearic acid = 0.02 x 20.32
+per cent. NaOH for 5 grams soap.
+
+Hence the soap contains 0.4064 per cent. NaOH.
+
+It is necessary, however, to make a correction by this method. When the
+free alkali amounts to over 0.1 per cent. the correction is + 0.01, and
+when the free alkali exceeds 0.4 per cent. the correction is + 0.04,
+hence in the above case we multiply 0.004064 by 0.04, add this amount to
+0.004064 and multiply by 100 to obtain the true percentage. Should the
+alkalinity have been near 0.1 per cent. we would have multiplied by 0.01
+and added this.
+
+If carbonate is also present in the soap, another 5 grams of soap is
+dissolved in 100 cubic centimeters of 50 per cent. alcohol and the
+solution titrated directly after cooling with N/40 stearic acid, using
+[Greek: alpha] naphtholphthalein or phenolphthalein as an indicator,
+without the addition of barium chloride. From the difference of the two
+titrations the alkali present as carbonate is determined.
+
+If the decomposed soap solution is colorless with phenolphthalein, free
+fatty acids are present, which may be quickly determined with alcoholic
+N/10 sodium hydroxide.
+
+
+INSOLUBLE MATTER.
+
+The insoluble matter in soap may consist of organic or inorganic
+substances. Among the organic substances which are usually present in
+soap are oat meal, bran, sawdust, etc., while among the common inorganic
+or mineral compounds are pumice, silex, clay, talc, zinc oxide,
+infusorial earth, sand or other material used as fillers.
+
+To determine insoluble matter, 5 grams of soap are dissolved in 75 cubic
+centimeters of hot water. The solution is filtered through a weighed
+gooch crucible or filter paper. The residue remaining on the filter is
+washed with hot water until all the soap is removed, is then dried to
+constant weight at 105 degrees C. and weighed. From the difference in
+weight of the gooch or filter paper and the dried residue remaining
+thereon after filtering and drying, the total percentage of insoluble
+matter may easily be calculated. By igniting the residue and reweighing
+the amount of insoluble mineral matter can be readily determined.
+
+
+STARCH AND GELATINE.
+
+Should starch or gelatine be present in soap it is necessary to extract
+5 grams of the soap with 100 cubic centimeters of 95 per cent.
+neutralized alcohol in a Soxhlet extractor until the residue on the
+extraction thimble is in a powder form. If necessary the apparatus
+should be disconnected and any lumps crushed, as these may contain soap.
+The residue remaining on the thimble consists of all substances present
+in soap, insoluble in alcohol. This is dried and weighed so that any
+percentage of impurities not actually determined can be found by
+difference. Starch and gelatine are separated from carbonate, sulfate
+and borate by dissolving the latter out through a filter with cold
+water. The starch and gelatine thus remaining can be determined by
+known methods, starch by the method of direct hydrolysis[15] and
+gelatine by Kjeldahling and calculating the corresponding amount of
+gelatine from the percentage of nitrogen (17.9%) therein.[16]
+
+
+TOTAL FATTY AND RESIN ACIDS.
+
+To the filtrate from the insoluble matter add 40 cubic centimeters of
+half normal sulfuric acid, all the acid being added at once. Boil, stir
+thoroughly for some minutes and keep warm on a water bath until the
+fatty acids have collected as a clear layer on the surface. Cool by
+placing the beaker in ice and syphon off the acid water through a
+filter. Should the fatty acids not readily congeal a weighed amount of
+dried bleached bees-wax or stearic acid may be added to the hot mixture.
+This fuses with the hot mass and forms a firm cake of fatty acids upon
+cooling. Without removing the fatty acids from the beaker, add about 300
+cubic centimeters of hot water, cool, syphon off the water through the
+same filter used before and wash again. Repeat washing, cooling and
+syphoning processes until the wash water is no longer acid. When this
+stage is reached, dissolve any fatty acid which may have remained on the
+filter with hot 95 per cent. alcohol into the beaker containing the
+fatty acids. Evaporate the alcohol and dry the beaker to constant weight
+over a water bath. The fatty acids thus obtained represent the combined
+fatty acids, uncombined fat and hydrocarbons.
+
+
+DETERMINATION OF ROSIN.
+
+If resin acids are present, this may be determined by the
+Liebermann-Storch reaction. To carry out this test shake 2 cubic
+centimeters of the fatty acids with 5 cubic centimeters of acetic
+anhydride; warm slightly; cool; draw off the anhydride and add 1:1
+sulfuric acid. A violet color, which is not permanent, indicates the
+presence of rosin in the soap. The cholesterol in linseed or fish oil,
+which of course may be present in the soap, also give this reaction.
+
+Should resin acids be present, these may be separated by the Twitchell
+method, which depends upon the difference in the behavior of the fatty
+and resin acids when converted into their ethyl esters through the
+action of hydrochloric acid. This may be carried out as follows:
+
+Three grams of the dried mixed acids are dissolved in 25 cubic
+centimeters of absolute alcohol in a 100 cubic centimeter stoppered
+flask; the flask placed in cold water and shaken. To this cooled
+solution 25 cubic centimeters of absolute alcohol saturated with dry
+hydrochloric acid is added. The flask is shaken occasionally and the
+action allowed to continue for twenty minutes, then 10 grams of dry
+granular zinc chloride are added, the flask shaken and again allowed to
+stand for twenty minutes. The contents of the flask are then poured into
+200 cubic centimeters of water in a 500 cubic centimeter beaker and the
+flask rinsed out with alcohol. A small strip of zinc is placed in the
+beaker and the alcohol evaporated. The beaker is then cooled and
+transferred to a separatory funnel, washing out the beaker with 50 cubic
+centimeters of gasoline (boiling below 80 degrees C.) and extracting by
+shaking the funnel well. Draw off the acid solution after allowing to
+separate and wash the gasoline with water until free from hydrochloric
+acid. Draw off the gasoline solution and evaporate the gasoline.
+Dissolve the residue in neutral alcohol and titrate with standard alkali
+using phenolphthalein as an indicator. One cubic centimeter of normal
+alkali equals 0.346 grams of rosin. The rosin may be gravimetrically
+determined by washing the gasoline extract with water, it not being
+necessary to wash absolutely free from acid, then adding 0.5 gram of
+potassium hydroxide and 5 cubic centimeters of alcohol in 50 cubic
+centimeters of water. Upon shaking the resin acids are rapidly
+saponified and extracted by the dilute alkaline solution as rosin soaps,
+while the ethyl esters remain in solution in the gasoline. Draw off the
+soap solution, wash the gasoline solution again with dilute alkali and
+unite the alkaline solutions. Decompose the alkaline soap solution with
+an excess of hydrochloric acid and weigh the resin acids liberated as in
+the determination of total fatty acids.
+
+According to Lewkowitsch, the results obtained by the volumetric method
+which assumes a combining weight of 346 for resin acids, are very likely
+to be high. On the other hand those obtained by the gravimetric method
+are too low.
+
+Leiste and Stiepel[17] have devised a simpler method for the
+determination of rosin. They make use of the fact that the resin acids
+as sodium soaps are soluble in acetone and particularly acetone
+containing two per cent. water, while the fatty acid soaps are soluble
+in this solvent to the extent of only about 2 per cent. First of all it
+is necessary to show that the sample to be analyzed contains a mixture
+of resin and fatty acids. This may be done by the Liebermann-Storch
+reaction already described. Glycerine interferes with the method. Two
+grams of fatty acids or 3 grams of soap are weighed in a nickel crucible
+and dissolved in 15-20 cubic centimeters of alcohol. The solution is
+then neutralized with alcoholic sodium hydroxide, using phenolphthalein
+as an indicator. The mass is concentrated by heat over an asbestos plate
+until a slight film forms over it. Then about 10 grams of sharp,
+granular, ignited sand are stirred in by means of a spatula, the alcohol
+further evaporated, the mixture being constantly stirred and then
+thoroughly dried in a drying oven. The solvent for the cooled mass is
+acetone containing 2 per cent. water. It is obtained from acetone dried
+by ignited sodium sulfate and adding 2 per cent. water by volume. One
+hundred cubic centimeters of this solvent are sufficient for extracting
+the above. The extraction of the rosin soap is conducted by adding 10
+cubic centimeters of acetone eight times, rubbing the mass thoroughly
+with a spatula and decanting. The decanted portions are combined in a
+beaker and the suspended fatty soaps allowed to separate. The mixture is
+then filtered into a previously weighed flask and washed several times
+with the acetone remaining. The solution of rosin soap should show no
+separation of solid matter after having evaporated to half the volume
+and allowing to cool. If a separation should occur another filtration
+and the slightest possible washing is necessary. To complete the
+analysis, the acetone is completely evaporated and the mass dried to
+constant weight in a drying oven. The weight found gives the weight of
+the rosin soap. In conducting the determination, it is important to dry
+the mixture of soap and sand thoroughly. In dealing with potash soaps it
+is necessary to separate the fatty acids from these and use them as
+acetone dissolves too great a quantity of a potash soap.
+
+
+TOTAL ALKALI.
+
+In the filtrate remaining after having washed the fatty acids in the
+determination of total fatty and resin acids all the alkali present as
+soap, as carbonate and as hydroxide remains in solution as sulfate. Upon
+titrating this solution with half normal alkali the difference between
+the half normal acid used in decomposing the soap and alkali used in
+titrating the excess of acid gives the amount of total alkali in the
+soap. By deducting the amount of free alkali present as carbonate or
+hydroxide previously found the amount of combined alkali in the soap may
+be calculated.
+
+To quickly determine total alkali in soap a weighed portion of the soap
+may be ignited to a white ash and the ash titrated for alkalinity using
+methyl orange as an indicator.
+
+
+UNSAPONIFIED MATTER.
+
+Dissolve 5 grams of soap in 50 cubic centimeters of 50 per cent.
+alcohol. Should any free fatty acids be present neutralize them with
+standard alkali. Wash into a separatory funnel with 50 per cent. alcohol
+and extract with 100 cubic centimeters of gasoline, boiling at 50
+degrees to 60 degrees C. Wash the gasoline with water, draw off the
+watery layer. Run the gasoline into a weighed dish, evaporate the
+alcohol, dry and weigh the residue as unsaponified matter. The residue
+contains any hydrocarbon oils or fats not converted into soap.
+
+
+SILICA AND SILICATES.
+
+The insoluble silicates, sand, etc., are present in the ignited residue
+in the determination of insoluble matter. Sodium silicate, extensively
+used as a filler, however, will only show itself in forming a pasty
+liquid. Where it is desired to determine sodium silicate, 10 grams of
+soap are ashed by ignition, hydrochloric acid added to the ash in excess
+and evaporated to dryness. More hydrochloric acid is then added and the
+mass is again evaporated until dry; then cooled; moistened with
+hydrochloric acid; dissolved in water; filtered; washed; the filtrate
+evaporated to dryness and again taken up with hydrochloric acid and
+water; filtered and washed. The precipitates are then combined and
+ignited. Silicon dioxide (SiO_{2}) is thus formed, which can be
+calculated to sodium silicate (Na_{2}Si_{4}O_{9}). Should other metals
+than alkali metals be suspected present the filtrate from the silica
+determinations should be examined.
+
+
+GLYCERINE IN SOAP.
+
+To determine the amount of glycerine contained in soap dissolve 25 grams
+in hot water, add a slight excess of sulfuric acid and keep hot until
+the fatty acids form as a clear layer on top. Cool the mass and remove
+the fatty acids. Filter the acid solution into a 25 cubic centimeter
+graduated flask; bring to the mark with water and determine the
+glycerine by the bichromate method as described under glycerine
+analysis.
+
+When sugar is present the bichromate would be reduced by the sugar,
+hence this method is not applicable. In this case remove the fatty acids
+as before, neutralize an aliquot portion with milk of lime, evaporate to
+10 cubic centimeters, add 2 grams of sand and milk of lime containing
+about 2 grams of calcium hydroxide and evaporate almost to dryness.
+Treat the moist residue with 5 cubic centimeters of 96 per cent.
+alcohol, rub the whole mass into a paste, then constantly stirring, heat
+on a water bath and decant into a 250 cubic centimeter graduated flask.
+Repeat the washing with 5 cubic centimeters of alcohol five or six
+times, each time pouring the washings into the flask; cool the flask to
+room temperature and fill to the mark with 96 per cent. alcohol, agitate
+the flask until well mixed and filter through a dry filter paper. Take
+200 cubic centimeters of the nitrate and evaporate to a syrupy
+consistency over a safety water bath. Wash the liquor into a stoppered
+flask with 20 cubic centimeters of absolute alcohol, add 30 cubic
+centimeters of absolute ether 10 cubic centimeters at a time, shaking
+well after each addition and let stand until clear. Pour off the
+solution through a filter into a weighed dish and wash out the flask
+with a mixture of three parts absolute ether and two parts absolute
+alcohol. Evaporate to a syrup, dry for one hour at the temperature of
+boiling water, weigh, ignite and weigh again. The loss is glycerine.
+This multiplied by 5/4 gives the total loss for the aliquot portion
+taken. The glycerine may also be determined by the acetin or bichromate
+methods after driving off the alcohol and ether if so desired.
+
+
+SUGAR IN SOAP.
+
+To determine sugar in soap, usually present in transparent soaps,
+decompose a soap solution of 5 grams of soap dissolved in 100 cubic
+centimeters of hot water with an excess of hydrochloric acid and
+separate the fatty acids as usual. Filter the acid solution into a
+graduated flask and make up to the mark. Take an aliquot containing
+approximately 1 per cent. of reducing sugar and determine the amount of
+sugar by the Soxhlet method.[18]
+
+
+GLYCERINE ANALYSIS.
+
+The methods of analyzing glycerine varied so greatly due to the fact
+that glycerine contained impurities which acted so much like glycerine
+as to introduce serious errors in the determinations of crude glycerine.
+This led to the appointment of committees in the United States and
+Europe to investigate the methods of glycerine analysis. An
+international committee met after their investigations and decided the
+acetin method should control the buying and selling of glycerine, but
+the more convenient bichromate method in a standardized form might be
+used in factory control and other technical purposes. The following are
+the methods of analysis and sampling as suggested by the international
+committee:
+
+
+SAMPLING.
+
+The most satisfactory method available for sampling crude glycerine
+liable to contain suspended matter, or which is liable to deposit salt
+on settling, is to have the glycerine sampled by a mutually approved
+sampler as soon as possible after it is filled into drums, but in any
+case before any separation of salt has taken place. In such cases he
+shall sample with a sectional sampler (see appendix) then seal the
+drums, brand them with a number for identification, and keep a record of
+the brand number. The presence of any visible salt or other suspended
+matter is to be noted by the sampler, and a report of the same made in
+his certificate, together with the temperature of the glycerine. Each
+drum must be sampled. Glycerine which has deposited salt or other solid
+matter cannot be accurately sampled from the drums, but an approximate
+sample can be obtained by means of the sectional sampler, which will
+allow a complete vertical section of the glycerine to be taken including
+any deposit.
+
+
+ANALYSIS.
+
+1. _Determination of Free Caustic Alkali._--Put 20 grams of the sample
+into a 100 cc. flask, dilute with approximately 50 cc. of freshly boiled
+distilled water, add an excess of neutral barium chloride solution, 1
+cc. of phenolphthalein solution, make up to the mark and mix. Allow the
+precipitate to settle, draw off 50 cc. of the clear liquid and titrate
+with normal acid (_N_/1). Calculate the percentage of Na_{2}O existing
+as caustic alkali.
+
+2. _Determination of Ash and Total Alkalinity._--Weigh 2 to 5 grams of
+the sample in a platinum dish, burn off the glycerine over a luminous
+Argand burner or other source of heat,[19] giving a low temperature, to
+avoid volatilization and the formation of sulphides. When the mass is
+charred to the point that water will not be colored by soluble organic
+matter, lixiviate with hot distilled water, filter, wash and ignite the
+residue in the platinum dish. Return the filtrate and washings to the
+dish, evaporate the water, and carefully ignite without fusion. Weigh
+the ash.
+
+Dissolve the ash in distilled water and titrate total alkalinity, using
+as indicator methyl orange cold or litmus boiling.
+
+3. _Determination of Alkali Present as Carbonate._--Take 10 grams of the
+sample, dilute with 50 cc. distilled water, add sufficient _N_/1 acid to
+neutralize the total alkali found at (2), boil under a reflux condenser
+for 15 to 20 minutes, wash down the condenser tube with distilled water,
+free from carbon dioxide, and then titrate back with _N_/1 NaOH, using
+phenolphthalein as indicator. Calculate the percentage of Na_{2}O.
+Deduct the Na_{2}O found in (1). The difference is the percentage of
+Na_{2}O existing as carbonate.
+
+4. _Alkali Combined with Organic Acids._--The sum of the percentages of
+Na_{2}O found at (1) and (3) deducted from the percentage found at (2)
+is a measure of the Na_{2}O or other alkali combined with organic acids.
+
+5. _Determination of Acidity._--Take 10 grams of the sample, dilute with
+50 cc. distilled water free from carbon dioxide, and titrate with _N_/1
+NaOH and phenolphthalein. Express in terms of Na_{2}O required to
+neutralize 100 grams.
+
+6. _Determination of Total Residue at 160deg. C._--For this determination
+the crude glycerine should be slightly alkaline with Na_{2}CO_{3} not
+exceeding 0.2 per cent. Na_{2}O, in order to prevent loss of organic
+acids. To avoid the formation of polyglycerols this alkalinity must not
+be exceeded.
+
+Ten grams of the sample are put into a 100 cc. flask, diluted with water
+and the calculated quantity of _N_/1 HCl or Na_{2}CO_{3} added to give
+the required degree of alkalinity. The flask is filled to 100 cc., the
+contents mixed, and 10 cc. measured into a weighed Petrie or similar
+dish 2.5 in. in diameter and 0.5 in. deep, which should have a flat
+bottom. In the case of crude glycerine abnormally high in organic
+residue a smaller amount should be taken, so that the weight of the
+organic residue does not materially exceed 30 to 40 milligrams.
+
+The dish is placed on a water bath (the top of the 160deg. oven acts
+equally well) until most of the water has evaporated. From this point
+the evaporation is effected in the oven. Satisfactory results are
+obtained in an oven[20] measuring 12 ins. cube, having an iron plate
+0.75 in. thick lying on the bottom to distribute the heat. Strips of
+asbestos millboard are placed on a shelf half way up the oven. On these
+strips the dish containing the glycerine is placed.
+
+If the temperature of the oven has been adjusted to 160deg. C. with the
+door closed, a temperature of 130deg. to 140deg. can be readily maintained
+with the door partially open, and the glycerine, or most of it, should
+be evaporated off at this temperature. When only a slight vapor is seen
+to come off, the dish is removed and allowed to cool.
+
+An addition of 0.5 to 1.0 cc. of water is made, and by a rotary motion
+the residue brought wholly or nearly into solution. The dish is then
+allowed to remain on a water bath or top of the oven until the excess
+water has evaporated and the residue is in such a condition that on
+returning to the oven at 160deg. C. it will not spurt. The time taken up to
+this point cannot be given definitely, nor is it important. Usually two
+or three hours are required. From this point, however, the schedule of
+time must be strictly adhered to. The dish is allowed to remain in the
+oven, the temperature of which is carefully maintained at 160deg. C. for
+one hour, when it is removed, cooled, the residue treated with water,
+and the water evaporated as before. The residue is then subjected to a
+second baking of one hour, after which the dish is allowed to cool in a
+desiccator over sulphuric acid and weighed. The treatment with water,
+etc., is repeated until a constant loss of 1 to 1.5 mg. per hour is
+obtained.
+
+In the case of acid glycerine a correction must be made for the alkali
+added 1 cc. _N_/1 alkali represents an addition of 0.03 gram. In the
+case of alkaline crudes a correction should be made for the acid added.
+Deduct the increase in weight due to the conversion of the NaOH and
+Na_{2}CO_{3} to NaCl. The corrected weight multiplied by 100 gives the
+percentage of _total residue at 160deg. C._
+
+This residue is taken for the determination of the non-volatile
+acetylizable impurities (see acetin method).
+
+7. _Organic residue._--Subtract the ash from the total residue at 160deg.
+C. Report as organic residue at 160deg. C. (it should be noted that
+alkaline salts of fatty acids are converted to carbonates on ignition
+and that the CO_{3} thus derived is not included in the organic
+residue).
+
+
+ACETIN PROCESS FOR THE DETERMINATION OF GLYCEROL.
+
+This process is the one agreed upon at a conference of delegates from
+the British, French, German and American committees, and has been
+confirmed by each of the above committees as giving results nearer to
+the truth than the bichromate method on crudes in general. It is the
+process to be used (if applicable) whenever only one method is employed.
+On pure glycerines the results are identical with those obtained by the
+bichromate process. For the application of this method the crude
+glycerine should not contain over 60 per cent. water.
+
+
+REAGENTS REQUIRED.
+
+(_A_) _Best Acetic Anhydride._--This should be carefully selected. A
+good sample must not require more than 0.1 cc. normal NaOH for
+saponification of the impurities when a blank is run on 7.5 cc. Only a
+slight color should develop during digestion of the blank.
+
+The anhydride may be tested for strength by the following method: Into a
+weighed stoppered vessel, containing 10 to 20 cc. of water, run about 2
+cc. of the anhydride, replace the stopper and weigh. Let stand with
+occasional shaking, for several hours, to permit the hydrolysis of all
+the anhydride; then dilute to about 200 cc., add phenolphthalein and
+titrate with _N_/1 NaOH. This gives the total acidity due to free acetic
+acid and acid formed from the anhydride. It is worthy of note that in
+the presence of much free anhydride a compound is formed with
+phenolphthalein, soluble in alkali and acetic acid, but insoluble in
+neutral solutions. If a turbidity is noticed toward the end of the
+neutralization it is an indication that the anhydride is incompletely
+hydrolyzed and inasmuch as the indicator is withdrawn from the solution,
+results may be incorrect.
+
+Into a stoppered weighing bottle containing a known weight of recently
+distilled aniline (from 10 to 20 cc.) measure about 2 cc. of the sample,
+stopper, mix, cool and weigh. Wash the contents into about 200 cc. of
+cold water, and titrate the acidity as before. This yields the acidity
+due to the original, preformed, acetic acid plus one-half the acid due
+to anhydride (the other half having formed acetanilide); subtract the
+second result from the first (both calculated to 100 grams) and double
+the result, obtaining the cc. _N_/1 NaOH per 100 grams of the sample. 1
+cc. _N_/NaOH equals 0.0510 anhydride.
+
+(_B_) _Pure Fused Sodium Acetate._--The purchased salt is again
+completely fused in a platinum, silica or nickel dish, avoiding
+charring, powdered quickly and kept in a stoppered bottle or desiccator.
+It is most important that the sodium acetate be anhydrous.
