diff options
Diffstat (limited to '37743.txt')
| -rw-r--r-- | 37743.txt | 1041 |
1 files changed, 1041 insertions, 0 deletions
diff --git a/37743.txt b/37743.txt new file mode 100644 index 0000000..998bc43 --- /dev/null +++ b/37743.txt @@ -0,0 +1,1041 @@ +Project Gutenberg's The Attitudes of Animals in Motion, by Eadweard Muybridge + +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: The Attitudes of Animals in Motion + Illustrated with the Zoopraxiscope + +Author: Eadweard Muybridge + +Release Date: October 13, 2011 [EBook #37743] + +Language: English + +Character set encoding: ASCII + +*** START OF THIS PROJECT GUTENBERG EBOOK THE ATTITUDES OF ANIMALS IN MOTION *** + + + + +Produced by Mark C. Orton, Alex Gam and the Online +Distributed Proofreading Team at http://www.pgdp.net (This +file was produced from images generously made available +by The Internet Archive) + + + + + + + + +Royal Institution of Great Britain. + +EXTRA EVENING MEETING, + +Monday, March 13, 1882. + +H.R.H. THE PRINCE OF WALES, K.G. F.R.S. Vice-Patron and +Honorary Member, in the Chair. + +EADWEARD MUYBRIDGE, of San Francisco. + + + +_The Attitudes of Animals in Motion, illustrated with the +Zoopraxiscope._ + + +The problem of animal mechanism has engaged the attention of mankind +during the entire period of the world's history. + +Job describes the action of the horse; Homer, that of the ox; it engaged +the profound attention of Aristotle, and Borelli devoted a lifetime to +its attempted solution. In every age, and in every country, philosophers +have found it a subject of exhaustless research. Marey, the eminent +French savant of our own day, dissatisfied with the investigations of his +predecessors, and with the object of obtaining more accurate information +than their works afforded him, employed a system of flexible tubes, +connected at one end with elastic air-chambers, which were attached to +the shoes of a horse; and at the other end with some mechanism, held in +the hand of the animal's rider. The alternate compression and expansion +of the air in the chambers caused pencils to record upon a revolving +cylinder the successive or simultaneous action of each foot, as it +correspondingly rested upon or was raised from the ground. By this +original and ingenious method, much interesting and valuable information +was obtained, and new light thrown upon movements until then but +imperfectly understood. + +While the philosopher was exhausting his endeavours to expound the laws +that control, and the elements that effect the movements associated with +animal life, the artist, with a few exceptions, seems to have been +content with the observations of his earliest predecessors in design, and +to have accepted as authentic without further inquiry, the pictorial and +sculptural representations of moving animals bequeathed from the remote +ages of tradition. + +When the body of an animal is being carried forward with uniform motion, +the limbs in their relations to it have alternately a progressive and a +retrogressive action, their various portions accelerating in comparative +speed and repose as they extend downwards to the feet, which are +subjected to successive changes from a condition of absolute rest, to a +varying increased velocity in comparison with that of the body. + +The action of no single limb can be availed of for artistic purposes +without a knowledge of the synchronous action of the other limbs; and to +the extreme difficulty, almost impossibility, of the mind being capable +of appreciating the simultaneous motion of the four limbs of an animal, +even in the slower movements, may be attributed the innumerable errors +into which investigators by observation have been betrayed. When these +synchronous movements and the successive attitudes they occasion are +understood, we at once see the simplicity of animal locomotion, in all +its various types and alternations. The walk of a quadruped being its +slowest progressive movement would seem to be a very simple action, easy +of observation and presenting but little difficulty for analysis, yet it +has occasioned interminable controversies among the closest and most +experienced observers. + +When, during a gallop, the fore and hind legs are severally and +consecutively thrust forwards and backwards to their fullest extent, +their comparative inaction may create in the mind of the careless +observer an impression of indistinct outlines; these successive +appearances were probably combined by the earliest sculptors and +painters, and with grotesque exaggeration adopted as the solitary +position to illustrate great speed. Or, as is very likely, excessive +projection of limb was intended to symbolise speed, just as excess in +size was an indication of rank. This opinion is to some extent +corroborated by