summaryrefslogtreecommitdiff
path: root/37957.txt
diff options
context:
space:
mode:
authorRoger Frank <rfrank@pglaf.org>2025-10-14 20:09:11 -0700
committerRoger Frank <rfrank@pglaf.org>2025-10-14 20:09:11 -0700
commit6149ab252e9a0896fb9765bf9a0698dbdd02595b (patch)
tree0ef6b0387cc39769c1d2c753918ce03695536183 /37957.txt
initial commit of ebook 37957HEADmain
Diffstat (limited to '37957.txt')
-rw-r--r--37957.txt24784
1 files changed, 24784 insertions, 0 deletions
diff --git a/37957.txt b/37957.txt
new file mode 100644
index 0000000..d313fc1
--- /dev/null
+++ b/37957.txt
@@ -0,0 +1,24784 @@
+The Project Gutenberg EBook of Man and Nature, by George P. Marsh
+
+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: Man and Nature
+ or, Physical Geography as Modified by Human Action
+
+Author: George P. Marsh
+
+Release Date: November 9, 2011 [EBook #37957]
+
+Language: English
+
+Character set encoding: ASCII
+
+*** START OF THIS PROJECT GUTENBERG EBOOK MAN AND NATURE ***
+
+
+
+
+Produced by Julia Miller and the Online Distributed
+Proofreading Team at http://www.pgdp.net (This file was
+produced from images generously made available by The
+Internet Archive/American Libraries.)
+
+
+
+
+
+
+
+
+
+MAN AND NATURE;
+
+OR,
+
+PHYSICAL GEOGRAPHY
+
+
+AS MODIFIED BY HUMAN ACTION.
+
+
+BY
+
+GEORGE P. MARSH.
+
+
+"Not all the winds, and storms, and earthquakes, and seas, and seasons
+of the world, have done so much to revolutionize the earth as MAN, the
+power of an endless life, has done since the day he came forth upon it,
+and received dominion over it."--H. BUSHNELL, _Sermon on the Power of an
+Endless Life_.
+
+
+NEW YORK:
+
+CHARLES SCRIBNER & CO., No. 654 BROADWAY.
+
+1867.
+
+
+
+
+ENTERED, according to Act of Congress, in the year 1864, by
+
+CHARLES SCRIBNER,
+
+In the Clerk's Office of the District Court of the United States for the
+Southern District of New York.
+
+
+JOHN F. TROW & CO.
+
+PRINTER, STEREOTYPER, AND ELECTROTYPER,
+
+46, 48, & 50 Greene St., New York.
+
+
+
+
+PREFACE.
+
+
+The object of the present volume is: to indicate the character and,
+approximately, the extent of the changes produced by human action in the
+physical conditions of the globe we inhabit; to point out the dangers of
+imprudence and the necessity of caution in all operations which, on a
+large scale, interfere with the spontaneous arrangements of the organic
+or the inorganic world; to suggest the possibility and the importance of
+the restoration of disturbed harmonies and the material improvement of
+waste and exhausted regions; and, incidentally, to illustrate the
+doctrine, that man is, in both kind and degree, a power of a higher
+order than any of the other forms of animated life, which, like him, are
+nourished at the table of bounteous nature.
+
+In the rudest stages of life, man depends upon spontaneous animal and
+vegetable growth for food and clothing, and his consumption of such
+products consequently diminishes the numerical abundance of the species
+which serve his uses. At more advanced periods, he protects and
+propagates certain esculent vegetables and certain fowls and
+quadrupeds, and, at the same time, wars upon rival organisms which prey
+upon these objects of his care or obstruct the increase of their
+numbers. Hence the action of man upon the organic world tends to subvert
+the original balance of its species, and while it reduces the numbers of
+some of them, or even extirpates them altogether, it multiplies other
+forms of animal and vegetable life.
+
+The extension of agricultural and pastoral industry involves an
+enlargement of the sphere of man's domain, by encroachment upon the
+forests which once covered the greater part of the earth's surface
+otherwise adapted to his occupation. The felling of the woods has been
+attended with momentous consequences to the drainage of the soil, to the
+external configuration of its surface, and probably, also, to local
+climate; and the importance of human life as a transforming power is,
+perhaps, more clearly demonstrable in the influence man has thus exerted
+upon superficial geography than in any other result of his material
+effort.
+
+Lands won from the woods must be both drained and irrigated; river banks
+and maritime coasts must be secured by means of artificial bulwarks
+against inundation by inland and by ocean floods; and the needs of
+commerce require the improvement of natural, and the construction of
+artificial channels of navigation. Thus man is compelled to extend over
+the unstable waters the empire he had already founded upon the solid
+land.
+
+The upheaval of the bed of seas and the movements of water and of wind
+expose vast deposits of sand, which occupy space required for the
+convenience of man, and often, by the drifting of their particles,
+overwhelm the fields of human industry with invasions as disastrous as
+the incursions of the ocean. On the other hand, on many coasts, sand
+hills both protect the shores from erosion by the waves and currents,
+and shelter valuable grounds from blasting sea winds. Man, therefore,
+must sometimes resist, sometimes promote, the formation and growth of
+dunes, and subject the barren and flying sands to the same obedience to
+his will to which he has reduced other forms of terrestrial surface.
+
+Besides these old and comparatively familiar methods of material
+improvement, modern ambition aspires to yet grander achievements in the
+conquest of physical nature, and projects are meditated which quite
+eclipse the boldest enterprises hitherto undertaken for the modification
+of geographical surface.
+
+The natural character of the various fields where human industry has
+effected revolutions so important, and where the multiplying population
+and the impoverished resources of the globe demand new triumphs of mind
+over matter, suggests a corresponding division of the general subject,
+and I have conformed the distribution of the several topics to the
+chronological succession in which man must be supposed to have extended
+his sway over the different provinces of his material kingdom. I have,
+then, in the Introductory chapter, stated, in a comprehensive way, the
+general effects and the prospective consequences of human action upon
+the earth's surface and the life which peoples it. This chapter is
+followed by four others in which I have traced the history of man's
+industry as exerted upon Animal and Vegetable Life, upon the Woods,
+upon the Waters, and upon the Sands; and to these I have added a
+concluding chapter upon Probable and Possible Geographical Revolutions
+yet to be effected by the art of man.
+
+I have only to add what, indeed, sufficiently appears upon every page of
+the volume, that I address myself not to professed physicists, but to
+the general intelligence of educated, observing, and thinking men; and
+that my purpose is rather to make practical suggestions than to indulge
+in theoretical speculations properly suited to a different class from
+that to which those for whom I write belong.
+
+ GEORGE P. MARSH.
+
+_December 1, 1863._
+
+
+
+
+BIBLIOGRAPHICAL LIST
+
+OF WORKS CONSULTED IN THE PREPARATION OF THIS VOLUME.
+
+
+_Amersfoordt, J. P._ Het Haarlemmermeer, Oorsprong, Geschiedenis,
+Droogmaking. Haarlem, 1857. 8vo.
+
+_Andresen, C. C._ Om Klitformationen og Klittens Behandling og
+Bestyrelse. Kjoebenhavn, 1861. 8vo.
+
+Annali di Agricoltura, Industria e Commercio. Pubblicati per cura del
+Ministero d'Agricoltura, Industria e Commercio. Fasc i-v. Torino,
+1862-'3. 8vo.
+
+_Arago, F._ Extracts from, in Becquerel, Des Climats.
+
+_Arriani_, Opera. Lipsiae, 1856. 2 vols. 12mo.
+
+_Asbjoernsen, P. Chr._ Om Skovene og om et ordnet Skovbrug i Norge.
+Christiania, 1855. 12mo.
+
+Aus der Natur. Die neuesten Entdeckungen auf dem Gebiete der
+Naturwissenschaften. Leipzig, various years. 20 vols. 8vo.
+
+_Ave-Lallemant, K. C. B._ Die Benutzung der Palmen am Amazonenstrom in
+der Oekonomie der Indier. Hamburg, 1861. 18mo.
+
+_Babinet._ Etudes et Lectures sur les Sciences d'Observation. Paris,
+1855-1863. 7 vols. 18mo.
+
+_Baer, von._ Kaspische Studien. St. Petersburg, 1855-1859. 8vo.
+
+_Barth, Heinrich._ Wanderungen durch die Kuestenlaender des Mittelmeeres.
+V. i. Berlin, 1849. 8vo.
+
+_Barth, J. B._ Om Skovene i deres Forhold til National[oe]conomien.
+Christiania, 1857. 8vo.
+
+_Baude, J. J._ Les Cotes de la Manche, Revue des Deux Mondes, 15
+Janvier, 1859.
+
+_Baumgarten._ Notice sur les Rivieres de la Lombardie; in Annales des
+Ponts et Chaussees, 1847, 1er semestre, pp. 129-199.
+
+_Beckwith, Lieut._ Report in Pacific Railroad Report, vol. ii.
+
+_Becquerel._ Des Climats et de l'Influence qu'exercent les Sols boises
+et non-boises. Paris, 1853. 8vo.
+
+---- Elements de Physique Terrestre et de Meteorologie. Paris, 1847.
+8vo.
+
+_Belgrand._ De l'Influence des Forets sur l'ecoulement des Eaux
+Pluviales; in Annales des Ponts et Chaussees, 1854, 1er semestre, pp. 1,
+27.
+
+_Berg, Edmund von._ Das Verdraengen der Laubwaelder im Noerdlichen
+Deutschlande durch die Fichte und die Kiefer. Darmstadt, 1844. 8vo.
+
+_Bergsoee, A. F._ Greve Ch. Ditlev Frederik Reventlovs Virksomhed som
+Kongens Embedsmand og Statens Borger. Kjoebenhavn, 1837. 2 vols. 8vo.
+
+_Berlepsch, H._ Die Alpen in Natur- und Lebensbildern. Leipzig, 1862.
+8vo.
+
+_Bianchi, Celestino._ Compendio di Geografia Fisica Speciale d'Italia.
+Appendice alla traduzione Italiana della Geog.-Fisica di Maria
+Somerville. Firenze, 1861. (2d vol. of translation.)
+
+_Bigelow, John._ Les Etats Unis d'Amerique en 1863. Paris, 1863. 8vo.
+
+_Blake, Wm. P._ Reports in Pacific Railroad Report, vols. ii and v.
+
+_Blanqui._ Memoire sur les Populations des Hautes Alpes; in Memoires de
+l'Academie des Sciences Morales et Politiques, 1843.
+
+---- Voyage en Bulgarie. Paris, 1843. 12mo.
+
+---- Precis Elementaire d'Economie Politique, suivi du Resume de
+l'Histoire du Commerce et de l'Industrie. Paris, 1857. 12mo.
+
+_Boitel, Amedee._ Mise en valeur des Terres pauvres par le Pin Maritime.
+2d edition. Paris, 1857. 8vo.
+
+_Bonnemere, Eugene._ Histoire des Paysans depuis la fin du Moyen Age
+jusqu'a nos jours. Paris, 1856. 2 vols. 8vo.
+
+_Boettger, C._ Das Mittelmeer. Leipzig, 1859.
+
+_Boussingault, J. B._ Economie Rurale consideree dans ses Rapports avec
+la Chimie, la Physique, et la Meteorologie. 2d edition. Paris, 1851. 2
+vols. 8vo.
+
+_Bremontier, N. T._ Memoire sur les Dunes; in Annales des Ponts et
+Chaussees, 1833, 1er semestre, pp. 145, 223.
+
+_Brincken, J. von den._ Ansichten ueber die Bewaldung der Steppen des
+Europaeischen Russland. Braunschweig, 1854. 4to.
+
+_Buettner, J. G._ Zur Physikalischen Geographie; in Berghaus,
+Geographisches Jahrbuch, No. iv, 1852, pp. 9-19.
+
+_Caimi, Pietro._ Cenni sulla Importanza e Coltura dei Boschi. Milano,
+1857. 8vo.
+
+_Cantegril, and others._ Extracts in Comptes Rendus a l'Academie des
+Sciences. Paris, 1861.
+
+_Castellani._ Dell' immediata influenza delle Selve sul corso delle
+acque. Torino, 1818, 1819. 2 vols. 4to.
+
+Census of the United States for 1860. Preliminary Report on, Washington,
+1862. 8vo.
+
+_Cerini, Giuseppe._ Dell' Impianto e Conservazione dei Boschi. Milano,
+1844. 8vo.
+
+_Champion, Maurice._ Les Inondations en France depuis le VIme Siecle
+jusqu'a nos jours. Paris, 1858, 1862. Vols. i-iv, 8vo.
+
+_Chateauvieux, F. Lullin de._ Lettres sur l'Italie. Seconde edition,
+Geneve, 1834. 8vo.
+
+_Chevandier._ Extracts in Comptes Rendus a l'Academie des Sciences.
+Juillet-Decembre, 1844. Paris.
+
+_Clave, Jules._ Etudes sur l'Economie Forestiere. Paris, 1862. 12mo.
+
+---- La Foret de Fontainebleau; Revue des Deux Mondes, 1 Mai, 1863.
+
+_Cooper, J. G._ The Forests and Trees of Northern America; in Report of
+the Commissioner of Patents for the year 1860, pp. 416-445.
+
+_Cotta, Bernhard._ Deutschlands Boden. Leipzig, 1858. 2 vols. 8vo.
+
+---- Vorwort zu Paramelle's Quellenkunde. See _Paramelle_.
+
+---- Die Alpen. Leipzig, 1851. 8vo.
+
+_Coultas, Harland._ What may be Learned from a Tree. New York, 1860.
+8vo.
+
+_Courier, Paul-Louis._ [OE]uvres Completes. Bruxelles, 1833. 8vo.
+
+_Dana, James D._ Manual of Geology. Philadelphia, 1863. 8vo.
+
+_Delamarre, L. G._ Historique de la Creation d'une Richesse Millionaire
+par la culture des Pins. Paris, 1827. 8vo.
+
+_D. Hericourt, A. F._ Les Inondations et le livre de M. Valles; Annales
+Forestieres, December, 1857, pp. 310, 321. Paris.
+
+_Diggelen, B. P. G. van._ Groote Werken in Nederland. Zwolle, 1855. 8vo.
+
+_Dumas, M. J._ La Science des Fontaines. 2me edition, Paris, 1857. 8vo.
+
+_Dumont, Aristide._ Des Travaux Publics dans leurs Rapports avec
+l'Agriculture. Paris, 1847. 8vo.
+
+_Dwight, Timothy._ Travels in New England and New York. New Haven, 1821.
+4 vols. 8vo.
+
+_Emerson, George B._ A Report on the Trees and Shrubs growing naturally
+in Massachusetts. Boston, 1850. 8vo.
+
+_Emory, Wm. H., Col._ Report of Commissioners of the United States and
+Mexican Boundary Survey, vol. i, 1857.
+
+_Escourrou-Miliago, A._ L'Italie a propos de l'Exposition Universelle de
+Paris. Paris, 1856. 8vo.
+
+_Evelyn, John._ Silva; or, a Discourse of Forest Trees. With Notes by A.
+Hunter. York, 1786. 2 vols. 4to.
+
+---- Terra, a Philosophical Discourse of Earth. York, 1786. 4to. in vol.
+ii of Silva.
+
+_Feraud-Giraud, L. J. D._ Police des Bois, Defrichements et Reboisements
+Commentaire pratique sur les lois promulguees en 1859 et 1860. Paris,
+1861. 8vo.
+
+_Ferrara, Francesco._ Descrizione dell' Etna. Palermo, 1818. 8vo.
+
+_Feuillide, C. de._ L'Algerie Francaise. Paris, 1856. 8vo.
+
+_Figuier, Louis._ L'Annee Scientifique et Industrielle. Paris, 1862-'3.
+12mo.
+
+Finnboga Saga hins rama. Kaupmannahoefn, 1812. 4to.
+
+_Foissac, P._ Meteorologie mit Ruecksicht auf die Lehre vom Kosmos,
+Deutsch von A. H. Emsmann. Leipzig, 1859. 8vo.
+
+_Forchhammer, G._ Geognostische Studien am Meeres-Ufer; in Leonhard und
+Bronn's Neues Jahrbuch fuer Mineralogie, Geognosie, Geologie, etc.
+Jahrgang, 1841, pp. 1-38.
+
+_Fossombroni, Vittorio._ Memorie Idraulico-Storiche sopra la
+Val-di-Chiana. Montepulciano, 3za edizione, 1835. 8vo.
+
+_Fraas, C._ Klima und Pflanzenwelt in der Zeit. Landshut, 1847. 8vo.
+
+_Frisi, Paolo._ Del Modo di regolare i Fiumi e i Torrenti. Lucca, 1762.
+4to.
+
+_Fuller, Thomas._ The History of the Worthies of England. London, 1662.
+Folio.
+
+_Gilliss, J. M., Capt._ United States Naval Astronomical Expedition to
+the Southern Hemisphere. Washington, 1855. 2 vols. 4to.
+
+_Giorgini._ Paper by; in Salvagnoli-Marchetti, Rapporto sul
+Bonificamento delle Maremme, App. v.