+
+(_C_) _A Solution of Caustic Soda for Neutralizing, of about N_/1
+_Strength, Free from Carbonate._--This can be readily made by dissolving
+pure sodium hydroxide in its own weight of water (preferably water free
+from carbon dioxide) and allowing to settle until clear, or filtering
+through an asbestos or paper filter. The clear solution is diluted with
+water free from carbon dioxide to the strength required.
+
+(_D_) _N_/1 _Caustic Soda Free from Carbonate._--Prepared as above and
+carefully standardized. Some caustic soda solutions show a marked
+diminution in strength after being boiled; such solutions should be
+rejected.
+
+(_E_) _N_/1 _Acid._--Carefully standardized.
+
+(_F_) _Phenolphthalein Solution._--0.5 per cent. phenolphthalein in
+alcohol and neutralized.
+
+
+THE METHOD.
+
+In a narrow-mouthed flask (preferably round-bottomed), capacity about
+120 cc., which has been thoroughly cleaned and dried, weigh accurately
+and as rapidly as possible 1.25 to 1.5 grams of the glycerine. A Grethan
+or Lunge pipette will be found convenient. Add about 3 grams of the
+anhydrous sodium acetate, then 7.5 cc. of the acetic anhydride, and
+connect the flask with an upright Liebig condenser. For convenience the
+inner tube of this condenser should not be over 50 cm. long and 9 to 10
+mm. inside diameter. The flask is connected to the condenser by either a
+ground glass joint (preferably) or a rubber stopper. If a rubber stopper
+is used it should have had a preliminary treatment with hot acetic
+anhydride vapor.
+
+Heat the contents and keep just boiling for one hour, taking precautions
+to prevent the salts drying on the sides of the flask.
+
+Allow the flask to cool somewhat, and through the condenser tube add 50
+cc. of distilled water free from carbon dioxide at a temperature of
+about 80deg. C., taking care that the flask is not loosened from the
+condenser. The object of cooling is to avoid any sudden rush of vapors
+from the flask on adding water, and to avoid breaking the flask. Time is
+saved by adding the water before the contents of the flask solidify, but
+the contents may be allowed to solidify and the test proceeded with the
+next day without detriment, bearing in mind that the anhydride in excess
+is much more effectively hydrolyzed in hot than in cold water. The
+contents of the flask may be warmed to, but must not exceed, 80deg. C.,
+until the solution is complete, except a few dark flocks representing
+organic impurities in the crude. By giving the flask a rotary motion,
+solution is more quickly effected.
+
+Cool the flask and contents without loosening from the condenser. When
+quite cold wash down the inside of the condenser tube, detach the flask,
+wash off the stopper or ground glass connection into the flask, and
+filter the contents through an acid-washed filter into a Jena glass
+flask of about 1 litre capacity. Wash thoroughly with cold distilled
+water free from carbon dioxide. Add 2 cc. of phenolphthalein solution
+(_F_), then run in caustic soda solution (_C_) or (_D_) until a faint
+pinkish yellow color appears throughout the solution. This
+neutralization must be done most carefully; the alkali should be run
+down the sides of the flask, the contents of which are kept rapidly
+swirling with occasional agitation or change of motion until the
+solution is nearly neutralized, as indicated by the slower disappearance
+of the color developed locally by the alkali running into the mixture.
+When this point is reached the sides of the flask are washed down with
+carbon dioxide-free water and the alkali subsequently added drop by
+drop, mixing after each drop until the desired tint is obtained.
+
+Now run in from a burette 50 cc. or a calculated excess of _N_/1 NaOH
+(_D_) and note carefully the exact amount. Boil gently for 15 minutes,
+the flask being fitted with a glass tube acting as a partial condenser.
+Cool as quickly as possible and titrate the excess of NaOH with _N_/1
+acid (_E_) until the pinkish yellow or chosen end-point color just
+remains.[21] A further addition of the indicator at this point will
+cause an increase of the pink color; this must be neglected, and the
+first end-point taken.
+
+From the _N_/1 NaOH consumed calculate the percentage of glycerol
+(including acetylizable impurities) after making the correction for the
+blank test described below.
+
+1 cc. _N_/1 NaOH = 0.03069 gram glycerol.
+
+The coefficient of expansion for normal solutions is 0.00033 per cc.
+for each degree centigrade. A correction should be made on this account
+if necessary.
+
+_Blank Test._--As the acetic anhydride and sodium acetate may contain
+impurities which affect the result, it is necessary to make a blank
+test, using the same quantities of acetic anhydride, sodium acetate and
+water as in the analysis. It is not necessary to filter the solution of
+the melt in this case, but sufficient time must be allowed for the
+hydrolysis of the anhydride before proceeding with the neutralization.
+After neutralization it is not necessary to add more than 10 cc. of the
+_N_/1 alkali (_D_), as this represents the excess usually present after
+the saponification of the average soap lye crude. In determining the
+acid equivalent of the _N_/1 NaOH, however, the entire amount taken in
+the analysis, 50 cc., should be titrated after dilution with 300 cc.
+water free from carbon dioxide and without boiling.
+
+_Determination of the Glycerol Value of the Acetylizable
+Impurities._--The total residue at 160deg. C. is dissolved in 1 or 2 cc. of
+water, washed into the acetylizing flask and evaporated to dryness. Then
+add anhydrous sodium acetate and acetic anhydride in the usual amounts
+and proceed as described in the regular analysis. After correcting for
+the blank, calculate the result to glycerol.
+
+
+WAYS OF CALCULATING ACTUAL GLYCEROL CONTENT.
+
+(1) Determine the apparent percentage of glycerol in the sample by the
+acetin process as described. The result will include acetylizable
+impurities if any are present.
+
+(2) Determine the total residue at 160deg. C.
+
+(3) Determine the acetin value of the residue at (2) in terms of
+glycerol.
+
+(4) Deduct the result found at (3) from the percentage obtained at (1)
+and report this corrected figure as glycerol. If volatile acetylizable
+impurities are present these are included in this figure.
+
+Trimethyleneglycol is more volatile than glycerine and can therefore be
+concentrated by fractional distillation. An approximation to the
+quantity can be obtained from the spread between the acetin and
+bichromate results on such distillates. The spread multiplied by 1.736
+will give the glycol.
+
+
+BICHROMATE PROCESS FOR GLYCEROL DETERMINATION. REAGENTS REQUIRED.
+
+(_A_) _Pure potassium bichromate_ powdered and dried in air free from
+dust or organic vapors, at 110deg. to 120deg. C. This is taken as the
+standard.
+
+(_B_) _Dilute Bichromate Solution._--7.4564 grams of the above
+bichromate are dissolved in distilled water and the solution made up to
+one liter at 15.5deg. C.
+
+(_C_) _Ferrous Ammonium Sulphate._--It is never safe to assume this salt
+to be constant in composition and it must be standardized against the
+bichromate as follows: dissolve 3.7282 grams of bichromate (_A_) in 50
+cc. of water. Add 50 cc. of 50 per cent. sulphuric acid (by volume), and
+to the cold undiluted solution add from a weighing bottle a moderate
+excess of the ferrous ammonium sulphate, and titrate back with the
+dilute bichromate (_B_). Calculate the value of the ferrous salt in
+terms of bichromate.
+
+(_D_) _Silver Carbonate._--This is prepared as required for each test
+from 140 cc. of 0.5 per cent. silver sulphate solution by precipitation,
+with about 4.9 cc. _N_/1 sodium carbonate solution (a little less than
+the calculated quantity of _N_/1 sodium carbonate should be used as an
+excess to prevent rapid settling). Settle, decant and wash one by
+decantation.
+
+(_E_) _Subacetate of Lead._--Boil a 10 per cent. solution of pure lead
+acetate with an excess of litharge for one hour, keeping the volume
+constant, and filter while hot. Disregard any precipitate which
+subsequently forms. Preserve out of contact with carbon dioxide.
+
+(_F_) _Potassium Ferricyanide._--A very dilute, freshly prepared
+solution containing about 0.1 per cent.
+
+
+THE METHOD.
+
+Weigh 20 grams of the glycerine, dilute to 250 cc. and take 25 cc. Add
+the silver carbonate, allow to stand, with occasional agitation, for
+about 10 minutes, and add a slight excess (about 5 cc. in most cases) of
+the basic lead acetate (_E_), allow to stand a few minutes, dilute with
+distilled water to 100 cc., and then add 0.15 cc. to compensate for the
+volume of the precipitate, mix thoroughly, filter through an air-dry
+filter into a suitable narrow-mouthed vessel, rejecting the first 10
+cc., and return the filtrate if not clear and bright. Test a portion of
+the filtrate with a little basic lead acetate, which should produce no
+further precipitate (in the great majority of cases 5 cc. are ample, but
+occasionally a crude will be found requiring more, and in this case
+another aliquot of 25 cc. of the dilute glycerine should be taken and
+purified with 6 cc. of the basic acetate). Care must be taken to avoid a
+marked excess of basic acetate.
+
+Measure off 25 cc. of the clear filtrate into a flask or beaker
+(previously cleaned with potassium bichromate and sulphuric acid). Add
+12 drops of sulphuric acid (1: 4) to precipitate the small excess of
+lead as sulphate. Add 3.7282 grams of the powdered potassium bichromate
+(_A_). Rinse down the bichromate with 25 cc. of water and let stand with
+occasional shaking until all the bichromate is dissolved (no reduction
+will take place in the cold).
+
+Now add 50 cc. of 50 per cent. sulphuric acid (by volume) and immerse
+the vessel in boiling water for two hours and keep protected from dust
+and organic vapors, such as alcohol, till the titration is completed.
+Add from a weighing bottle a slight excess of the ferrous ammonium
+sulphate (_C_), making spot tests on a porcelain plate with the
+potassium ferricyanide (_F_). Titrate back with the dilute bichromate.
+From the amount of bichromate reduced calculate the percentage of
+glycerol.
+
+1 gram glycerol = 7.4564 grams bichromate.
+
+1 gram bichromate = 0.13411 gram glycerol.
+
+The percentage of glycerol obtained above includes any oxidizable
+impurities present after the purification. A correction for the
+non-volatile impurities may be made by running a bichromate test on the
+residue at 160deg. C.
+
+
+NOTES.
+
+(1) It is important that the concentration of acid in the oxidation
+mixture and the time of oxidation should be strictly adhered to.
+
+(2) Before the bichromate is added to the glycerine solution it is
+essential that the slight excess of lead be precipitated with sulphuric
+acid, as stipulated.
+
+(3) For crudes practically free from chlorides the quantity of silver
+carbonate may be reduced to one-fifth and the basic lead acetate to 0.5
+cc.
+
+(4) It is sometimes advisable to add a little potassium sulphate to
+insure a clear filtrate.
+
+
+SAMPLING CRUDE GLYCERINE.
+
+The usual method of sampling crude glycerine hitherto has been by means
+of a glass tube, which is slowly lowered into the drum with the object
+of taking as nearly as possible a vertical section of the glycerine
+contained in the drum. This method has been found unsatisfactory, owing
+to the fact that in cold climates glycerine runs into the tube very
+slowly, so that, owing to the time occupied, it is impossible to take a
+complete section of the crude. Another objection to the glass tube is
+that it fails to take anything approaching a correct proportion of any
+settled salt contained in the drum.
+
+The sampler which is illustrated herewith has been devised with the
+object of overcoming the objections to the glass tube as far as
+possible. It consists of two brass tubes, one fitting closely inside the
+other. A number of ports are cut out in each tube in such a way that
+when the ports are opened a continuous slot is formed which enables a
+complete section to be taken throughout the entire length of the drum.
+By this arrangement the glycerine fills into the sampler almost
+instantaneously. There are a number of ports cut at the bottom of the
+sampler which render it possible to take a proportion of the salt at the
+bottom of the drum. The instrument is so constructed that all the ports,
+including the bottom ones, can be closed simultaneously by the simple
+action of turning the handle at the top; a pointer is arranged which
+indicates on a dial when the sampler is open or closed. In samplers of
+larger section (1 in.) it is possible to arrange a third motion whereby
+the bottom ports only are open for emptying, but in samplers of smaller
+dimensions (5/8 in.) this third motion must be dispensed with, otherwise
+the dimensions of the ports have to be so small that the sampler would
+not be efficient.
+
+In using the sampler it is introduced into the drum with the ports
+closed, and when it has touched the bottom, the ports are opened for a
+second or two, then closed and withdrawn, and the sample discharged into
+the receiving vessel by opening the ports. When the drum contains salt
+which has deposited, the ports must be opened before the sampler is
+pushed through the salt, thus enabling a portion to be included in the
+sample. It is, however, almost impossible to obtain a correct proportion
+of salt after it has settled in the drum and it is therefore recommended
+that the drum be sampled before any salt has deposited. A sampler 1 in.
+in diameter withdraws approximately 10 oz. from a 110-gal. drum. A
+sampler 5/8 in. in diameter will withdraw about 5 oz.
+
+FOOTNOTES:
+
+[13] Zeit. Angew. Chem. 19, 385 (1906).
+
+[14] Zeit. Angew. Chem. 27, 11-20 (1914).
+
+[15] Bull. 107, Bur. Chem. U. S. Dept. Agriculture.
+
+[16] Richards and Gies, Am. J. Physiol. (1902) 7, 129.
+
+[17] Seifensieder Ztg. (1913) No. 46.
+
+[18] Bull 107, Bur. Chem. U. S. Dept. Agriculture.
+
+[19] Carbon is readily burned off completely, without loss of chlorides,
+in a gas-heated muffle furnace adjusted to a dull red heat.
+
+[20] An electric oven suitable for this work, which is readily adjusted
+to 160 degs. C., has been made for Mr. Low and the chairman, by the
+Apparatus and Specialty Company, Lansing, Mich. Its size is 9-1/2 x 10 x
+16 inches, and capacity 8 Petrie dishes. It gives a strong draft at
+constant temperature.
+
+[21] A precipitate at this point is an indication of the presence of
+iron or alumina, and high results will be obtained unless a correction
+is made as described below.
+
+
+
+
+CHAPTER VII
+
+Standard Methods for the Sampling and Analysis of Commercial Fats and
+Oils[22]
+
+
+The following report of the _Committee on Analysis of Commercial Fats
+and Oils_ of the _Division of Industrial Chemists and Chemical
+Engineers_ of the American Chemical Society was adopted April 14, 1919,
+by unanimous vote:
+
+W. D. RICHARDSON, _Chairman_,
+Swift and Co., Chicago, Ill.
+
+R. W. BAILEY,
+Stillwell and Gladding, New York City.
+
+W. J. GASCOYNE,
+W. J. Gascoyne and Co., Baltimore, Md.
+
+I. KATZ,[A]
+Wilson and Co., Chicago, Ill.
+
+A. LOWENSTEIN,[A]
+Morris and Co., Chicago, Ill.
+
+H. J. MORRISON,
+Proctor and Gamble Co.,
+Ivorydale, Ohio.
+
+J. R. POWELL,
+Armour Soap Works, Chicago, Ill.
+
+R. J. QUINN,[A]
+Midland Chemical Co., Argo, Ill.
+
+PAUL RUDNICK,
+Armour and Co., Chicago, Ill.
+
+L. M. TOLMAN,
+Wilson and Co., Chicago, Ill.
+
+E. TWITCHELL,[A]
+Emery Candle Co., Cincinnati, Ohio.
+
+J. J. VOLLERTSEN,
+Morris and Co., Chicago, Ill.
+
+[Note A: Resigned.]
+
+
+Scope, Applicability and Limitations of the Methods.
+
+
+SCOPE.
+
+These methods are intended to aid in determining the commercial
+valuation of fats and fatty oils in their purchase and sale, based on
+the fundamental assumption commonly recognized in the trade, namely,
+that the product is true to name and is not adulterated. For methods for
+determining the identity of oils and fats, the absence of adulterants
+therein and for specific tests used in particular industries, the
+chemist is referred to standard works on the analysis of fats and oils.
+
+
+APPLICABILITY.
+
+The methods are applicable in commercial transactions involving fats and
+fatty oils used in the soap, candle and tanning industries, to edible
+fats and oils and to fats and fatty oils intended for lubricating and
+burning purposes. The methods are applicable to the raw oils used in the
+varnish and paint industry with the exceptions noted under limitations,
+but special methods have not been included.
+
+
+LIMITATIONS.
+
+The methods have not been developed with special reference to waxes
+(beeswax, carnauba wax, wool wax, etc.) although some of them may be
+found applicable to these substances. The Committee considers the Wijs
+method superior to the Hanus method for the determination of iodine
+number of linseed oil as well as other oils, although the Hanus method
+has been considered standard for this work for some time and has been
+adopted by the American Society for Testing Materials and in various
+specifications. It has been customary to use the Huebl method for the
+determination of iodine value of tung oil (China wood oil) but the
+Committee's work indicates that the Wijs method is satisfactory for this
+determination.
+
+
+Sampling.
+
+
+TANK CARS.
+
+1. SAMPLING WHILE LOADING--Sample shall be taken at discharge of pipe
+where it enters tank car dome. The total sample taken shall be not less
+than 50 lbs. and shall be a composite of small samples of about 1 pound
+each, taken at regular intervals during the entire period of loading.
+
+The sample thus obtained is thoroughly mixed and uniform 3-lb. portions
+placed in air-tight 3-lb. metal containers. At least three such samples
+shall be put up, one for the buyer, one for the seller, and the third to
+be sent to a referee chemist in case of dispute. All samples are to be
+promptly and correctly labeled and sealed.
+
+2. SAMPLING FROM CAR ON TRACK[23]--(_a_) _When contents are solid._[24]
+In this case the sample is taken by means of a large tryer measuring
+about 2 in. across and about 1-1/2 times the depth of the car in length.
+Several tryerfuls are taken vertically and obliquely toward the ends of
+the car until 50 lbs. are accumulated, when the sample is softened,
+mixed and handled as under (1). In case the contents of the tank car
+have assumed a very hard condition, as in Winter weather, so that it is
+impossible to insert the tryer, and it becomes necessary to soften the
+contents of the car by means of the closed steam coil (in nearly all
+tank cars the closed steam coil leaks) or by means of open steam in
+order to draw a proper sample, suitable arrangements must be made
+between buyer and seller for the sampling of the car after it is
+sufficiently softened, due consideration being given to the possible
+presence of water in the material in the car as received and also to the
+possible addition of water during the steaming. The Committee knows of
+no direct method for sampling a hard-frozen tank car of tallow in a
+satisfactory manner.
+
+(_b_) _When contents are liquid._ The sample taken is to be a 50-lb.
+composite made up of numerous small samples taken from the top, bottom
+and intermediate points by means of a bottle or metal container with
+removable stopper or top. This device attached to a suitable pole is
+lowered to the various desired depths, when the stopper or top is
+removed and the container allowed to fill. The 50-lb. sample thus
+obtained is handled as under (1).
+
+In place of the device described above, any sampler capable of taking a
+sample from the top, bottom, and center, or from a section through car,
+may be used.
+
+(_c_) _When contents are in semi-solid condition, or when stearine has
+separated from liquid portions._ In this case, a combination of (_a_)
+and (_b_) may be used or by agreement of the parties the whole may be
+melted and procedure (_b_) followed.
+
+
+BARRELS, TIERCES, CASKS, DRUMS, AND OTHER PACKAGES.
+
+All packages shall be sampled, unless by special agreement the parties
+arrange to sample a lesser number; but in any case not less than 10 per
+cent of the total number shall be sampled. The total sample taken shall
+be at least 20 lbs. in weight for each 100 barrels, or equivalent.
+
+1. BARRELS, TIERCES AND CASKS--(_a_) _When contents are solid._ The
+small samples shall be taken by a tryer through the bunghole or through
+a special hole bored in the head or side for the purpose, with a 1-in.
+or larger auger. Care should be taken to avoid and eliminate all borings
+and chips from the sample. The tryer is inserted in such a way as to
+reach the head of the barrel, tierce, or cask. The large sample is
+softened, mixed and handled according to TANK CARS (1).
+
+(_b_) _When contents are liquid._ In this case use is made of a glass
+tube with constricted lower end. This is inserted slowly and allowed to
+fill with the liquid, when the upper end is closed and the tube
+withdrawn, the contents being allowed to drain into the sample
+container. After the entire sample is taken it is thoroughly mixed and
+handled according to TANK CARS (1).
+
+(_c_) _When contents are semi-solid._ In this case the tryer or a glass
+tube with larger outlet is used, depending on the degree of fluidity.
+
+(_d_) _Very hard materials, such as natural and artificial stearines._
+By preference the barrels are stripped and samples obtained by breaking
+up contents of at least 10 per cent of the packages. This procedure is
+to be followed also in the case of cakes shipped in sacks. When shipped
+in the form of small pieces in sacks they can be sampled by grab
+sampling and quartering. In all cases the final procedure is as outlined
+under TANK CARS (1).
+
+2. DRUMS--Samples are to be taken as under (1), use being made of the
+bunghole. The tryer or tube should be sufficiently long to reach to the
+ends of the drum.
+
+3. OTHER PACKAGES--Tubs, pails and other small packages not mentioned
+above are to be sampled by tryer or tube (depending on fluidity) as
+outlined above, the tryer or tube being inserted diagonally whenever
+possible.
+
+4. MIXED LOTS AND PACKAGES--When lots of tallow or other fats are
+received in packages of various shapes and sizes, and especially wherein
+the fat itself is of variable composition, such must be left to the
+judgment of the sampler. If variable, the contents of each package
+should be mixed as thoroughly as possible and the amount of the
+individual samples taken made proportional to the sizes of the packages.
+
+
+Analysis.
+
+
+SAMPLE.
+
+The sample must be representative and at least three pounds in weight
+and taken in accordance with the STANDARD METHODS FOR THE SAMPLING OF
+COMMERCIAL FATS AND OILS. It must be kept in an air-tight container, in
+a dark, cool place.
+
+Soften the sample if necessary by means of a gentle heat, taking care
+not to melt it. When sufficiently softened, mix the sample thoroughly by
+means of a mechanical egg beater or other equally effective mechanical
+mixer.
+
+
+MOISTURE AND VOLATILE MATTER.
+
+APPARATUS: _Vacuum Oven_--The Committee Standard Oven.
+
+DESCRIPTION--The Standard F. A. C. Vacuum Oven has been designed with
+the idea of affording a simple and compact vacuum oven which will give
+as uniform temperatures as possible on the shelf. As the figure shows,
+it consists of an iron casting of rectangular sections with hinged front
+door made tight by means of a gasket and which can be lowered on opening
+the oven so as to form a shelf on which samples may be rested. The oven
+contains but one shelf which is heated from above as well as below by
+means of resistance coils. Several thermometer holes are provided in
+order to ascertain definitely the temperature at different points on the
+shelf. In a vacuum oven where the heating is done almost entirely by
+radiation it is difficult to maintain uniform temperatures at all
+points, but the F. A. C. oven accomplishes this rather better than most
+vacuum ovens. Larger ovens containing more than one shelf have been
+tried by the Committee, but have been found to be lacking in temperature
+uniformity and means of control. The entire oven is supported by means
+of a 4-in. standard pipe which screws into the base of the oven and
+which in turn is supported by being screwed into a blind flange of
+suitable diameter which rests on the floor or work table.