the productions of the Grecian artists in their best +period, when their heroes are represented of the same size as other men, +and their horses in attitudes more nearly resembling those possible for +them to assume. The remarkable conventional attitude of the Egyptians, +however, has, with few modifications, been used by artists of nearly +every age to represent the action of galloping, and prevails without +recognised correction in all civilised countries at the present day. + +The ambition and perhaps also the province of art in its most exalted +sense, is to be a delineator of impressions, a creator of effects, rather +than a recorder of facts. Whether in the illustrations of the attitudes +of animals in motion the artist is justified in sacrificing truth, for an +impression so vague as to be dispelled by the first studied observation, +is a question perhaps as much a subject of controversy now as it was in +the time of Lysippus, who ridiculed other sculptors for making men as +they existed in nature; boasting that he himself made them as they ought +to be. + +A few eminent artists, notable among whom is Meissonier, have endeavoured +in depicting the slower movements of animals to invoke the aid of truth +instead of imagination to direct their pencil, but with little +encouragement from their critics; until recently, however, artists and +critics alike have necessarily had to depend upon their observation alone +to justify their conceptions or to support their theories. + +Photography, at first regarded as a curiosity of science, was soon +recognised as a most important factor in the search for truth, and its +more popular use is now entirely subordinated by its value to the +astronomer, the anatomist, the pathologist, and other investigators of +the complex problems of nature. The artist, however, still hesitates to +avail himself of the resources of what may be at least acknowledged as a +handmaiden of art, if not admitted to its most exalted ranks. + +Having devoted much attention in California to experiments in +instantaneous photography, I, in 1872, at the suggestion of the editor of +a San Francisco newspaper, obtained a few photographic impressions of a +horse during a fast trot. + +At this time much controversy prevailed among experienced horsemen as to +whether all the feet of a horse while trotting were entirely clear of the +ground at the same instant of time. A few experiments made in that year +proved a fact which should have been self-evident. + +Being much interested with the experiments of Professor Marey, in 1877 I +invented a method for the employment of a number of photographic cameras, +arranged in a line parallel to a track over which the animal would be +caused to move, with the object of obtaining, at regulated intervals of +time or distance, several consecutive impressions of him during a single +complete stride as he passed along in front of the cameras, and so of +more completely investigating the successive attitudes of animals while +in motion than could be accomplished by the system of M. Marey. + +I explained the plan of my intended experiments to a wealthy resident of +San Francisco--Mr. Stanford--who liberally agreed to place the resources +of his stock-breeding farm at my disposal, and to reimburse the expenses +of my investigations, upon condition of my supplying him, for his private +use, with a few copies of the contemplated results. The apparatus used +and its arrangement will be better understood by a reference to the +accompanying drawings. + +[Illustration: FIG. 1.] + +[Illustration: FIG. 2.] + +[Illustration: FIG. 3.] + +[Illustration: FIG. 4.] + +Fig. 1. A photographing lens, and camera containing a sensitised plate; +and side view of electro-exposor placed in front of camera. + +Fig. 2. Back view of electro-exposor. Two shutters P P, each comprising +two panels, with an opening O between them, are adjusted to move freely +up and down in a frame; they are here arranged ready for an exposure, and +are held in position by a latch L and trigger T, all light being excluded +from the lens. A slight extra tension of the thread B, Fig. 4, will cause +a contact of the metal springs M S, and complete a circuit of electricity +through the wires W W and the electro-magnet M; the consequent attraction +causes the armature A to strike the trigger, the latch is released, the +shutters are drawn respectively upwards and downwards by means of the +rubber springs S S, and light is admitted to the sensitised plate while +the openings in the shutters are passing each other in front of the lens. + +Fig. 3. Front view of electro-exposor after exposure of the plate. + +[Illustration: FIG. 5.] + +Fig. 5. General view of studio, operating track, and background. In the +studio are arranged 24 photographing cameras; at a