+
+_Girard et Parent-Duchatelet._ Rapport sur les Puits fores dits
+Artesiens; Annales des Ponts et Chaussees, 1833, 2me semestre, 313-344.
+
+_Graham, J. D., Lieut.-Col._ A Lunar Tidal Wave in the North American
+Lakes demonstrated. Cambridge, 1861. 8vo. _pamphlet_. Also in vol. xiv,
+Proc. Am. Ass. for Adv. of Science for 1860.
+
+_Hakluyt, Richard._ The Principal Navigations, Voyages, &c., of the
+English Nation. London, 1598-'9. 3 vols. folio.
+
+_Harrison, W._ An Historicall Description of the Iland of Britaine; in
+Holinshed's Chronicles. Reprint of 1807, vol. i.
+
+_Hartwig, G._ Das Leben des Meeres. Frankfurt, 1857. 8vo.
+
+_Haxthausen, August von._ Transkaukasia. Leipzig, 1856. 2 vols. 8vo.
+
+_Henry, Prof. Joseph._ Paper on Meteorology in its connection with
+Agriculture; in United States Patent Office Report for 1857, pp.
+419-550.
+
+_Herschel, Sir J. F. W._ Physical Geography. Edinburgh, 1861. 12mo.
+
+_Heyer, Gustav._ Das Verhalten der Waldbaeume gegen Licht und Schatten.
+Erlangen, 1852. 8vo.
+
+_Hohenstein, Adolph._ Der Wald sammt dessen wichtigem Einfluss auf das
+Klima, &c. Wien, 1860. 8vo.
+
+_Humboldt, Alexander von._ Ansichten der Natur. Dritte Ausgabe,
+Stuttgart und Tuebingen, 1849. 2 vols. 12mo.
+
+_Hummel, Karl._ Physische Geographie. Graz, 1855. 8vo.
+
+_Hunter, A._ Notes to Evelyn, Silva, and Terra. York, 1786. See
+_Evelyn_.
+
+_Jacini, Stefano._ La Proprieta Fondiaria e le Popolazioni agricole in
+Lombardia. Milano e Verona, 1857. 8vo.
+
+_Joinville._ Histoire de Saint-Louis. Nouvelle Collection des Memoires
+pour servir a l'Histoire de France, par Michaud et Poujoulat. Tome i.
+Paris, 1836. 8vo.
+
+_Josselyn, John._ New England Rarities. London, 1672. 12mo.
+
+_Knorr, E. A._ Studien ueber die Buchen-Wirthschaft. Nordhausen, 1863.
+8vo.
+
+_Kohl, J. G._ Alpenreisen. Dresden und Leipzig, 1849. 3 vols. 8vo.
+
+---- Die Marschen und Inseln der Herzogthuemer Schleswig und Holstein.
+Dresden und Leipzig, 1846. 3 vols. 8vo.
+
+_Kramer, Gustav._ Der Fuciner-See. Berlin, 1839. 4to.
+
+_Krause, G. C. A._ Der Duenenbau auf den Ostsee-Kuesten West-Preussens.
+1850. 8vo.
+
+_Kremer, Alfred von._ AEgypten, Forschungen ueber Land und Volk. Leipzig,
+1863. 2 vols. 8vo.
+
+_Kriegk, G. L._ Schriften zur allgemeinen Erdkunde. Leipzig, 1840. 8vo.
+
+_Ladoucette, J. C. F._ Histoire, Topographie, Antiquites, Usages,
+Dialectes des Hautes Alpes. Seconde edition, 1834. 1 vol. 8vo. and
+Atlas.
+
+_Lastadius, Lars Levi._ Om Moejligheten och Foerdelen af allmaenna
+Uppodlingar i Lappmarken. Stockholm, 1824. 12mo.
+
+_Laestadius, Petrus._ Journal foer foersta aret af hans Tjenstgoering sasom
+Missionaire i Lappmarken. Stockholm, 1831. 8vo.
+
+---- Fortsaettning af Journalen oefver Missions-Resor i Lappmarken.
+Stockholm, 1833. 8vo.
+
+_Lampridius._ Vita Elagabali in Script. Hist., August.
+
+_Landgrebe, Georg._ Naturgeschichte der Vulcane. Gotha, 1855. 2 vols.
+8vo.
+
+_Laurent, Ch._ Memoires sur le Sahara Oriental au point de vue des Puits
+Artesiens. Paris, 1859. 8vo. _pamphlet_. Also, in Mem de la Soc. des
+Ingenieurs Civils, and the Bulletin de la Soc. Geologique de France.
+
+_Laval._ Memoire sur les Dunes du Golfe de Gascogne; in Annales des
+Ponts et Chaussees, 1847, 2me semestre, pp. 218-268.
+
+_Lavergne, M. L. de._ Economie Rurale de la France, depuis 1789. 2me
+edition, Paris, 1861. 12mo.
+
+Le Alpi che cingono l'Italia. Parte 1er, vol. 1er. Torino, 1845. 8vo.
+
+_Lefort._ Notice sur les travaux de Fixation des Dunes; in Annales des
+Ponts et Chaussees, 1831, 2me semestre, pp. 320-332.
+
+_Lenormant._ Note relative a l'Execution d'un Puits Artesien en
+Egypte sous la XVIII^{me} Dynastie; Academie des Inscriptions et
+Belles-Lettres, 12 Novembre, 1852.
+
+Liber Albus: The White Book of the City of London. London, 1861. 4to.
+
+_Loftus, W. K._ Travels and Researches in Chaldaea and Susiana. New York,
+1857. 8vo.
+
+_Lombardini._ Cenni Idrografi sulla Lombardia; Intorno al Sistema
+Idraulico del Po; epitomized by Baumgarten in Annales des Ponts et
+Chaussees, 1847, 1er semestre, pp. 129, 199; and in Dumont, Des Travaux
+Publics, pp. 268, 335.
+
+---- Sui progetti intesi ad estendere l'irrigazione della Pianura del
+Po. Politecnico. Gennajo, 1863, pp. 5-50.
+
+_Lorentz._ Cours Elementaire de Culture des Bois, complete et publie par
+A. Parade, 4me edition. Paris et Nancy, 1860. 8vo.
+
+_Lyell, Sir Charles._ The Geological Evidence of the Antiquity of Man.
+London, 1863. 8vo. Principles of Geology. New York, 1862. 8vo.
+
+_Mardigny, M. de._ Memoire sur les Inondations des Rivieres de
+l'Ardeche. Paris, 1860. 8vo.
+
+_Marschand, A._ Ueber die Entwaldung der Gebirge. Bern, 1849. 12mo.
+_pamphlet_.
+
+_Martineau._ Endeavors after the Christian Life. Boston, 1858.
+
+_Martins._ Revue des Deux Mondes, Avril, 1863.
+
+_Maury, M. F._ The Physical Geography of the Sea. Tenth edition. London,
+1861. 8vo.
+
+_Medlicott, Dr._ Observations of, quoted from London Athenaeum, 1863.
+
+_Meguscher, Francesco._ Memorie sulla migliore maniera per rimettere i
+Boschi della Lombardia, etc. Milano, 1859. 8vo.
+
+_Mejdell, Th._ Om Foranstaltninger til Behandling af Norges Skove.
+Christiania, 1858. 8vo.
+
+_Mella._ Delle Inondazioni del Mella nella notto del 14 al 15 Agosto,
+1850. Brescia, 1851. 8vo.
+
+_Meyer, J._ Physik der Schweiz. Leipzig, 1854. 8vo.
+
+_Michelet, J._ L'Insecte, 4me edition. Paris, 1860. 12mo.
+
+---- L'Oiseau, 7me edition. Paris, 1861. 12mo.
+
+_Monestier-Savignat, A._ Etude sur les Phenomenes, l'Amenagement et la
+Legislation des Eaux au point de vue des Inondations. Paris, 1858. 8vo.
+
+_Montluisant._ Note sur les Dessechements, les Endiguements et les
+Irrigations; in Annales des Ponts et Chaussees, 1833, 2me semestre, pp.
+281-294.
+
+_Morozzi, Ferdinando._ Dello Stato Antico e Moderno del Fiume Arno.
+Firenze, 1762. 4to.
+
+_Mueller, K._ Das Buch der Pflanzenwelt. Leipzig, 1857. 2 vols. 12mo.
+
+_Nangis, Guillaume de._ Extracts from, in Nouvelle Collection des
+Memoires pour servir par Michaud et Poujoulat. Vol. i. Paris, 1836.
+
+_Nanquette, Henri._ Cours d'Amenagement des Forets. Paris et Nancy,
+1860. 8vo.
+
+_Newberry, Dr._ Report in Pacific Railroad Report, vol. vi.
+
+Niebelunge-Lied, Der. Abdruck der Handschrift von Joseph von Lassberg.
+Leipzig, 1840. Folio.
+
+_Niel._ L'Agriculture des Etats Sardes. Turin, 1857. 8vo.
+
+Pacific Railroad Report. Reports of Explorations and Surveys for a
+Railroad Route to the Pacific. Washington, various years. 12 vols. 4to.
+
+_Palissy, Bernard._ [OE]uvres Completes, avec des Notes, etc., par
+Paul-Antoine Cap. Paris, 1844. 12mo.
+
+_Parade, A._ See _Lorentz_.
+
+_Paramelle, Abbe._ Quellenkunde, Lehre von der Bildung und Auffindung
+der Quellen; mit einem Vorwort von B. Cotta. Leipzig, 1856. 12mo.
+
+_Parish, Dr._ Life of Dr. Eleazer Wheelock. 8vo.
+
+_Parry, C. C._ Report in United States and Mexican Boundary Survey, vol.
+i.
+
+_Parthey, G._ Wanderungen durch Sicilien und die Levante. Berlin, 1834.
+2 vols. 12mo.
+
+_Piper, R. U._ The Trees of America. Boston, 1858, Nos. i-iv. 4to.
+
+_Plinii, Historia Naturalis_, ed. Hardouin. Paris, 1723. 3 vols. folio.
+
+_Ponz, Antonio._ Viage de Espana. Madrid, 1788, etc. 18 vols. 12mo.
+
+_Quatrefages, A. de._ Souvenirs d'un Naturaliste. Paris, 1854. 2 vols.
+12mo.
+
+_Reclus, Elisee._ Le Littoral de la France; Revue des Deux Mondes, 15
+Decembre, 1862.
+
+_Rentzsch, Hermann._ Der Wald im Haushalt der Natur und der
+Volkswirthschaft. Leipzig, 1862. 8vo.
+
+_Ribbe, Charles de_. La Provence au point de vue des Bois, des Torrents
+et des Inondations. Paris, 1857. 8vo.
+
+_Ridolfi, Cosimo._ Lezioni Orali. Firenze, 1862. 2 vols. 8vo.
+
+_Ritter, Carl._ Einleitung zur allgemeinen vergleichenden Geographie.
+Berlin, 1852. 8vo.
+
+---- Die Erdkunde im Verhaeltniss zur Natur und zur Geschichte des
+Menschen. Berlin, various years. 19 vols. 8vo.
+
+_Rosa, G._ Le Condizioni de' boschi, de' fiumi e de' torrenti nella
+provincia di Bergamo. Politecnico, Dicembre, 1861, pp. 606, 621.
+
+---- Studii sui Boschi. Politecnico, Maggio, 1862, pp. 232, 238.
+
+_Rossmaessler, C. A._ Der Wald. Leipzig und Heidelberg, 1863. 8vo.
+
+_Roth, J._ Der Vesuv und die Umgebung von Neapel. Berlin, 1857. 8vo.
+
+_Rozet, M._ Moyens de forcer les Torrents des Montagnes de rendre une
+partie du sol qu'ils ravagent. Paris, 1856. 8vo. _pamphlet_.
+
+_Salvagnoli-Marchetti, Antonio._ Memorie Economico-Statistiche sulle
+Maremme Toscane. Firenze, 1846. 8vo.
+
+---- Raccolta di Documenti sul Bonificamento delle Maremmo Toscane.
+Firenze, 1861. 8vo.
+
+---- Rapporto sul Bonificamento delle Maremmo Toscane. Firenze, 1859.
+8vo.
+
+---- Rapporto sulle Operazioni Idrauliche ed Economiche eseguite nel
+1859-'60 nelle Maremmo Toscane. Firenze, 1860. 8vo.
+
+_Sandys, George._ A Relation of a Journey begun An. Dom. 1610. London,
+1627. Folio.
+
+_Schacht, H._ Les Arbres, Etudes sur leur Structure et leur Vegetation,
+traduit par E. Morren. Bruxelles et Leipzig, 1862. 8vo.
+
+_Schleiden, M. J._ Die Landenge von Sues. Leipzig, 1858. 8vo.
+
+---- Die Pflanze und ihr Leben. Leipzig, 1848. 8vo.
+
+_Schubert, W. von._ Resa genom Sverige, Norrige, Lappland, etc.
+Stockholm, 1823. 3 vols. 8vo.
+
+_Seneca, L. A._ Opera Omnia quae supersunt, ex rec. Ruhkopf. Aug.
+Taurinorum, 1831. 6 vols. 8vo.
+
+_Simonde, J. E. L._ Tableau de l'Agriculture Toscane. Geneve, 1801. 8vo.
+
+_Smith, Dr. William._ A Dictionary of the Bible. London, 1860. 3 vols.
+8vo.
+
+---- A Dictionary of Greek and Roman Geography. London, 1854, 1857. 2
+vols. 8vo.
+
+_Smith, John._ Historie of Virginia. London, 1624. Folio.
+
+_Somerville, Mary._ Physical Geography. Fifth edition. London, 1862.
+12mo.
+
+_Springer, John S._ Forest-Life and Forest-Trees. New York, 1851. 12mo.
+
+_Stanley, Dr._ Lectures on the History of the Jewish Church. London,
+1863. 8vo.
+
+_Staring, W. H._ De Bodem van Nederland. Haarlem, 1856. 2 vols. 8vo.
+
+---- Voormaals en Thans. Haarlem, 1858. 8vo.
+
+_Stevens, Gov._ Report in Pacific Railroad Report, vol. xii.
+
+_Strain, Lieut. I. C._ Darien Exploring Expedition, by J. T. Headley, in
+Harper's Magazine. New York, March, April, and May, 1855.
+
+_Streffleur, V._ Ueber die Natur und die Wirkungen der Wildbaeche. Sitz.
+Ber. der M. N. W. Classe der Kaiserl. Akad. der Wis. February, 1852,
+viii, p. 248.
+
+_Stroem, Isr._ Om Skogarnas Vard och Skoetsel. Upsala, 1853. _Pamphlet._
+
+_Surell, Alexandre._ Etude sur les Torrents des Hautes Alpes. Paris,
+1844. 4to.
+
+_Tartini, Ferdinando._ Memorie sul Bonificamento delle Maremme Toscane.
+Firenze, 1838. Folio.
+
+_Thomas and Baldwin._ Gazetteer. Philadelphia, 1855. 1 vol. 8vo.
+
+_Thompson, Z._ History of Vermont, Natural, Civil, and Statistical.
+Burlington, 1842. 8vo.
+
+---- Appendix to History of Vermont. Burlington, 1853. 8vo.
+
+_Titcomb, Timothy._ Lessons in Life. New York, 1861. 12mo.
+
+_Treadwell, Dr._ Observations of, quoted from Report of Commissioner of
+Patents.
+
+_Troy, Paul._ Etude sur le Reboisement des Montagnes. Paris et Toulouse,
+1861. 8vo. _pamphlet_.
+
+_Tschudi, Friedrich von._ Ueber die Landwirthschaftliche Bedeutung der
+Voegel. St. Gallen, 1854. 12mo.
+
+_Tschudi, J. J. von._ Travels in Peru. New York, 1848. 8vo.
+
+_Valles, M. F._ Etudes sur les Inondations, leurs causes et leurs
+effets. Paris, 1857. 8vo.
+
+_Valvasor, Johann Weichard._ Die Ehre des Herzogthums Crain. Laybach,
+1689. 4 vols. folio.
+
+_Van Lennep._ Extracts from Journal of, in the Missionary Herald.
+
+_Vaupell, Chr._ Boegens Indvandring i de Danske Skove. Kjoebenhavn, 1857.
+8vo.
+
+---- De Nordsjaellandske Skovmoser. Kjoebenhavn, 1851. 4to. _pamphlet_.
+
+_Venema, G. A._ Over het Dalen van de Noordelijke Kuststreken van ons
+Land. Groningen, 1854. 8vo.
+
+_Villa, Antonio Giovanni Batt._ Necessita dei Boschi nella Lombardia.
+Milano, 1850. 4to.
+
+_Viollet, J. B._ Theorie des Puits Artesiens. Paris, 1840. 8vo.
+
+_Walterhausen, W. Sartorius von._ Ueber den Sicilianischen Ackerbau.
+Goettingen, 1863.
+
+_Webster, Noah._ A Collection of Papers on Political, Literary, and
+Moral Subjects. New York, 1843. 8vo.
+
+_Wessely, Joseph._ Die Oesterreichischen Alpenlaender und ihre Forste.
+Wien, 1853. 2 vols. 8vo.
+
+_Wetzstein, J. G._ Reisebericht ueber Hauran und die Trachonen. Berlin,
+1860. 8vo.