+
+_Moisture Dish_--A shallow, glass dish, lipped, beaker form,
+approximately 6 to 7 cm. diameter and 4 cm. deep, shall be standard.
+
+DETERMINATION--Weigh out 5 grams (= 0.2 g. of the prepared sample) into
+a moisture dish. Dry to constant weight in _vacuo_ at a uniform
+temperature, not less than 15deg. C. nor more than 20deg. C. above the
+boiling point of water at the working pressure, which must not exceed
+100 mm. of mercury.[25] Constant weight is attained when successive
+dryings for 1-hr. periods show an additional loss of not more that 0.05
+per cent. Report loss in weight as MOISTURE AND VOLATILE MATTER.[26]
+
+[Illustration: STANDARD VACUUM OVEN]
+
+The vacuum-oven method cannot be considered accurate in the case of fats
+of the coconut oil group containing free acid and the Committee
+recommends that it be used only for oils of this group when they contain
+less than 1 per cent free acid. In the case of oils of this group
+containing more than 1 per cent free acid, recourse should be had
+temporarily to the routine control method for moisture and volatile
+matter[27] until the Committee develops a more satisfactory method.
+
+The air-oven method cannot be considered even approximately accurate in
+the case of the drying and semi-drying oils and those of the coconut oil
+group. Therefore, in the case of such oils as cottonseed oil, maize oil
+(corn oil), soy bean oil, linseed oil, coconut oil, palm kernel oil,
+etc., the vacuum-oven method should always be used, except in the case
+of fats of the coconut group containing more than 1 per cent free acid,
+as noted above.
+
+
+INSOLUBLE IMPURITIES.
+
+Dissolve the residue from the moisture and volatile matter determination
+by heating it on a steam bath with 50 cc. of kerosene. Filter the
+solution through a Gooch crucible properly prepared with asbestos,[28]
+wash the insoluble matter five times with 10-cc. portions of hot
+kerosene, and finally wash the residual kerosene out thoroughly with
+petroleum ether. Dry the crucible and contents to constant weight, as in
+the determination of moisture and volatile matter and report results as
+INSOLUBLE IMPURITIES.
+
+
+SOLUBLE MINERAL MATTER.
+
+Place the combined kerosene filtrate and kerosene washings from the
+insoluble impurities determination in a platinum dish. Place in this an
+ashless filter paper folded in the form of a cone, apex up. Light the
+apex of the cone, whereupon the bulk of the kerosene burns quietly. Ash
+the residue in a muffle, to constant weight, taking care that the
+decomposition of alkaline earth carbonates is complete, and report the
+result as SOLUBLE MINERAL MATTER.[29] When the percentage of soluble
+mineral matter amounts to more than 0.1 per cent, multiply the
+percentage by 10 and add this amount to the percentage of free fatty
+acids as determined.[30]
+
+
+FREE FATTY ACIDS.
+
+The ALCOHOL[31] used shall be approximately 95 per cent ethyl alcohol,
+freshly distilled from sodium hydroxide, which with phenolphthalein
+gives a definite and distinct end-point.
+
+DETERMINATION--Weigh 1 to 15 g. of the prepared sample into an
+Erlenmeyer flask, using the smaller quantity in the case of
+dark-colored, high acid fats. Add 50 to 100 cc. hot, neutral alcohol,
+and titrate with _N_/2, _N_/4 or _N_/10 sodium hydroxide depending on
+the fatty acid content, using phenolphthalein as indicator. Calculate to
+oleic acid, except that in the case of palm oil the results may also be
+expressed in terms of palmitic acid, clearly indicating the two methods
+of calculation in the report. In the case of coconut and palm kernel
+oils, calculate to and report in terms of lauric acid in addition to
+oleic acid, clearly indicating the two methods of calculation in the
+report. In the case of fats or greases containing more than 0.1 per cent
+of soluble mineral matter, add to the percentages of free fatty acids as
+determined 10 times the percentage of bases in the soluble mineral
+matter as determined.[30] This addition gives the equivalent of fatty
+acids combined with the soluble mineral matter.
+
+
+TITER.
+
+STANDARD THERMOMETER--The thermometer is graduated at zero and in tenth
+degrees from 10deg. C. to 65deg. C., with one auxiliary reservoir at the
+upper end and another between the zero mark and the 10deg. mark. The
+cavity in the capillary tube between the zero mark and the 10deg. mark
+is at least 1 cm. below the 10deg. mark, the 10deg. mark is about 3 or 4
+cm. above the bulb, the length of the thermometer being about 37 cm.
+over all. The thermometer has been annealed for 75 hrs. at 450deg. C.
+and the bulb is of Jena normal 16''' glass, or its equivalent,
+moderately thin, so that the thermometer will be quick-acting. The bulb
+is about 3 cm. long and 6 mm. in diameter. The stem of the thermometer
+is 6 mm. in diameter and made of the best thermometer tubing, with scale
+etched on the stem, the graduation is clear-cut and distinct, but quite
+fine. The thermometer must be certified by the U. S. Bureau of
+Standards.
+
+GLYCEROL CAUSTIC SOLUTION--Dissolve 250 g. potassium hydroxide in 1900
+cc. dynamite glycerin with the aid of heat.
+
+DETERMINATION--Heat 75 cc. of the glycerol-caustic solution to 150deg.
+C. and add 50 g. of the melted fat. Stir the mixture well and continue
+heating until the melt is homogeneous, at no time allowing the
+temperature to exceed 150deg. C. Allow to cool somewhat and carefully
+add 50 cc. 30 per cent sulfuric acid. Now add hot water and heat until
+the fatty acids separate out perfectly clear. Draw off the acid water
+and wash the fatty acids with hot water until free from mineral acid,
+then filter and heat to 130deg. C. as rapidly as possible while
+stirring. Transfer the fatty acids, when cooled somewhat, to a 1-in. by
+4-in. titer tube, placed in a 16-oz. salt-mouth bottle of clear glass,
+fitted with a cork that is perforated so as to hold the tube rigidly
+when in position. Suspend the titer thermometer so that it can be used
+as a stirrer and stir the fatty acids slowly (about 100 revolutions per
+minute) until the mercury remains stationary for 30 seconds. Allow the
+thermometer to hang quietly with the bulb in the center of the tube and
+report the highest point to which the mercury rises as the titer of the
+fatty acids. The titer should be made at about 20deg. C. for all fats
+having a titer above 30deg. C. and at 10deg. C. below the titer for all
+other fats. Any convenient means may be used for obtaining a temperature
+of 10deg. below the titer of the various fats. The committee recommends
+first of all a chill room for this purpose; second, an artificially
+chilled small chamber with glass window; third, immersion of the
+salt-mouth bottle in water or other liquid of the desired temperature.
+
+
+UNSAPONIFIABLE MATTER.
+
+EXTRACTION CYLINDER--The cylinder shall be glass-stoppered, graduated at
+40 cc., 80 cc. and 130 cc., and of the following dimensions: diameter
+about 1-3/8 in., height about 12 in.
+
+PETROLEUM ETHER--Redistilled petroleum ether, boiling under 75deg. C.,
+shall be used. A blank must be made by evaporating 250 cc. with about
+0.25 g. of stearine or other hard fat (previously brought to constant
+weight by heating) and drying as in the actual determination. The blank
+must not exceed a few milligrams.
+
+DETERMINATION--Weigh 5 g. (+-0.20 g.) of the prepared sample into a
+200-cc. Erlenmeyer flask, add 30 cc. of redistilled 95 per cent
+(approximately) ethyl alcohol and 5 cc. of 50 per cent aqueous potassium
+hydroxide, and boil the mixture for one hour under a reflux condenser.
+Transfer to the extraction cylinder and wash to the 40-cc. mark with
+redistilled 95 per cent ethyl alcohol. Complete the transfer, first with
+warm, then with cold water, till the total volume amounts to 80 cc. Cool
+the cylinder and contents to room temperature and add 50 cc. of
+petroleum ether. Shake _vigorously_ for one minute and allow to settle
+until both layers are clear, when the volume of the upper layer should
+be about 40 cc. Draw off the petroleum ether layer as closely as
+possible by means of a slender glass siphon into a separatory funnel of
+500 cc. capacity. Repeat extraction at least four more times, using 50
+cc. of petroleum ether each time. More extractions than five are
+necessary where the unsaponifiable matter runs high, say over 5 per
+cent, and also in some cases where it is lower than 5 per cent, but is
+extracted with difficulty. Wash the combined extracts in a separatory
+funnel three times with 25-cc. portions of 10 per cent alcohol, shaking
+vigorously each time. Transfer the petroleum ether extract to a
+wide-mouth tared flask or beaker, and evaporate the petroleum ether on a
+steam bath in an air current. Dry as in the method for MOISTURE AND
+VOLATILE MATTER. Any blank must be deducted from the weight before
+calculating unsaponifiable matter. Test the final residue for solubility
+in 50 cc. petroleum ether at room temperature. Filter and wash free from
+the insoluble residue, if any, evaporate and dry in the same manner as
+before. The Committee wishes to emphasize the necessity of thorough and
+vigorous shaking in order to secure accurate results. The two phases
+must be brought into the most intimate contact possible, otherwise low
+and disagreeing results may be obtained.
+
+
+IODINE NUMBER--WIJS METHOD.
+
+PREPARATION OF REAGENTS--_Wijs Iodine Solution_--Dissolve 13.0 g. of
+resublimed iodine in one liter of C. P. glacial acetic acid and pass in
+washed and dried chlorine gas until the original thiosulfate titration
+of the solution is not quite doubled. The solution is then preserved in
+amber glass-stoppered bottles, sealed with paraffin until ready for use.
+
+Mark the date on which the solution is prepared on the bottle or bottles
+and do not use Wijs solution which is more than 30 days old.
+
+There should be no more than a slight excess of iodine, and no excess of
+chlorine. When the solution is made from iodine and chlorine, this point
+can be ascertained by not quite doubling the titration.[32]
+
+The glacial acetic acid used for preparation of the Wijs solution should
+be of 99.0 to 99.5 per cent strength. In case of glacial acetic acids of
+somewhat lower strength, the Committee recommends freezing and
+centrifuging or draining as a means of purification.
+
+_N_/10 _Sodium Thiosulfate Solution_--Dissolve 24.8 g. of C. P. sodium
+thiosulfate in recently boiled distilled water and dilute with the same
+to one liter at the temperature at which the titrations are to be made.
+
+_Starch Paste_--Boil 1 g. of starch in 200 cc. of distilled water for 10
+min. and cool to room temperature.
+
+An improved starch solution may be prepared by autoclaving 2 g. of
+starch and 6 g. of boric acid dissolved in 200 cc. water at 15 lbs.
+pressure for 15 min. This solution has good keeping qualities.
+
+_Potassium Iodide Solution_--Dissolve 150 g. of potassium iodide in
+water and make up to one liter.
+
+_N_/10 _Potassium Bichromate_--Dissolve 4.903 g. of C. P. potassium
+bichromate in water and make the volume up to one liter at the
+temperature at which titrations are to be made.
+
+The Committee calls attention to the fact that occasionally potassium
+bichromate is found containing sodium bichromate, although this is of
+rare occurrence. If the analyst suspects that he is dealing with an
+impure potassium bichromate, the purity can be ascertained by titration
+against re-sublimed iodine. However, this is unnecessary in the great
+majority of cases.
+
+_Standardization of the Sodium Thiosulfate Solution_--Place 40 cc. of
+the potassium bichromate solution, to which has been added 10 cc. of the
+solution of potassium iodide, in a glass-stoppered flask. Add to this 5
+cc. of strong hydro-chloric acid. Dilute with 100 cc. of water, and
+allow the _N_/10 sodium thiosulfate to flow slowly into the flask until
+the yellow color of the liquid has almost disappeared. Add a few drops
+of the starch paste, and with constant shaking continue to add the
+_N_/10 sodium thiosulfate solution until the blue color just disappears.
+
+DETERMINATION--Weigh accurately from 0.10 to 0.50 g. (depending on the
+iodine number) of the melted and filtered sample into a clean, dry,
+16-oz. glass-stoppered bottle containing 15-20 cc. of carbon
+tetrachloride or chloroform. Add 25 cc. of iodine solution from a
+pipette, allowing to drain for a definite time. The excess of iodine
+should be from 50 per cent to 60 per cent of the amount added, that is,
+from 100 per cent to 150 per cent of the amount absorbed. Moisten the
+stopper with a 15 per cent potassium iodide solution to prevent loss of
+iodine or chlorine but guard against an amount sufficient to run down
+inside the bottle. Let the bottle stand in a dark place for 1/2 hr. at a
+uniform temperature. At the end of that time add 20 cc. of 15 per cent
+potassium iodide solution and 100 cc. of distilled water. Titrate the
+iodine with _N_/10 sodium thiosulfate solution which is added gradually,
+with constant shaking, until the yellow color of the solution has almost
+disappeared. Add a few drops of starch paste and continue titration
+until the blue color has entirely disappeared. Toward the end of the
+reaction stopper the bottle and shake violently so that any iodine
+remaining in solution in the tetrachloride or chloroform may be taken up
+by the potassium iodide solution. Conduct two determinations on blanks
+which must be run in the same manner as the sample except that no fat is
+used in the blanks. Slight variations in temperature quite appreciably
+affect the titer of the iodine solution, as acetic acid has a high
+coefficient of expansion. It is, therefore, essential that the blanks
+and determinations on the sample be made at the same time. The number of
+cc. of standard thiosulfate solution required by the blank, less the
+amount used in the determination, gives the thiosulfate equivalent of
+the iodine absorbed by the amount of sample used in the determination.
+Calculate to centigrams of iodine absorbed by 1 g. of sample (= per cent
+iodine absorbed).
+
+DETERMINATION, TUNG OIL--Tung oil shows an erratic behavior with most
+iodine reagents and this is particularly noticeable in the case of the
+Hanus reagent which is entirely unsuitable for determining the iodine
+number of this oil since extremely high and irregular results are
+obtained. The Huebl solution shows a progressive absorption up to 24 hrs.
+and probably for a longer time but the period required is entirely too
+long for a chemical determination. The Wijs solution gives good results
+if the following precautions are observed:
+
+Weigh out 0.15 +- 0.05 g., use an excess of 55 +- 3 per cent Wijs
+solution. Conduct the absorption at a temperature of 20-25deg. C. for 1
+hr. In other respects follow the instructions detailed above.
+
+
+SAPONIFICATION NUMBER (KOETTSTORFER NUMBER).
+
+PREPARATION OF REAGENTS. _N/2 Hydrochloric Acid_--Carefully
+standardized.
+
+_Alcoholic Potassium Hydroxide Solution_--Dissolve 40 g. of pure
+potassium hydroxide in one liter of 95 per cent redistilled alcohol (by
+volume). The alcohol should be redistilled from potassium hydroxide over
+which it has been standing for some time, or with which it has been
+boiled for some time, using a reflux condenser. The solution must be
+clear and the potassium hydroxide free from carbonates.
+
+DETERMINATION--Weigh accurate about 5 g. of the filtered sample into a
+250 to 300 cc. Erlenmeyer flask. Pipette 50 cc. of the alcoholic
+potassium hydroxide solution into the flask, allowing the pipette to
+drain for a definite time. Connect the flask with an air condenser and
+boil until the fat is completely saponified (about 30 minutes). Cool and
+titrate with the _N_/2 hydrochloric acid, using phenolphthalein as an
+indicator. Calculate the Koettstorfer number (mg. of potassium hydroxide
+required to saponify 1 g. of fat). Conduct 2 or 3 blank determinations,
+using the same pipette and draining for the same length of time as
+above.
+
+
+MELTING POINT.
+
+APPARATUS--_Capillary tubes_ made from 5 mm. inside diameter thin-walled
+glass tubing drawn out to 1 mm. inside diameter. Length of capillary
+part of tubes to be about 5 cm. Length of tube over all 8 cm.
+
+_Standard thermometer_ graduated in tenths of a degree.
+
+_600 cc. beaker._
+
+DETERMINATION--The sample should be clear when melted and entirely free
+from moisture, or incorrect results will be obtained.
+
+Melt and thoroughly mix the sample. Dip three of the capillary tubes
+above described in the oil so that the fat in the tube stands about 1
+cm. in height. Now fuse the capillary end carefully by means of a small
+blast flame and allow to cool. These tubes are placed in a refrigerator
+over night at a temperature of from 40 to 50deg. F. They are then
+fastened by means of a rubber band or other suitable means to the bulb
+of a thermometer graduated in tenths of a degree. The thermometer is
+suspended in a beaker of water (which is agitated by air or other
+suitable means) so that the bottom of the bulb of the thermometer is
+immersed to a depth of about 3 cm. The temperature of the water is
+increased gradually at the rate of about 1deg. per minute.
+
+The point at which the sample becomes opalescent is first noted and the
+heating continued until the contents of the tube becomes uniformly
+transparent. The latter temperature is reported as the melting point.
+
+Before finally melting to a perfectly clear fluid, the sample becomes
+opalescent and usually appears clear at the top, bottom, and sides
+before becoming clear at the center. The heating is continued until the
+contents of the tube become uniformly clear and transparent. This
+temperature is reported as the melting point.[33] It is usually only a
+fraction of a degree above the opalescent point noted. The thermometer
+should be read to the nearest 1/2deg. C., and in addition this
+temperature may be reported to the nearest degree Fahrenheit if desired.
+
+
+CLOUD TEST.
+
+PRECAUTIONS--(1) The oil must be perfectly dry, because the presence of
+moisture will produce a turbidity before the clouding point is reached.
+
+(2) The oil must be heated to 150deg. C. over a free flame, immediately
+before making the test.
+
+(3) There must not be too much discrepancy between the temperature of
+the bath and the clouding point of the oil. An oil that will cloud at
+the temperature of hydrant water should be tested in a bath of that
+temperature. An oil that will cloud in a mixture of ice and water should
+be tested in such a bath. An oil that will not cloud in a bath of ice
+and water must be tested in a bath of salt, ice, and water.
+
+DETERMINATION--The oil is heated in a porcelain casserole over a free
+flame to 150deg. C., stirring with the thermometer. As soon as it can be
+done with safety, the oil is transferred to a 4 oz. oil bottle, which
+must be perfectly dry. One and one-half ounces of the oil are sufficient
+for the test. A dry centigrade thermometer is placed in the oil, and the
+bottle is then cooled by immersion in a suitable bath. The oil is
+constantly stirred with the thermometer, taking care not to remove the
+thermometer from the oil at any time during the test, so as to avoid
+stirring air bubbles into the oil. The bottle is frequently removed from
+the bath for a few moments. The oil must not be allowed to chill on the
+sides and bottom of the bottle. This is effected by constant and
+vigorous stirring with the thermometer. As soon as the first permanent
+cloud shows in the body of the oil, the temperature at which this cloud
+occurs is noted.
+
+With care, results concordant to within 1/2deg. C. can be obtained by
+this method. A Fahrenheit thermometer is sometimes used because it has
+become customary to report results in degrees Fahrenheit.
+
+The oil must be tested within a short time after heating to 150deg. C.
+and a re-test must always be preceded by reheating to that temperature.
+The cloud point should be approached as quickly as possible, yet not so
+fast that the oil is frozen on the sides or bottom of the bottle before
+the cloud test is reached.
+
+
+Notes on the Above Methods.
+
+
+SAMPLING.
+
+The standard size of sample adopted by the committee is at least 3 lbs.
+in weight. The committee realizes that this amount is larger than any
+samples usually furnished even when representing shipments of from
+20,000 to 60,000 lbs. but it believes that the requirement of a larger
+sample is desirable and will work toward uniform and more concordant
+results in analysis. It will probably continue to be the custom of the
+trade to submit smaller buyers' samples than required by the committee,
+but these are to be considered only as samples for inspection and not
+for analysis. The standard analytical sample must consist of 3 lbs. or
+more.
+
+The reasons for keeping samples in a dark, cool place are obvious. This
+is to prevent any increase in rancidity and any undue increase in free
+fatty acids. In the case of many fats the committee has found in its
+co-operative analytical work that free acid tends to increase very
+rapidly. This tendency is minimized by low temperatures.
+
+
+MOISTURE AND VOLATILE MATTER.
+
+After careful consideration the committee has decided that moisture is
+best determined in a vacuum oven of the design which accompanies the
+above report. Numerous results on check samples have confirmed the
+committee's conclusions. The oven recommended by the committee is
+constructed on the basis of well-known principles and it is hoped that
+this type will be adopted generally by chemists who are called upon to
+analyze fats and oils. The experiments of the committee indicate that it
+is a most difficult matter to design a vacuum oven which will produce
+uniform temperatures throughout; and one of the principal ideas in the
+design adopted is uniformity of temperature over the entire single
+shelf. This idea has not quite been realized in practice but,
+nevertheless, the present design approaches much closer to the ideal
+than other vacuum ovens commonly used. In the drawing the essential
+dimensions are those between the heating units and the shelf and the
+length and breadth of the outer casting. The standard Fat Analysis
+Committee Oven (F. A. C. Oven) can be furnished by Messrs. E. H. Sargent
+& Company, 125 West Lake street, Chicago.
+
+The committee realizes that for routine work a quicker method is
+desirable and has added one such method and has also stated the
+conditions under which comparable results can be obtained by means of
+the ordinary well-ventilated air oven held at 105 to 110deg. C. However,
+in accordance with a fundamental principle adopted by the committee at
+its first meeting, only one standard method is adopted and declared
+official for each determination.
+
+The committee realizes that in the case of all methods for determining
+moisture by means of loss on heating there may be a loss due to volatile
+matter (especially fatty acids) other than water. The title of the
+determination MOISTURE AND VOLATILE MATTER indicates this idea, but any
+considerable error from this source may occur only in the case of high
+acid fats and oils and particularly those containing lower fatty acids
+such as coconut and palm kernel oil. In the case of extracted greases
+which have not been properly purified, some of the solvent may also be
+included in the moisture and volatile matter determination, but inasmuch
+as the solvent, usually a petroleum product, can only be considered as
+foreign matter, for commercial purposes, it is entirely proper to
+include it with the moisture.
+
+The committee has also considered the various distillation methods for
+the determination of moisture in fats and oils, but since according to
+the fundamental principles which it was endeavoring to follow it could
+only standardize one method, it was decided that the most desirable one
+on the whole was the vacuum-oven method as given. There are cases
+wherein a chemist may find it desirable to check a moisture
+determination or investigate the moisture content of a fat or oil
+further by means of one of the distillation methods.