distance of 12 inches +from the centre of each lens an electro-exposor is securely fixed in +front of each camera. Threads 12 inches apart are stretched across the +track (only two of which are introduced in the engraving), at a suitable +height to strike the breast of the animal experimented with, one end of +the thread being fastened to the background, the other to the spring, +Fig. 4, which is drawn almost to the point of contact. + +The animal in its progress over the track will strike these threads in +succession, and as each pair of springs is brought into contact, the +current of electricity thereby created effects a photographic exposure, +as described by Figs. 2 and 4; and each consecutive exposure records the +position of the animal at the instant the thread is struck and broken. + +For obtaining successive exposures of horses driven in vehicles, one of +the wheels is steered in a channel over wires slightly elevated from the +ground; the depression of each wire completes an electric circuit, and +effects the exposures in the same manner as the threads. + +[Illustration: FIG. 6.] + +Fig. 6. Operating track, covered with corrugated indiarubber, and marked +with transverse lines 12 inches apart. Each line is numbered, for the +purpose of more readily ascertaining the length of the animal's stride. +On one side of the track, and opposite to the battery of cameras, a white +background is erected at a suitable angle. + +The camera in which any one negative in a series of exposures is made is +designated on that negative by the parallel direction of the vertical +stake with the horizontal line extending to the corresponding number +immediately opposite. The discriminating number of each series is marked +on each negative by the large numbers--229, for example--which are +changed for each movement illustrated. + +For recording the successive attitudes of animals not under control, an +apparatus is used, comprising a cylinder, around which are spirally +arranged a number of pins; upon the cylinder being set in motion through +gearing connected with a spring or weight, these pins are consecutively +brought into contact with a corresponding number of metal springs; a +succession of electric currents are thereby created which act through +their respective magnets attached to the electro-exposors at regulated +intervals of time. The cylinder is put in motion either by bringing it +into gearing with other parts of the apparatus already in motion; or by +releasing a break with the hand, or by the action of some object at a +distance by means of an electric current. + +This apparatus is principally used for illustrating the flight of birds, +the motions of small animals, and changes of position without continuous +progressive motion, such as occur during wrestling or turning a +summersault; when the cameras are directed towards the place where the +movements are being executed. + +The boxes outside the studio (Fig. 5) contain cameras and +electro-exposors for obtaining synchronous exposures of a moving object +from different points of view. + +The following analyses of some of the movements investigated by the aid +of electro-photographic exposures, are repeated by permission of the +President and Council from a paper read by the author before the Royal +Society, and are rendered more perfectly intelligible by the +reproductions of the actual motions projected on a screen through the +zoopraxiscope. + + +_The Walk._ + +Selecting the horse for the purposes of illustration, we find that during +his slowest progressive movement--the walk--he has always two, and, for a +varying period, three feet on the ground at once. With a fast walking +horse the time of support upon three feet is exceedingly brief; while +during a very slow walk all four feet are occasionally on the ground at +the same instant. + +The successive order of what may be termed foot fallings are these. +Commencing with the landing of the left hind foot, the next to strike the +ground will be the left fore foot, followed in order by the right hind, +and right fore foot. So far as the camera has revealed, these successive +foot fallings during the walk are invariable, and are probably common to +all quadrupeds. But the time during which each foot, in its relation to +the other feet, remains on the ground, varies greatly with different +species of animals, and even with the same animal under different +conditions. During an ordinary walk, at the instant preceding the +striking of the left hind foot, the body is supported on the right +laterals, and the left fore foot is in act of passing to the front of the +right fore foot. The two hind feet and the right fore foot immediately +divide the weight. The right hind foot is now raised, and the left hind +with its diagonal fore foot sustains