+
+_Wild, Albert._ Die Niederlande. Leipzig, 1862. 2 vols. 8vo.
+
+_Wilhelm, Gustav._ Der Boden und das Wasser. Wien, 1861. 8vo.
+
+_Williams, Dr._ History of Vermont. 2 vols. 8vo.
+
+_Wittwer, W. C._ Die Physikalische Geographie. Leipzig, 1855. 8vo.
+
+_Young, Arthur._ Voyages en France, pendant les annees 1787, 1788, 1789,
+precedee d'une introduction par Lavergne. Paris, 1860. 2 vols. 12mo.
+
+---- Voyages en Italie et en Espagne, pendant les annees 1787, 1789.
+Paris, 1860. 1 vol. 12mo.
+
+
+
+
+TABLE OF CONTENTS.
+
+
+CHAPTER I.
+
+INTRODUCTORY.
+
+ Natural Advantages of the Territory of the Roman Empire--Physical
+ Decay of that Territory and of other parts of the Old World--
+ Causes of the Decay--New School of Geographers--Reaction of
+ Man upon Nature--Observation of Nature--Cosmical and Geological
+ Influences--Geographical Influence of Man--Uncertainty of our
+ Meteorological Knowledge--Mechanical Effects produced by Man on
+ the surface of the Earth--Importance and Possibility of Physical
+ Restoration--Stability of Nature--Restoration of Disturbed
+ Harmonies--Destructiveness of Man--Physical Improvement--Human
+ and Brute Action Compared--Forms and Formations most liable to
+ Physical Degradation--Physical Decay of New Countries--Corrupt
+ Influence of Private Corporations, _Note_, 1
+
+
+CHAPTER II.
+
+TRANSFER, MODIFICATION, AND EXTIRPATION OF VEGETABLE AND OF ANIMAL
+SPECIES.
+
+ Modern Geography embraces Organic Life--Transfer of Vegetable
+ Life--Foreign Plants grown in the United States--American
+ Plants grown in Europe--Modes of Introduction of Foreign
+ Plants--Vegetables, how affected by transfer to Foreign
+ Soils--Extirpation of Vegetables--Origin of Domestic Plants--
+ Organic Life as a Geological and Geographical Agency--Origin
+ and Transfer of Domestic Animals--Extirpation of Animals--
+ Numbers of Birds in the United States--Birds as Sowers and
+ Consumers of Seeds, and as Destroyers of Insects--Diminution
+ and Extirpation of Birds--Introduction of Birds--Utility of
+ Insects and Worms--Introduction of Insects--Destruction of
+ Insects--Reptiles--Destruction of Fish--Introduction and
+ Breeding of Fish--Extirpation of Aquatic Animals--Minute
+ Organisms, 57
+
+
+CHAPTER III.
+
+THE WOODS.
+
+ The Habitable Earth originally Wooded--The Forest does not
+ furnish Food for Man--First Removal of the Woods--Effects
+ of Fire on Forest Soil--Effects of the Destruction of the
+ Forest--Electrical Influence of Trees--Chemical Influence
+ of the Forest.
+
+ Influence of the Forest, considered as Inorganic Matter, on
+ Temperature: _a_, Absorbing and Emitting Surface; _b_, Trees
+ as Conductors of Heat; _c_, Trees in Summer and in Winter;
+ _d_, Dead Products of Tree; _e_, Trees as a Shelter to Grounds
+ to the leeward of them; _f_, Trees as a Protection against
+ Malaria--The Forest, as Inorganic Matter, tends to mitigate
+ extremes.
+
+ Trees as Organisms: Specific Temperature--Total Influence of
+ the Forest on Temperature.
+
+ Influence of Forests on the Humidity of the Air and the Earth:
+ _a_, as Inorganic Matter; _b_, as Organic--Wood Mosses and
+ Fungi--Flow of Sap--Absorption and Exhalation of Moisture by
+ Trees--Balance of Conflicting Influences--Influence of the
+ Forest on Temperature and Precipitation--Influence of the
+ Forest on the Humidity of the Soil--Its Influence on the Flow
+ of Springs--General Consequences of the Destruction of the
+ Woods--Literature and Condition of the Forest in different
+ Countries--The Influence of the Forest on Inundations--
+ Destructive Action of Torrents--The Po and its Deposits--
+ Mountain Slides--Protection against the Fall of Rocks and
+ Avalanches by Trees--Principal Causes of the Destruction of
+ the Forest--American Forest Trees--Special Causes of the
+ Destruction of European Woods--Royal Forests and Game Laws--
+ Small Forest Plants, Vitality of Seeds--Utility of the
+ Forest--The Forests of Europe--Forests of the United States
+ and Canada--The Economy of the Forest--European and American
+ Trees Compared--Sylviculture--Instability of American Life, 128
+
+
+CHAPTER IV.
+
+THE WATERS.
+
+ Land artificially won from the Waters: _a_, Exclusion of the Sea
+ by Diking; _b_, Draining of Lakes and Marshes; _c_, Geographical
+ Influence of such Operations--Lowering of Lakes--Mountain Lakes--
+ Climatic Effects of Draining Lakes and Marshes.
+
+ Geographical and Climatic Effects of Aqueducts, Reservoirs,
+ and Canals--Surface and Underdraining, and their Climatic and
+ Geographical Effects--Irrigation and its Climatic and Geographical
+ Effects.
+
+ Inundations and Torrents: _a_, River Embankments; _b_, Floods of
+ the Ardeche; _c_, Crushing Force of Torrents; _d_, Inundations of
+ 1856 in France; _e_, Remedies against Inundations--Consequences
+ if the Nile had been confined by Lateral Dikes.
+
+ Improvements in the Val di Chiana--Improvements in the Tuscan
+ Maremme--Obstruction of River Mouths--Subterranean Waters--
+ Artesian Wells--Artificial Springs--Economizing Precipitation, 330
+
+
+CHAPTER V.
+
+THE SANDS.
+
+ Origin of Sand--Sand now carried down to the Sea--The Sands of
+ Egypt and the adjacent Desert--The Suez Canal--The Sands of
+ Egypt--Coast Dunes and Sand Plains--Sand Banks--Dunes on Coast of
+ America--Dunes of Western Europe--Formation of Dunes--Character of
+ Dune Sand--Interior Structure of Dunes--Form of Dunes--Geological
+ Importance of Dunes--Inland Dunes--Age, Character, and Permanence
+ of Dunes--Use of Dunes as Barrier against the Sea--Encroachments
+ of the Sea--The Luemfjord--Encroachments of the Sea--Drifting
+ of Dune Sands--Dunes of Gascony--Dunes of Denmark--Dunes of
+ Prussia--Artificial Formation of Dunes--Trees suitable for Dune
+ Plantations--Extent of Dunes in Europe--Dune Vineyards of Cape
+ Breton--Removal of Dunes--Inland Sand Plains--The Landes of
+ Gascony--The Belgian Campine--Sands and Steppes of Eastern
+ Europe--Advantages of Reclaiming Dunes--Government Works of
+ Improvement, 451
+
+
+CHAPTER VI.
+
+PROJECTED OR POSSIBLE GEOGRAPHICAL CHANGES BY MAN.
+
+ Cutting of Marine Isthmuses--The Suez Canal--Canal across Isthmus
+ of Darien--Canals to the Dead Sea--Maritime Canals in Greece--
+ Canal of Saros--Cape Cod Canal--Diversion of the Nile--Changes
+ in the Caspian--Improvements in North American Hydrography--
+ Diversion of the Rhine--Draining of the Zuiderzee--Waters of
+ the Karst--Subterranean Waters of Greece--Soil below Rock--
+ Covering Rocks with Earth--Wadies of Arabia Petraea--Incidental
+ Effects of Human Action--Resistance to great Natural Forces--
+ Effects of Mining--Espy's Theories--River Sediment--Nothing
+ small in Nature, 517
+
+
+
+
+CHAPTER I.
+
+INTRODUCTORY.
+
+NATURAL ADVANTAGES OF THE TERRITORY OF THE ROMAN EMPIRE--PHYSICAL
+DECAY OF THAT TERRITORY AND OF OTHER PARTS OF THE OLD WORLD--CAUSES
+OF THE DECAY--NEW SCHOOL OF GEOGRAPHERS--REACTION OF MAN UPON NATURE--
+OBSERVATION OF NATURE--COSMICAL AND GEOLOGICAL INFLUENCES--GEOGRAPHICAL
+INFLUENCE OF MAN--UNCERTAINTY OF OUR METEOROLOGICAL KNOWLEDGE--
+MECHANICAL EFFECTS PRODUCED BY MAN ON THE SURFACE OF THE EARTH--
+IMPORTANCE AND POSSIBILITY OF PHYSICAL RESTORATION--STABILITY OF
+NATURE--RESTORATION OF DISTURBED HARMONIES--DESTRUCTIVENESS OF MAN--
+PHYSICAL IMPROVEMENT--HUMAN AND BRUTE ACTION COMPARED--FORMS AND
+FORMATIONS MOST LIABLE TO PHYSICAL DEGRADATION--PHYSICAL DECAY OF NEW
+COUNTRIES--CORRUPT INFLUENCE OF PRIVATE CORPORATIONS, _note_.
+
+
+_Natural Advantages of the Territory of the Roman Empire._
+
+The Roman Empire, at the period of its greatest expansion, comprised the
+regions of the earth most distinguished by a happy combination of
+physical advantages. The provinces bordering on the principal and the
+secondary basins of the Mediterranean enjoyed a healthfulness and an
+equability of climate, a fertility of soil, a variety of vegetable and
+mineral products, and natural facilities for the transportation and
+distribution of exchangeable commodities, which have not been possessed
+in an equal degree by any territory of like extent in the Old World or
+the New. The abundance of the land and of the waters adequately supplied
+every material want, ministered liberally to every sensuous enjoyment.
+Gold and silver, indeed, were not found in the profusion which has
+proved so baneful to the industry of lands richer in veins of the
+precious metals; but mines and river beds yielded them in the spare
+measure most favorable to stability of value in the medium of exchange,
+and, consequently, to the regularity of commercial transactions. The
+ornaments of the barbaric pride of the East, the pearl, the ruby, the
+sapphire, and the diamond--though not unknown to the luxury of a people
+whose conquests and whose wealth commanded whatever the habitable world
+could contribute to augment the material splendor of their social
+life--were scarcely native to the territory of the empire; but the
+comparative rarity of these gems in Europe, at somewhat earlier periods,
+was, perhaps, the very circumstance that led the cunning artists of
+classic antiquity to enrich softer stones with engravings, which invest
+the common onyx and carnelian with a worth surpassing, in cultivated
+eyes, the lustre of the most brilliant oriental jewels.
+
+Of these manifold blessings the temperature of the air, the distribution
+of the rains, the relative disposition of land and water, the plenty of
+the sea, the composition of the soil, and the raw material of some of
+the arts, were wholly gratuitous gifts. Yet the spontaneous nature of
+Europe, of Western Asia, of Libya, neither fed nor clothed the civilized
+inhabitants of those provinces. Every loaf was eaten in the sweat of the
+brow. All must be earned by toil. But toil was nowhere else rewarded by
+so generous wages; for nowhere would a given amount of intelligent labor
+produce so abundant, and, at the same time, so varied returns of the
+good things of material existence. The luxuriant harvests of cereals
+that waved on every field from the shores of the Rhine to the banks of
+the Nile, the vines that festooned the hillsides of Syria, of Italy, and
+of Greece, the olives of Spain, the fruits of the gardens of the
+Hesperides, the domestic quadrupeds and fowls known in ancient rural
+husbandry--all these were original products of foreign climes,
+naturalized in new homes, and gradually ennobled by the art of man,
+while centuries of persevering labor were expelling the wild vegetation,
+and fitting the earth for the production of more generous growths.
+
+Only for the sense of landscape beauty did unaided nature make
+provision. Indeed, the very commonness of this source of refined
+enjoyment seems to have deprived it of half its value; and it was only
+in the infancy of lands where all the earth was fair, that Greek and
+Roman humanity had sympathy enough with the inanimate world to be alive
+to the charms of rural and of mountain scenery. In later generations,
+when the glories of the landscape had been heightened by plantation, and
+decorative architecture, and other forms of picturesque improvement, the
+poets of Greece and Rome were blinded by excess of light, and became, at
+last, almost insensible to beauties that now, even in their degraded
+state, enchant every eye, except, too often, those which a lifelong
+familiarity has dulled to their attractions.
+
+
+_Physical Decay of the Territory of the Roman Empire, and of other parts
+of the Old World._
+
+If we compare the present physical condition of the countries of which I
+am speaking, with the descriptions that ancient historians and
+geographers have given of their fertility and general capability of
+ministering to human uses, we shall find that more than one half of
+their whole extent--including the provinces most celebrated for the
+profusion and variety of their spontaneous and their cultivated
+products, and for the wealth and social advancement of their
+inhabitants--is either deserted by civilized man and surrendered to
+hopeless desolation, or at least greatly reduced in both productiveness
+and population. Vast forests have disappeared from mountain spurs and
+ridges; the vegetable earth accumulated beneath the trees by the decay
+of leaves and fallen trunks, the soil of the alpine pastures which
+skirted and indented the woods, and the mould of the upland fields, are
+washed away; meadows, once fertilized by irrigation, are waste and
+unproductive, because the cisterns and reservoirs that supplied the
+ancient canals are broken, or the springs that fed them dried up; rivers
+famous in history and song have shrunk to humble brooklets; the willows
+that ornamented and protected the banks of the lesser watercourses are
+gone, and the rivulets have ceased to exist as perennial currents,
+because the little water that finds its way into their old channels is
+evaporated by the droughts of summer, or absorbed by the parched earth,
+before it reaches the lowlands; the beds of the brooks have widened into
+broad expanses of pebbles and gravel, over which, though in the hot
+season passed dryshod, in winter sealike torrents thunder; the entrances
+of navigable streams are obstructed by sandbars, and harbors, once marts
+of an extensive commerce, are shoaled by the deposits of the rivers at
+whose mouths they lie; the elevation of the beds of estuaries, and the
+consequently diminished velocity of the streams which flow into them,
+have converted thousands of leagues of shallow sea and fertile lowland
+into unproductive and miasmatic morasses.
+
+Besides the direct testimony of history to the ancient fertility of the
+regions to which I refer--Northern Africa, the greater Arabian
+peninsula, Syria, Mesopotamia, Armenia and many other provinces of Asia
+Minor, Greece, Sicily, and parts of even Italy and Spain--the multitude
+and extent of yet remaining architectural ruins, and of decayed works of
+internal improvement, show that at former epochs a dense population
+inhabited those now lonely districts. Such a population could have been
+sustained only by a productiveness of soil of which we at present
+discover but slender traces; and the abundance derived from that
+fertility serves to explain how large armies, like those of the ancient
+Persians, and of the Crusaders and the Tartars in later ages, could,
+without an organized commissariat, secure adequate supplies in long
+marches through territories which, in our times, would scarcely afford
+forage for a single regiment.
+
+It appears, then, that the fairest and fruitfulest provinces of the
+Roman Empire, precisely that portion of terrestrial surface, in short,
+which, about the commencement of the Christian era, was endowed with the
+greatest superiority of soil, climate, and position, which had been
+carried to the highest pitch of physical improvement, and which thus
+combined the natural and artificial conditions best fitting it for the
+habitation and enjoyment of a dense and highly refined and cultivated
+population, is now completely exhausted of its fertility, or so
+diminished in productiveness, as, with the exception of a few favored
+oases that have escaped the general ruin, to be no longer capable of
+affording sustenance to civilized man. If to this realm of desolation we
+add the now wasted and solitary soils of Persia and the remoter East,
+that once fed their millions with milk and honey, we shall see that a
+territory larger than all Europe, the abundance of which sustained in
+bygone centuries a population scarcely inferior to that of the whole
+Christian world at the present day, has been entirely withdrawn from
+human use, or, at best, is thinly inhabited by tribes too few in
+numbers, too poor in superfluous products, and too little advanced in
+culture and the social arts, to contribute anything to the general moral
+or material interests of the great commonwealth of man.
+
+
+_Causes of this Decay._
+
+The decay of these once flourishing countries is partly due, no doubt,
+to that class of geological causes, whose action we can neither resist
+nor guide, and partly also to the direct violence of hostile human
+force; but it is, in a far greater proportion, either the result of
+man's ignorant disregard of the laws of nature, or an incidental
+consequence of war, and of civil and ecclesiastical tyranny and misrule.
+Next to ignorance of these laws, the primitive source, the _causa
+causarum_, of the acts and neglects which have blasted with sterility
+and physical decrepitude the noblest half of the empire of the Caesars,
+is, first, the brutal and exhausting despotism which Rome herself
+exercised over her conquered kingdoms, and even over her Italian
+territory; then, the host of temporal and spiritual tyrannies which she
+left as her dying curse to all her wide dominion, and which, in some
+form of violence or of fraud, still brood over almost every soil subdued
+by the Roman legions.[1] Man cannot struggle at once against crushing
+oppression and the destructive forces of inorganic nature. When both are
+combined against him, he succumbs after a shorter or a longer struggle,
+and the fields he has won from the primeval wood relapse into their
+original state of wild and luxuriant, but unprofitable forest growth,
+or fall into that of a dry and barren wilderness.