+
+However, in co-operative work the distillation method in various types
+of apparatus has not yielded satisfactory results. The difficulties
+appear to be connected with a proper choice of solvent and particularly
+with the tendency of drops of water to adhere to various parts of the
+glass apparatus instead of passing on to the measuring device. When
+working on coconut oil containing a high percentage of free fatty acids,
+concordant results could not be obtained by the various members of the
+committee when working with identical samples, solvents and apparatus.
+
+On the other hand, the committee found by individual work, co-operative
+work and collaborative work by several members of the committee in one
+laboratory, that the old, well-known direct heating method (which the
+committee has designated the hot plate method) yielded very satisfactory
+results on all sorts of fats and oils including emulsions such as butter
+and oleomargarine and even on coconut oil samples containing 15 to 20
+per cent free fatty acids and 5 to 6 per cent of moisture.
+Unfortunately, this method depends altogether on the operator's skill
+and while the method may be taught to any person whether a chemist or
+not so that he can obtain excellent results with it, it is difficult to
+give a sufficiently, complete description of it so that any chemist
+anywhere after reading the description could follow it successfully. The
+method is undoubtedly worthy of much confidence in careful hands. It is
+quick, accurate and reliable. It is probably the best single method for
+the determination of moisture in all sorts of samples for routine
+laboratory work. On account of this fact the committee desires to
+announce its willingness to instruct any person in the proper use of the
+method who desires to become acquainted with it and who will visit any
+committee member's laboratory.
+
+
+INSOLUBLE IMPURITIES.
+
+This determination, the title for which was adopted after careful
+consideration, determines the impurities which have generally been known
+as dirt, suspended matter, suspended solids, foreign solids, foreign
+matter, etc., in the past. The first solvent recommended by the
+committee is hot kerosene to be followed by petroleum ether kept at
+ordinary room temperature. Petroleum ether, cold or only slightly warm,
+is not a good fat and metallic soap solvent, whereas hot kerosene
+dissolves these substances readily, and for this reason the committee
+has recommended the double solvent method so as to exclude metallic
+soaps which are determined below as soluble mineral matter.
+
+
+SOLUBLE MINERAL MATTER.
+
+Soluble mineral matter represents mineral matter combined with fatty
+acids in the form of soaps in solution in the fat or oil. Formerly, this
+mineral matter was often determined in combination by weighing the
+separated metallic soap or by weighing it in conjunction with the
+insoluble impurities. Since the soaps present consist mostly of lime
+soap, it has been customary to calculate the lime present therein by
+taking 0.1 the weight of the total metallic soaps. The standard method
+as given above is direct and involves no calculation. The routine method
+given in the note has been placed among the methods for the reason that
+it is used in some laboratories, but has not been adopted as a standard
+method in view of the fact that the committee has made it a rule to
+adopt only one standard method. It should be pointed out, however, that
+the method cannot be considered accurate for the reason that insoluble
+impurities may vary from sample to sample to a considerable extent and
+the error due to the presence of large particles of insoluble impurities
+is thus transferred to the soluble mineral matter. The committee has
+found one type of grease (naphtha bone grease) which shows most unusual
+characteristics. The type sample contains 4.3 per cent soluble mineral
+matter by the committee method which would be equivalent to 43.0 per
+cent free fatty acid. The kerosene and gasoline filtrate was
+particularly clear, nevertheless the ash was found to contain 36.43 per
+cent P_{2}O_{5} equivalent to 79.60 per cent of Ca_{3}(PO_{4})_{2} and
+9.63 per cent of Fe_{2}O_{3}. The method, therefore, determines the
+soluble mineral matter in this case satisfactorily but the factor 10 is
+not applicable for calculating the fatty acids combined therewith. It is
+necessary, therefore, in order to determine the fatty acids combined
+with soluble mineral matter in the original sample to determine the
+actual bases in the soluble mineral matter as obtained by ashing the
+kerosene and gasoline filtrate. To the bases so determined the factor 10
+can then be applied.
+
+
+FREE FATTY ACID.
+
+The fatty acid method adopted is sufficiently accurate for commercial
+purposes. In many routine laboratories the fat or oil is measured and
+not weighed, but the committee recommends weighing the sample in all
+cases. For scientific purposes the result is often expressed as "acid
+number," meaning the number of milligrams of KOH required to neutralize
+the free acids in one gram of fat, but the commercial practice has been,
+and is, to express the fatty acids as oleic acid or in the case of palm
+oil, as palmitic acid, in some instances. The committee sees no
+objection to the continuation of this custom so long as the analytical
+report clearly indicates how the free acid is expressed. For a more
+exact expression of the free acid in a given fat, the committee
+recommends that the ratio of acid number to saponification number be
+used. This method of expressing results is subject to error when
+unsaponifiable fatty matter is present, since the result expresses the
+ratio of free fatty acid to total saponifiable fatty matter present.
+
+
+TITER.
+
+At the present time the prices of glycerol and caustic potash are
+abnormally high, but the committee has considered that the methods
+adopted are for normal times and normal prices. For routine work during
+the period of high prices the following method may be used for preparing
+the fatty acids and is recommended by the committee:
+
+Fifty grams of fat are saponified with 60 cc. of a solution of 2 parts
+of methyl alcohol to 1 of 50 per cent NaOH. The soap is dried,
+pulverized and dissolved in 1000 cc. of water in a porcelain dish and
+then decomposed with 25 cc. of 75 per cent sulphuric acid. The fatty
+acids are boiled until clear oil is formed and then collected and
+settled in a 150-cc. beaker and filtered into a 50-cc. beaker. They are
+then heated to 130deg. C. as rapidly as possible with stirring, and
+transferred, after they have cooled somewhat, to the usual 1-in. by
+4-in. titer tube.
+
+The method of taking the titer, including handling the thermometer, to
+be followed is the same as that described in the standard method. Even
+at present high prices many laboratories are using the glycerol-caustic
+potash method for preparing the fatty acids, figuring that the saving of
+time more than compensates for the extra cost of the reagents. Caustic
+soda cannot be substituted for caustic potash in the glycerol method.
+
+UNSAPONIFIABLE MATTER.
+
+The committee has considered unsaponifiable matter to include those
+substances frequently found dissolved in fats and oils which are not
+saponified by the caustic alkalies and which at the same time are
+soluble in the ordinary fat solvents. The term includes such substances
+as the higher alcohols, such as cholesterol which is found in animal
+fats, phytosterol found in some vegetable fats, paraffin and petroleum
+oils, etc. UNSAPONIFIABLE MATTER should not be confused in the lay mind
+with INSOLUBLE IMPURITIES OR SOLUBLE MINERAL MATTER.
+
+The method adopted by the committee has been selected only after the
+most careful consideration of other methods, such as the dry extraction
+method and the wet method making use of the separatory funnel. At first
+consideration the dry extraction process would seem to offer the best
+basis for an unsaponifiable matter method, but in practice it has been
+found absolutely impossible for different analysts to obtain agreeing
+results when using any of the dry extraction methods proposed.
+Therefore, this method had to be abandoned after numerous trials,
+although several members of the committee strongly favored it in the
+beginning.
+
+IODINE NUMBER--The iodine number adopted by the committee is that
+determined by the well-known Wijs method. This method was adopted after
+careful comparison with the Hanus and Huebl methods. The Huebl method was
+eliminated from consideration almost at the beginning of the committee's
+work for the reason that the time required for complete absorption of
+the iodine is unnecessarily long and, in fact, even after absorption has
+gone on over night, it is apparently not complete. In the case of the
+Hanus and Wijs methods complete absorption takes place in from 15
+minutes to an hour, depending on conditions. Formerly, many chemists
+thought the Hanus solution rather easier to prepare than the Wijs
+solution, but the experience of the committee was that the Wijs solution
+was no more difficult to prepare than the Hanus. Furthermore, absorption
+of iodine from the Wijs solution appeared to take place with greater
+promptness and certainty than from the Hanus and was complete in a
+shorter time. Results by the Wijs method were also in better agreement
+in the case of oils showing high iodine absorption than with the Hanus
+solution and showed a slightly higher iodine absorption for the same
+length of time. However, the difference was not great. The committee
+investigated the question of substitution since it has been suggested
+that in case of the Wijs solution substitution of iodine in the organic
+molecule might occur, and found no evidence of this in the time required
+for the determination, namely, 1/2 hr., or even for a somewhat longer
+period. One member of the committee felt that it was not desirable to
+introduce the Wijs method into these standard methods since the Hanus
+method was already standardized by the Association of Official
+Agricultural Chemists, but the committee felt that it must follow the
+principle established at the commencement of its work, namely, that of
+adopting the method which appeared to be the best from all standpoints,
+taking into consideration accuracy, convenience, simplicity, time,
+expense, etc., without allowing precedent to have the deciding vote.
+
+IODINE NUMBER, TUNG OIL--The committee has made an extensive study of
+the application of the Wijs method to the determination of iodine value
+in the case of tung oil with the result that it recommends the method
+for this oil but has thought it desirable to limit the conditions under
+which the determination is conducted rather narrowly, although
+reasonably good results are obtained by the committee method without
+making use of the special limitations.
+
+The co-operative work of the committee and the special investigations
+conducted by individual members bring out the following points:
+
+_Influence of Temperature_--From 16deg. C. to 30deg. C. there is a
+moderate increase in the absorption, but above 30deg. the increase is
+rather rapid so that it was thought best to limit the temperature in the
+case of tung oil to 20deg. to 25deg. C.
+
+_Influence of Time_--The absorption increases with the time but
+apparently complete absorption, so far as unsaturated bonds are
+concerned, occurs well within one hour's time. Consequently, one hour
+was set as the practical limit.
+
+_Influence of Excess_--The excess of iodine solution also tends to
+increase the iodine number, hence the Committee thought it necessary to
+limit the excess rather rigidly to 55 +- 3 per cent, although with
+greater latitude results were reasonably good.
+
+_Influence of Age of Solution_--Old solutions tend to give low results
+although up to 2 mo. no great differences were observed. Nevertheless,
+it was thought best to limit the age of the solution to 30 days--long
+enough for all practical purposes.
+
+_Amount of Sample_--As a practical amount of sample to be weighed out
+the Committee decided on 0.15 g. with a tolerance of 0.05 g. in either
+direction according to preference. In other words, the amount of sample
+to be taken for the determination to be from 0.1 to 0.2 g. in the
+discretion of the analyst.
+
+The Committee's study of the Huebl method which has been adopted by the
+Society for Testing Materials in the case of tung oil indicates that
+this method when applied to tung oil is subject to the same influences
+as the Wijs method and it has the additional very serious disadvantage
+of requiring a long period of time for absorption which cannot be
+considered reasonable for a modern analytical method. When using the
+Huebl solution, the absorption is not complete in the case of tung oil at
+3, 7, 18 or even 24 hrs.
+
+The Hanus method in the case of tung oil gives very high and erratic
+results, as high as 180 to 240 in ordinary cases for an oil whose true
+iodine number is about 165.
+
+
+MELTING POINT.
+
+A melting point is the temperature at which a solid substance assumes
+the liquid condition. If the solid is a pure substance in the
+crystalline condition the melting point is sharp and well defined for
+any given pressure. With increased pressure the melting point is lowered
+or raised, depending on whether the substance contracts or expands in
+melting. The lowering or raising of the melting point with pressure is
+very slight and ordinarily is not taken into consideration.
+Melting-point determinations are commonly carried out under ordinary
+atmospheric pressures without correction. The general effect of soluble
+impurities is to lower the melting point, and this holds true whether
+the impurity has a higher or lower melting point than the pure substance
+(solvent). Thus if a small amount of stearic acid be added to liquid
+palmitic acid and the solution frozen, the melting point of this solid
+will be lower than that of palmitic acid. Likewise the melting point of
+stearic acid is lowered by the addition of a small amount of palmitic
+acid. A eutectic mixture results when two components solidify
+simultaneously at a definite temperature. Such a mixture has a constant
+melting point and because of this and also because both solid and liquid
+phases have the same composition, eutectic mixtures were formerly looked
+upon as compounds. The phenomenon of double melting points has been
+observed in the case of a number of glycerides. Such a glyceride when
+placed in the usual capillary tube and subjected to increasing
+temperature quickly resolidifies only to melt again and remain melted at
+a still higher temperature. This phenomenon has not yet been
+sufficiently investigated to afford a satisfactory explanation.
+
+Non-crystalline substances such as glass, sealing wax and various other
+waxes and wax mixtures, and most colloidal substances do not exhibit a
+sharp melting point, but under the application of heat first soften very
+gradually and at a considerably higher temperature melt sufficiently to
+flow. This phenomenon of melting through a long range of temperature may
+be due to the amorphous nature of the substance or to the fact that it
+consists of a very large number of components of many different melting
+points.
+
+The fats and oils of natural origin, that is, the animal and vegetable
+fats and oils, consist of mixtures of glycerides and, generally
+speaking, of a considerable number of such components. These components
+are crystalline and when separated in the pure state have definite
+melting points, although some exhibit the phenomenon of double melting
+point. For the most part the naturally occurring glycerides are mixed
+glycerides. In the natural fats and oils there are present also certain
+higher alcohols, of which cholesterol is characteristic of the animal
+fats and oils and phytosterol of many of the vegetable fats and oils. In
+addition to the crystalline glycerides and the higher alcohols present
+in neutral fats, there are in fats of lower grade, fatty acids, which
+are crystalline, and also various non-crystalline impurities of an
+unsaponifiable nature, and the presence of these impurities tends to
+lower the melting point. They also tend to induce undercooling and when
+the liquid fat or oil is being chilled for purposes of solidification or
+in determination of titer.
+
+The presence of water, especially when this is thoroughly mixed or
+emulsified with a fat or oil, also influences the melting point to a
+marked extent, causing the mixture to melt through a longer range of
+temperatures than would be the case if the water were absent. This is
+particularly true of emulsified fats and oils, such as butter and
+oleomargarine, both of which contain, besides water, the solids
+naturally present in milk or cream and including casein, milk sugar, and
+salts. The melting-point method recommended by the Committee is not
+applicable to such emulsions or other watery mixtures and the Committee
+has found it impossible to devise an accurate method for making
+softening-point or melting-point determinations on products of this
+nature. Not only the amount of water present but also the fineness of
+its particles, that is, its state of subdivision and distribution, in a
+fat or oil influences the softening point or melting point and causes it
+to vary widely in different samples.
+
+As a consequence of the foregoing facts, natural fats and oils do not
+exhibit a definite melting point, composed as they are of mixtures of
+various crystalline glycerides, higher alcohols, fatty acids, and
+non-crystalline substances. Therefore, the term melting point when
+applied to them requires further definition. They exhibit first a lower
+melting point (the melting point of the lowest melting component) or
+what might be called the softening point and following this the fat
+softens through a shorter or longer range of temperature to the final
+melting point at which temperature the fat is entirely liquid. This is
+the melting point determined by the Committee's melting-point method.
+The range between the softening point and the final melting point varies
+greatly with the different fats and oils depending on their chemical
+components, the water associated with them, emulsification, etc. In the
+case of coconut oil the range between softening point and final melting
+point is rather short; in the case of butter, long. Various methods have
+been devised to determine the so-called melting point of fats and oils.
+Most of these methods, however, determine, not the melting point, but
+the softening point or the flow point of the fat and the great
+difficulty has been in the past to devise a method which would determine
+even this point with reasonable accuracy and so that results could be
+easily duplicated. It has been the aim of the Committee to devise a
+simple method for the determination of the melting point of fats and
+oils, but it should be understood that the term melting point in the
+scientific sense is not applicable to natural fats and oils.
+
+FOOTNOTES:
+
+[22] Approved by the Supervisory Committee on Standard Methods of
+Analysis of the American Chemical Society.
+
+[23] Live steam must not be turned into tank cars or coils before
+samples are drawn, since there is no certain way of telling when coils
+are free from leaks.
+
+[24] If there is water present under the solid material this must be
+noted and estimated separately.
+
+[25] Boiling point of water at reduced pressures.
+
+ Pressure    Boiling Point   Boiling Point   Boiling Point
+  Mm. Hg.      to 1deg. C.        +15deg. C.           +20deg. C.
+   100           52deg. C.         67deg. C.            72deg. C.
+    90           50             65                70
+    80           47             62                67
+    70           45             60                65
+    60           42             57                62
+    50           38             53                58
+    40           34             49                54
+
+[26] Results comparable to those of the Standard Method may be obtained
+on most fats and oils by drying 5-g. portions of the sample, prepared
+and weighed as above, to constant weight in a well-constructed and
+well-ventilated air oven held uniformly at a temperature of 105deg. to
+110deg. C. The thermometer bulb should be close to the sample. The
+definition of constant weight is the same as for the Standard Method.
+
+[27] The following method is suggested by the Committee for routine
+control work: Weigh out 5- to 25-g. portions of prepared sample into a
+glass or aluminum (_Caution_: Aluminum soap may be formed) beaker or
+casserole and heat on a heavy asbestos board over burner or hot plate,
+taking care that the temperature of the sample does not go above 130deg. C.
+at any time. During the heating rotate the vessel gently on the board by
+hand to avoid sputtering or too rapid evolution of moisture. The proper
+length of time of heating is judged by absence of rising bubbles of
+steam, by the absence of foam or by other signs known to the operator.
+Avoid overheating of sample as indicated by smoking or darkening. Cool
+in desiccator and weigh.
+
+By co-operative work in several laboratories, the Committee has
+demonstrated that this method can be used and satisfactory results
+obtained on coconut oil even when a considerable percentage of free
+fatty acids is present, and the method is recommended for this purpose.
+Unfortunately on account of the very great personal factor involved, the
+Committee cannot establish this method as a preferred method.
+Nevertheless, after an operator has learned the technique of the method,
+it gives perfectly satisfactory results for ordinary oils and fats,
+butter, oleomargarine and coconut oil, and deserves more recognition
+than it has heretofore received.
+
+[28] For routine control work, filter paper is sometimes more convenient
+than the prepared Gooch crucible, but must be very carefully washed,
+especially around the rim, to remove the last traces of fat.
+
+[29] For routine work, an ash may be run on the original fat, and the
+soluble mineral matter obtained by deducting the ash on the insoluble
+impurities from this. In this case the Gooch crucible should be prepared
+with an ignited asbestos mat so that the impurities may be ashed
+directly after being weighed. In all cases ignition should be to
+constant weight so as to insure complete decomposition of carbonates.
+
+[30] See note on Soluble Mineral Matter following these methods. When
+the ash contains phosphates the factor 10 cannot be applied, but the
+bases consisting of calcium oxide, etc., must be determined, and the
+factor 10 applied to them.
+
+[31] For routine work methyl or denatured ethyl alcohol of approximately
+95 per cent strength may be used. With these reagents the end-point is
+not sharp.
+
+[32] P. C. McIlhiney, _J. Am. Chem. Soc._, 29 (1917), 1222, gives the
+following details for the preparation of the iodine monochloride
+solution:
+
+The preparation of the iodine monochloride solution presents no great
+difficulty, but it must be done with care and accuracy in order to
+obtain satisfactory results. There must be in the solution no sensible
+excess either of iodine or more particularly of chlorine, over that
+required to form the monochloride. This condition is most satisfactorily
+attained by dissolving in the whole of the acetic acid to be used the
+requisite quantity of iodine, using a gentle heat to assist the
+solution, if it is found necessary, setting aside a small portion of
+this solution, while pure and dry chlorine is passed into the remainder
+until the halogen content of the whole solution is doubled. Ordinarily
+it will be found that by passing the chlorine into the main part of the
+solution until the characteristic color of free iodine has just been
+discharged there will be a slight excess of chlorine which is corrected
+by the addition of the requisite amount of the unchlorinated portion
+until all free chlorine has been destroyed. A slight excess of iodine
+does little or no harm, but excess of chlorine must be avoided.
+
+[33] The melting point of oils may be determined in general according to
+the above procedure, taking into consideration the lower temperature
+required.
+
+
+
+
+PLANT AND MACHINERY
+
+Illustrations of machinery and layouts of the plant of a modern
+soap-making establishment.
+
+[Illustration: HOIST, LYE TANK, ETC.]
+
+[Illustration: MELTING-OUT TROUGH]
+
+[Illustration: LAUNDRY SOAP PLANT]
+
+[Illustration: DRYING RACK]
+
+[Illustration: SOAP KETTLE]
+
+[Illustration: REMELTER]
+
+[Illustration: CRUTCHER (Cross Section)]
+
+[Illustration: HORIZONTAL CRUTCHER]
+
+[Illustration: CRUTCHER]
+
+[Illustration: WRAPPING MACHINE (LAUNDRY SOAP)]
+
+[Illustration: SLABBER]
+
+[Illustration: CUTTING TABLE]
+
+[Illustration: AUTOMATIC POWER CUTTING TABLE]
+
+[Illustration: AUTOMATIC PRESS (LAUNDRY)]
+
+[Illustration: CUTTING TABLE (HAND)]
+
+[Illustration: CARTON WRAPPING MACHINE]
+
+[Illustration: DRYING RACKS]
+
+[Illustration: SOAP POWDER BOX]
+
+[Illustration: SCOURING SOAP PRESS]
+
+[Illustration: FRAME]
+
+[Illustration: SOAP POWDER EQUIPMENT]
+
+[Illustration: FLUFFY SOAP POWDER EQUIPMENT]
+
+[Illustration: SOAP POWDER MIXER]
+
+[Illustration: SOAP POWDER MILL]
+
+[Illustration: TOILET SOAP EQUIPMENT]
+
+[Illustration: TOILET SOAP DRYER]
+
+[Illustration: MILLING BOX]
+
+[Illustration: AMALGAMATOR]
+
+[Illustration: TOILET SOAP MILL]
+
+[Illustration: TOILET SOAP MILL]
+
+[Illustration: CHIPPER]
+
+[Illustration: PLODDER]
+
+[Illustration: HORIZONTAL CHIPPER]
+
+[Illustration: AMALGAMATOR (IMPROVED)]
+
+[Illustration: PRESS (LETTERING ON 4 SIDES OF CAKE)]
+
+[Illustration: Press (Foot)]
+
+[Illustration: Press (Foot)]
+
+[Illustration: PLODDER]
+
+[Illustration: AUTOMATIC PRESS (TOILET)]
+
+[Illustration: MULTIPLE CAKE CUTTER]
+
+[Illustration: CAKE CUTTER]
+
+[Illustration: CHIPPER]
+
+[Illustration: GLYCERINE DISTILLING PLANT]
+
+[Illustration: CRUDE GLYCERINE PLANT]
+
+[Illustration: H-A FATTY ACID DISTILLING PLANT]
+
+
+
+
+Appendix
+
+Tables marked * are taken from the German Year Book for Soap Industry.
+
+
+(U. S. BUREAU OF STANDARDS)
+
+THE METRIC SYSTEM.