the body; the left fore next touches +the ground and for an instant the animal is again on three feet; the +right fore foot is immediately raised and again the support is derived +from laterals--the left instead of as before the right. One half of the +stride is now completed, and a similar series of alternations, +substituting the right feet for the left, completes the other half. These +movements will perhaps be more readily understood by a reference to the +longitudinal elevation, Fig. 7, No. 1, which illustrates some approximate +relative positions of the feet of a rapid walking horse, with a stride of +5 feet 9 inches. The positions of the feet indicated in this, and also in +the other strides illustrated in Fig. 7 are copied from photographs, and +from them we learn that during an ordinary walk the consecutive +supporting feet are: + + 1. The left hind and left fore--_laterals_. + 2. Both hind, and left fore. + 3. Right hind and left fore--_diagonals_. + 4. Right hind and both fore. + 5. Right hind and right fore--_laterals_. + 6. Both hind, and right fore. + 7. Left hind and right fore--_diagonals_. + 8. Left hind and both fore. + +[Illustration: LONGITUDINAL ELEVATION OF SOME CONSECUTIVE POSITIONS OF +THE FEET OF HORSES DURING VARIOUS MOVEMENTS. + +Each line illustrates a single complete stride. The comparative distances +of the feet from each other, or from the ground, are approximate; not to +scale. Direction of movement --> + + _KEY._ + _Rt._ _Left._ + _Hind Feet_ + _Fore Feet_ + _Line of ground_ + + Length of + Action. Stride. 1 2 3 4 5 6 1D 2D 3D 4D 5D 6D + + ft. in. + 1. Walking 5 9 + 2. Trotting 7 6 + 3. " 17 6 + 4. " 18 3 + 5. Ambling 10 3 + 6. Racking 12 6 + + 1 2 3 4 5 6 7 8 9 10 11 12 + 7. Cantering 10 3 + 8. Galloping 11 9 + 9. " 19 9 + 10. Galloping, a conjectural stride } + of 22 feet or more } +] + +Commencing again with the first position; it is thus seen that when a +horse during a walk is on two feet, and the other two feet are suspended +between the supporting legs, the suspended feet are laterals. On the +other hand, when the suspended feet are severally in advance of and +behind the supporting legs, they are diagonals. + +These invariable rules seem to be neglected or entirely ignored by many +of the most eminent animal painters of modern times. + + +_The Trot._ + +By some observers the perfect trot is described as an absolutely +synchronous movement of the diagonal feet. This simultaneous action may +be considered desirable, but it probably never occurs. + +Sometimes the fore foot will be raised before the diagonal hind foot, +sometimes afterwards; but in either instance, the foot raised first will +strike the ground first; repeated experiments with many racing and other +trotting horses confirmed this want of simultaneity. Selecting for an +example of the trot a horse making a stride of 18 feet in length, we find +that at the instant his right fore foot strikes the ground, the left hind +foot is a few inches behind the point where it will presently strike at +about 38 or 40 inches to the rear of the fore foot. When both feet have +reached the ground, the right hind leg is stretched back almost to its +fullest extent, with the pastern nearly horizontal, while the left fore +leg is flexed under the body. As the legs approach a vertical position +the pasterns are gradually lowered, and act as springs to break the force +of the concussion until they are bent nearly at right angles with the +legs. + +At this period the left fore foot is raised to its greatest height, and +will frequently strike the elbow, while the right hind foot is but little +raised from the ground and is about to pass to the front of the left +hind. + +The pasterns gradually rise as the legs decline backwards until the right +fore foot has left the ground and the last propelling force is being +exercised by the left hind foot; which accomplished, the animal is in mid +air. + +The right hind foot continues its onward motion until it is sometimes +much in advance of its lateral fore foot, the former, however, being +gradually lowered, while the latter is being raised. The right hind and +both fore legs are now much flexed, while the left hind is stretched +backwards to its greatest extent with the bottom of the foot turned +upwards, the left fore leg is being thrust forwards and gradually +straightened, with the toe raised as the foot approaches the ground; +which accomplished, with a substitution of the left limbs for the right +we find them in the same relative positions as when we commenced our +examination, and one half of the stride is completed. + +With slight and immaterial differences, such as might be caused by +irregularities of the ground, these movements are repeated by the other +pair of diagonals, and the entire stride is then