+
+Rome imposed on the products of agricultural labor in the rural
+districts taxes which the sale of the entire harvest would scarcely
+discharge; she drained them of their population by military
+conscription; she impoverished the peasantry by forced and unpaid labor
+on public works; she hampered industry and internal commerce by absurd
+restrictions and unwise regulations. Hence, large tracts of land were
+left uncultivated, or altogether deserted, and exposed to all the
+destructive forces which act with such energy on the surface of the
+earth when it is deprived of those protections by which nature
+originally guarded it, and for which, in well-ordered husbandry, human
+ingenuity has contrived more or less efficient substitutes.[2] Similar
+abuses have tended to perpetuate and extend these evils in later ages,
+and it is but recently that, even in the most populous parts of Europe,
+public attention has been half awakened to the necessity of restoring
+the disturbed harmonies of nature, whose well-balanced influences are so
+propitious to all her organic offspring, of repaying to our great mother
+the debt which the prodigality and the thriftlessness of former
+generations have imposed upon their successors--thus fulfilling the
+command of religion and of practical wisdom, to use this world as not
+abusing it.
+
+
+_New School of Geographers._
+
+The labors of Humboldt, of Ritter, of Guyot and their followers, have
+given to the science of geography a more philosophical, and, at the same
+time, a more imaginative character than it had received from the hands
+of their predecessors. Perhaps the most interesting field of
+speculation, thrown open by the new school to the cultivators of this
+attractive study, is the inquiry: how far external physical conditions,
+and especially the configuration of the earth's surface, and the
+distribution, outline, and relative position of land and water, have
+influenced the social life and social progress of man.
+
+
+_Reaction of Man on Nature._
+
+But, as we have seen, man has reacted upon organized and inorganic
+nature, and thereby modified, if not determined, the material structure
+of his earthly home. The measure of that reaction manifestly constitutes
+a very important element in the appreciation of the relations between
+mind and matter, as well as in the discussion of many purely physical
+problems. But though the subject has been incidentally touched upon by
+many geographers, and treated with much fulness of detail in regard to
+certain limited fields of human effort, and to certain specific effects
+of human action, it has not, as a whole, so far as I know, been made
+matter of special observation, or of historical research by any
+scientific inquirer.[3] Indeed, until the influence of physical
+geography upon human life was recognized as a distinct branch of
+philosophical investigation, there was no motive for the pursuit of such
+speculations; and it was desirable to inquire whether we have or can
+become the architects of our own abiding place, only when it was known
+how the mode of our physical, moral, and intellectual being is affected
+by the character of the home which Providence has appointed, and we have
+fashioned, for our material habitation.[4]
+
+It is still too early to attempt scientific method in discussing this
+problem, nor is our present store of the necessary facts by any means
+complete enough to warrant me in promising any approach to fulness of
+statement respecting them. Systematic observation in relation to this
+subject has hardly yet begun,[5] and the scattered data which have
+chanced to be recorded have never been collected. It has now no place in
+the general scheme of physical science, and is matter of suggestion and
+speculation only, not of established and positive conclusion. At
+present, then, all that I can hope is to excite an interest in a topic
+of much economical importance, by pointing out the directions and
+illustrating the modes in which human action has been or may be most
+injurious or most beneficial in its influence upon the physical
+conditions of the earth we inhabit.
+
+
+_Observation of Nature._
+
+In these pages, as in all I have ever written or propose to write, it is
+my aim to stimulate, not to satisfy, curiosity, and it is no part of my
+object to save my readers the labor of observation or of thought. For
+labor is life, and
+
+ Death lives where power lives unused.[6]
+
+Self is the schoolmaster whose lessons are best worth his wages; and
+since the subject I am considering has not yet become a branch of formal
+instruction, those whom it may interest can, fortunately, have no
+pedagogue but themselves. To the natural philosopher, the descriptive
+poet, the painter, and the sculptor, as well as to the common observer,
+the power most important to cultivate, and, at the same time, hardest to
+acquire, is that of seeing what is before him. Sight is a faculty;
+seeing, an art. The eye is a physical, but not a self-acting apparatus,
+and in general it sees only what it seeks. Like a mirror, it reflects
+objects presented to it; but it may be as insensible as a mirror, and it
+does not necessarily perceive what it reflects.[7] It is disputed
+whether the purely material sensibility of the eye is capable of
+improvement and cultivation. It has been maintained by high authority,
+that the natural acuteness of none of our sensuous faculties can be
+heightened by use, and hence that the minutest details of the image
+formed on the retina are as perfect in the most untrained, as in the
+most thoroughly disciplined organ. This may well be doubted, and it is
+agreed on all hands that the power of multifarious perception and rapid
+discrimination may be immensely increased by well-directed practice.[8]
+This exercise of the eye I desire to promote, and, next to moral and
+religious doctrine, I know no more important practical lessons in this
+earthly life of ours--which, to the wise man, is a school from the
+cradle to the grave--than those relating to the employment of the sense
+of vision in the study of nature.
+
+The pursuit of physical geography, embracing actual observation of
+terrestrial surface, affords to the eye the best general training that
+is accessible to all. The majority of even cultivated men have not the
+time and means of acquiring anything beyond a very superficial
+acquaintance with any branch of physical knowledge. Natural science has
+become so vastly extended, its recorded facts and its unanswered
+questions so immensely multiplied, that every strictly scientific man
+must be a specialist, and confine the researches of a whole life within
+a comparatively narrow circle. The study I am recommending, in the view
+I propose to take of it, is yet in that imperfectly developed state
+which allows its votaries to occupy themselves with such broad and
+general views as are attainable by every person of culture, and it does
+not now require a knowledge of special details which only years of
+application can master. It may be profitably pursued by all; and every
+traveller, every lover of rural scenery, every agriculturist, who will
+wisely use the gift of sight, may add valuable contributions to the
+common stock of knowledge on a subject which, as I hope to convince my
+readers, though long neglected, and now inartificially presented, is not
+only a very important, but a very interesting field of inquiry.
+
+
+_Cosmical and Geological Influences._
+
+The revolutions of the seasons, with their alternations of temperature
+and of length of day and night, the climates of different zones, and the
+general condition and movements of the atmosphere and the seas, depend
+upon causes for the most part cosmical, and, of course, wholly beyond
+our control. The elevation, configuration, and composition of the great
+masses of terrestrial surface, and the relative extent and distribution
+of land and water, are determined by geological influences equally
+remote from our jurisdiction. It would hence seem that the physical
+adaptation of different portions of the earth to the use and enjoyment
+of man is a matter so strictly belonging to mightier than human powers,
+that we can only accept geographical nature as we find her, and be
+content with such soils and such skies as she spontaneously offers.
+
+
+_Geographical Influence of Man._
+
+But it is certain that man has done much to mould the form of the
+earth's surface, though we cannot always distinguish between the results
+of his action and the effects of purely geological causes; that the
+destruction of the forests, the drainage of lakes and marshes, and the
+operations of rural husbandry and industrial art have tended to produce
+great changes in the hygrometric, thermometric, electric, and chemical
+condition of the atmosphere, though we are not yet able to measure the
+force of the different elements of disturbance, or to say how far they
+have been compensated by each other, or by still obscurer influences;
+and, finally, that the myriad forms of animal and vegetable life, which
+covered the earth when man first entered upon the theatre of a nature
+whose harmonies he was destined to derange, have been, through his
+action, greatly changed in numerical proportion, sometimes much modified
+in form and product, and sometimes entirely extirpated.
+
+The physical revolutions thus wrought by man have not all been
+destructive to human interests. Soils to which no nutritious vegetable
+was indigenous, countries which once brought forth but the fewest
+products suited for the sustenance and comfort of man--while the
+severity of their climates created and stimulated the greatest number
+and the most imperious urgency of physical wants--surfaces the most
+rugged and intractable, and least blessed with natural facilities of
+communication, have been made in modern times to yield and distribute
+all that supplies the material necessities, all that contributes to the
+sensuous enjoyments and conveniences of civilized life. The Scythia, the
+Thule, the Britain, the Germany, and the Gaul which the Roman writers
+describe in such forbidding terms, have been brought almost to rival the
+native luxuriance and easily won plenty of Southern Italy; and, while
+the fountains of oil and wine that refreshed old Greece and Syria and
+Northern Africa have almost ceased to flow, and the soils of those fair
+lands are turned to thirsty and inhospitable deserts, the hyperborean
+regions of Europe have conquered, or rather compensated, the rigors of
+climate, and attained to a material wealth and variety of product that,
+with all their natural advantages, the granaries of the ancient world
+can hardly be said to have enjoyed.
+
+These changes for evil and for good have not been caused by great
+natural revolutions of the globe, nor are they by any means attributable
+wholly to the moral and physical action or inaction of the peoples, or,
+in all cases, even of the races that now inhabit these respective
+regions. They are products of a complication of conflicting or
+coincident forces, acting through a long series of generations; here,
+improvidence, wastefulness, and wanton violence; there, foresight and
+wisely guided persevering industry. So far as they are purely the
+calculated and desired results of those simple and familiar operations
+of agriculture and of social life which are as universal as
+civilization--the removal of the forests which covered the soil required
+for the cultivation of edible fruits, the drying of here and there a few
+acres too moist for profitable husbandry, by draining off the surface
+waters, the substitution of domesticated and nutritious for wild and
+unprofitable vegetable growths, the construction of roads and canals and
+artificial harbors--they belong to the sphere of rural, commercial, and
+political economy more properly than to geography, and hence are but
+incidentally embraced within the range of our present inquiries, which
+concern physical, not financial balances. I propose to examine only the
+greater, more permanent, and more comprehensive mutations which man has
+produced, and is producing, in earth, sea, and sky, sometimes, indeed,
+with conscious purpose, but for the most part, as unforeseen though
+natural consequences of acts performed for narrower and more immediate
+ends.
+
+The exact measurement of the geographical changes hitherto thus effected
+is, as I have hinted, impracticable, and we possess, in relation to
+them, the means of only qualitative, not quantitative analysis. The fact
+of such revolutions is established partly by historical evidence, partly
+by analogical deduction from effects produced in our own time by
+operations similar in character to those which must have taken place in
+more or less remote ages of human action. Both sources of information
+are alike defective in precision; the latter, for general reasons too
+obvious to require specification; the former, because the facts to which
+it bears testimony occurred before the habit or the means of rigorously
+scientific observation upon any branch of physical research, and
+especially upon climatic changes, existed.
+
+
+_Uncertainty of our Meteorological Knowledge._
+
+The invention of measures of heat, and of atmospheric moisture,
+pressure, and precipitation, is extremely recent. Hence, ancient
+physicists have left us no thermometric or barometric records, no tables
+of the fall, evaporation, and flow of waters, and even no accurate maps
+of coast lines and the course of rivers. Their notices of these
+phenomena are almost wholly confined to excessive and exceptional
+instances of high or of low temperatures, extraordinary falls of rain
+and snow, and unusual floods or droughts. Our knowledge of the
+meteorological condition of the earth, at any period more than two
+centuries before our own time, is derived from these imperfect details,
+from the vague statements of ancient historians and geographers in
+regard to the volume of rivers and the relative extent of forest and
+cultivated land, from the indications furnished by the history of the
+agriculture and rural economy of past generations, and from other almost
+purely casual sources of information.
+
+Among these latter we must rank certain newly laid open fields of
+investigation, from which facts bearing on the point now under
+consideration have been gathered. I allude to the discovery of
+artificial objects in geological formations older than any hitherto
+recognized as exhibiting traces of the existence of man; to the ancient
+lacustrine habitations of Switzerland, containing the implements of the
+occupants, remains of their food, and other relics of human life; to the
+curious revelations of the Kjoekkenmoeddinger, or heaps of kitchen refuse,
+in Denmark, and of the peat mosses in the same and other northern
+countries; to the dwellings and other evidences of the industry of man
+in remote ages sometimes laid bare by the movement of sand dunes on the
+coasts of France and of the North Sea; and to the facts disclosed on the
+shores of the latter, by excavations in inhabited mounds which were,
+perhaps, raised before the period of the Roman Empire. These remains are
+memorials of races which have left no written records, because they
+perished before the historical period of the countries they occupied
+began. The plants and animals that furnished the relics found in the
+deposits were certainly contemporaneous with man; for they are
+associated with his works, and have evidently served his uses. In some
+cases, the animals belonged to species well ascertained to be now
+altogether extinct; in some others, both the animals and the vegetables,
+though extant elsewhere, have ceased to inhabit the regions where their
+remains are discovered. From the character of the artificial objects, as
+compared with others belonging to known dates, or at least to known
+periods of civilization, ingenious inferences have been drawn as to
+their age; and from the vegetation, remains of which accompany them, as
+to the climates of Central and Northern Europe at the time of their
+production.
+
+There are, however, sources of error which have not always been
+sufficiently guarded against in making these estimates. When a boat,
+composed of several pieces of wood fastened together by pins of the same
+material, is dug out of a bog, it is inferred that the vessel, and the
+skeletons and implements found with it, belong to an age when the use of
+iron was not known to the builders. But this conclusion is not warranted
+by the simple fact that metals were not employed in its construction;
+for the Nubians at this day build boats large enough to carry half a
+dozen persons across the Nile, out of small pieces of acacia wood pinned
+together entirely with wooden bolts. Nor is the occurrence of flint
+arrow heads and knives, in conjunction with other evidences of human
+life, conclusive proof as to the antiquity of the latter. Lyell informs
+us that some Oriental tribes still continue to use the same stone
+implements as their ancestors, "after that mighty empires, where the use
+of metals in the arts was well known, had flourished for three thousand
+years in their neighborhood;"[9] and the North American Indians now
+manufacture and use weapons of stone, and even of glass, chipping them
+in the latter case out of the bottoms of thick bottles, with great
+facility.[10]
+
+We may also be misled by our ignorance of the commercial relations
+existing between savage tribes. Extremely rude nations, in spite of
+their jealousies and their perpetual wars, sometimes contrive to
+exchange the products of provinces very widely separated from each
+other. The mounds of Ohio contain pearls, thought to be marine, which
+must have come from the Gulf of Mexico, or perhaps even from California,
+and the knives and pipes found in the same graves are often formed of
+far-fetched material, that was naturally paid for by some home product
+exported to the locality whence the material was derived. The art of
+preserving fish, flesh, and fowl by drying and smoking is widely
+diffused, and of great antiquity. The Indians of Long Island Sound are
+said to have carried on a trade in dried shell fish with tribes residing
+very far inland. From the earliest ages, the inhabitants of the Faroe
+and Orkney Islands, and of the opposite mainland coasts, have smoked
+wild fowl and other flesh. Hence it is possible that the animal and the
+vegetable food, the remains of which are found in the ancient deposits I
+am speaking of, may sometimes have been brought from climates remote
+from that where it was consumed.
+
+The most important, as well as the most trustworthy conclusions with
+respect to the climate of ancient Europe and Asia, are those drawn from
+the accounts given by the classical writers of the growth of cultivated
+plants; but these are by no means free from uncertainty, because we can
+seldom be sure of an identity of species, almost never of an identity of
+race or variety, between vegetables known to the agriculturists of
+Greece and Rome and those of modern times which are thought most nearly
+to resemble them. Besides this, there is always room for doubt whether
+the habits of plants long grown in different countries may not have been
+so changed by domestication that the conditions of temperature and
+humidity which they required twenty centuries ago were different from
+those at present demanded for their advantageous cultivation.[11]
+
+Even if we suppose an identity of species, of race, and of habit to be
+established between a given ancient and modern plant, the negative fact
+that the latter will not grow now where it flourished two thousand years
+ago does not in all cases prove a change of climate. The same result
+might follow from the exhaustion of the soil,[12] or from a change in
+the quantity of moisture it habitually contains. After a district of
+country has been completely or even partially cleared of its forest
+growth, and brought under cultivation, the drying of the soil, under
+favorable circumstances, goes on for generations, perhaps for ages.[13]
+In other cases, from injudicious husbandry, or the diversion or choking
+up of natural watercourses, it may become more highly charged with
+humidity. An increase or diminution of the moisture of a soil almost
+necessarily supposes an elevation or a depression of its winter or its
+summer heat, and of its extreme, if not of its mean annual temperature,
+though such elevation or depression may be so slight as not sensibly to
+raise or lower the mercury in a thermometer exposed to the open air. Any
+of these causes, more or less humidity, or more or less warmth of soil,
+would affect the growth both of wild and of cultivated vegetation, and
+consequently, without any appreciable change in atmospheric temperature,
+precipitation, or evaporation, plants of a particular species might
+cease to be advantageously cultivated where they had once been easily
+reared.[14] We are very imperfectly acquainted with the present mean
+and extreme temperature, or the precipitation and the evaporation of any
+extensive region, even in countries most densely peopled and best
+supplied with instruments and observers. The progress of science is
+constantly detecting errors of method in older observations, and many
+laboriously constructed tables of meteorological phenomena are now
+thrown aside as fallacious, and therefore worse than useless, because
+some condition necessary to secure accuracy of result was neglected, in
+obtaining the data on which they were founded.