+
+The fundamental unit of the metric system is the meter (the unit of
+length). From this the units of mass (gram) and capacity (liter) are
+derived. All other units are the decimal sub-divisions or multiples of
+these. These three units are simply related, so that for all practical
+purposes the volume of one kilogram of water (one liter) is equal to one
+cubic decimeter.
+
+
+============================================================
+                                        |
+Prefixes.       Meaning.                |     Units.
+________________________________________|___________________
+                                        |
+Milli- = one thousandth 1-1000     .001 |
+Centi- = one hundredth 1-100       .01  | Meter for length.
+Deci- = one tenth 1-10             .1   |
+Unit = one                        1.    | Gram for mass.
+Deka- = ten 10-1                 10.    |
+Hecto- = one hundred 100-1      100.    | Liter for capacity.
+Kilo- = one thousand 1000-1    1000.    |
+============================================================
+
+The metric terms are formed by combining the words "Meter," "Gram" and
+"Liter" with the six numerical prefixes.
+
+
+LENGTH
+
+10 milli-meters mm = 1 centi-meter                  c m
+
+10 centi-meters    = 1 deci-meter                   d m
+
+10 deci-meters     = 1 meter (about 40 inches)        m
+
+10 meters          = 1 deka-meter                 d k m
+
+10 deka-meters     = 1 hecto-meter                  h m
+
+10 hecto-meters    = 1 kilo-meter (about 5/8 mile)  k m
+
+
+MASS.
+
+10 milli-grams. m g = 1 centi-gram                   c g
+10 centi-grams      = 1 deci-gram                    d g
+10 deci-grams       = 1 gram (about 15 grains)         g
+10 grams            = 1 deka-gram                  d k g
+10 Deka-grams       = 1 hecto-gram                   h g
+10 hecto-grams      = 1 kilo-gram (about 2 pounds)   k g
+
+
+CAPACITY.
+
+10 milli-liters. m l = 1 centi-liter                    c l
+10 centi-liters      = 1 deci-liter                     d l
+10 deci-liters       = 1 liter (about 1 quart)            l
+10 liters            = 1 deka-liter                   d k l
+10 deka-liters       = 1 hecto-liter (about a barrel)   h l
+10 hecto-liters      = 1 kilo-liter                     k l
+
+The square and cubic units are the squares and cubes of the linear
+units.
+
+The ordinary unit of land area is the Hectare (about 2-1/2 acres).
+
+
+U.S. BUREAU OF STANDARDS TABLE OF METRIC EQUIVALENTS
+
+
+Meter = 39.37 inches.
+
+Legal Equivalent Adopted by Act of Congress July 28, 1866.
+
+
+LENGTH.
+
+Centimeter              = 0.3937 inch
+Meter                   = 3.28 feet
+Meter                   = 1.094 yards
+Kilometer               = 0.621 statute mile
+Kilometer               = 0.5396 nautical mile
+Inch                    = 2.540 centimeters
+Foot                    = 0.305 meter
+Yard                    = 0.914 meter
+Statute mile            = 1.61 kilometers
+Nautical mile           = 1.853 kilometers
+
+
+AREA.
+
+Sq. centimeter          = 0.155 sq. inch
+Sq. meter               = 10.76 sq. feet
+Sq. meter               = 1.196 sq. yards
+Hectare                 = 2.47 acres
+Sq. kilometer           = 0.386 sq. mile
+Sq. inch                = 6.45 sq. centimeters
+Sq. foot                = 0.0929 sq. meter
+Sq. yard                = 0.836 sq. meter
+Acre                    = 0.405 hectare
+Sq. mile                = 2.59 sq. kilometers
+
+
+WEIGHT.
+
+Gram                    = 15.43 grains
+Gram                    =  0.772 U. S. apoth. scruple
+Gram                    =  0.2572 U. S. apoth. dram
+Gram                    =  0.0353 avoir. ounce
+Gram                    =  0.03215 troy ounce
+Kilogram                =  2.205 avoir. pounds
+Kilogram                =  2.679 troy pounds
+Metric ton              =  0.984 gross or long ton
+Metric ton              =  1.102 short or net tons
+Grain                   =  0.064 gram
+U. S. apoth. scruple    =  1.296 grams
+U. S. apoth. dram       =  3.89 grams
+Avoir. ounce            = 28.35 grams
+Troy ounce              = 31.10 grams
+Avoir. pound            =  0.4536 kilogram
+Troy pound              =  0.373 kilogram
+Gross or long ton       =  1.016 metric tons
+Short or net ton        =  0.907 metric ton
+
+
+VOLUME.
+
+Cu. centimeter          =  0.0610 cu. inch
+Cu. meter               = 35.3 cu. feet
+Cu. meter               =  1.308 cu. yards
+Cu. inch                = 16.39 cu. centimeters
+Cu. foot                =  0.283 cu. meter
+Cu. yard                =  0.765 cu. meter
+
+
+CAPACITY.
+
+Millimeter             =  0.0338 U. S. liq. ounce
+Millimeter             =  0.2705 U. S. apoth. dram
+Liter                  =  1.057  U. S. liq. quarts
+Liter                  =  0.2642 U. S. liq. gallon
+Liter                  =  0.908  U. S. dry quart
+Dekaliter              =  1.135  U. S. pecks
+Hectoliter             =  2.838  U. S. bushels
+U. S. liq. ounce       = 29.57   millimeters
+U. S. apoth. dram      =  3.70   millimeters
+U. S. liq. quarts      =  0.946  liter
+U. S. dry quarts       =  1.101  liters
+U. S. liq. gallon      =  3.785  liters
+U. S. peck             =  0.881  dekaliter
+U. S. bushel           =  0.3524 hectoliter
+
+
+AVOIRDUPOIS WEIGHT.
+
+1 pound = 16 ounces = 256 drams
+           1 ounce  =  16   "
+
+
+TROY (APOTHECARIES') WEIGHT (U. S.)
+
+1 pound = 12 ounces = 96 drams = 288 scruples = 5,760 grains
+          1 ounce  =  8 drams =  24 scruples =   480 grains
+                       1 dram =   3 scruples =    60 grains
+                                  1 scruple  =    20 grains
+
+
+WINE (APOTHECARIES) LIQUID MEASURE (U. S.)
+
+1 gallon = 8 pints = 128 fl. ozs. = 1,024 fl. drams = 61,440 minims
+           1 pint  =  16 fl. ozs. =   128 fl. drams =  7,689 minims
+                       1 fl. oz.  =     8 fl. drams =    480 minims
+                                        1 fl. dram  =     60 minims
+
+_To find diameter of a circle_ multiply circumference by .31831.
+
+_To find circumference of a circle_, multiply diameter by 3.1416.
+
+_To find area of a circle_, multiply square of diameter by .7854.
+
+_To find surface of a ball_, multiply square of diameter by 3.1416.
+
+_To find side of an equal square_, multiply diameter by .8862.
+
+_To find cubic inches in a ball_, multiply cube of diameter by .5236.
+
+_Doubling the diameter of a pipe_, increases its capacity four times.
+
+_One cubic foot of anthracite coal_ weighs about 53 lbs.
+
+_One cubic foot of bituminous coal_ weighs from 47 to 50 pounds.
+
+_A gallon of water_ (U. S. standard) weighs 8-1/3 pounds and contains
+231 cubic inches.
+
+_A cubic foot of water_ contains 7-1/2 gallons, 1728 cubic inches and
+weighs 62-1/2 pounds.
+
+_To find the number of pounds of water a cylindrical_ tank contains,
+square the diameter, multiply by .785 and then by the height in feet.
+This gives the number of cubic feet which multiplied by 62-1/2 gives the
+capacity in pounds of water. Divide by 7-1/2 and this gives the capacity
+in gallons.
+
+_A horse-power_ is equivalent to raising 33,000 pounds 1 foot per
+minute, or 550 pounds 1 foot per second.
+
+_The friction of water in pipes_ is as the square of velocity. The
+capacity of pipes is as the square of their diameters; thus, doubling
+the diameter of a pipe increases its capacity four times.
+
+_To find the diameter of a pump cylinder_ to move a given quantity of
+water per minute (100 feet of piston being the standard of speed),
+divide the number of gallons by 4, then extract the square root, and the
+product will be the diameter in inches of the pump cylinder.
+
+_To find the horse-power necessary to elevate water_ to a given height,
+multiply the weight of the water elevated per minute in pounds by the
+height in feet, and divide the product by 33,000 (an allowance should be
+added for water friction, and a further allowance for loss in steam
+cylinder, say from 20 to 30 per cent).
+
+_To compute the capacity of pumping engines_, multiply the area of water
+piston, in inches, by the distance it travels, in inches, in a given
+time. Deduct 3 per cent for slip and rod displacement. The product
+divided by 231 gives the number of gallons in time named.
+
+_To find the velocity in feet per minute_ necessary to discharge a given
+volume of water in a given time, multiply the number of cubic feet of
+water by 144 and divide the product by the area of the pipe in inches.
+
+_To find the area of a required pipe_, the volume and velocity of water
+being given, multiply the number of cubic feet of water by 144 and
+divide the product by the velocity in feet per minute. The area being
+found, the diameter can be learned by using any table giving the "area
+of circles" and finding the nearest area, opposite to which will be
+found the diameter to correspond.
+
+
+Physical and Chemical Constants of Fixed Oils and Fats.
+
+(FROM LEWKOWITSCH AND OTHER AUTHORITIES.)
+
+______________________________________________________________________________
+                       |            |Specific  |             |               |
+                       | Specific   |gravity   |   Melting-  |Solidifying-   |
+                       | gravity    | at       |    point.   |    point.     |
+                       | at 15deg.C.|100deg.C. |     deg. C. |    deg. C.    |
+_______________________|____________|__________|_____________|_______________|
+                       |            |          |             |               |
+Linseed oil            | 0.931-0.938|  0.880   | -16 to -26  |      -16      |
+Hemp-seed oil          | 0.925-0.931|          |             |      -27      |
+Walnut oil             | 0.925-0.926|  0.871   |             |      -27      |
+Poppy-seed oil         | 0.924-0.927|  0.873   |             |      -18      |
+Sunflower oil          | 0.924-0.926|  0.919   |             |      -17      |
+Fir-seed oil           | 0.925-0.928|          |             |  -27 to -30   |
+Maize oil              | 0.921-0.926|          |             |  -10 to -15   |
+Cotton-seed oil        | 0.922-0.930|  0.867   |             |      12       |
+Sesame oil             | 0.923-0.924|  0.871   |             |      -5       |
+Rape-seed oil          | 0.914-0.917|  0.863   |             |  -2 to -10    |
+Black mustard oil      | 0.916-0.920|          |             |     -17.5     |
+Croton oil             | 0.942-0.955|          |             |      -16      |
+Castor oil             | 0.960-0.966|  0.910   |             |  -12 to -18   |
+Apricot-kernel oil     | 0.915-0.919|          |             |      -14      |
+Almond oil |           | 0.915-0.920|          |             |  -10 to -20   |
+Peanut (arachis) oil   | 0.916-0.920|  0.867   |             |   -3 to -7    |
+Olive oil              | 0.914-0.917|  0.862   |             |       2       |
+Menhaden oil           | 0.927-0.933|          |             |      -4       |
+Cod-liver oil          | 0.922-0.927|  0.874   |             |   0 to -10    |
+Seal oil               | 0.924-0.929|  0.873   |             |       3       |
+Whale oil              | 0.920-0.930|  0.872   |             |      -2       |
+Dolphin oil            | 0.917-0.918|          |             |   5 to -3     |
+Porpoise oil           |    0.926   |  0.871   |             |      -16      |
+Neat's-foot oil        | 0.914-0.916|  0.861   |             |   0 to 1.5    |
+Cotton-seed stearine   | 0.919-0.923|  0.867   |      40     |  31 to 32.5   |
+Palm oil               | 0.921-0.925|  0.856   |  27 to 42   |               |
+Cacao butter           | 0.950-0.952|  0.858   |  30 to 33   |   25 to 26    |
+Cocoa-nut oil          | 0.925-0.926|  0.873   |  20 to 26   |   16 to 20    |
+Myrtle wax             |    0.995   |  0.875   |  40 to 44   |   39 to 43    |
+Japan wax              | 0.970-0.980|  0.875   | 51 to 54.5  |      46       |
+Lard                   | 0.931-0.938|  0.861   |  41 to 46   |      29       |
+Bone fat               | 0.914-0.916|          |  21 to 22   |   15 to 17    |
+Tallow                 | 0.943-0.952|  0.860   |  42 to 46   |   35 to 37    |
+Butter fat             | 0.927-0.936|  0.866   | 29.5 to 33  |   19 to 20    |
+Oleomargarine          | 0.924-0.930|  0.859   |             |               |
+Sperm oil              | 0.875-0.884|  0.833   |             |      -25      |
+Bottle-nose oil        | 0.879-0.880|  0.827   |             |               |
+Carnauba wax           | 0.990-0.999|  0.842   |  84 to 85   |   80 to 81    |
+Wool-fat               |    0.973   |  0.901   |  39 to 42   |  30 to 30.2   |
+Beeswax                | 0.958-0.969|  0.822   |  62 to 64   |  60.5 to 62   |
+Spermaceti             |    0.960   |  0.812   | 43.5 to 49  | 43.4 to 44.2  |
+Chinese wax            |    0.970   |  0.810   | 80.5 to 81  |  80.5 to 81   |
+Tung (Chinese wood oil)| 0.936-0.942|          |             |   below -17   |
+Soya-bean oil          | 0.924-0.927|          |             |    8 to 15    |
+_______________________|____________|__________|_____________|_______________|
+
+
+Physical and Chemical Constants of Fixed Oils and Fats.
+
+(FROM LEWKOWITSCH AND OTHER AUTHORITIES.)
+
+Column Headings:
+A: Saponification value.
+B: Maumene test. (deg.)
+C: Iodine value.
+D: Hehner value.
+E: Reichert value.
+
+____________________________________________________________________________
+                   |             |           |            |         |      |
+                   |     [A]     |     [B]   |     [C]    |   [D]   | [E]  |
+___________________|_____________|___________|____________|_________|______|
+                   |             |           |            |         |      |
+Linseed oil        |   190-195   |  104-111  |   175-190  |         |      |
+Hemp-seed oil      |   190-193   |   95-96   |     148    |         |      |
+Walnut oil         |     195     |   96-101  |   144-147  |         |      |
+Poppy-seed oil     |     195     |   86-88   |   134-141  |  95.38  |      |
+Sunflower oil      |   193-194   |   72-75   |   120-129  |    95   |      |
+Fir-seed oil       |    191.3    |   98-99   | 118.9-120  |         |      |
+Maize oil          |   188-193   |  56-60.5  |  117-125   | 89-95.7 | 2.5  |
+Cotton-seed oil    |   191-195   |   68-77   |  104-110   |  96-17  |      |
+Sesame oil         |   189-193   |   64-68   |  105-109   |  95.8   | 0.35 |
+Rape-seed oil      |   170-178   |   51-60   |   95-105   |    95   |      |
+Black mustard oil  |  174-174.6  |   43-44   |   96-110   |  95.05  |      |
+Croton oil         | 210.3-215   |           | 101.7-104  |    89   | 13.5 |
+Castor oil         |   178-186   |   46-47   |  83.4-85.9 |         | 1.4  |
+Apricot-kernel oil | 192.2-193.1 |  42.5-46  |   100-107  |         |      |
+Almond oil         | 190.5-195.4 |   51-54   |    93-97   |  96.2   |      |
+Peanut (arachis)   |             |           |            |         |      |
+  oil              |   190-197   |   45-49   |    85-98   |  95.86  |      |
+Olive oil          |   191-196   | 41.5-45.5 |  80.6-84.5 |  95.43  | 0.3  |
+Menhaden oil       | 189.3-192   |  123-128  |   140-170  |         | 1.2  |
+Cod-liver oil      |   182-187   |  102-103  |   154-180  |  95.3   |      |
+Seal oil           |   190-196   |     92    |   127-140  |  94.2   | 0.22 |
+Whale-oil          |   188-193   |   91-92   |   110-136  |  93.5   | 2.04 |
+Dolphin  {Body oil |    197.3    |           |    99.5    |  93.07  | 5.6  |
+  oil    {Jaw oil  |     200     |           |    32.8    |  66.28  |65.92 |
+Porpoise {Body oil |   216-218.8 |     50    |   119.4    |         |23.45 |
+  oil    {Jaw oil  |    253.7    |           |    49.6    |  68.41  |65.8  |
+Neat's-foot oil    |    194.3    |  47-48.5  |  69.3-70.4 |         |      |
+Cotton-seed        |             |           |            |         |      |
+  stearine.        | 194.6-195.1 |     48    |  88.7-92.8 |  96.3   |      |
+Palm oil           | 196.3-202   |           |    53-57   |  95.6   | 0.5  |
+Cacao butter       | 192.2-193.5 |           |    32-41   |  94.59  | 1.6  |
+Cocoa-nut oil      |   250-253   |           |   8.5-9.3  |  88.6   | 3.7  |
+Myrtle wax         | 205.7-211.7 |           |     2.9    |         |      |
+Japan wax          |   220-222.4 |           |   4.2-8.5  |  90.6   |      |
+Lard               | 195.3-196.6 |   27-32   |    57-70   |   96    |      |
+Bone fat           |    190.9    |           |  46.3-49.6 |         |      |
+Tallow             |   195-198   |           |    36-47   |  95.6   | 0.25 |
+Butter fat         | 221.5-227   |           |    26-35   |  87.5   |28.78 |
+Oleomargarine      |   194-203.7 |           |   55.3-60  |  95-96  | 2.6  |
+Sperm oil          | 132.5-147   |   47-51   |     84     |         | 1.3  |
+Bottle-nose oil    |   126-134   |   41-47   |   77.4-82  |         | 1.4  |
+Carnauba wax       |    80-84    |           |    13.5    |         |      |
+Wool-fat           |  98.2-102.4 |           |    25-28   |         |      |
+Beeswax            |    91-96    |           |   8.3-11   |         |      |
+Spermaceti         |     128     |           |            |         |      |
+Chinese wax        |     63      |           |            |         |      |
+Tung (Chinese      |             |           |            |         |      |
+  wood oil)        |     193     |           |   150-165  |         |      |
+Soya-bean oil      | 190.6-192.9 |   59-61   | 121.3-124  |  95.5   |      |
+___________________|_____________|___________|____________|_________|______|
+
+
+*Temperature Correction Table for Hehner's Concentrated Bichromate
+Solution for Glycerine Analysis
+
+_____________________________________________
+               |                  |
+     A         |         f        |
+Temperature    | Corrected Volume | Logarithm
+               |       1 c.c.     |
+_______________|__________________|__________
+               |                  |
+   11deg. C    |    0.9980 ccm    |   99913
+   12deg. "    |    0.9985 "      |   99935
+   13deg. "    |    0.9990 "      |   99956
+   14deg. "    |    0.9995 "      |   99978
+   15deg. "    |    1.0000 "      |   00000
+   16deg. "    |    1.0005 "      |   00022
+   17deg. "    |    1.0010 "      |   00043
+   18deg. "    |    1.0015 "      |   00065
+   19deg. "    |    1.0020 "      |   00087
+   20deg. "    |    1.0025 "      |   00108
+   21deg. "    |    1.0030 "      |   00130
+   22deg. "    |    1.0035 "      |   00152
+   23deg. "    |    1.0040 "      |   00173
+_______________|__________________|__________
+
+
+*Table of Important Fatty Acids
+
+______________________________________________________________________________
+           |                   |      |                      |       |
+           |                   |      |     Boiling Point    |       |
+           |                   |      |______________________|       |Neutral-
+           |                   | Mol. |          |           | Melt- |ization
+   Name    |      Formula      | Wt.  | Ordinary |  100 mm   |  ing  |value
+           |                   |      | Pressure | Pressure  |   Pt. | Mg. KOH
+___________|___________________|______|__________|___________|_______|________
+           |                   |      |          |           |       |
+Butyric    | C_{4}H_{8}O_{2}   |  88  |  162.3   |           |       |637.5
+Caproic    | C_{6}H_{12}O_{2}  | 116  |  199.7   |           |       |483.6
+Caprylic   | C_{8}H_{16}O_{2}  | 144  | 236-237  |           | 16.5  |389.6
+Capric     | C_{10}H_{20}O_{2} | 172  | 268-270  | 199.5-200 | 31.3  |326.2
+Lauric     | C_{12}H_{24}O_{2} | 200  |          |    225    | 43.6  |280.5
+Myristic   | C_{14}H_{28}O_{2} | 228  |          |   250.5   | 53.8  |246.1
+Palmitic   | C_{16}H_{32}O_{2} | 256  |          |   268.5   |  62   |219.1
+Stearic    | C_{18}H_{36}O_{2} | 284  |          |    291    |  69.2 |197.5
+Arachidic  | C_{20}H_{40}O_{2} | 302  |          |           |  75   |185.8
+Behenic    | C_{22}H_{44}O_{2} | 330  |          |           | 77-78 |170.0
+Cerotic    | C_{27}H_{54}O_{2} | 400  |          |           |  78   |140.25
+Melissic   | C_{30}H_{60}O_{2} | 442  |          |           |  90   |126.5
+Oleic      | C_{18}H_{34}O_{2} | 282  |          | 185.5-286 |  14   |198.9
+Erucic     | C_{22}H_{42}O_{2} | 338  |          |           | 33-34 |165.9
+Linolic    | C_{18}H_{32}O_{2} | 280  |          |           |       |200.4
+Linolenic  | C_{18}H_{30}O_{2} | 278  |          |           |       |201.5
+Ricinoleic | C_{18}H_{34}O_{3} | 298  |          |           |       |181.6
+___________|___________________|______|__________|___________|_______|________
+
+
+*Comparison of Thermometer Scales
+
+n Degree Celsius = 4/5n Degree Reaumur = 32 + 9/5n Degree Fahrenheit
+
+n Degree Reaumur = 5/4n Degree Celsius = 32 + 9/4n Degree Fahrenheit
+
+n Degree Fahrenheit = 5/9 (n - 32) Degree Celsius = 4/9 (n - 32) Deg. R
+
+============================================================================
+ C.   R.     F.     |  C.  R.    F.    | C.  R.    F.     |  C.   R.     F.