complete. + +Line 4 illustrates a stride of 18 feet 3 inches, and the order of +supporting feet are:-- + + 1. The right fore foot. + 2. The left hind and right fore feet. + 3. The left hind foot. + 4. Without support. + 5. The left fore foot. + 6. The right hind and left fore feet. + 7. The right hind foot. + 8. Without support. + +It appears somewhat remarkable that until the results of M. Marey's +experiments and of those obtained by electro-photography were published, +many experienced horsemen were of opinion that during the action of +trotting at least one foot of a horse was always in contact with the +ground. + +If the entire stride of a trotting horse is divided into two portions, +representing the comparative distances traversed by the aggregate of the +body while the feet are in contact with, and while they are entirely +clear of, the ground; the relative measurements will be found to vary +very greatly, they being contingent upon length of limb, weight, speed, +and other circumstances. + +Heavily built horses will sometimes merely drag the feet just above the +surface, but, in every instance of a trot, the _weight_ of the body is +really unsupported twice during each stride (see stride 2, positions 4 +and 4D). It sometimes happens that a fast trotter, during the two actions +of a stride, will have all his feet clear of the ground for a distance +exceeding one-half of the length of the entire stride; this elasticity of +movement is however exceptional. + +The action of a fast-trotting horse while drawing a vehicle is very +different from his action under the saddle; in the latter case, the hind +legs are kept thrust back for a longer period, and their final forward +movement is much more rapid. + + +_The Amble._ + +Assuming our observation of this movement to commence when, during a +stride of about 10 feet, the left hind foot has just struck the ground +slightly to the rear of where the right fore foot is resting; the left +fore leg will be well advanced but still flexed, with the toe pointed +downwards, and the right hind foot having been the last to leave the +ground, will be thrust backwards with the pastern nearly horizontal. + +As the right fore foot leaves the ground, the left fore leg is gradually +straightened during its thrust forwards; the right hind foot in the +meantime is gradually advancing, and the horse is supported on the left +hind foot alone. + +The left fore foot is now brought to the ground, and the body rests on +the left laterals, with the right laterals suspended between them. + +As the left fore leg attains a vertical position, its lateral leaves the +ground, and the support of the body devolves on the left fore foot alone, +the right fore leg being considerably flexed, with the foot in advance of +the left fore leg. + +The right hind foot now strikes the ground, and one half of the stride is +accomplished; these movements are repeated with a change of the limbs for +the remaining portion of the stride, and the horse is again in the +position in which we first observed him. + +We shall see by reference to stride No. 5 the consecutive supporting feet +to be: + + 1. The left hind foot. + 2. The left hind and left fore feet--_laterals_. + 3. The left fore foot. + 4. The left fore and right hind feet--_diagonals_. + 5. The right hind foot. + 6. The right hind and right fore feet--_laterals_. + 7. The right fore foot. + 8. The right fore and left hind feet--_diagonals_. + +The right fore foot being raised, the horse is again in the first +position. + +The amble and the walk are the only regular progressive movements of the +horse wherein the body is never without the support of one or more legs, +in all others the weight is entirely off the ground for a longer or +shorter period. + + +_The Rack or Pace._ + +The rack differs from the trot in the nearly synchronous action of the +_laterals_ instead of the _diagonals_. + +In some countries the rack is naturally adopted by the horse as one of +his gaits, but it is probably caused by the effects of training exercised +over many generations of his ancestors. + +The movements already described are regular in their action, and a stride +may be divided into two parts, which are essentially similar to each +other. + + +_The Canter_ + +and the gallop, however, cannot be so divided, and a complete stride in +either of those gaits is a combination of several different movements. + +The canter is usually regarded as a slow gallop, probably from the +facility with which a change from one gait to the other can be effected; +an important difference will, however, be observed. + +Assuming a horse after his propulsion through the air, during a stride of +10 feet, to have just landed on his left hind foot, the right hind foot +will be on the point of passing to the front of the