+
+To take a familiar instance: it is but recently that attention has been
+drawn to the great influence of slight changes of station upon the
+results of observations of temperature and precipitation. A thermometer
+removed but a few hundred yards from its first position differs not
+unfrequently five, sometimes even ten degrees in its readings; and when
+we are told that the annual fall of rain on the roof of the observatory
+at Paris is two inches less than on the ground by the side of it, we may
+see that the level of the rain-gauge is a point of much consequence in
+making estimates from its measurements. The data from which results have
+been deduced with respect to the hygrometrical and thermometrical
+conditions, the climate in short, of different countries, have very
+often been derived from observations at single points in cities or
+districts separated by considerable distances. The tendency of errors
+and accidents to balance each other authorizes us, indeed, to entertain
+greater confidence than we could otherwise feel in the conclusions drawn
+from such tables; but it is in the highest degree probable that they
+would be much modified by more numerous series of observations, at
+different stations within narrow limits.[15]
+
+There is one branch of research which is of the utmost importance in
+reference to these questions, but which, from the great difficulty of
+direct observation upon it, has been less successfully studied than
+almost any other problem of physical science. I refer to the proportions
+between precipitation, superficial drainage, absorption, and
+evaporation. Precise actual measurement of these quantities upon even a
+single acre of ground is impossible; and in all cabinet experiments on
+the subject, the conditions of the surface observed are so different
+from those which occur in nature, that we cannot safely reason from one
+case to the other. In nature, the inclination of the ground, the degree
+of freedom or obstruction of the surface, the composition and density of
+the soil, upon which its permeability by water and its power of
+absorbing and retaining or transmitting moisture depend, its
+temperature, the dryness or saturation of the subsoil, vary at
+comparatively short distances; and though the precipitation upon and the
+superficial flow from very small geographical basins may be estimated
+with an approach to precision, yet even here we have no present means
+of knowing how much of the water absorbed by the earth is restored to
+the atmosphere by evaporation, and how much carried off by infiltration
+or other modes of underground discharge. When, therefore, we attempt to
+use the phenomena observed on a few square or cubic yards of earth, as a
+basis of reasoning upon the meteorology of a province, it is evident
+that our data must be insufficient to warrant positive general
+conclusions. In discussing the climatology of whole countries, or even
+of comparatively small local divisions, we may safely say that none can
+tell what percentage of the water they receive from the atmosphere is
+evaporated; what absorbed by the ground and conveyed off by subterranean
+conduits; what carried down to the sea by superficial channels; what
+drawn from the earth or the air by a given extent of forest, of short
+pasture vegetation, or of tall meadow-grass; what given out again by
+surfaces so covered, or by bare ground of various textures and
+composition, under different conditions of atmospheric temperature,
+pressure, and humidity; or what is the amount of evaporation from water,
+ice, or snow, under the varying exposures to which, in actual nature,
+they are constantly subjected. If, then, we are so ignorant of all these
+climatic phenomena in the best-known regions inhabited by man, it is
+evident that we can rely little upon theoretical deductions applied to
+the former more natural state of the same regions--less still to such as
+are adopted with respect to distant, strange, and primitive countries.
+
+
+_Mechanical Effects produced by Man on the Surface of the Earth more
+easily ascertainable._
+
+In investigating the mechanical effects of human action on superficial
+geography, we are treading on safer ground, and dealing with much less
+subtile phenomena, less intractable elements. Great physical changes
+can, in some cases, be positively shown, in some almost certainly
+inferred, to have been produced by the operations of rural industry, and
+by the labors of man in other spheres of material effort; and hence, in
+this most important part of our subject, we can arrive at many positive
+generalizations, and obtain practical results of no small economical
+value.
+
+
+_Importance and Possibility of Physical Restoration._
+
+Many circumstances conspire to invest with great present interest the
+questions: how far man can permanently modify and ameliorate those
+physical conditions of terrestrial surface and climate on which his
+material welfare depends; how far he can compensate, arrest, or retard
+the deterioration which many of his agricultural and industrial
+processes tend to produce; and how far he can restore fertility and
+salubrity to soils which his follies or his crimes have made barren or
+pestilential. Among these circumstances, the most prominent, perhaps, is
+the necessity of providing new homes for a European population which is
+increasing more rapidly than its means of subsistence, new physical
+comforts for classes of the people that have now become too much
+enlightened and have imbibed too much culture to submit to a longer
+deprivation of a share in the material enjoyments which the privileged
+ranks have hitherto monopolized.
+
+To supply new hives for the emigrant swarms, there are, first, the vast
+unoccupied prairies and forests of America, of Australia, and of many
+other great oceanic islands, the sparsely inhabited and still
+unexhausted soils of Southern and even Central Africa, and, finally, the
+impoverished and half-depopulated shores of the Mediterranean, and the
+interior of Asia Minor and the farther East. To furnish to those who
+shall remain after emigration shall have conveniently reduced the too
+dense population of many European states, those means of sensuous and of
+intellectual well-being which are styled "artificial wants" when
+demanded by the humble and the poor, but are admitted to be
+"necessaries" when claimed by the noble and the rich, the soil must be
+stimulated to its highest powers of production, and man's utmost
+ingenuity and energy must be tasked to renovate a nature drained, by
+his improvidence, of fountains which a wise economy would have made
+plenteous and perennial sources of beauty, health, and wealth.
+
+In those yet virgin lands which the progress of modern discovery in both
+hemispheres has brought and is still bringing to the knowledge and
+control of civilized man, not much improvement of great physical
+conditions is to be looked for. The proportion of forest is indeed to be
+considerably reduced, superfluous waters to be drawn off, and routes of
+internal communication to be constructed; but the primitive geographical
+and climatic features of these countries ought to be, as far as
+possible, retained.
+
+
+_Stability of Nature._
+
+Nature, left undisturbed, so fashions her territory as to give it almost
+unchanging permanence of form, outline, and proportion, except when
+shattered by geologic convulsions; and in these comparatively rare cases
+of derangement, she sets herself at once to repair the superficial
+damage, and to restore, as nearly as practicable, the former aspect of
+her dominion. In new countries, the natural inclination of the ground,
+the self-formed slopes and levels, are generally such as best secure the
+stability of the soil. They have been graded and lowered or elevated by
+frost and chemical forces and gravitation and the flow of water and
+vegetable deposit and the action of the winds, until, by a general
+compensation of conflicting forces, a condition of equilibrium has been
+reached which, without the action of man, would remain, with little
+fluctuation, for countless ages.
+
+We need not go far back to reach a period when, in all that portion of
+the North American continent which has been occupied by British
+colonization, the geographical elements very nearly balanced and
+compensated each other. At the commencement of the seventeenth century,
+the soil, with insignificant exceptions, was covered with forests;[16]
+and whenever the Indian, in consequence of war or the exhaustion of the
+beasts of the chase, abandoned the narrow fields he had planted and the
+woods he had burned over, they speedily returned, by a succession of
+herbaceous, arborescent, and arboreal growths, to their original state.
+Even a single generation sufficed to restore them almost to their
+primitive luxuriance of forest vegetation.[17] The unbroken forests had
+attained to their maximum density and strength of growth, and, as the
+older trees decayed and fell, they were succeeded by new shoots or
+seedlings, so that from century to century no perceptible change seems
+to have occurred in the wood, except the slow, spontaneous succession of
+crops. This succession involved no interruption of growth, and but
+little break in the "boundless contiguity of shade;" for, in the
+husbandry of nature, there are no fallows. Trees fall singly, not by
+square roods, and the tall pine is hardly prostrate, before the light
+and heat, admitted to the ground by the removal of the dense crown of
+foliage which had shut them out, stimulate the germination of the seeds
+of broad-leaved trees that had lain, waiting this kindly influence,
+perhaps for centuries. Two natural causes, destructive in character,
+were, indeed, in operation in the primitive American forests, though, in
+the Northern colonies, at least, there were sufficient compensations;
+for we do not discover that any considerable permanent change was
+produced by them. I refer to the action of beavers and of fallen trees
+in producing bogs,[18] and of smaller animals, insects, and birds, in
+destroying the woods. Bogs are less numerous and extensive in the
+Northern States of the American union, because the natural inclination
+of the surface favors drainage; but they are more frequent, and cover
+more ground, in the Southern States, for the opposite reason.[19] They
+generally originate in the checking of watercourses by the falling of
+timber, or of earth and rocks, across their channels. If the impediment
+thus created is sufficient to retain a permanent accumulation of water
+behind it, the trees whose roots are overflowed soon perish, and then by
+their fall increase the obstruction, and, of course, occasion a still
+wider spread of the stagnating stream. This process goes on until the
+water finds a new outlet, at a higher level, not liable to similar
+interruption. The fallen trees not completely covered by water are soon
+overgrown with mosses; aquatic and semi-aquatic plants propagate
+themselves, and spread until they more or less completely fill up the
+space occupied by the water, and the surface is gradually converted from
+a pond to a quaking morass.[20] The morass is slowly solidified by
+vegetable production and deposit, then very often restored to the
+forest condition by the growth of black ashes, cedars, or, in southern
+latitudes, cypresses, and other trees suited to such a soil, and thus
+the interrupted harmony of nature is at last reestablished.
+
+I am disposed to think that more bogs in the Northern States owe their
+origin to beavers than to accidental obstructions of rivulets by
+wind-fallen or naturally decayed trees; for there are few swamps in
+those States, at the outlets of which we may not, by careful search,
+find the remains of a beaver dam. The beaver sometimes inhabits natural
+lakelets, but he prefers to owe his pond to his own ingenuity and toil.
+The reservoir once constructed, its inhabitants rapidly multiply, and as
+its harvests of pond lilies, and other aquatic plants on which this
+quadruped feeds in winter, become too small for the growing population,
+the beaver metropolis sends out expeditions of discovery and
+colonization. The pond gradually fills up, by the operation of the same
+causes as when it owes its existence to an accidental obstruction, and
+when, at last, the original settlement is converted into a bog by the
+usual processes of vegetable life, the remaining inhabitants abandon it
+and build on some virgin brooklet a new city of the waters.
+
+In countries somewhat further advanced in civilization than those
+occupied by the North American Indians, as in mediaeval Ireland, the
+formation of bogs may be commenced by the neglect of man to remove, from
+the natural channels of superficial drainage, the tops and branches of
+trees felled for the various purposes to which wood is applicable in
+his rude industry; and, when the flow of the water is thus checked,
+nature goes on with the processes I have already described. In such
+half-civilized regions, too, windfalls are more frequent than in those
+where the forest is unbroken, because, when openings have been made in
+it, for agricultural or other purposes, the entrance thus afforded to
+the wind occasions the sudden overthrow of hundreds of trees which might
+otherwise have stood for generations, and thus have fallen to the
+ground, only one by one, as natural decay brought them down.[21] Besides
+this, the flocks bred by man in the pastoral state, keep down the
+incipient growth of trees on the half-dried bogs, and prevent them from
+recovering their primitive condition.
+
+Young trees in the native forest are sometimes girdled and killed by the
+smaller rodent quadrupeds, and their growth is checked by birds which
+feed on the terminal bud; but these animals, as we shall see, are
+generally found on the skirts of the wood only, not in its deeper
+recesses, and hence the mischief they do is not extensive. The insects
+which damage primitive forests by feeding upon products of trees
+essential to their growth, are not numerous, nor is their appearance, in
+destructive numbers, frequent; and those which perforate the stems and
+branches, to deposit and hatch their eggs, more commonly select dead
+trees for that purpose, though, unhappily, there are important
+exceptions to this latter remark.[22] I do not know that we have any
+evidence of the destruction or serious injury of American forests by
+insects, before or even soon after the period of colonization; but since
+the white man has laid bare a vast proportion of the earth's surface,
+and thereby produced changes favorable, perhaps, to the multiplication
+of these pests, they have greatly increased in numbers, and, apparently,
+in voracity also. Not many years ago, the pines on thousands of acres of
+land in North Carolina, were destroyed by insects not known to have ever
+done serious injury to that tree before. In such cases as this and
+others of the like sort, there is good reason to believe that man is the
+indirect cause of an evil for which he pays so heavy a penalty. Insects
+increase whenever the birds which feed upon them disappear. Hence, in
+the wanton destruction of the robin and other insectivorous birds, the
+_bipes implumis_, the featherless biped, man, is not only exchanging the
+vocal orchestra which greets the rising sun for the drowsy beetle's
+evening drone, and depriving his groves and his fields of their fairest
+ornament, but he is waging a treacherous warfare on his natural
+allies.[23]
+
+In fine, in countries untrodden by man, the proportions and relative
+positions of land and water, the atmospheric precipitation and
+evaporation, the thermometric mean, and the distribution of vegetable
+and animal life, are subject to change only from geological influences
+so slow in their operation that the geographical conditions may be
+regarded as constant and immutable. These arrangements of nature it is,
+in most cases, highly desirable substantially to maintain, when such
+regions become the seat of organized commonwealths. It is, therefore, a
+matter of the first importance, that, in commencing the process of
+fitting them for permanent civilized occupation, the transforming
+operations should be so conducted as not unnecessarily to derange and
+destroy what, in too many cases, it is beyond the power of man to
+rectify or restore.
+
+
+_Restoration of Disturbed Harmonies._
+
+In reclaiming and reoccupying lands laid waste by human improvidence or
+malice, and abandoned by man, or occupied only by a nomade or thinly
+scattered population, the task of the pioneer settler is of a very
+different character. He is to become a co-worker with nature in the
+reconstruction of the damaged fabric which the negligence or the
+wantonness of former lodgers has rendered untenantable. He must aid her
+in reclothing the mountain slopes with forests and vegetable mould,
+thereby restoring the fountains which she provided to water them; in
+checking the devastating fury of torrents, and bringing back the surface
+drainage to its primitive narrow channels; and in drying deadly morasses
+by opening the natural sluices which have been choked up, and cutting
+new canals for drawing off their stagnant waters. He must thus, on the
+one hand, create new reservoirs, and, on the other, remove mischievous
+accumulations of moisture, thereby equalizing and regulating the sources
+of atmospheric humidity and of flowing water, both which are so
+essential to all vegetable growth, and, of course, to human and lower
+animal life.
+
+
+_Destructiveness of Man._
+
+Man has too long forgotten that the earth was given to him for usufruct
+alone, not for consumption, still less for profligate waste. Nature has
+provided against the absolute destruction of any of her elementary
+matter, the raw material of her works; the thunderbolt and the tornado,
+the most convulsive throes of even the volcano and the earthquake, being
+only phenomena of decomposition and recomposition. But she has left it
+within the power of man irreparably to derange the combinations of
+inorganic matter and of organic life, which through the night of aeons
+she had been proportioning and balancing, to prepare the earth for his
+habitation, when, in the fulness of time, his Creator should call him
+forth to enter into its possession.
+
+Apart from the hostile influence of man, the organic and the inorganic
+world are, as I have remarked, bound together by such mutual relations
+and adaptations as secure, if not the absolute permanence and
+equilibrium of both, a long continuance of the established conditions of
+each at any given time and place, or at least, a very slow and gradual
+succession of changes in those conditions. But man is everywhere a
+disturbing agent. Wherever he plants his foot, the harmonies of nature
+are turned to discords. The proportions and accommodations which insured
+the stability of existing arrangements are overthrown. Indigenous
+vegetable and animal species are extirpated, and supplanted by others of
+foreign origin, spontaneous production is forbidden or restricted, and
+the face of the earth is either laid bare or covered with a new and
+reluctant growth of vegetable forms, and with alien tribes of animal
+life. These intentional changes and substitutions constitute, indeed,
+great revolutions; but vast as is their magnitude and importance, they
+are, as we shall see, insignificant in comparison with the contingent
+and unsought results which have flowed from them.
+
+The fact that, of all organic beings, man alone is to be regarded as
+essentially a destructive power, and that he wields energies to resist
+which, nature--that Nature whom all material life and all inorganic
+substance obey--is wholly impotent, tends to prove that, though living
+in physical nature, he is not of her, that he is of more exalted
+parentage, and belongs to a higher order of existences than those born
+of her womb and submissive to her dictates.
+
+There are, indeed, brute destroyers, beasts and birds and insects of
+prey--all animal life feeds upon, and, of course, destroys other
+life,--but this destruction is balanced by compensations. It is, in
+fact, the very means by which the existence of one tribe of animals or
+of vegetables is secured against being smothered by the encroachments of
+another; and the reproductive powers of species, which serve as the food
+of others, are always proportioned to the demand they are destined to
+supply. Man pursues his victims with reckless destructiveness; and,
+while the sacrifice of life by the lower animals is limited by the
+cravings of appetite, he unsparingly persecutes, even to extirpation,
+thousands of organic forms which he cannot consume.[24]
+
+The earth was not, in its natural condition, completely adapted to the
+use of man, but only to the sustenance of wild animals and wild
+vegetation. These live, multiply their kind in just proportion, and
+attain their perfect measure of strength and beauty, without producing
+or requiring any change in the natural arrangements of surface, or in
+each other's spontaneous tendencies, except such mutual repression of
+excessive increase as may prevent the extirpation of one species by the
+encroachments of another. In short, without man, lower animal and
+spontaneous vegetable life would have been constant in type,
+distribution, and proportion, and the physical geography of the earth
+would have remained undisturbed for indefinite periods, and been subject
+to revolution only from possible, unknown cosmical causes, or from
+geological action.