+--------------------|------------------|------------------|-----------------
+-20  -16     -4     | 20  16     68    | 60  48    140    | 100   80    212
+-19  -15.2   -2.2   | 21  16.8   69.8  | 61  48.8  141.8  | 101   80.8 213.8
+-18  -14.4   -0.4   | 22  17.6   71.6  | 62  49.6  143.6  | 102   81.6 215.6
+-17  -13.6    1.4   | 23  18.4   73.4  | 63  50.4  145.4  | 103   82.4 217.4
+-16  -12.8    3.2   | 24  19.2   75.2  | 64  51.2  147.2  | 104   83.2 219.2
+                    |                  |                  |
+-15  -12      5     | 25  20     77    | 65  52    149    | 105   84    221
+-14  -11.2    6.8   | 26  20.8   78.8  | 66  52.8  150.8  | 106   84.8 222.8
+-13  -10.4    8.6   | 27  21.6   80.6  | 67  53.6  152.6  | 107   85.6 224.6
+-12   -9.6   10.4   | 28  22.4   82.4  | 68  54.4  154.4  | 108   86.4 226.4
+-11   -8.8   12.2   | 29  23.2   84.2  | 69  55.2  156.2  | 109   87.2 228.2
+                    |                  |                  |
+-10   -8     14     | 30  24     86    | 70  56    158    | 110   88    230
+ -9   -7.2   15.8   | 31  24.8   87.8  | 71  56.8  159.8  | 111   88.8 231.8
+ -8   -6.4   17.6   | 32  25.6   89.6  | 72  57.6  161.6  | 112   89.6 233.6
+ -7   -5.6   19.4   | 33  26.4   91.4  | 73  58.4  163.4  | 113   90.4 235.4
+ -6   -4.8   21.2   | 34  27.2   93.2  | 74  59.2  165.2  | 114   91.2 237.2
+                    |                  |                  |
+ -5   -4     23     | 35  28     95    | 75  60    167    | 115   92    239
+ -4   -3.2   24.8   | 36  28.8   96.8  | 76  60.8  168.8  | 116   92.8 240.8
+ -3   -2.4   26.6   | 37  29.6   98.6  | 77  61.6  170.6  | 117   93.6 242.6
+ -2   -1.6   28.4   | 38  30.4  100.4  | 78  62.4  172.4  | 118   94.4 244.4
+ -1   -0.8   30.2   | 39  31.2  102.2  | 79  63.2  174.2  | 119   95.2 246.2
+                    |                  |                  |
+  0    0     32     | 40  32    104    | 80  64    176    | 120   96    248
+  1    0.8   33.8   | 41  32.8  105.8  | 81  64.8  177.8  | 121   96.8 249.8
+  2    1.6   35.6   | 42  33.6  107.6  | 82  65.6  179.6  | 122   97.6 252.6
+  3    2.4   37.4   | 43  34.4  109.4  | 83  66.4  181.4  | 123   98.4 253.4
+  4    3.2   39.2   | 44  35.2  111.2  | 84  67.2  183.2  | 124   99.2 255.2
+                    |                  |                  |
+  5    4     41     | 45  36    113    | 85  68    185    | 125  100    257
+  6    4.8   42.8   | 46  36.8  114.8  | 86  68.8  186.8  | 126  100.8 258.8
+  7    5.6   44.6   | 47  37.6  116.6  | 87  69.6  188.6  | 127  101.6 260.6
+  8    6.4   46.4   | 48  38.4  118.4  | 88  70.4  190.4  | 128  102.4 262.4
+  9    7.2   48.2   | 49  39.2  120.2  | 89  71.2  192.2  | 129  103.2 264.2
+                    |                  |                  |
+ 10    8     50     | 50  40    122    | 90  72    194    | 130  104    266
+ 11    8.8   51.8   | 51  40.8  123.8  | 91  72.8  195.8  | 131  104.8 267.8
+ 12    9.6   53.6   | 52  41.6  125.6  | 92  73.6  197.6  | 132  105.6 269.6
+ 13   10.4   55.4   | 53  42.4  127.4  | 93  74.4  199.4  | 133  106.4 271.4
+ 14   11.2   57.2   | 54  43.2  129.2  | 94  75.2  201.2  | 134  107.2 273.2
+                    |                  |                  |
+ 15   12     59     | 55  44    131    | 95  76    203    | 135  108    275
+ 16   12.8   60.8   | 56  44.8  132.8  | 96  76.8  204.8  | 136  108.8 276.8
+ 17   13.6   62.6   | 57  45.6  134.6  | 97  77.6  206.6  | 137  109.6 278.6
+ 18   14.4   64.4   | 58  46.4  136.4  | 98  78.4  208.4  | 138  110.4 280.4
+ 19   15.2   66.2   | 59  47.2  138.2  | 99  79.2  210.2  | 139  111.2 282.2
+============================================================================
+
+
+*Quantities of Alkali Required for Saponification of Fats of Average
+Molecular Weight 670
+
+(Cocoanut Oil, Palmkernel Oil)
+
+_________________________________________________
+      |                     |                   |
+      |    Liters Alkali    |   Liters Alkali   |
+      |      Solution       |     Solution      |
+Kilos |     Sp. Gr. 1.1     |    Sp. Gr. 1.2    |
+______|_____________________|___________________|
+      |          |          |         |         |
+      |   NaOH   |    KOH   |   NaOH  |   KOH   |
+______|__________|__________|_________|_________|
+      |          |          |         |         |
+ 1000 |  1875.83 |  1902.99 |  844.67 |  930.35 |
+ 2000 |  3751.66 |  3805.97 | 1689.35 | 1860.70 |
+ 3000 |  5627.50 |  5708.96 | 2534.02 | 2791.04 |
+ 4000 |  7508.33 | 7611.94  | 3378.69 | 3721.39 |
+ 5000 |  9379.16 |  9514.93 | 4223.37 | 4651.74 |
+ 6000 | 11254.99 | 11417.91 | 5068.04 | 5582.09 |
+ 7000 | 13130.82 | 13320.90 | 5912.71 | 6512.44 |
+ 8000 | 15006.66 | 15223.88 | 6757.38 | 7442.78 |
+ 9000 | 16882.49 | 17126.87 | 7602.06 | 8373.13 |
+10000 | 18758.32 | 19029.85 | 8446.73 | 9303.48 |
+______|__________|__________|_________|_________|
+
+______________________________________________
+      |                   |
+      |   Liters Alkali   |  Liters Alkali
+      |     Solution      |    Solution
+Kilos |    Sp. Gr. 1.3    |  Sp. Gr. 1.355
+______|___________________|___________________
+      |         |         |         |
+      |   NaOH  |   KOH   |   NaOH  |   KOH
+______|_________|_________|_________|_________
+      |         |         |         |
+ 1000 |  510.27 |  622.71 |  409.61 |  517.97
+ 2000 | 1020.54 | 1245.41 |  819.21 | 1035.95
+ 3000 | 1530.81 | 1868.12 | 1228.82 | 1553.92
+ 4000 | 2041.01 | 2490.83 | 1638.43 | 2071.90
+ 5000 | 2551.35 | 3113.54 | 2048.04 | 2589.87
+ 6000 | 3061.61 | 3736.24 | 2457.65 | 3107.84
+ 7000 | 3571.88 | 4358.95 | 2867.26 | 3625.82
+ 8000 | 4082.15 | 4981.66 | 3276.86 | 4143.79
+ 9000 | 4592.42 | 5604.36 | 3886.47 | 4661.77
+10000 | 5102.69 | 6227.02 | 4096.08 | 5179.74
+______|_________|_________|_________|_________
+
+
+*Quantities of Alkali Required for Saponification of Fats of Average
+Molecular Weight 860
+
+(Tallow, Cottonseed Oil, Olive Oil, Etc.)
+
+_________________________________________________
+      |                     |                   |
+      |    Liters Alkali    |   Liters Alkali   |
+      |      Solution       |     Solution      |
+Kilos |     Sp. Gr. 1.1     |    Sp. Gr. 1.2    |
+______|_____________________|___________________|
+      |          |          |         |         |
+      |   NaOH   |    KOH   |   NaOH  |   KOH   |
+______|__________|__________|_________|_________|
+      |          |          |         |         |
+ 1000 |  1461.40 |  1482.56 |  658.05 |  724.81 |
+ 2000 |  2922.81 |  2965.12 | 1316.12 | 1449.61 |
+ 3000 |  4384.21 |  4447.67 | 1974.18 | 2174.42 |
+ 4000 |  5845.62 |  5930.23 | 2632.24 | 2899.22 |
+ 5000 |  7307.02 |  7412.79 | 3290.80 | 3624.03 |
+ 6000 |  8768.42 |  8895.85 | 3948.35 | 4348.84 |
+ 7000 | 10229.83 | 10377.91 | 4606.41 | 5073.64 |
+ 8000 | 11691.23 | 11860.45 | 5264.47 | 5798.45 |
+ 9000 | 13152.64 | 13343.02 | 5922.53 | 6523.25 |
+10000 | 14614.04 | 14825.58 | 6580.59 | 7248.06 |
+______|__________|__________|_________|_________|
+______________________________________________
+      |                   |
+      |   Liters Alkali   |  Liters Alkali
+      |     Solution      |    Solution
+Kilos |    Sp. Gr. 1.3    |  Sp. Gr. 1.355
+______|___________________|___________________
+      |         |         |         |
+      |   NaOH  |   KOH   |   NaOH  |   KOH
+______|_________|_________|_________|_________
+      |         |         |         |
+ 1000 |  397.54 |  485.13 |  319.11 |  403.54
+ 2000 |  795.07 |  970.27 |  638.23 |  807.08
+ 3000 | 1192.61 | 1455.40 |  957.34 | 1210.61
+ 4000 | 1590.14 | 1940.53 | 1276.45 | 1614.15
+ 5000 | 1987.68 | 2425.67 | 1595.57 | 2017.69
+ 6000 | 2385.21 | 2910.80 | 1914.68 | 2421.23
+ 7000 | 2782.75 | 3395.93 | 2233.79 | 2824.77
+ 8000 | 3180.28 | 3881.06 | 2552.90 | 3228.30
+ 9000 | 3577.82 | 4366.20 | 2872.02 | 3631.84
+10000 | 3975.35 | 4851.33 | 3191.13 | 4035.38
+______|_________|_________|_________|_________
+
+
+DENSITY AND STRENGTH OF SULPHURIC ACID (SIDERSKY).
+
+Column Headings:
+A: Degrees Twaddell
+B: Sp. Gr. at 15deg. C.
+C: % of pure acid (H_{2}SO_{4}).
+D: Equivalent (in cc.) of a kilo of pure acid.
+E: Equivalent (in cc.) of a liter of pure acid.
+
+
+=========================================
+
+ [A]    [B]     [C]      [D]        [E]
+_________________________________________
+
+1     1.007     1.9     52.620     96.930
+3     1.014     2.8     35.710     66.450
+4     1.022     3.8     25.650     47.230
+6     1.029     4.8     20.410     37.582
+8     1.037     5.8     16.670     30.690
+9     1.045     6.8     14.085     25.938
+10    1.052     7.8     12.198     22.460
+12    1.062     8.8     10.755     19.803
+13    1.067     9.8      9.524     17.540
+15    1.075    10.9      8.547     15.740
+17    1.083    11.9      7.752     14.278
+18    1.091    13.0      7.042     12.969
+20    1.100    14.1      6.452     11.882
+22    1.108    15.2      5.953     10.962
+23    1.116    16.2      5.526     10.177
+25    1.125    17.3      5.405      9.954
+27    1.134    18.5      4.76       8.770
+29    1.142    19.6      4.465      8.223
+30    1.152    20.8      4.184      7.723
+32    1.162    22.2      3.876      7.138
+34    1.171    23.3      3.663      6.745
+36    1.180    24.5      3.541      6.521
+38    1.190    25.8      3.258      5.999
+40    1.200    27.1      3.077      5.666
+42    1.210    28.4      2.907      5.353
+44    1.220    29.6      2.770      5.102
+46    1.231    31.0      2.618      4.865
+48    1.241    32.2      2.500      4.604
+50    1.252    33.4      2.392      4.406
+53    1.263    34.7      2.283      4.205
+55    1.274    36.0      2.179      4.012
+57    1.285    37.4      2.079      3.829
+60    1.297    38.8      1.988      3.661
+62    1.308    40.2      1.905      3.508
+64    1.320    41.6      1.821      3.354
+66    1.332    43.0      1.745      3.214
+69    1.345    44.4      1.665      3.085
+71    1.357    45.5      1.621      2.985
+74    1.370    46.9      1.558      2.869
+77    1.383    48.3      1.497      2.757
+80    1.397    49.8      1.436      2.646
+82    1.410    51.2      1.386      2.551
+85    1.424    52.6      1.335      2.459
+88    1.438    54.0      1.287      2.370
+91    1.453    55.4      1.237      2.270
+94    1.468    56.9      1.195      2.200
+97    1.483    58.3      1.156      2.130
+100   1.498    59.6      1.116      2.050
+103   1.514    61.0      1.080      1.980
+106   1.530    62.5      1.045      1.930
+108   1.540    64.0      1.010      1.860
+113   1.563    65.5      0.975      1.800
+116   1.580    67.0      0.950      1.740
+120   1.597    68.6      0.917      1.690
+123   1.615    70.0      0.888      1.630
+127   1.634    71.6      0.855      1.570
+130   1.652    73.2      0.845      1.520
+134   1.671    74.7      0.800      1.470
+138   1.691    76.4      0.774      1.430
+142   1.711    78.1      0.749      1.390
+146   1.732    79.9      0.722      1.320
+151   1.753    81.7      0.705      1.280
+155   1.774    84.1      0.672      1.235
+160   1.798    86.5      0.639      1.190
+164   1.819    89.7      0.609      1.120
+168   1.842   100.0      0.544      1.000
+
+
+*Densities of Potassium Carbonate Solutions at 15 C (Gerlach)
+
+=======================
+        |             |
+        |  Per cent   |
+Sp. Gr. |   of pure   |
+        | K_{2}CO_{3} |
+________|_____________|
+        |             |
+1.00914 |    1        |
+1.01829 |    2        |
+1.02743 |    3        |
+1.03658 |    4        |
+1.04572 |    5        |
+1.05513 |    6        |
+1.06454 |    7        |
+1.07396 |    8        |
+1.08337 |    9        |
+1.09278 |   10        |
+1.10258 |   11        |
+1.11238 |   12        |
+1.12219 |   13        |
+1.13199 |   14        |
+1.14179 |   15        |
+1.15200 |   16        |
+1.16222 |   17        |
+1.17243 |   18        |
+1.18265 |   19        |
+1.19286 |   20        |
+1.20344 |   21        |
+1.21402 |   22        |
+1.22459 |   23        |
+1.23517 |   24        |
+1.24575 |   25        |
+1.25681 |   26        |
+1.26787 |   27        |
+1.27893 |   28        |
+1.28999 |   29        |
+1.30105 |   30        |
+1.31261 |   31        |
+1.32417 |   32        |
+1.33573 |   33        |
+1.34729 |   34        |
+1.35885 |   35        |
+1.37082 |   36        |
+1.38279 |   37        |
+1.39476 |   38        |
+1.40673 |   39        |
+1.41870 |   40        |
+1.43104 |   41        |
+1.44338 |   42        |
+1.45573 |   43        |
+1.46807 |   44        |
+1.48041 |   45        |
+1.49314 |   46        |
+1.50588 |   47        |
+1.51861 |   48        |
+1.53135 |   49        |
+1.54408 |   50        |
+1.55728 |   51        |
+1.57048 |   52        |
+1.57079 |   53.024    |
+________|_____________|
+
+
+*Constants of Certain Fatty Acids and Triglycerides
+
+=========================================================
+              |          |            |
+              |          |            |  Per cent Yield
+Triglycerides | Mol. Wt. | Mol. Wt.   |__________________
+      of      | of Fatty | of Tri-    |       |
+              | of Fatty | glycerides | Fatty | Glycerine
+              |          |            | Acid  |
+______________|__________|____________|_______|___________
+              |          |            |       |
+Stearic Acid  |    284   |     890    | 95.73 |  10.34
+Oleic Acid    |    282   |     884    | 95.70 |  10.41
+Margaric Acid |    270   |     848    | 95.52 |  10.85
+Palmitic Acid |    256   |     806    | 95.28 |  11.42
+Myristic Acid |    228   |     722    | 94.47 |  12.74
+Lauric Acid   |    200   |     638    | 94.04 |  14.42
+Capric Acid   |    172   |     594    | 93.14 |  15.48
+Caproic Acid  |    116   |     386    | 90.16 |  23.83
+Butyric Acid  |     88   |     302    | 87.41 |  30.46
+______________|__________|____________|_______|___________
+
+
+PERCENTAGES OF SOLID CAUSTIC SODA AND CAUSTIC POTASH IN CAUSTIC LYES
+ACCORDING TO BAUME SCALE.
+
+Degrees    %     %
+ Baume.  NaOH   KOH
+
+ 1       0.61   0.90
+ 2       0.93   1.70
+ 3       2.00   2.60
+ 4       2.71   3.50
+ 5       3.35   4.50
+ 6       4.00   5.60
+ 7       4.556  6.286
+ 8       5.29   7.40
+ 9       5.87   8.20
+10       6.55   9.20
+11       7.31  10.10
+12       8.00  10.90
+13       8.68  12.00
+14       9.42  12.90
+15      10.06  13.80
+16      10.97  14.80
+17      11.84  15.70
+18      12.64  16.50
+19      13.55  17.60
+20      14.37  18.60
+21      15.13  19.50
+22      15.91  20.50
+23      16.77  21.40
+24      17.67  22.50
+25      18.58  23.30
+26      19.58  24.20
+27      20.59  25.10
+28      21.42  26.10
+29      22.64  27.00
+30      23.67  28.00
+31      24.81  28.90
+32      25.80  29.80
+33      26.83  30.70
+34      27.80  31.80
+35      28.83  32.70
+36      29.93  33.70
+37      31.22  34.90
+38      32.47  35.90
+39      33.69  36.90
+40      34.96  37.80
+41      36.25  38.90
+42      37.53  39.90
+43      38.80  40.90
+44      39.99  42.10
+45      41.41  43.40
+46      42.83  44.60
+47      44.38  45.80
+48      46.15  47.10
+49      47.58  48.25
+50      49.02  49.40
+
+
+GLYCERINE CONTENT OF MORE COMMON OILS AND FATS USED IN SOAP MAKING.
+
+   Kind.          Theoretical     Average Free     % Pure        Yield
+                 Yield of Pure   Fatty Acid in    Glycerine     Soap Lye
+                 Glycerine of      Commercial   in Commercial   80% Crude
+                  Neutral Oil        Oil.            Oil.       Glycerine.
+                    or Fat.
+
+Beef Tallow           10.7             5           10.2         12.75
+Bone Grease           10.5            20-50         5.2- 8.4     6.5-10.5
+Castor Oil             9.8           0.5-10         8.8- 9.8    11.0-12.45
+Cocoanut Oil          13.9             3-5         13.2-13.5    16.5-16.9
+Cocoanut Oil Off                      15-40         8.3-11.8    10.37-14.75
+Corn Oil              10.4             1-10         9.3-10.3    11.62-12.9
+Cottonseed Oil        10.6            Trace        10.6         13.25
+Hog Grease            10.6           0.5-1         10.5-10.6    13.12-13.25
+Horse Grease          10.6             1-3         10.5-10.6    13.12-13.25
+Olive Oil             10.3             2-25         7.7-10.2     9.62-12.75
+Olive Foots                           30-60           4-7           5-8.75
+Palm Oil              11.0            10-50         5.5-10       6.87-12.5
+Palmkernel Oil        13.3             4-8         12.2-12.8    15.25-16
+Peanut Oil            10.4             5-20         8.3-9.9     10.37-12.37
+Soya Bean Oil         10.4             2           10.2         12.75
+Train Oil             10.0             2-20           8-9.8     10.0-12.25
+Vegetable Tallow      10.9             1-3         10.5-10.8    13.12-13.5
+
+
+*Table of Specific Gravities of Pure Commercial Glycerine with
+Corresponding Percentage of Water. Temperature 15 C.