left. The left fore +leg will be thrust forward and nearly straight, while the right fore leg +will be flexed with the foot elevated about 12 inches from the ground, +and somewhat behind the vertical of the breast. The left fore foot being +brought to the ground, the body is supported by the laterals; the right +hind foot is, however, quickly lowered, and performs its share of +support. The left hind foot is then raised, and the right hind and left +fore legs assume the weight, the former being nearly vertical, and the +latter inclined well back, the right fore foot is thrust well forward, +and is just about to strike the ground; when it does, three feet again +share the support, they being the two fore and the right hind. The left +fore foot now leaves the ground, and we again find the support furnished +by the laterals, the right instead of, as before, the left. + +The right hind foot is raised when the right fore leg becomes vertical; +this latter, which now sustains the entire weight, gives the final effort +of propulsion, and the body is hurled into the air. + +The descent of the left hind foot completes the stride, and the +consecutive movements are repeated. + +In stride No. 7 we learn that during the canter the support of the body +is derived from + + 1. The left hind foot. + 2. The left hind and left fore feet--_laterals_. + 3. Both hind and the left fore feet. + 4. The right hind and left fore feet--_diagonals_. + 5. The right hind and both fore feet. + 6. The right hind and right fore feet--_laterals_. + 7. The right fore foot alone, on which he leaves the ground. + + +_The Gallop or Run._ + +This movement has in all ages been employed by artists to convey the +impression of rapid motion, although, curiously enough, the attitude in +which the horse has been almost invariably depicted is one which is +impracticable during uniform progressive motion. + +When during a rapid gallop, with a stride of 20 feet, a horse after his +flight through the air lands on his left hind foot, the right hind will +be suspended over it at an elevation of 12 or 15 inches, and several +inches to the rear of and above it the sole of the right fore foot will +be turned up almost horizontally, the left fore leg is flexed with the +foot under the breast at a height of 18 or 20 inches. + +The right hind foot strikes the ground some 36 inches in advance of the +left hind, each as they land being forward of the centre of gravity. + +The body is now thrust forward, and while the right hind pastern is still +almost horizontal, the left hind foot leaves the ground. At this time the +left fore leg is perfectly straight, the foot, with the toe much higher +than the heel, is thrust forward to a point almost vertical with the +nose, and at an elevation of about 12 inches the right fore knee is bent +at right angles, and the foot suspended under the breast at several +inches greater elevation than the left fore foot. + +The left fore foot now strikes the ground, 96 inches in advance of the +spot which the right hind foot is on the point of leaving, and for a +brief space of time the diagonals are upon the ground together. The left +fore leg, however, immediately assumes the entire responsibility of the +weight, and soon attains a vertical position, with its pastern at right +angles to it. + +In this position the right hind foot is thrust back to its fullest +extent, at an elevation of 12 or 14 inches, with the pastern nearly +horizontal. The left hind foot is considerably higher and somewhat more +forward; the right fore leg is straight, stretched forward, with the foot +about 15 inches from the ground, and almost on a perpendicular line from +the nose. The right fore foot strikes the ground 48 inches in advance of +the left fore, which, having nearly performed its office, is preparing to +leave the ground; the animal will then be supported on the right fore +foot alone, which immediately falls well to the rear of the centre of +gravity, which is sometimes passed by the left hind foot at a height of +about 12 inches; the right hind foot is some distance in the rear, and +the left fore foot, at a height of 24 inches, is suspended somewhat in +advance of its lateral. + +In this position the horse uses the right fore foot for a final act of +propulsion, and is carried in mid air for a distance of 60 inches, after +which the left hind foot descends, the stride is completed, and the +consecutive motions renewed. + +The measurements and positions herein given do not pretend to exactness, +as they must depend to some extent upon the capability, training, and +convenience of the animal; but they may be accepted as representing an +average stride of 20 feet with a horse in a fair condition for racing. + +From this analysis it will be seen, by reference to stride 9, that a +horse, during an ordinary gallop, is supported consecutively by: + + 1. The left hind foot, + 2. Both hind feet, + 3. The right hind foot, + 4. The right hind and left fore feet, + 5. The left fore foot, + 6. Both fore feet, + 7. The right fore foot, + +with which he leaves the ground, while the only position in which we find +him entirely without support is when all the legs are flexed under his +body. + +It is highly probable, however, that more exhaustive experiments with +long-striding horses in perfect training, will discover there is +sometimes an interval of suspension between the lifting of one fore foot +and the descent of the other; and also between the lifting of the second +hind foot which touches the ground, and the descent of its diagonal fore +foot (see imaginary stride 10). Should this latter be the case, it will, +from the necessary positions of the other limbs, afford but a very +shadowy pretext for the conventional attitude used by artists to +represent a gallop. It is extremely doubtful if there can be any interval +of suspension between the lifting of one hind foot and the descent of the +other, no matter what the length of stride. + +Many able scientists have written on the theory of the gallop, but I +believe Marey was the first to demonstrate, that in executing this +movement, the horse left the ground with a fore foot and landed on a hind +foot. + + +_The Leap._ + +There is little essential difference in general characteristics of either +of the several movements that have been described, but with a number of +experiments made with horses while leaping, no two were found to agree in +the manner of execution. The leap of the same horse at the same rate of +speed, with the same rider, over the same hurdle, disclosed much +variation in the rise, clearance, and descent of the animal. Apart from +this, the horses were not thoroughly trained leapers, and the results are +perhaps not representative of those that would be obtained from the +action of a well-trained hunting horse. A few motions were, however, +invariable. While the horse was raising his body to clear the hurdle, one +hind foot was always in advance of the other, and exercised its last +energy alone. + +On the descent, the concussion was always received by one fore foot, +supported by the other more or less rapidly, and sometimes as much as 30 +inches in advance of where the first one struck, followed by the hind +feet also, with intervals of time and distance between their several +falls. It is highly probable future experiments will prove these +observations to be invariable in leaping. + +It is highly probable that these photographic investigations, which were +executed with wet collodion plates with exposures not exceeding in some +instances the one five-thousandth part of a second, will dispel many +popular illusions as to gait, and that future and more exhaustive +experiments, with all the advantages of recent chemical discoveries, will +completely unveil to the artist all the visible muscular action of men +and animals during their most rapid movements. + +The employment of automatic apparatus for the purpose of obtaining a +regulated succession of photographic exposures is too recent for its +value to be properly understood, or to be generally used for scientific +experiment; at a future time, the pathologist, the anatomist, and other +explorers for hidden truths will find it indispensable for their complex +investigations. + + +LONDON: PRINTED BY WM. CLOWES AND SONS, LIMITED, STAMFORD STREET AND +CHARING CROSS. + + + + + +End of the Project Gutenberg EBook of The Attitudes of Animals in Motion, by +Eadweard Muybridge + +*** END OF THIS PROJECT GUTENBERG EBOOK THE ATTITUDES OF ANIMALS IN MOTION *** + +***** This file should be named 37743.txt or 37743.zip ***** +This and all associated files of various formats will be found in: + http://www.gutenberg.org/3/7/7/4/37743/ + +Produced by Mark C. Orton, Alex Gam and the Online +Distributed Proofreading Team at http://www.pgdp.net (This +file was produced from images generously made available +by The Internet Archive) + + +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 +http://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 http://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 +http://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 http://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 http://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 checks, online payments and credit card donations. +To donate, please visit: http://pglaf.org/donate + + +Section 5. General Information About Project Gutenberg-tm electronic +works. + +Professor Michael S. Hart is 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: + + http://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. |