+
+But man, the domestic animals that serve him, the field and garden
+plants the products of which supply him with food and clothing, cannot
+subsist and rise to the full development of their higher properties,
+unless brute and unconscious nature be effectually combated, and, in a
+great degree, vanquished by human art. Hence, a certain measure of
+transformation of terrestrial surface, of suppression of natural, and
+stimulation of artificially modified productivity becomes necessary.
+This measure man has unfortunately exceeded. He has felled the forests
+whose network of fibrous roots bound the mould to the rocky skeleton of
+the earth; but had he allowed here and there a belt of woodland to
+reproduce itself by spontaneous propagation, most of the mischiefs which
+his reckless destruction of the natural protection of the soil has
+occasioned would have been averted. He has broken up the mountain
+reservoirs, the percolation of whose waters through unseen channels
+supplied the fountains that refreshed his cattle and fertilized his
+fields; but he has neglected to maintain the cisterns and the canals of
+irrigation which a wise antiquity had constructed to neutralize the
+consequences of its own imprudence. While he has torn the thin glebe
+which confined the light earth of extensive plains, and has destroyed
+the fringe of semi-aquatic plants which skirted the coast and checked
+the drifting of the sea sand, he has failed to prevent the spreading of
+the dunes by clothing them with artificially propagated vegetation. He
+has ruthlessly warred on all the tribes of animated nature whose spoil
+he could convert to his own uses, and he has not protected the birds
+which prey on the insects most destructive to his own harvests.
+
+Purely untutored humanity, it is true, interferes comparatively little
+with the arrangements of nature,[25] and the destructive agency of man
+becomes more and more energetic and unsparing as he advances in
+civilization, until the impoverishment, with which his exhaustion of the
+natural resources of the soil is threatening him, at last awakens him to
+the necessity of preserving what is left, if not of restoring what has
+been wantonly wasted. The wandering savage grows no cultivated
+vegetable, fells no forest, and extirpates no useful plant, no noxious
+weed. If his skill in the chase enables him to entrap numbers of the
+animals on which he feeds, he compensates this loss by destroying also
+the lion, the tiger, the wolf, the otter, the seal, and the eagle, thus
+indirectly protecting the feebler quadrupeds and fish and fowls, which
+would otherwise become the booty of beasts and birds of prey. But with
+stationary life, or rather with the pastoral state, man at once
+commences an almost indiscriminate warfare upon all the forms of animal
+and vegetable existence around him, and as he advances in civilization,
+he gradually eradicates or transforms every spontaneous product of the
+soil he occupies.[26]
+
+
+_Human and Brute Action Compared._
+
+It has been maintained by authorities as high as any known to modern
+science, that the action of man upon nature, though greater in _degree_,
+does not differ in _kind_, from that of wild animals. It appears to me
+to differ in essential character, because, though it is often followed
+by unforeseen and undesired results, yet it is nevertheless guided by a
+self-conscious and intelligent will aiming as often at secondary and
+remote as at immediate objects. The wild animal, on the other hand, acts
+instinctively, and, so far as we are able to perceive, always with a
+view to single and direct purposes. The backwoodsman and the beaver
+alike fell trees; the man that he may convert the forest into an olive
+grove that will mature its fruit only for a succeeding generation, the
+beaver that he may feed upon their bark or use them in the construction
+of his habitation. Human differs from brute action, too, in its
+influence upon the material world, because it is not controlled by
+natural compensations and balances. Natural arrangements, once disturbed
+by man, are not restored until he retires from the field, and leaves
+free scope to spontaneous recuperative energies; the wounds he inflicts
+upon the material creation are not healed until he withdraws the arm
+that gave the blow. On the other hand, I am not aware of any evidence
+that wild animals have ever destroyed the smallest forest, extirpated
+any organic species or modified its natural character, occasioned any
+permanent change of terrestrial surface, or produced any disturbance of
+physical conditions which nature has not, of herself, repaired without
+the expulsion of the animal that had caused it.[27]
+
+The form of geographical surface, and very probably the climate of a
+given country, depend much on the character of the vegetable life
+belonging to it. Man has, by domestication, greatly changed the habits
+and properties of the plants he rears; he has, by voluntary selection,
+immensely modified the forms and qualities of the animated creatures
+that serve him; and he has, at the same time, completely rooted out many
+forms of animal if not of vegetable being.[28] What is there, in the
+influence of brute life, that corresponds to this? We have no reason to
+believe that in that portion of the American continent which, though
+peopled by many tribes of quadruped and fowl, remained uninhabited by
+man, or only thinly occupied by purely savage tribes, any sensible
+geographical change had occurred within twenty centuries before the
+epoch of discovery and colonization, while, during the same period, man
+had changed millions of square miles, in the fairest and most fertile
+regions of the Old World, into the barrenest deserts.
+
+The ravages committed by man subvert the relations and destroy the
+balance which nature had established between her organized and her
+inorganic creations; and she avenges herself upon the intruder, by
+letting loose upon her defaced provinces destructive energies hitherto
+kept in check by organic forces destined to be his best auxiliaries, but
+which he has unwisely dispersed and driven from the field of action.
+When the forest is gone, the great reservoir of moisture stored up in
+its vegetable mould is evaporated, and returns only in deluges of rain
+to wash away the parched dust into which that mould has been converted.
+The well-wooded and humid hills are turned to ridges of dry rock, which
+encumbers the low grounds and chokes the watercourses with its debris,
+and--except in countries favored with an equable distribution of rain
+through the seasons, and a moderate and regular inclination of
+surface--the whole earth, unless rescued by human art from the physical
+degradation to which it tends, becomes an assemblage of bald mountains,
+of barren, turfless hills, and of swampy and malarious plains. There are
+parts of Asia Minor, of Northern Africa, of Greece, and even of Alpine
+Europe, where the operation of causes set in action by man has brought
+the face of the earth to a desolation almost as complete as that of the
+moon; and though, within that brief space of time which we call "the
+historical period," they are known to have been covered with luxuriant
+woods, verdant pastures, and fertile meadows, they are now too far
+deteriorated to be reclaimable by man, nor can they become again fitted
+for human use, except through great geological changes, or other
+mysterious influences or agencies of which we have no present knowledge,
+and over which we have no prospective control. The earth is fast
+becoming an unfit home for its noblest inhabitant, and another era of
+equal human crime and human improvidence, and of like duration with that
+through which traces of that crime and that improvidence extend, would
+reduce it to such a condition of impoverished productiveness, of
+shattered surface, of climatic excess, as to threaten the depravation,
+barbarism, and perhaps even extinction of the species.[29]
+
+
+_Physical Improvement._
+
+True, there is a partial reverse to this picture. On narrow theatres,
+new forests have been planted; inundations of flowing streams restrained
+by heavy walls of masonry and other constructions; torrents compelled to
+aid, by depositing the slime with which they are charged, in filling up
+lowlands, and raising the level of morasses which their own overflows
+had created; ground submerged by the encroachments of the ocean, or
+exposed to be covered by its tides, has been rescued from its dominion
+by diking;[30] swamps and even lakes have been drained, and their beds
+brought within the domain of agricultural industry; drifting coast dunes
+have been checked and made productive by plantation; seas and inland
+waters have been repeopled with fish, and even the sands of the Sahara
+have been fertilized by artesian fountains. These achievements are more
+glorious than the proudest triumphs of war, but, thus far, they give but
+faint hope that we shall yet make full atonement for our spendthrift
+waste of the bounties of nature.
+
+It is, on the one hand, rash and unphilosophical to attempt to set
+limits to the ultimate power of man over inorganic nature, and it is
+unprofitable, on the other, to speculate on what may be accomplished by
+the discovery of now unknown and unimagined natural forces, or even by
+the invention of new arts and new processes. But since we have seen
+aerostation, the motive power of elastic vapors, the wonders of modern
+telegraphy, the destructive explosiveness of gunpowder, and even of a
+substance so harmless, unresisting, and inert as cotton, nothing in the
+way of mechanical achievement seems impossible, and it is hard to
+restrain the imagination from wandering forward a couple of generations
+to an epoch when our descendants shall have advanced as far beyond us in
+physical conquest, as we have marched beyond the trophies erected by our
+grandfathers.
+
+I must therefore be understood to mean only, that no agencies now known
+to man and directed by him seem adequate to the reducing of great Alpine
+precipices to such slopes as would enable them to support a vegetable
+clothing, or to the covering of large extents of denuded rock with
+earth, and planting upon them a forest growth. But among the mysteries
+which science is yet to reveal, there may be still undiscovered methods
+of accomplishing even grander wonders than these. Mechanical
+philosophers have suggested the possibility of accumulating and
+treasuring up for human use some of the greater natural forces, which
+the action of the elements puts forth with such astonishing energy.
+Could we gather, and bind, and make subservient to our control, the
+power which a West Indian hurricane exerts through a small area in one
+continuous blast, or the momentum expended by the waves, in a
+tempestuous winter, upon the breakwater at Cherbourg,[31] or the lifting
+power of the tide, for a month, at the head of the Bay of Fundy, or the
+pressure of a square mile of sea water at the depth of five thousand
+fathoms, or a moment of the might of an earthquake or a volcano, our
+age--which moves no mountains and casts them into the sea by faith
+alone--might hope to scarp the rugged walls of the Alps and Pyrenees and
+Mount Taurus, robe them once more in a vegetation as rich as that of
+their pristine woods, and turn their wasting torrents into refreshing
+streams.[32]
+
+Could this old world, which man has overthrown, be rebuilded, could
+human cunning rescue its wasted hillsides and its deserted plains from
+solitude or mere nomade occupation, from barrenness, from nakedness, and
+from insalubrity, and restore the ancient fertility and healthfulness of
+the Etruscan sea coast, the Campagna and the Pontine marshes, of
+Calabria, of Sicily, of the Peloponnesus and insular and continental
+Greece, of Asia Minor, of the slopes of Lebanon and Hermon, of
+Palestine, of the Syrian desert, of Mesopotamia and the delta of the
+Euphrates, of the Cyrenaica, of Africa proper, Numidia, and Mauritania,
+the thronging millions of Europe might still find room on the Eastern
+continent, and the main current of emigration be turned toward the
+rising instead of the setting sun.
+
+But changes like these must await great political and moral revolutions
+in the governments and peoples by whom those regions are now possessed,
+a command of pecuniary and of mechanical means not at present enjoyed by
+those nations, and a more advanced and generally diffused knowledge of
+the processes by which the amelioration of soil and climate is possible,
+than now anywhere exists. Until such circumstances shall conspire to
+favor the work of geographical regeneration, the countries I have
+mentioned, with here and there a local exception, will continue to sink
+into yet deeper desolation, and in the mean time, the American
+continent, Southern Africa, Australia, and the smaller oceanic islands,
+will be almost the only theatres where man is engaged, on a great scale,
+in transforming the face of nature.
+
+
+_Arrest of Physical Decay of New Countries._
+
+Comparatively short as is the period through which the colonization of
+foreign lands by European emigrants extends, great, and, it is to be
+feared, sometimes irreparable, injury has been already done in the
+various processes by which man seeks to subjugate the virgin earth; and
+many provinces, first trodden by the _homo sapiens Europae_ within the
+last two centuries, begin to show signs of that melancholy dilapidation
+which is now driving so many of the peasantry of Europe from their
+native hearths. It is evidently a matter of great moment, not only to
+the population of the states where these symptoms are manifesting
+themselves, but to the general interests of humanity, that this decay
+should be arrested, and that the future operations of rural husbandry
+and of forest industry, in districts yet remaining substantially in
+their native condition, should be so conducted as to prevent the
+widespread mischiefs which have been elsewhere produced by thoughtless
+or wanton destruction of the natural safeguards of the soil. This can be
+done only by the diffusion of knowledge on this subject among the
+classes that, in earlier days, subdued and tilled ground in which they
+had no vested rights, but who, in our time, own their woods, their
+pastures, and their ploughlands as a perpetual possession for them and
+theirs, and have, therefore, a strong interest in the protection of
+their domain against deterioration.
+
+
+_Forms and Formations most liable to Physical Degradation._
+
+The character and extent of the evils under consideration depend very
+much on climate and the natural forms and constitution of surface. If
+the precipitation, whether great or small in amount, be equally
+distributed through the seasons, so that there are neither torrential
+rains nor parching droughts, and if, further, the general inclination of
+ground be moderate, so that the superficial waters are carried off
+without destructive rapidity of flow, and without sudden accumulation in
+the channels of natural drainage, there is little danger of the
+degradation of the soil in consequence of the removal of forest or other
+vegetable covering, and the natural face of the earth may be considered
+as substantially permanent. These conditions are well exemplified in
+Ireland, in a great part of England, in extensive districts in Germany
+and France, and, fortunately, in an immense proportion of the valley of
+the Mississippi and the basin of the great American lakes, as well as in
+many parts of the continents of South America and of Africa.
+
+Destructive changes are most frequent in countries of irregular and
+mountainous surface, and in climates where the precipitation is confined
+chiefly to a single season, and where the year is divided into a wet and
+a dry period, as is the case throughout a great part of the Ottoman
+empire, and, more or less strictly, the whole Mediterranean basin. It is
+partly, though by no means entirely, owing to topographical and climatic
+causes that the blight, which has smitten the fairest and most fertile
+provinces of Imperial Rome, has spared Britannia, Germania, Pannonia,
+and M[oe]sia, the comparatively inhospitable homes of barbarous races,
+who, in the days of the Caesars, were too little advanced in civilized
+life to possess either the power or the will to wage that war against
+the order of nature which seems, hitherto, an almost inseparable
+condition precedent of high social culture, and of great progress in
+fine and mechanical art.[33]
+
+In mountainous countries, on the other hand, various causes combine to
+expose the soil to constant dangers. The rain and snow usually fall in
+greater quantity, and with much inequality of distribution; the snow on
+the summits accumulates for many months in succession, and then is not
+unfrequently almost wholly dissolved in a single thaw, so that the
+entire precipitation of months is in a few hours hurried down the flanks
+of the mountains, and through the ravines that furrow them; the natural
+inclination of the surface promotes the swiftness of the gathering
+currents of diluvial rain and of melting snow, which soon acquire an
+almost irresistible force, and power of removal and transportation; the
+soil itself is less compact and tenacious than that of the plains, and
+if the sheltering forest has been destroyed, it is confined by few of
+the threads and ligaments by which nature had bound it together, and
+attached it to the rocky groundwork. Hence every considerable shower
+lays bare its roods of rock, and the torrents sent down by the thaws of
+spring, and by occasional heavy discharges of the summer and autumnal
+rains, are seas of mud and rolling stones that sometimes lay waste, and
+bury beneath them acres, and even miles, of pasture and field and
+vineyard.[34]
+
+
+_Physical Decay of New Countries._
+
+I have remarked that the effects of human action on the forms of the
+earth's surface could not always be distinguished from those resulting
+from geological causes, and there is also much uncertainty in respect to
+the precise influence of the clearing and cultivating of the ground,
+and of other rural operations, upon climate. It is disputed whether
+either the mean or the extremes of temperature, the periods of the
+seasons, or the amount or distribution of precipitation and of
+evaporation, in any country whose annals are known, have undergone any
+change during the historical period. It is, indeed, impossible to doubt
+that many of the operations of the pioneer settler tend to produce great
+modifications in atmospheric humidity, temperature, and electricity; but
+we are at present unable to determine how far one set of effects is
+neutralized by another, or compensated by unknown agencies. This
+question scientific research is inadequate to solve, for want of the
+necessary data; but well conducted observation, in regions now first
+brought under the occupation of man, combined with such historical
+evidence as still exists, may be expected at no distant period to throw
+much light on this subject.
+
+Australia is, perhaps, the country from which we have a right to expect
+the fullest elucidation of these difficult and disputable problems. Its
+colonization did not commence until the physical sciences had become
+matter of almost universal attention, and is, indeed, so recent that the
+memory of living men embraces the principal epochs of its history; the
+peculiarities of its fauna, its flora, and its geology are such as to
+have excited for it the liveliest interest of the votaries of natural
+science; its mines have given its people the necessary wealth for
+procuring the means of instrumental observation, and the leisure
+required for the pursuit of scientific research; and large tracts of
+virgin forest and natural meadow are rapidly passing under the control
+of civilized man. Here, then, exist greater facilities and stronger
+motives for the careful study of the topics in question than have ever
+been found combined in any other theatre of European colonization.
+
+In North America, the change from the natural to the artificial
+condition of terrestrial surface began about the period when the most
+important instruments of meteorological observation were invented. The
+first settlers in the territory now constituting the United States and
+the British American provinces had other things to do than to tabulate
+barometrical and thermometrical readings, but there remain some
+interesting physical records from the early days of the colonies,[35]
+and there is still an immense extent of North American soil where the
+industry and the folly of man have as yet produced little appreciable
+change. Here, too, with the present increased facilities for scientific
+observation, the future effects, direct and contingent, of man's labors,
+can be measured, and such precautions taken in those rural processes
+which we call improvements, as to mitigate evils, perhaps, in some
+degree, inseparable from every attempt to control the action of natural
+laws.