+
+------------------+------------------
+ Sp. Gr.  % Water | Sp. Gr.  % Water
+  1.262      0    |  1.160      38
+  1.261      1    |  1.157      39
+  1.258      2    |  1.155      40
+  1.255      3    |  1.152      41
+  1.2515     4    |  1.149      42
+  1.250      5    |  1.1464     43
+  1.2467     6    |  1.1437     44
+  1.2450     7    |  1.141      45
+  1.243      8    |  1.1377     46
+  1.241      9    |  1.1353     47
+  1.237     10    |  1.1326     48
+  1.235     11    |  1.1304     49
+  1.2324    12    |  1.127      50
+  1.229     13    |  1.125      51
+  1.2265    14    |  1.1224     52
+  1.2245    15    |  1.1204     53
+  1.2225    16    |  1.117      54
+  1.2185    17    |  1.114      55
+  1.2174    18    |  1.112      56
+  1.2142    19    |  1.109      57
+  1.211     20    |  1.106      58
+  1.207     21    |  1.103      59
+  1.203     22    |  1.1006     60
+  1.2004    23    |  1.088      65
+  1.198     24    |  1.075      70
+  1.195     25    |  1.0623     75
+  1.1923    26    |  1.049      80
+  1.189     27    |  1.0365     85
+  1.188     28    |  1.0243     90
+  1.1846    29    |  1.0218     91
+  1.182     30    |  1.0192     92
+  1.179     31    |  1.0168     93
+  1.176     32    |  1.0147     94
+  1.1734   33     |  1.0125     95
+  1.171    34     |  1.01       96
+  1.168    35     |  1.0074     97
+  1.165    36     |  1.0053     98
+  1.163    37     |  1.0026     99
+------------------+------------------
+
+
+Table of Percentage, Specific Gravity and Beaume Degree of Pure
+Glycerine Solutions
+
+=========+===========+===========++=========+===========+===========
+Per cent |Sp. Gr.    |Degree     ||Per cent |Sp. Gr.    |Degree
+Water    |Champion   |Beaume     ||Water    |Champion   |Beaume
+         |and Pellet |(Berthelot)||         |and Pellet |(Berthelot)
+=========+===========+===========++=========+===========+===========
+     0   |    1.2640 |      31.2 ||    11.0 |    1.2350 |      28.6
+     0.5 |    1.2625 |      31.0 ||    11.5 |    1.2335 |      28.4
+     1.0 |    1.2612 |      30.9 ||    12.0 |    1.2322 |      28.3
+     1.5 |    1.2600 |      30.8 ||    12.5 |    1.2307 |      28.2
+     2.0 |    1.2585 |      30.7 ||    13.0 |    1.2295 |      28.0
+     2.5 |    1.2575 |      30.6 ||    13.5 |    1.2280 |      27.8
+     3.0 |    1.2560 |      30.4 ||    14.0 |    1.2270 |      27.7
+     3.5 |    1.2545 |      30.3 ||    14.5 |    1.2255 |      27.6
+     4.0 |    1.2532 |      30.2 ||    15.0 |    1.2242 |      27.4
+     4.5 |    1.2520 |      30.1 ||    15.5 |    1.2230 |      27.3
+     5.0 |    1.2505 |      30.0 ||    16.0 |    1.2217 |      27.2
+     5.5 |    1.2490 |      29.9 ||    16.5 |    1.2202 |      27.0
+     6.0 |    1.2480 |      29.8 ||    17.0 |    1.2190 |      26.9
+     6.5 |    1.2465 |      29.7 ||    17.5 |    1.2177 |      26.8
+     7.0 |    1.2455 |      29.6 ||    18.0 |    1.2165 |      26.7
+     7.5 |    1.2440 |      29.5 ||    18.5 |    1.2150 |      26.5
+     8.0 |    1.2427 |      29.3 ||    19.0 |    1.2137 |      26.4
+     8.5 |    1.2412 |      29.2 ||    19.5 |    1.2125 |      26.3
+     9.0 |    1.2400 |      29.0 ||    20.0 |    1.2112 |      26.2
+     9.5 |    1.2390 |      28.9 ||    20.5 |    1.2100 |      26.0
+    10.0 |    1.2375 |      28.8 ||    21.0 |    1.2085 |      25.0
+    10.5 |    1.2362 |      28.7 ||         |           |
+=========+===========+===========++=========+===========+===========
+
+
+*Table of Specific Gravities of Pure Glycerine Solutions with
+Corresponding Beaume Degree and Percent Water
+
+--------+--------+-------+---------+--------+--------
+Per cent| Sp. Gr.| Degree| Percent | Sp. Gr.| Degree
+Water   |        | Beaume|  Water  |        | Beaume
+--------+--------+-------+---------+--------+--------
+        |        |       |         |        |
+  0.0   | 1.2640 |  31.2 |    1.0  | 1.2612 |  30.9
+  0.5   | 1.2625 |  31.0 |    1.5  | 1.2600 |  30.8
+  2.0   | 1.2585 |  30.7 |   12.0  | 1.2322 |  28.3
+  2.5   | 1.2575 |  30.6 |   12.5  | 1.2307 |  28.2
+  3.0   | 1.2560 |  30.4 |   13.0  | 1.2295 |  28.0
+  3.5   | 1.2545 |  30.3 |   13.5  | 1.2280 |  27.8
+  4.0   | 1.2532 |  30.2 |   14.0  | 1.2270 |  27.7
+  4.5   | 1.2520 |  30.1 |   14.5  | 1.2255 |  27.6
+  5.0   | 1.2505 |  30.0 |   15.0  | 1.2242 |  27.4
+  5.5   | 1.2490 |  29.9 |   15.5  | 1.2230 |  27.3
+  6.0   | 1.2480 |  29.8 |   16.0  | 1.2217 |  27.2
+  6.5   | 1.2465 |  29.7 |   16.5  | 1.2202 |  27.0
+  7.0   | 1.2455 |  29.6 |   17.0  | 1.2190 |  26.9
+  7.5   | 1.2440 |  29.5 |   17.5  | 1.2177 |  26.8
+  8.0   | 1.2427 |  29.3 |   18.0  | 1.2165 |  26.7
+  8.5   | 1.2412 |  29.2 |   18.5  | 1.2150 |  26.5
+  9.0   | 1.2400 |  29.0 |   19.0  | 1.2137 |  26.4
+  9.5   | 1.2390 |  28.9 |   19.5  | 1.2125 |  26.3
+ 10.0   | 1.2375 |  28.8 |   20.0  | 1.2112 |  26.2
+ 10.5   | 1.2362 |  28.7 |   20.5  | 1.2100 |  26.0
+ 11.0   | 1.2350 |  28.6 |   21.0  | 1.2085 |  25.9
+ 11.5   | 1.2335 |  28.4 |         |        |
+--------+--------+-------+---------+--------+--------
+
+
+
+
+INDEX
+
+
+A
+
+Acetin process for the determination of glycerol, 155.
+
+Acid, Clupanodonic, 20.
+
+Acid, Hydrochloric, 111.
+
+Acid, Lauric, 2.
+
+Acid, Myristic, 2.
+
+Acid, Napthenic, 24.
+
+Acid, Oleic, 15, 19.
+
+Acid, Palmitic, 2.
+
+Acid, Pinic, 22.
+
+Acid, Resin, 144.
+
+Acid, Stearic, 15, 19.
+
+Acid, Sulfuric, 112.
+
+Acid, Sylvic, 22.
+
+Acid saponification, 120.
+
+Air bleaching of palm oil, 12.
+
+Albuminous matter, Removal from tallow, 6.
+
+Alcohol, Denatured, 82.
+
+Alcoholic method for free alkali in soap, 139.
+
+Alkali Blue 6 B, indicator, 129.
+
+Alkali, Total, determination of in soap, 147.
+
+Alkalis, 25.
+
+Alkalis used in soap making,
+  Testing of, 134.
+
+Amalgamator, 33.
+
+Analysis, Glycerine, International, 150.
+
+Analysis, Soap, 137.
+
+Analysis, Standard methods for fats and oils, 165-196.
+
+Aqueous saponification, 121.
+
+Arachis oil, 79.
+
+Autoclave saponification, 118.
+
+Automobile soaps, 41.
+
+
+B
+
+Barrels, sampling, 168.
+
+Baume scale, 25.
+
+Bayberry wax, Use in shaving soap, 89.
+
+Bichromate Process for glycerol determination, 160.
+
+Bleaching, Fullers' earth process for tallow, 4.
+
+Bleaching palm oil by bichromate method, 9.
+
+Bleaching palm oil by air, 12.
+
+Bosshard & Huggenberg method for determination of free alkali, 140.
+
+Bunching of soap, 52.
+
+
+C
+
+Candelite, 96.
+
+Candle tar, 125.
+
+Carbolic soap, 77.
+
+Carbon Dioxide, Formation of in carbonate saponification, 45.
+
+Carbonate, potassium, 29.
+
+Carbonate, saponification, 35, 45.
+
+Carbonate, sodium, 28.
+
+Castile soap, 79.
+
+Castor oil ferment, 121.
+
+Castor oil, Use of in transparent soaps, 83.
+
+Caustic potash, 26.
+
+Caustic potash, Electrolytic, 27.
+
+Caustic soda, 26.
+
+Changes in soap-making, 36.
+
+Chemist, Importance of, 127.
+
+Chipper, Soap, 32.
+
+Chip soap, 54.
+
+Chip soap, Cold made, 55.
+
+Chip soap, Unfilled, 56.
+
+Chrome bleaching of palm oil, 9.
+
+Cloud test for oil, Standard method, 182-183.
+
+Clupanodonic acid, 20.
+
+Cocoanut oil, 6.
+
+Cold cream soap, 78.
+
+Cold made chip soaps, 55.
+
+Cold made toilet soaps, 72.
+
+Cold made transparent soaps, 84.
+
+Cold process, 35, 43.
+
+Colophony, 22.
+
+Coloring soap, 75.
+
+Copra, 7.
+
+Corn oil, 14.
+
+Corrosive sublimate, 78.
+
+Cotton goods. Soaps used for, 103.
+
+Cottonseed oil, 14.
+
+Cream, Shaving, 90.
+
+Crude glycerine, 113.
+
+Crutcher, 32.
+
+Curd soap, 71.
+
+Cutting table, 32.
+
+
+D
+
+Determination of free fatty acid, 128.
+
+Determination of unsaponifiable matter, 132.
+
+Distillation of fatty acids, 125.
+
+Drying machine, 32.
+
+
+E
+
+Enzymes, 17.
+
+Eschweger soap, 81.
+
+Examination of fats and oils, 128.
+
+
+F
+
+Fahrion's method for moisture, 138.
+
+Fats and oils, Examination of, 128.
+
+Fats and oils used in soap manufacture, 3.
+
+Fatty acids, 14.
+
+Fatty acids, Distillation of, 125.
+
+Ferments, Splitting fats with, 121.
+
+Fillers for laundry soaps, 53.
+
+Fillers for soap powders, 58.
+
+Finishing change, 36.
+
+Fish oils, 20.
+
+Floating soap, 62.
+
+Formaldehyde soap, 78.
+
+Frames, 31.
+
+Free alkali in soap, Determination of, 139.
+
+Free fatty acid, Determination of, 128.
+
+Free fatty acids, Extraction from tallow, 6.
+
+Free fatty acid, Standard method of dilu., 174.
+  Note on method, 188-189.
+
+Full boiled soaps, 35.
+
+Fullers' earth bleaching of tallow, 4.
+
+
+G
+
+Glycerides, 2.
+
+Glycerine, 2.
+
+Glycerine analysis, 150.
+
+Glycerine change, 36.
+
+Glycerine, Crude, 113.
+
+Glycerine in spent lyes, Recovery of, 106.
+
+Glycerine in soap, Determination of, 149.
+
+Glycerine, Sampling crude, 162.
+
+Glycerine soaps, 83.
+
+Glycerol content, Ways of calculating actual, 159.
+
+Glycerol determination, Acetin process, 155.
+
+Glycerol determination, Bichromate process for, 160.
+
+Graining soap, 30.
+
+Grease, 21.
+
+Grease, Bleaching, 21.
+
+Grinding soap, 34.
+
+
+H
+
+Hand Paste, 93.
+
+Hard water, 29.
+
+Hardened oils in toilet soap, Use of, 96.
+
+Hydrocarbon oils, 2.
+
+Hydrogenating oils, 19.
+
+Hydrolysis of fats and oils, 17.
+
+Hydrolytic dissociation of soap, 1.
+
+Hydrometers, 25.
+
+
+I
+
+Indicators, Action, 135-6.
+
+Insoluble impurities in fatty oils, Determination of
+  (standard method), 172.
+    Note on method, 187.
+
+Insoluble matter in soap, determination of, 143.
+
+International committee on glycerine analysis, 150.
+
+Iodine manufacturing oil, 191.
+
+Iodine member Wijs method, Standard, 177-181.
+  Note on method, 191.
+
+Iodine soap, 78.
+
+
+J
+
+Joslin, ref., 113.
+
+
+K
+
+"Killing" change, 36.
+
+Koettstorfer number (Standard method), 181-182.
+
+Kontakt reagent, 117.
+
+Krebitz Process, 123.
+
+Krutolin, 96.
+
+
+L
+
+Leiste & Stiepel method for rosin in soap, 146.
+
+Liebermann, Storch reaction, 144.
+
+Light powders, 60.
+
+Laundry soap, 48.
+
+LeBlanc Process, 28.
+
+Lewkowitsch, ref., 17, 146.
+
+Lime saponification, 118.
+
+Lime, Use in Krebitz Process, 123.
+
+Lime, Use in treatment of glycerine water, 116.
+
+Liquid medicinal soaps, 79.
+
+Liquid soaps, 94.
+
+Lyes, Spent, 37.
+
+
+M
+
+Magnesia, Use in  autoclave saponification, 120.
+
+Manganese sulfate,
+  Use of as catalyzer in fermentative cleavage of fats, 122.
+
+Marine soaps, 39.
+
+Medicinal soaps, 76.
+
+Medicinal soaps, Less important, 78.
+
+Medicinal soaps, Therapeutic value of, 76.
+
+Melting point of fat or oil, Standard method, 193.
+
+Mercury soaps, 78.
+
+Metallic soaps, 1.
+
+Methyl orange, indicator, 136.
+
+Meyerheim, ref., 21.
+
+Mill soap, 32.
+
+Moisture in soap, Determination of, 138, 130.
+
+Moisture and volatile matter in fats and oils, Standard method for
+  detm. of, 170.
+    Note on method, 184-185.
+
+Mottle in soap, 81.
+
+Mug shaving soap, 90.
+
+
+N
+
+Naphtha, Incorporation in soap, 49.
+
+Naphthenic acids, 24.
+
+Nigre, 36.
+
+Normal acids, Equivalent in alkalis, 136.
+
+
+O
+
+Oils and fats, 1.
+
+Oils and fats, Chemical constants, 18.
+
+Oils and fats, Distinction, 1.
+
+Oils and fats, Preserving, 18.
+
+Oils and fat, Nature of used in soap manufacture, 2.
+
+Oils and fats, Rancidity of, 16.
+
+Oil hardening, 19.
+
+Oleic acid, 15, 19.
+
+Olein, 2, 19.
+
+Olive oil, 14.
+
+Olive oil foots, 14.
+
+Organoleptic methods, 127.
+
+
+P
+
+Palmatin, 2.
+
+Palm kernel oil, 8.
+
+Palmitic acid, 2.
+
+Palm oil, 8.
+
+Palm oil, air bleaching, 12.
+
+Palm oil, Chrome bleaching of, 9.
+
+Palm oil soap, 66.
+
+Pearl ash, 29.
+
+Perfuming and coloring toilet soaps, 73.
+
+Peroxide soap, 78.
+
+Petroff reagent, 117.
+
+Pfeilring reagent, 117.
+
+Phenol, 77.
+
+Phenolphthalein, indicator, 38.
+
+Phenolphthalein, Using as indicator, 51.
+
+Phenols, Soaps containing, 77.
+
+Pinic acid, 22.
+
+Plodder, 33.
+
+Potash from wood ash, 27.
+
+Potassium carbonate, 29.
+
+Powders, Light, 60.
+
+Powders, Scouring, 61.
+
+Powders, Shaving, 90.
+
+Powders, Soap, 56.
+
+Precipitation test for treated spent lyes, 110.
+
+Prevention of rancidity, 18.
+
+Pumice or sand soaps, 93.
+
+Purple shade in soap, 75.
+
+
+R
+
+Rancidity of oils and fats, 16.
+
+Rancidity, Prevention, 18.
+
+Recovery of glycerine from spent lye, 106.
+
+Red oil, 15.
+
+Red oil, Saponified, 15.
+
+Resin acids, Total fatty and, Determination of in soap, 144.
+
+Ribot, ref., 20.
+
+Rosin, 22.
+
+Rosin, Determination of in soap, 144.
+
+Rosin saponification, 23.
+
+Run and glued up soaps, 69.
+
+Run soaps, 39.
+
+
+S
+
+Sal soda, 29.
+
+Salt, 30.
+
+Salting out, 30.
+
+Salt "pickle," 37.
+
+Sampling crude glycerine, 162.
+
+Sampling for standard method, 166.
+  Note on, 184.
+
+Sampling oils and fats, 128.
+
+Sampling soap, 137.
+
+Saponification by ferments, 121.
+
+Saponification, Acid, 120.
+
+Saponification, Aqueous, 121.
+
+Saponification, Autoclave, 118.
+
+Saponification, Carbonate, 45.
+
+Saponification defined, 2, 105.
+
+Saponification, Lime, 118.
+
+Saponification number, 181-182.
+
+Saponification, Rosin, 23.
+
+Saponification, Various methods, 105.
+
+Scouring and fulling soaps for wool, 98.
+
+Scouring powders, 61.
+
+Scouring soap, 61.
+
+Semi-boiled laundry soaps, 49.
+
+Semi-boiled process, 44.
+
+Shaving cream, 90.
+
+Shaving powder, 90.
+
+Shaving soaps, 87.
+
+Silica and silicates, Determination of in soap, 148.
+
+Silk dyeing, 102.
+
+Silk industry, Soaps used in, 101.
+
+Slabber, 32.
+
+Smith method for moisture in soap, 138.
+
+Soap analysis, 137.
+
+Soap, Automobile, 41.
+
+Soap, Carbolic, 71.
+
+Soap, Castile, 79.
+
+Soap, Chip, 54.
+
+Soap Chip, cold made, 55.
+
+Soap, Chip, unfilled, 56.
+
+Soap, Cold cream, 78.
+
+Soap, Coloring, 75.
+
+Soap containing phenols, 77.
+
+Soap, Curd, 71.
+
+Soap, Defined, 1.
+
+Soap, Determination insoluble matter, 143.
+
+Soap, Determining glycerine in, 149.
+
+Soap, Eschweger, 81.
+
+Soap, Floating, 62.
+
+Soap, Formaldehyde, 78.
+
+Soap for wool, Scouring and fulling, 98.
+
+Soap, Full boiled, 35.
+
+Soap, Iodine, 78.
+
+Soap kettle, 31.
+
+Soap, Laundry, 48.
+
+Soap, Liquid, 94.
+
+Soap lye crude glycerine, 113.
+
+Soap, Marine, 39.
+
+Soap, Medicinal, 76.
+
+Soap, Medicinal, less important, 78.
+
+Soap, Mercury, 78.
+
+Soap, Metallic, 1.
+
+Soap, Peroxide, 78.
+
+Soap powders, 56.
+
+Soap, Pumice or sand, 93.
+
+Soap, Rosin settled, 50.
+
+Soap, Run and glued up, 69.
+
+Soap, Scouring, 61.
+
+Soap, Semi-boiled laundry, 49.
+
+Soap, Shaving, 87.
+
+Soap, Sulphur, 77.
+
+Soap, Tannin, 78.
+
+Soap, Tar, 77.
+
+Soap, Test for color of, 133.
+
+Soap, Textile, 98.
+
+Soap, Toilet, 65.
+
+Soap, Toilet cheaper, 68.
+
+Soap, Toilet, cold made, 72.
+
+Soap, Toilet perfuming and coloring, 73.
+
+Soap, Transparent, 82.
+
+Soap, Transparent, cold made, 84.
+
+Soap used for cotton goods, 103.
+
+Soap used in the silk industry, 101.
+
+Soap, Witch hazel, 78.
+
+Soap, Wool thrower's, 100.
+
+Soap, Worsted finishing, 101.
+
+Soda ash, 28.
+
+Sodium carbonate, 28.
+
+Sodium perborate, Use of in soap powders, 57.
+
+Soft soaps, 40.
+
+Soluble mineral matter detm. of in fats and oils, 173.
+  Note on method, 187-188.
+
+Solvay process, 28.
+
+Soya bean oil, 14.
+
+Spent lye, Recovery of glycerine from, 106.
+
+Spent lyes, 37.
+
+Spent lyes, Treatment of for glycerine recovery, 107.
+
+Splitting fats with ferments, 121.
+
+Standard methods of analysis for fats and oils, 165-196.
+
+Starch and gelatine, Determination in soap, 143.
+
+Stearic acid, 15, 19.
+
+Stearin, 2, 19.
+
+Strengthening change, 36.
+
+Strengthening lyes, 38.
+
+Strunz crutcher, 63.
+
+Sugar in soap, Determination of, 150.
+
+Sugar, Use in transparent soap, 83.
+
+Sulfate of alumina, Use of in spent lyes, 108.
+
+Sulphonated oils, 104.
+
+Sulphur soaps, 77.
+
+Sweating of soap, 62.
+
+Sweet water, 119.
+
+Sylvic acid, 22.
+
+
+T
+
+Talgol, 96.
+
+Tallow, 4.
+
+Tallow, Fullers' earth bleaching of, 4.
+
+Tallow, Improving color by extraction of free fatty acid, 6.
+
+Tannin soap, 78.
+
+Tar soap, 77.
+
+Test for color of soap, 133.
+
+Testing of alkalis used in soap making, 134.
+
+Textile soaps, 98.
+
+Titer, 130.
+
+Tank cars, Sampling, 166.
+
+Tierces, Sampling, 168.
+
+Titer, Standard method, 175.
+
+Titer, Note on, 189.
+
+Tung oil, Note one iodine, number of, 180.
+
+Toilet soap, 65.
+
+Toilet soaps, Cheaper, 68.
+
+Toilet soap, Use of hardened oils in, 96.
+
+Total alkali, Determination of in soap, 147.
+
+Total fatty and resin acids, Determination of in soap, 144.
+
+Train oils, 20.
+
+Transparent soap, 82.
+
+Transparent soap, Cold made, 84.
+
+Troweling soap, 52.
+
+Tsujimoto, ref., 20.
+
+Tubes for transparent soap, 85.
+
+Turkey red oil, 104.
+
+Twaddle scale, 25.
+
+Twitchell method for rosin, 145.
+
+Twitchell process, 113.
+
+Twitchell process, Advantages, 113.
+
+
+U
+
+Unsaponifiable matter, Determination of in oils and fats, 132.
+
+Unsaponifiable matter, Determination of in soap, 148.
+
+Unsaponifiable matter, determination of by standard method, 176.
+
+
+V
+
+Vacuum Oven, Standard, 176.
+
+Vegetable oils, 6.
+
+
+W
+
+Water, 29.
+
+Water, Hard, 29.
+
+Witch hazel soap, 78.
+
+Wool thrower's soap, 100.
+
+Worsted finishing soaps, 101.
+
+
+Z
+
+Zinc oxide, Use of in autoclave saponification, 120.
+
+Zinc oxide, Use of in soap, 33.
+
+
+
+
+LITERATURE OF THE CHEMICAL INDUSTRIES
+
+
+On our shelves is the most complete stock of technical, industrial,
+engineering and scientific books in the United States. The technical
+literature of every trade is well represented, as is also the literature
+relating to the various sciences, both the books useful for reference as
+well as those fitted for students' use as textbooks.
+
+A large number of these we publish and for an ever increasing number we
+are the sole agents.
+
+ALL INQUIRIES MADE OF US ARE CHEERFULLY AND CAREFULLY ANSWERED AND
+COMPLETE CATALOGS AS WELL AS SPECIAL LISTS SENT FREE ON REQUEST
+
+D. VAN NOSTRAND COMPANY
+
+_Publishers and Booksellers_
+
+8 WARREN STREET NEW YORK
+
+
+The Soap-Maker's Book Shelf
+
+A list of standard books relating to soapmaking and allied industries.
+
+Published and For Sale by
+
+D. VAN NOSTRAND COMPANY
+
+_Publishers and Booksellers_
+
+8 WARREN STREET          NEW YORK
+
+
+~Askinson, George W.~ Perfumes and Cosmetics. Their preparation and
+manufacture. Fourth Edition, translated from the German, and revised
+with additions by W. L. Dudley. 32 illustrations. 6-1/4 x 9-1/2. Cloth.
+354 pp. New York, 1915. ~$5.00~
+
+~Chalmers, T. W.~ The Production and Treatment of Vegetable Oils.
+Including chapters on the refining of oils, the hydrogenation of oils,
+the generation of hydrogen, soap making, the recovery and refining of
+glycerine, and the splitting of oils. 95 illustrations, 9 folding
+plates. 8 x 11-1/2. Cloth. 163 pp. London, 1919. ~$7.50~
+
+~Deite, C.~ Manual of Toilet Soap-Making. Comprising toilet soaps,
+medicated soaps, and other specialties. Second Revised Edition. 85
+illustrations. 6-1/2 x 10. Cloth. 356 pp. London, 1920. ~$7.50~
+
+~Ellis, Carleton G.~ The Hydrogenation of Oils, Catalyzers and Catalysis
+and the Generation of Hydrogen and Oxygen. Second Edition, thoroughly
+revised and enlarged. 240 illustrations. 6-1/4 x 9-1/2. Cloth. 767 pp.
+N. Y., 1919. ~$7.50~
+
+~Fischer, M. H.~ Soaps and Proteins, Their Colloid Chemistry in Theory and
+Practice. With the collaboration of G. D. McLaughlin and M. O. Hooker.