+
+In order to arrive at safe conclusions, we must first obtain a more
+exact knowledge of the topography, and of the present superficial and
+climatic condition of countries where the natural surface is as yet more
+or less unbroken. This can only be accomplished by accurate surveys, and
+by a great multiplication of the points of meteorological registry,[36]
+already so numerous; and as, moreover, considerable changes in the
+proportion of forest and of cultivated land, or of dry and wholly or
+partially submerged surface, will often take place within brief periods,
+it is highly desirable that the attention of observers, in whose
+neighborhood the clearing of the soil, or the drainage of lakes and
+swamps, or other great works of rural improvement, are going on or
+meditated, should be especially drawn not only to revolutions in
+atmospheric temperature and precipitation, but to the more easily
+ascertained and perhaps more important local changes produced by these
+operations in the temperature and the hygrometric state of the
+superficial strata of the earth, and in its spontaneous vegetable and
+animal products.
+
+The rapid extension of railroads, which now everywhere keeps pace with,
+and sometimes even precedes, the occupation of new soil for agricultural
+purposes, furnishes great facilities for enlarging our knowledge of the
+topography of the territory they traverse, because their cuttings reveal
+the composition and general structure of surface, and the inclination
+and elevation of their lines constitute known hypsometrical sections,
+which give numerous points of departure for the measurement of higher
+and lower stations, and of course for determining the relief and
+depression of surface, the slope of the beds of watercourses, and many
+other not less important questions.[37]
+
+The geological, hydrographical, and topographical surveys, which almost
+every general and even local government of the civilized world is
+carrying on, are making yet more important contributions to our stock of
+geographical and general physical knowledge, and, within a comparatively
+short space, there will be an accumulation of well established constant
+and historical facts, from which we can safely reason upon all the
+relations of action and reaction between man and external nature.
+
+But we are, even now, breaking up the floor and wainscoting and doors
+and window frames of our dwelling, for fuel to warm our bodies and
+seethe our pottage, and the world cannot afford to wait till the slow
+and sure progress of exact science has taught it a better economy. Many
+practical lessons have been learned by the common observation of
+unschooled men; and the teachings of simple experience, on topics where
+natural philosophy has scarcely yet spoken, are not to be despised.
+
+In these humble pages, which do not in the least aspire to rank among
+scientific expositions of the laws of nature, I shall attempt to give
+the most important practical conclusions suggested by the history of
+man's efforts to replenish the earth and subdue it; and I shall aim to
+support those conclusions by such facts and illustrations only as
+address themselves to the understanding of every intelligent reader, and
+as are to be found recorded in works capable of profitable perusal, or
+at least consultation, by persons who have not enjoyed a special
+scientific training.
+
+
+
+
+CHAPTER II.
+
+TRANSFER, MODIFICATION, AND EXTIRPATION OF VEGETABLE AND OF ANIMAL
+SPECIES.
+
+MODERN GEOGRAPHY EMBRACES ORGANIC LIFE--TRANSFER OF VEGETABLE LIFE--
+FOREIGN PLANTS GROWN IN THE UNITED STATES--AMERICAN PLANTS GROWS IN
+EUROPE--MODES OF INTRODUCTION OF FOREIGN PLANTS--VEGETABLES, HOW
+AFFECTED BY TRANSFER TO FOREIGN SOILS--EXTIRPATION OF VEGETABLES--
+ORIGIN OF DOMESTIC PLANTS--ORGANIC LIFE AS A GEOLOGICAL AND GEOGRAPHICAL
+AGENCY--ORIGIN AND TRANSFER OF DOMESTIC ANIMALS--EXTIRPATION OF
+ANIMALS--NUMBERS OF BIRDS IN THE UNITED STATES--BIRDS AS SOWERS AND
+CONSUMERS OF SEEDS, AND AS DESTROYERS OF INSECTS--DIMINUTION AND
+EXTIRPATION OF BIRDS--INTRODUCTION OF BIRDS--UTILITY OF INSECTS AND
+WORMS--INTRODUCTION OF INSECTS--DESTRUCTION OF INSECTS--REPTILES--
+DESTRUCTION OF FISH--INTRODUCTION AND BREEDING OF FISH--EXTIRPATION
+OF AQUATIC ANIMALS--MINUTE ORGANISMS.
+
+
+_Modern Geography embraces Organic Life._
+
+It was a narrow view of geography which confined that science to
+delineation of terrestrial surface and outline, and to description of
+the relative position and magnitude of land and water. In its improved
+form, it embraces not only the globe itself, but the living things which
+vegetate or move upon it, the varied influences they exert upon each
+other, the reciprocal action and reaction between them and the earth
+they inhabit. Even if the end of geographical studies were only to
+obtain a knowledge of the external forms of the mineral and fluid masses
+which constitute the globe, it would still be necessary to take into
+account the element of life; for every plant, every animal, is a
+geographical agency, man a destructive, vegetables, and even wild
+beasts, restorative powers. The rushing waters sweep down earth from the
+uplands; in the first moment of repose, vegetation seeks to reestablish
+itself on the bared surface, and, by the slow deposit of its decaying
+products, to raise again the soil which the torrent had lowered. So
+important an element of reconstruction is this, that it has been
+seriously questioned whether, upon the whole, vegetation does not
+contribute as much to elevate, as the waters to depress, the level of
+the surface.
+
+Whenever man has transported a plant from its native habitat to a new
+soil, he has introduced a new geographical force to act upon it, and
+this generally at the expense of some indigenous growth which the
+foreign vegetable has supplanted. The new and the old plants are rarely
+the equivalents of each other, and the substitution of an exotic for a
+native tree, shrub, or grass, increases or diminishes the relative
+importance of the vegetable element in the geography of the country to
+which it is removed. Further, man sows that he may reap. The products of
+agricultural industry are not suffered to rot upon the ground, and thus
+raise it by an annual stratum of new mould. They are gathered,
+transported to greater or less distances, and after they have served
+their uses in human economy, they enter, on the final decomposition of
+their elements, into new combinations, and are only in small proportion
+returned to the soil on which they grew. The roots of the grasses, and
+of many other cultivated plants, however, usually remain and decay in
+the earth, and contribute to raise its surface, though certainly not in
+the same degree as the forest.
+
+The vegetables, which have taken the place of trees, unquestionably
+perform many of the same functions. They radiate heat, they condense the
+humidity of the atmosphere, they act upon the chemical constitution of
+the air, their roots penetrate the earth to greater depths than is
+commonly supposed, and form an inextricable labyrinth of filaments which
+bind the soil together and prevent its erosion by water. The
+broad-leaved annuals and perennials, too, shade the ground, and prevent
+the evaporation of moisture from its surface by wind and sun.[38] At a
+certain stage of growth, grass land is probably a more energetic
+radiator and condenser than even the forest, but this powerful action is
+exerted, in its full intensity, for a few days only, while trees
+continue such functions, with unabated vigor, for many months in
+succession. Upon the whole, it seems quite certain, that no cultivated
+ground is as efficient in tempering climatic extremes, or in
+conservation of geographical surface and outline, as is the soil which
+nature herself has planted.
+
+
+_Transfer of Vegetable Life._
+
+It belongs to vegetable and animal geography, which are almost sciences
+of themselves, to point out in detail what man has done to change the
+distribution of plants and of animated life and to revolutionize the
+aspect of organic nature; but some of the more important facts bearing
+on this subject may pertinently be introduced here. Most of the fruit
+trees grown in Europe and the United States are believed, and--if the
+testimony of Pliny and other ancient naturalists is to be depended
+upon--many of them are historically known, to have originated in the
+temperate climates of Asia. The wine grape has been thought to be truly
+indigenous only in the regions bordering on the eastern end of the Black
+Sea, where it now, particularly on the banks of the Rion, the ancient
+Phasis, propagates itself spontaneously, and grows with unexampled
+luxuriance.[39] But, some species of the vine seem native to Europe, and
+many varieties of grape have been too long known as common to every part
+of the United States to admit of the supposition that they were all
+introduced by European colonists.[40]
+
+It is an interesting fact that the commerce--or at least the maritime
+carrying trade--and the agricultural and mechanical industry of the
+world are, in very large proportion, dependent on vegetable and animal
+products little or not at all known to ancient Greek, Roman, and Jewish
+civilization. In many instances, the chief supply of these articles
+comes from countries to which they are probably indigenous, and where
+they are still almost exclusively grown; but in many others, the plants
+or animals from which they are derived have been introduced by man into
+the regions now remarkable for their most successful cultivation, and
+that, too, in comparatively recent times, or, in other words, within two
+or three centuries.
+
+
+_Foreign Plants grown in the United States._
+
+According to Bigelow, the United States had, on the first of June, 1860,
+in round numbers, 163,000,000 acres of improved land, the quantity
+having been increased by 50,000,000 acres within the ten years next
+preceding.[41] Not to mention less important crops, this land produced,
+in the year ending on the day last mentioned, in round numbers,
+171,000,000 bushels of wheat, 21,000,000 bushels of rye, 172,000,000
+bushels of oats, 15,000,000 bushels of pease and beans, 16,000,000
+bushels of barley, orchard fruits to the value of $20,000,000, 900,000
+bushels of cloverseed, 900,000 bushels of other grass seed, 104,000 tons
+of hemp, 4,000,000 pounds of flax, and 600,000 pounds of flaxseed. These
+vegetable growths were familiar to ancient European agriculture, but
+they were all introduced into North America after the close of the
+sixteenth century.
+
+Of the fruits of agricultural industry unknown to the Greeks and Romans,
+or too little employed by them to be of any commercial importance, the
+United States produced, in the same year, 187,000,000 pounds of rice,
+18,000,000 bushels of buckwheat, 2,075,000,000 pounds of ginned
+cotton,[42] 302,000,000 pounds of cane sugar, 16,000,000 gallons of
+cane molasses, 7,000,000 gallons of sorghum molasses, all yielded by
+vegetables introduced into that country within two hundred years,
+and--with the exception of buckwheat, the origin of which is uncertain,
+and of cotton--all, directly or indirectly, from the East Indies;
+besides, from indigenous plants unknown to ancient agriculture,
+830,000,000 bushels of Indian corn or maize, 429,000,000 pounds of
+tobacco, 110,000,000 bushels of potatoes, 42,000,000 bushels of sweet
+potatoes, 39,000,000 pounds of maple sugar, and 2,000,000 gallons of
+maple molasses. To all this we are to add 19,000,000 tons of hay,
+produced partly by new, partly by long known, partly by exotic, partly
+by native herbs and grasses, an incalculable quantity of garden
+vegetables, chiefly of European or Asiatic origin, and many minor
+agricultural products.
+
+The weight of this harvest of a year would be not less than 60,000,000
+tons--which is eleven times the tonnage of all the shipping of the
+United States at the close of the year 1861--and, with the exception of
+the maple sugar, the maple molasses, and the products of the Western
+prairie lands and some small Indian clearings, it was all grown upon
+lands wrested from the forest by the European race within little more
+than two hundred years. The wants of Europe have introduced into the
+colonies of tropical America the sugar cane, the coffee plant, the
+orange and the lemon,[43] all of Oriental origin, have immensely
+stimulated the cultivation of the former two in the countries of which
+they are natives, and, of course, promoted agricultural operations which
+must have affected the geography of those regions to an extent
+proportionate to the scale on which they have been pursued.
+
+
+_American Plants grown in Europe._
+
+America has partially repaid her debt to the Eastern continent. Maize
+and the potato are very valuable additions to the field agriculture of
+Europe and the East, and the tomato is no mean gift to the kitchen
+gardens of the Old World, though certainly not an adequate return for
+the multitude of esculent roots and leguminous plants which the European
+colonists carried with them.[44] I wish I could believe, with some, that
+America is not alone responsible for the introduction of the filthy
+weed, tobacco, the use of which is the most vulgar and pernicious habit
+engrafted by the semi-barbarism of modern civilization upon the less
+multifarious sensualism of ancient life;[45] but the alleged occurrence
+of pipe-like objects in Sclavonic, and, it has been said, in Hungarian
+sepulchres, is hardly sufficient evidence to convict those races of
+complicity in this grave offence against the temperance and the
+refinement of modern society.
+
+
+_Modes of Introduction of Foreign Plants._
+
+Besides the vegetables I have mentioned, we know that many plants of
+smaller economical value have been the subjects of international
+exchange in very recent times. Busbequius, Austrian ambassador at
+Constantinople about the middle of the sixteenth century--whose letters
+contain one of the best accounts of Turkish life which have appeared
+down to the present day--brought home from the Ottoman capital the lilac
+and the tulip. The Belgian Clusius about the same time introduced from
+the East the horse chestnut, which has since wandered to America. The
+weeping willows of Europe and the United States are said to have sprung
+from a slip received from Smyrna by the poet Pope, and planted by him in
+an English garden; and the Portuguese declare that the progenitor of all
+the European and American oranges was an Oriental tree transplanted to
+Lisbon, and still living in the last generation.[46] The present
+favorite flowers of the parterres of Europe have been imported from
+America, Japan and other remote Oriental countries, within a century and
+a half, and, in fine, there are few vegetables of any agricultural
+importance, few ornamental trees or decorative plants, which are not now
+common to the three civilized continents.
+
+The statistics of vegetable emigration exhibit numerical results quite
+surprising to those not familiar with the subject. The lonely island of
+St. Helena is described as producing, at the time of its discovery in
+the year 1501, about sixty vegetable species, including some three or
+four known to grow elsewhere also. At the present time its flora numbers
+seven hundred and fifty species. Humboldt and Bonpland found, among the
+unquestionably indigenous plants of tropical America, monocotyledons
+only, all the dicotyledons of those extensive regions having been
+probably introduced after the colonization of the New World by Spain.
+
+The faculty of spontaneous reproduction and perpetuation necessarily
+supposes a greater power of accommodation, within a certain range, than
+we find in most domesticated plants, for it would rarely happen that the
+seed of a wild plant would fall into ground as nearly similar, in
+composition and condition, to that where its parent grew, as the soils
+of different fields artificially prepared for growing a particular
+vegetable are to each other. Accordingly, though every wild species
+affects a habitat of a particular character, it is found that, if
+accidentally or designedly sown elsewhere, it will grow under conditions
+extremely unlike those of its birthplace.[47] Cooper says: "We cannot
+say positively that _any_ plant is _uncultivable_ anywhere until it has
+been tried;" and this seems to be even more true of wild than of
+domesticated vegetation.
+
+The seven hundred new species which have found their way to St. Helena
+within three centuries and a half, were certainly not all, or even in
+the largest proportion, designedly planted there by human art, and if we
+were well acquainted with vegetable emigration, we should probably be
+able to show that man has intentionally transferred fewer plants than he
+has accidentally introduced into countries foreign to them. After the
+wheat, follow the tares that infest it. The weeds that grow among the
+cereal grains, the pests of the kitchen garden, are the same in America
+as in Europe.[48] The overturning of a wagon, or any of the thousand
+accidents which befall the emigrant in his journey across the Western
+plains, may scatter upon the ground the seeds he designed for his
+garden, and the herbs which fill so important a place in the rustic
+materia medica of the Eastern States, spring up along the prairie paths
+but just opened by the caravan of the settler.[49] The hortus siccus of
+a botanist may accidentally sow seeds from the foot of the Himalayas on
+the plains that skirt the Alps; and it is a fact of very familiar
+observation, that exotics, transplanted to foreign climates suited to
+their growth, often escape from the flower garden and naturalize
+themselves among the spontaneous vegetation of the pastures. When the
+cases containing the artistic treasures of Thorvaldsen were opened in
+the court of the museum where they are deposited, the straw and grass
+employed in packing them were scattered upon the ground, and the next
+season there sprang up from the seeds no less than twenty-five species
+of plants belonging to the Roman campagna, some of which were preserved
+and cultivated as a new tribute to the memory of the great Scandinavian
+sculptor, and at least four are said to have spontaneously naturalized
+themselves about Copenhagen.[50] In the campaign of 1814, the Russian
+troops brought, in the stuffing of their saddles and by other accidental
+means, seeds from the banks of the Dnieper to the valley of the Rhine,
+and even introduced the plants of the steppes into the environs of
+Paris. The Turkish armies, in their incursions into Europe, brought
+Eastern vegetables in their train, and left the seeds of Oriental wall
+plants to grow upon the ramparts of Buda and Vienna.[51] The Canada
+thistle, _Erigeron Canadense_, is said to have sprung up in Europe, two
+hundred years ago, from a seed which dropped out of the stuffed skin of
+a bird.[52]
+
+
+_Vegetables, how affected by Transfer to Foreign Soils._
+
+Vegetables, naturalized abroad either by accident or design, sometimes
+exhibit a greatly increased luxuriance of growth. The European cardoon,
+an esculent thistle, has broken out from the gardens of the Spanish
+colonies on the La Plata, acquired a gigantic stature, and propagated
+itself, in impenetrable thickets, over hundreds of leagues of the
+Pampas; and the _Anacharis alsinastrum_, a water plant not much inclined
+to spread in its native American habitat, has found its way into English
+rivers, and extended itself to such a degree as to form a serious
+obstruction to the flow of the current, and even to navigation.