+114 illustrations. 6 x 9-1/4. Cloth. 281 pp. New York, 1921. ~$4.00~
+
+~Holde, D.~ The Examination of Hydrocarbon Oils, and of the Saponifiable
+Fats and Waxes. Translated from the Fourth German Edition by Edward
+Mueller. 115 illustrations. 6-1/4 x 9-1/4. Cloth. 499 pp. N. Y., 1915.
+~Net, $5.00~
+
+~Hurst, G. H~. Soaps. A practical manual of the manufacture of domestic,
+toilet and other soaps. Second Edition. 66 illustrations. 6 x 8-3/4.
+Cloth. 385 pp. London, 1907. ~$6.00~
+
+~Hurst, George H., and Simmons, W. H.~ Textile Soaps and Oils. A handbook
+on the preparation, properties, and analysis of the soaps and oils and
+in textile manufacturing, dyeing and printing. Third Edition, revised.
+12 illustrations. 5-1/2 x 8-3/4. Cloth. 212 pp. London, 1921. ~$4.00~
+
+~Koller, T. Cosmetics.~ A handbook of the manufacture, employment, and
+testing of all cosmetic materials and cosmetic specialties, with
+numerous recipes. Translated from the German. Third Edition. 5 x 7-1/2.
+Cloth. 264 pp. London, 1920. ~$3.50~
+
+~Koppe, S. W. Glycerine.~ Its introduction, Uses and Examination. For
+chemists, perfumers, soapmakers, pharmacists, and explosives
+technologists. 7 illustrations. 5-1/4 x 7-1/2. Cloth. 260 pp. New York,
+1915. ~$3.50~
+
+~Lamborn, L. L.~ Modern Soaps, Candles, and Glycerin. A practical manual
+of modern methods of utilization of fats and oils in the manufacture of
+soaps and candles, and the recovery of glycerin. 228 illustrations.
+6-1/2 x 9-1/4. Cloth. 708 pp. N. Y., 1906. ~$10.00~
+
+~Murray, B. L.~ Standards and Tests for Reagent Chemicals. 6 x 9. Cloth.
+400 pp. New York, 1920. ~$3.00~
+
+~Parry, Ernest J.~ The Chemistry of Essential Oils and Artificial
+Perfumes. Vol. I, Monographs on Essential Oils. Fourth Edition, revised
+and enlarged. 51 illustrations. 6-1/4 x 10. Cloth. 557 pp. London, 1921.
+~$9.00~
+
+Vol. II. Constituents of Essential Oils, Synthetic Perfumes and Isolated
+Aromatics, and the Analysis of Essential Oils. Third Edition, revised
+and enlarged. Illustrated. 351 pp. London, 1919. ~$7.00~
+
+~Partington, J. R.~ The Alkali Industry. 63 illustrations. 5-1/2 x 8-1/2.
+Cloth. 318 pp. London, 1918. ~$3.00~
+
+~Rogers, Allen.~ Industrial Chemistry. A manual for the student and
+manufacturer. Third Edition, thoroughly revised and enlarged. 377
+illustrations. 6-1/2 x 9-3/4. Flexible fabrikoid. 1255 pp. New York,
+1920. ~$7.50~
+
+~Scott, Wilfred W.~ (Editor). Standard Methods of Chemical Analysis. A
+manual of analytical methods and general reference for the analytical
+chemist and for the advanced student. Second Edition, revised, with
+additional tables. 142 illustrations, 3 color plates. 7 x 9-1/4. Cloth.
+900 pp. N. Y., 1917. ~$7.50~
+
+~Simmons, W. H.~ Fats, Waxes and Essential Oils. ~In Press.~
+
+~Simmons, William H.~ Soap. Its composition, manufacture and properties.
+11 illustrations. 4-3/4 x 7-1/4. Cloth. 133 pp. London, 1916. ~$1.00~
+
+~Simmons, W. H., and Appleton, H. A.~ The Handbook of Soap Manufacture. 27
+illustrations. 6 x 9. Cloth. 166 pp. London, 1908. ~$4.00~
+
+~Van Nostrand's Chemical Annual.~ Edited by John C. Olsen. A handbook of
+useful data for analytical manufacturing and investigating chemists and
+chemical students. Fourth Issue, enlarged. 5 x 7-1/2. Flexible
+fabrikoid. 785 pp. New York, 1918. ~$3.00~
+
+~Watt, A.~ Art of Soapmaking. A practical handbook of the manufacture of
+hard and soft soaps, toilet soaps, etc. Seventh Edition, revised and
+enlarged. 43 illustrations. 5-1/4 x 7-1/2. Cloth. 323 pp. London, 1918.
+~$4.00~
+
+~Wright, C. R. A.~ Animal and Vegetable Fixed Oils, Fats, Butters, and
+Waxes: Their Preparation and Properties, and the Manufacture Therefrom
+of Candles, Soaps, and Other Products. Third Edition, revised and
+greatly enlarged by C. Ainsworth Mitchell. 185 illustrations, 3 plates.
+6 x 9. Cloth. 953 pp. London, 1921. ~$16.50~
+
+
+
+
+
+
+End of the Project Gutenberg EBook of Soap-Making Manual, by E. G. Thomssen
+
+*** END OF THIS PROJECT GUTENBERG EBOOK SOAP-MAKING MANUAL ***
+
+***** This file should be named 34114.txt or 34114.zip *****
+This and all associated files of various formats will be found in:
+        https://www.gutenberg.org/3/4/1/1/34114/
+
+Produced by David Clarke, Josephine Paolucci and the Online
+Distributed Proofreading Team at https://www.pgdp.net. (This
+file was produced from images generously made available
+by The Internet Archive/American Libraries.)
+
+
+Updated editions will replace the previous one--the old editions
+will be renamed.
+
+Creating the works from public domain print editions means that no
+one owns a United States copyright in these works, so the Foundation
+(and you!) can copy and distribute it in the United States without
+permission and without paying copyright royalties.  Special rules,
+set forth in the General Terms of Use part of this license, apply to
+copying and distributing Project Gutenberg-tm electronic works to
+protect the PROJECT GUTENBERG-tm concept and trademark.  Project
+Gutenberg is a registered trademark, and may not be used if you
+charge for the eBooks, unless you receive specific permission.  If you
+do not charge anything for copies of this eBook, complying with the
+rules is very easy.  You may use this eBook for nearly any purpose
+such as creation of derivative works, reports, performances and
+research.  They may be modified and printed and given away--you may do
+practically ANYTHING with public domain eBooks.  Redistribution is
+subject to the trademark license, especially commercial
+redistribution.
+
+
+
+*** START: FULL LICENSE ***
+
+THE FULL PROJECT GUTENBERG LICENSE
+PLEASE READ THIS BEFORE YOU DISTRIBUTE OR USE THIS WORK
+
+To protect the Project Gutenberg-tm mission of promoting the free
+distribution of electronic works, by using or distributing this work
+(or any other work associated in any way with the phrase "Project
+Gutenberg"), you agree to comply with all the terms of the Full Project
+Gutenberg-tm License (available with this file or online at
+https://gutenberg.org/license).
+
+
+Section 1.  General Terms of Use and Redistributing Project Gutenberg-tm
+electronic works
+
+1.A.  By reading or using any part of this Project Gutenberg-tm
+electronic work, you indicate that you have read, understand, agree to
+and accept all the terms of this license and intellectual property
+(trademark/copyright) agreement.  If you do not agree to abide by all
+the terms of this agreement, you must cease using and return or destroy
+all copies of Project Gutenberg-tm electronic works in your possession.
+If you paid a fee for obtaining a copy of or access to a Project
+Gutenberg-tm electronic work and you do not agree to be bound by the
+terms of this agreement, you may obtain a refund from the person or
+entity to whom you paid the fee as set forth in paragraph 1.E.8.
+
+1.B.  "Project Gutenberg" is a registered trademark.  It may only be
+used on or associated in any way with an electronic work by people who
+agree to be bound by the terms of this agreement.  There are a few
+things that you can do with most Project Gutenberg-tm electronic works
+even without complying with the full terms of this agreement.  See
+paragraph 1.C below.  There are a lot of things you can do with Project
+Gutenberg-tm electronic works if you follow the terms of this agreement
+and help preserve free future access to Project Gutenberg-tm electronic
+works.  See paragraph 1.E below.
+
+1.C.  The Project Gutenberg Literary Archive Foundation ("the Foundation"
+or PGLAF), owns a compilation copyright in the collection of Project
+Gutenberg-tm electronic works.  Nearly all the individual works in the
+collection are in the public domain in the United States.  If an
+individual work is in the public domain in the United States and you are
+located in the United States, we do not claim a right to prevent you from
+copying, distributing, performing, displaying or creating derivative
+works based on the work as long as all references to Project Gutenberg
+are removed.  Of course, we hope that you will support the Project
+Gutenberg-tm mission of promoting free access to electronic works by
+freely sharing Project Gutenberg-tm works in compliance with the terms of
+this agreement for keeping the Project Gutenberg-tm name associated with
+the work.  You can easily comply with the terms of this agreement by
+keeping this work in the same format with its attached full Project
+Gutenberg-tm License when you share it without charge with others.
+
+1.D.  The copyright laws of the place where you are located also govern
+what you can do with this work.  Copyright laws in most countries are in
+a constant state of change.  If you are outside the United States, check
+the laws of your country in addition to the terms of this agreement
+before downloading, copying, displaying, performing, distributing or
+creating derivative works based on this work or any other Project
+Gutenberg-tm work.  The Foundation makes no representations concerning
+the copyright status of any work in any country outside the United
+States.
+
+1.E.  Unless you have removed all references to Project Gutenberg:
+
+1.E.1.  The following sentence, with active links to, or other immediate
+access to, the full Project Gutenberg-tm License must appear prominently
+whenever any copy of a Project Gutenberg-tm work (any work on which the
+phrase "Project Gutenberg" appears, or with which the phrase "Project
+Gutenberg" is associated) is accessed, displayed, performed, viewed,
+copied or distributed:
+
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever.  You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at www.gutenberg.org
+
+1.E.2.  If an individual Project Gutenberg-tm electronic work is derived
+from the public domain (does not contain a notice indicating that it is
+posted with permission of the copyright holder), the work can be copied
+and distributed to anyone in the United States without paying any fees
+or charges.  If you are redistributing or providing access to a work
+with the phrase "Project Gutenberg" associated with or appearing on the
+work, you must comply either with the requirements of paragraphs 1.E.1
+through 1.E.7 or obtain permission for the use of the work and the
+Project Gutenberg-tm trademark as set forth in paragraphs 1.E.8 or
+1.E.9.
+
+1.E.3.  If an individual Project Gutenberg-tm electronic work is posted
+with the permission of the copyright holder, your use and distribution
+must comply with both paragraphs 1.E.1 through 1.E.7 and any additional
+terms imposed by the copyright holder.  Additional terms will be linked
+to the Project Gutenberg-tm License for all works posted with the
+permission of the copyright holder found at the beginning of this work.
+
+1.E.4.  Do not unlink or detach or remove the full Project Gutenberg-tm
+License terms from this work, or any files containing a part of this
+work or any other work associated with Project Gutenberg-tm.
+
+1.E.5.  Do not copy, display, perform, distribute or redistribute this
+electronic work, or any part of this electronic work, without
+prominently displaying the sentence set forth in paragraph 1.E.1 with
+active links or immediate access to the full terms of the Project
+Gutenberg-tm License.
+
+1.E.6.  You may convert to and distribute this work in any binary,
+compressed, marked up, nonproprietary or proprietary form, including any
+word processing or hypertext form.  However, if you provide access to or
+distribute copies of a Project Gutenberg-tm work in a format other than
+"Plain Vanilla ASCII" or other format used in the official version
+posted on the official Project Gutenberg-tm web site (www.gutenberg.org),
+you must, at no additional cost, fee or expense to the user, provide a
+copy, a means of exporting a copy, or a means of obtaining a copy upon
+request, of the work in its original "Plain Vanilla ASCII" or other
+form.  Any alternate format must include the full Project Gutenberg-tm
+License as specified in paragraph 1.E.1.
+
+1.E.7.  Do not charge a fee for access to, viewing, displaying,
+performing, copying or distributing any Project Gutenberg-tm works
+unless you comply with paragraph 1.E.8 or 1.E.9.
+
+1.E.8.  You may charge a reasonable fee for copies of or providing
+access to or distributing Project Gutenberg-tm electronic works provided
+that
+
+- You pay a royalty fee of 20% of the gross profits you derive from
+     the use of Project Gutenberg-tm works calculated using the method
+     you already use to calculate your applicable taxes.  The fee is
+     owed to the owner of the Project Gutenberg-tm trademark, but he
+     has agreed to donate royalties under this paragraph to the
+     Project Gutenberg Literary Archive Foundation.  Royalty payments
+     must be paid within 60 days following each date on which you
+     prepare (or are legally required to prepare) your periodic tax
+     returns.  Royalty payments should be clearly marked as such and
+     sent to the Project Gutenberg Literary Archive Foundation at the
+     address specified in Section 4, "Information about donations to
+     the Project Gutenberg Literary Archive Foundation."
+
+- You provide a full refund of any money paid by a user who notifies
+     you in writing (or by e-mail) within 30 days of receipt that s/he
+     does not agree to the terms of the full Project Gutenberg-tm
+     License.  You must require such a user to return or
+     destroy all copies of the works possessed in a physical medium
+     and discontinue all use of and all access to other copies of
+     Project Gutenberg-tm works.
+
+- You provide, in accordance with paragraph 1.F.3, a full refund of any
+     money paid for a work or a replacement copy, if a defect in the
+     electronic work is discovered and reported to you within 90 days
+     of receipt of the work.
+
+- You comply with all other terms of this agreement for free
+     distribution of Project Gutenberg-tm works.
+
+1.E.9.  If you wish to charge a fee or distribute a Project Gutenberg-tm
+electronic work or group of works on different terms than are set
+forth in this agreement, you must obtain permission in writing from
+both the Project Gutenberg Literary Archive Foundation and Michael
+Hart, the owner of the Project Gutenberg-tm trademark.  Contact the
+Foundation as set forth in Section 3 below.
+
+1.F.
+
+1.F.1.  Project Gutenberg volunteers and employees expend considerable
+effort to identify, do copyright research on, transcribe and proofread
+public domain works in creating the Project Gutenberg-tm
+collection.  Despite these efforts, Project Gutenberg-tm electronic
+works, and the medium on which they may be stored, may contain
+"Defects," such as, but not limited to, incomplete, inaccurate or
+corrupt data, transcription errors, a copyright or other intellectual
+property infringement, a defective or damaged disk or other medium, a
+computer virus, or computer codes that damage or cannot be read by
+your equipment.
+
+1.F.2.  LIMITED WARRANTY, DISCLAIMER OF DAMAGES - Except for the "Right
+of Replacement or Refund" described in paragraph 1.F.3, the Project
+Gutenberg Literary Archive Foundation, the owner of the Project
+Gutenberg-tm trademark, and any other party distributing a Project
+Gutenberg-tm electronic work under this agreement, disclaim all
+liability to you for damages, costs and expenses, including legal
+fees.  YOU AGREE THAT YOU HAVE NO REMEDIES FOR NEGLIGENCE, STRICT
+LIABILITY, BREACH OF WARRANTY OR BREACH OF CONTRACT EXCEPT THOSE
+PROVIDED IN PARAGRAPH 1.F.3.  YOU AGREE THAT THE FOUNDATION, THE
+TRADEMARK OWNER, AND ANY DISTRIBUTOR UNDER THIS AGREEMENT WILL NOT BE
+LIABLE TO YOU FOR ACTUAL, DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE OR
+INCIDENTAL DAMAGES EVEN IF YOU GIVE NOTICE OF THE POSSIBILITY OF SUCH
+DAMAGE.
+
+1.F.3.  LIMITED RIGHT OF REPLACEMENT OR REFUND - If you discover a
+defect in this electronic work within 90 days of receiving it, you can
+receive a refund of the money (if any) you paid for it by sending a
+written explanation to the person you received the work from.  If you
+received the work on a physical medium, you must return the medium with
+your written explanation.  The person or entity that provided you with
+the defective work may elect to provide a replacement copy in lieu of a
+refund.  If you received the work electronically, the person or entity
+providing it to you may choose to give you a second opportunity to
+receive the work electronically in lieu of a refund.  If the second copy
+is also defective, you may demand a refund in writing without further
+opportunities to fix the problem.
+
+1.F.4.  Except for the limited right of replacement or refund set forth
+in paragraph 1.F.3, this work is provided to you 'AS-IS' WITH NO OTHER
+WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
+WARRANTIES OF MERCHANTIBILITY OR FITNESS FOR ANY PURPOSE.
+
+1.F.5.  Some states do not allow disclaimers of certain implied
+warranties or the exclusion or limitation of certain types of damages.
+If any disclaimer or limitation set forth in this agreement violates the
+law of the state applicable to this agreement, the agreement shall be
+interpreted to make the maximum disclaimer or limitation permitted by
+the applicable state law.  The invalidity or unenforceability of any
+provision of this agreement shall not void the remaining provisions.
+
+1.F.6.  INDEMNITY - You agree to indemnify and hold the Foundation, the
+trademark owner, any agent or employee of the Foundation, anyone
+providing copies of Project Gutenberg-tm electronic works in accordance
+with this agreement, and any volunteers associated with the production,
+promotion and distribution of Project Gutenberg-tm electronic works,
+harmless from all liability, costs and expenses, including legal fees,
+that arise directly or indirectly from any of the following which you do
+or cause to occur: (a) distribution of this or any Project Gutenberg-tm
+work, (b) alteration, modification, or additions or deletions to any
+Project Gutenberg-tm work, and (c) any Defect you cause.
+
+
+Section  2.  Information about the Mission of Project Gutenberg-tm
+
+Project Gutenberg-tm is synonymous with the free distribution of
+electronic works in formats readable by the widest variety of computers
+including obsolete, old, middle-aged and new computers.  It exists
+because of the efforts of hundreds of volunteers and donations from
+people in all walks of life.
+
+Volunteers and financial support to provide volunteers with the
+assistance they need are critical to reaching Project Gutenberg-tm's
+goals and ensuring that the Project Gutenberg-tm collection will
+remain freely available for generations to come.  In 2001, the Project
+Gutenberg Literary Archive Foundation was created to provide a secure
+and permanent future for Project Gutenberg-tm and future generations.
+To learn more about the Project Gutenberg Literary Archive Foundation
+and how your efforts and donations can help, see Sections 3 and 4
+and the Foundation web page at https://www.pglaf.org.
+
+
+Section 3.  Information about the Project Gutenberg Literary Archive
+Foundation
+
+The Project Gutenberg Literary Archive Foundation is a non profit
+501(c)(3) educational corporation organized under the laws of the
+state of Mississippi and granted tax exempt status by the Internal
+Revenue Service.  The Foundation's EIN or federal tax identification
+number is 64-6221541.  Its 501(c)(3) letter is posted at
+https://pglaf.org/fundraising.  Contributions to the Project Gutenberg
+Literary Archive Foundation are tax deductible to the full extent
+permitted by U.S. federal laws and your state's laws.
+
+The Foundation's principal office is located at 4557 Melan Dr. S.
+Fairbanks, AK, 99712., but its volunteers and employees are scattered
+throughout numerous locations.  Its business office is located at
+809 North 1500 West, Salt Lake City, UT 84116, (801) 596-1887, email
+business@pglaf.org.  Email contact links and up to date contact
+information can be found at the Foundation's web site and official
+page at https://pglaf.org
+
+For additional contact information:
+     Dr. Gregory B. Newby
+     Chief Executive and Director
+     gbnewby@pglaf.org
+
+
+Section 4.  Information about Donations to the Project Gutenberg
+Literary Archive Foundation
+
+Project Gutenberg-tm depends upon and cannot survive without wide
+spread public support and donations to carry out its mission of
+increasing the number of public domain and licensed works that can be
+freely distributed in machine readable form accessible by the widest
+array of equipment including outdated equipment.  Many small donations
+($1 to $5,000) are particularly important to maintaining tax exempt
+status with the IRS.
+
+The Foundation is committed to complying with the laws regulating
+charities and charitable donations in all 50 states of the United
+States.  Compliance requirements are not uniform and it takes a
+considerable effort, much paperwork and many fees to meet and keep up
+with these requirements.  We do not solicit donations in locations
+where we have not received written confirmation of compliance.  To
+SEND DONATIONS or determine the status of compliance for any
+particular state visit https://pglaf.org
+
+While we cannot and do not solicit contributions from states where we
+have not met the solicitation requirements, we know of no prohibition
+against accepting unsolicited donations from donors in such states who
+approach us with offers to donate.
+
+International donations are gratefully accepted, but we cannot make
+any statements concerning tax treatment of donations received from
+outside the United States.  U.S. laws alone swamp our small staff.
+
+Please check the Project Gutenberg Web pages for current donation
+methods and addresses.  Donations are accepted in a number of other
+ways including including checks, online payments and credit card
+donations.  To donate, please visit: https://pglaf.org/donate
+
+
+Section 5.  General Information About Project Gutenberg-tm electronic
+works.
+
+Professor Michael S. Hart was the originator of the Project Gutenberg-tm
+concept of a library of electronic works that could be freely shared
+with anyone.  For thirty years, he produced and distributed Project
+Gutenberg-tm eBooks with only a loose network of volunteer support.
+
+
+Project Gutenberg-tm eBooks are often created from several printed
+editions, all of which are confirmed as Public Domain in the U.S.
+unless a copyright notice is included.  Thus, we do not necessarily
+keep eBooks in compliance with any particular paper edition.
+
+
+Most people start at our Web site which has the main PG search facility:
+
+     https://www.gutenberg.org
+
+This Web site includes information about Project Gutenberg-tm,
+including how to make donations to the Project Gutenberg Literary
+Archive Foundation, how to help produce our new eBooks, and how to
+subscribe to our email newsletter to hear about new eBooks.
diff --git a/34114.zip b/34114.zip
new file mode 100644
index 0000000..5bcb1fb
--- /dev/null
+++ b/34114.zip
diff --git a/LICENSE.txt b/LICENSE.txt
new file mode 100644
index 0000000..6312041
--- /dev/null
+++ b/LICENSE.txt
@@ -0,0 +1,11 @@
+This eBook, including all associated images, markup, improvements,
+metadata, and any other content or labor, has been confirmed to be
+in the PUBLIC DOMAIN IN THE UNITED STATES.
+
+Procedures for determining public domain status are described in
+the "Copyright How-To" at https://www.gutenberg.org.
+
+No investigation has been made concerning possible copyrights in
+jurisdictions other than the United States. Anyone seeking to utilize
+this eBook outside of the United States should confirm copyright
+status under the laws that apply to them.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..21b9113
--- /dev/null
+++ b/README.md
@@ -0,0 +1,2 @@
+Project Gutenberg (https://www.gutenberg.org) public repository for
+eBook #34114 (https://www.gutenberg.org/ebooks/34114)