+
+Not only do many wild plants exhibit a remarkable facility of
+accommodation, but their seeds usually possess great tenacity of life,
+and their germinating power resists very severe trials. Hence, while the
+seeds of very many cultivated vegetables lose their vitality in two or
+three years, and can be transported safely to distant countries only
+with great precautions, the weeds that infest those vegetables, though
+not cared for by man, continue to accompany him in his migrations, and
+find a new home on every soil he colonizes. Nature fights in defence of
+her free children, but wars upon them when they have deserted her
+banners and tamely submitted to the dominion of man.[53]
+
+Not only is the wild plant much hardier than the domesticated vegetable,
+but the same law prevails in animated brute and even human life. The
+beasts of the chase are more capable of endurance and privation and more
+tenacious of life, than the domesticated animals which most nearly
+resemble them. The savage fights on, after he has received half a dozen
+mortal wounds, the least of which would have instantly paralyzed the
+strength of his civilized enemy, and, like the wild boar,[54] he has
+been known to press forward along the shaft of the spear which was
+transpiercing his vitals, and to deal a deathblow on the soldier who
+wielded it.
+
+True, domesticated plants can be gradually acclimatized to bear a degree
+of heat or of cold, which, in their wild state, they would not have
+supported; the trained English racer outstrips the swiftest horse of the
+pampas or prairies, perhaps even the less systematically educated
+courser of the Arab; the strength of the European, as tested by the
+dynamometer, is greater than that of the New Zealander. But all these
+are instances of excessive development of particular capacities and
+faculties at the expense of general vital power. Expose untamed and
+domesticated forms of life, together, to an entire set of physical
+conditions equally alien to the former habits of both, so that every
+power of resistance and accommodation shall be called into action, and
+the wild plant or animal will live, while the domesticated will perish.
+
+The saline atmosphere of the sea is specially injurious both to seeds
+and to very many young plants, and it is only recently that the
+transportation of some very important vegetables across the ocean has
+been made practicable, through the invention of Ward's airtight glass
+cases. It is by this means that large numbers of the trees which produce
+the Jesuit's bark have been successfully transplanted from America to
+the British possessions in the East, where it is hoped they will become
+fully naturalized.
+
+
+_Extirpation of Vegetables._
+
+Lamentable as are the evils produced by the too general felling of the
+woods in the Old World, I believe it does not satisfactorily appear that
+any species of native forest tree has yet been extirpated by man on the
+Eastern continent. The roots, stumps, trunks, and foliage found in bogs
+are recognized as belonging to still extant species. Except in some few
+cases where there is historical evidence that foreign material was
+employed, the timber of the oldest European buildings, and even of the
+lacustrine habitations of Switzerland, is evidently the product of trees
+still common in or near the countries where such architectural remains
+are found; nor have the Egyptian catacombs themselves revealed to us the
+former existence of any woods not now familiar to us as the growth of
+still living trees.[55] It is, however, said that the yew tree, _Taxus
+baccata_, formerly very common in England, Germany, and--as we are
+authorized to infer from Theophrastus--in Greece, has almost wholly
+disappeared from the latter country, and seems to be dying out in
+Germany. The wood of the yew surpasses that of any other European tree
+in closeness and fineness of grain, and it is well known for the
+elasticity which of old made it so great a favorite with the English
+archer. It is much in request among wood carvers and turners, and the
+demand for it explains, in part, its increasing scarcity. It is also
+worth remarking that no insect depends upon it for food or shelter, or
+aids in its fructification, no bird feeds upon its berries--the latter a
+circumstance of some importance, because the tree hence wants one means
+of propagation or diffusion common to so many other plants. But it is
+alleged that the reproductive power of the yew is exhausted, and that it
+can no longer be readily propagated by the natural sowing of its seeds,
+or by artificial methods. If further investigation and careful
+experiment should establish this fact, it will go far to show that a
+climatic change, of a character unfavorable to the growth of the yew,
+has really taken place in Germany, though not yet proved by instrumental
+observation, and the most probable cause of such change would be found
+in the diminution of the area covered by the forests.
+
+The industry of man is said to have been so successful in the local
+extirpation of noxious or useless vegetables in China, that, with the
+exception of a few water plants in the rice grounds, it is sometimes
+impossible to find a single weed in an extensive district; and the late
+eminent agriculturist, Mr. Coke, is reported to have offered in vain a
+considerable reward for the detection of a weed in a large wheatfield on
+his estate in England. In these cases, however, there is no reason to
+suppose that diligent husbandry has done more than to eradicate the
+pests of agriculture within a comparatively limited area, and the cockle
+and the darnel will probably remain to plague the slovenly cultivator as
+long as the cereal grains continue to bless him.[56]
+
+
+_Origin of Domestic Plants._
+
+One of the most important, and, at the same time, most difficult
+questions connected with our subject is: how far we are to regard our
+cereal grains, our esculent bulbs and roots, and the multiplied tree
+fruits of our gardens, as artificially modified and improved forms of
+wild, self-propagating vegetation. The narratives of botanical
+travellers have often announced the discovery of the original form and
+habitat of domesticated plants, and scientific journals have described
+the experiments by which the identity of particular wild and cultivated
+vegetables has been thought to be established. It is confidently
+affirmed that maize and the potato--which we must suppose to have been
+first cultivated at a much later period than the breadstuffs and most
+other esculent vegetables of Europe and the East--are found wild and
+self-propagating in Spanish America, though in forms not recognizable by
+the common observer as identical with the familiar corn and tuber of
+modern agriculture. It was lately asserted, upon what seemed very strong
+evidence, that the _AEgilops ovata_, a plant growing wild in Southern
+France, had been actually converted into common wheat; but, upon a
+repetition of the experiments, later observers have declared that the
+apparent change was only a case of temporary hybridation or fecundation
+by the pollen of true wheat, and that the grass alleged to be
+transformed into wheat could not be perpetuated as such from its own
+seed.
+
+The very great modifications which cultivated plants are constantly
+undergoing under our eyes, and the numerous varieties and races which
+spring up among them, certainly countenance the doctrine, that every
+domesticated vegetable, however dependent upon human care for growth and
+propagation in its present form, may have been really derived, by a long
+succession of changes, from some wild plant not now much resembling it.
+But it is, in every case, a question of evidence. The only satisfactory
+proof that a given wild plant is identical with a given garden or field
+vegetable, is the test of experiment, the actual growing of the one from
+the seed of the other, or the conversion of the one into the other by
+transplantation and change of conditions. It is hardly contended that
+any of the cereals or other plants important as human aliment, or as
+objects of agricultural industry, exist and propagate themselves
+uncultivated in the same form and with the same properties as when sown
+and reared by human art.[57] In fact, the cases are rare where the
+identity of a wild with a domesticated plant is considered by the best
+authorities as conclusively established, and we are warranted in
+affirming of but few of the latter, as a historically known or
+experimentally proved fact, that they ever did exist, or could exist,
+independently of man.[58]
+
+
+_Organic Life as a Geological and Geographical Agency._
+
+The quantitative value of organic life, as a geological agency, seems to
+be inversely as the volume of the individual organism; for nature
+supplies by numbers what is wanting in the bulk of the plant or animal
+out of whose remains or structures she forms strata covering whole
+provinces, and builds up from the depths of the sea large islands, if
+not continents. There are, it is true, near the mouths of the great
+Siberian rivers which empty themselves into the Polar Sea, drift islands
+composed, in an incredibly large proportion, of the bones and tusks of
+elephants, mastodons, and other huge pachyderms, and many extensive
+caves in various parts of the world are half filled with the skeletons
+of quadrupeds, sometimes lying loose in the earth, sometimes cemented
+together into an osseous breccia by a calcareous deposit or other
+binding material. These remains of large animals, though found in
+comparatively late formations, generally belong to extinct species, and
+their modern congeners or representatives do not exist in sufficient
+numbers to be of sensible importance in geology or in geography by the
+mere mass of their skeletons.[59] But the vegetable products found with
+them, and, in rare cases, in the stomachs of some of them, are those of
+yet extant plants; and besides this evidence, the recent discovery of
+works of human art, deposited in juxtaposition with fossil bones, and
+evidently at the same time and by the same agency which buried these
+latter--not to speak of alleged human bones found in the same
+strata--proves that the animals whose former existence they testify were
+contemporaneous with man, and possibly even extirpated by him.[60] I do
+not propose to enter upon the thorny question, whether the existing
+races of man are genealogically connected with these ancient types of
+humanity, and I advert to these facts only for the sake of the
+suggestion that man, in his earliest known stages of existence, was
+probably a destructive power upon the earth, though perhaps not so
+emphatically as his present representatives.
+
+The larger wild animals are not now numerous enough in any one region to
+form extensive deposits by their remains; but they have, nevertheless, a
+certain geographical importance. If the myriads of large browsing and
+grazing quadrupeds which wander over the plains of Southern Africa--and
+the slaughter of which by thousands is the source of a ferocious
+pleasure and a brutal triumph to professedly civilized hunters--if the
+herds of the American bison, which are numbered by hundreds of
+thousands, do not produce visible changes in the forms of terrestrial
+surface, they have at least an immense influence on the growth and
+distribution of vegetable life, and, of course, indirectly upon all the
+physical conditions of soil and climate between which and vegetation a
+mutual interdependence exists.
+
+The influence of wild quadrupeds upon vegetable life has been little
+studied, and not many facts bearing upon it have been recorded, but, so
+far as it is known, it appears to be conservative rather than
+pernicious.[61] Few if any of them depend for their subsistence on
+vegetable products obtainable only by the destruction of the plant, and
+they seem to confine their consumption almost exclusively to the annual
+harvest of leaf or twig, or at least of parts of the vegetable easily
+reproduced. If there are exceptions to this rule, they are in cases
+where the numbers of the animal are so proportioned to the abundance of
+the vegetable, that there is no danger of the extermination of the plant
+from the voracity of the quadruped, or of the extinction of the
+quadruped from the scarcity of the plant. In diet and natural wants the
+bison resembles the ox, the ibex and the chamois assimilate themselves
+to the goat and the sheep; but while the wild animal does not appear to
+be a destructive agency in the garden of nature, his domestic congeners
+are eminently so. This is partly from the change of habits resulting
+from domestication and association with man, partly from the fact that
+the number of reclaimed animals is not determined by the natural
+relation of demand and spontaneous supply which regulates the
+multiplication of wild creatures, but by the convenience of man, who is,
+in comparatively few things, amenable to the control of the merely
+physical arrangements of nature. When the domesticated animal escapes
+from human jurisdiction, as in the case of the ox, the horse, the goat,
+and perhaps the ass--which, so far as I know, are the only
+well-authenticated instances of the complete emancipation of household
+quadrupeds--he becomes again an unresisting subject of nature, and all
+his economy is governed by the same laws as that of his fellows which
+have never been enslaved by man; but, so long as he obeys a human lord,
+he is an auxiliary in the warfare his master is ever waging against all
+existences except those which he can tame to a willing servitude.
+
+
+_Number of Quadrupeds in the United States._
+
+Civilization is so intimately associated with, if not dependent upon,
+certain inferior forms of animal life, that cultivated man has never
+failed to accompany himself, in all his migrations, with some of these
+humble attendants. The ox, the horse, the sheep, and even the
+comparatively useless dog and cat, as well as several species of
+poultry, are voluntarily transported by every emigrant colony, and they
+soon multiply to numbers very far exceeding those of the wild genera
+most nearly corresponding to them.[62] According to the census of the
+United States for 1860,[63] the total number of horses in all the
+States of the American Union, was, in round numbers, 7,300,000; of asses
+and mules, 1,300,000; of the ox tribe, 29,000,000;[64] of sheep,
+25,000,000; and of swine, 39,000,000. The only North American quadruped
+sufficiently gregarious in habits, and sufficiently multiplied in
+numbers, to form really large herds, is the bison, or, as he is commonly
+called in America, the buffalo; and this animal is confined to the
+prairie region of the Mississippi basin and Northern Mexico. The
+engineers sent out to survey railroad routes to the Pacific estimated
+the number of a single herd of bisons seen within the last ten years on
+the great plains near the Upper Missouri, at not less than 200,000, and
+yet the range occupied by this animal is now very much smaller in area
+than it was when the whites first established themselves on the
+prairies.[65] But it must be remarked that the American buffalo is a
+migratory animal, and that, at the season of his annual journeys, the
+whole stock of a vast extent of pasture ground is collected into a
+single army, which is seen at or very near any one point only for a few
+days during the entire season. Hence there is risk of great error in
+estimating the numbers of the bison in a given district from the
+magnitude of the herds seen at or about the same time at a single place
+of observation; and, upon the whole, it is neither proved nor probable
+that the bison was ever, at any one time, as numerous in North America
+as the domestic bovine species is at present. The elk, the moose, the
+musk ox, the caribou, and the smaller quadrupeds popularly embraced
+under the general name of deer,[66] though sufficient for the wants of a
+sparse savage population, were never numerically very abundant, and the
+carnivora which fed upon them were still less so. It is almost needless
+to add that the Rocky Mountain sheep and goat must always have been very
+rare.
+
+Summing up the whole, then, it is evident that the wild quadrupeds of
+North America, even when most numerous, were few compared with their
+domestic successors, that they required a much less supply of vegetable
+food, and consequently were far less important as geographical elements
+than the many millions of hoofed and horned cattle now fed by civilized
+man on the same continent.
+
+
+_Origin and Transfer of Domestic Quadrupeds._
+
+Of the origin of our domestic animals, we know historically nothing,
+because their domestication belongs to the ages which preceded written
+history; but though they cannot all be specifically identified with now
+extant wild animals, it is presumable that they have been reclaimed from
+an originally wild state. Ancient annalists have preserved to us fewer
+data respecting the introduction of domestic animals into new countries
+than respecting the transplantation of domestic vegetables. Ritter, in
+his learned essay on the camel, has shown that this animal was not
+employed by the Egyptians until a comparatively late period in their
+history; that he was unknown to the Carthaginians until after the
+downfall of their commonwealth; and that his first appearance in Western
+Africa is more recent still. The Bactrian camel was certainly brought
+from Asia Minor to the Northern shores of the Black Sea, by the Goths,
+in the third or fourth century.[67] The Arabian single-humped camel, or
+dromedary, has been carried to the Canary Islands, partially introduced
+into Australia, Greece, Spain, and even Tuscany, experimented upon to
+little purpose in Venezuela, and finally imported by the American
+Government into Texas and New Mexico, where it finds the climate and the
+vegetable products best suited to its wants, and promises to become a
+very useful agent in the promotion of the special civilization for which
+those regions are adapted. America had no domestic quadruped but a
+species of dog, the lama tribe, and, to a certain extent, the bison or
+buffalo.[68] Of course, it owes the horse, the ass, the ox, the sheep,
+the goat, and the swine, as does also Australia, to European
+colonization. Modern Europe has, thus far, not accomplished much in the
+way of importation of new animals, though some interesting essays have
+been made. The reindeer was successfully introduced into Iceland about a
+century ago, while similar attempts failed, about the same time, in
+Scotland. The Cashmere or Thibet goat was brought to France a generation
+since, and succeeds well. The same or an allied species and the Asiatic
+buffalo were carried to South Carolina about the year 1850, and the
+former, at least, is thought likely to prove of permanent value in the
+United States. The yak, or Tartary ox, seems to thrive in France, and
+success has attended the recent efforts to introduce the South American
+alpaca into Europe.
+
+
+_Extirpation of Quadrupeds._
+
+Although man never fails greatly to diminish, and is perhaps destined
+ultimately to exterminate, such of the larger wild quadrupeds as he
+cannot profitably domesticate, yet their numbers often fluctuate, and
+even after they seem almost extinct, they sometimes suddenly increase,
+without any intentional steps to promote such a result on his part.
+During the wars which followed the French Revolution, the wolf
+multiplied in many parts of Europe, partly because the hunters were
+withdrawn from the woods to chase a nobler game, and partly because the
+bodies of slain men and horses supplied this voracious quadruped with
+more abundant food. The same animal became again more numerous in Poland
+after the general disarming of the rural population by the Russian
+Government. On the other hand, when the hunters pursue the wolf, the
+graminivorous wild quadrupeds increase, and thus in turn promote the
+multiplication of their great four-footed destroyer by augmenting the
+supply of his nourishment. So long as the fur of the beaver was
+extensively employed as a material for fine hats, it bore a very high
+price, and the chase of this quadruped was so keen that naturalists
+feared its speedy extinction. When a Parisian manufacturer invented the
+silk hat, which soon came into almost universal use, the demand for
+beavers' fur fell off, and this animal--whose habits, as we have seen,
+are an important agency in the formation of bogs and other modifications
+of forest nature--immediately began to increase, reappeared in haunts
+which he had long abandoned, and can no longer be regarded as rare
+enough to be in immediate danger of extirpation. Thus the convenience or
+the caprice of Parisian fashion has unconsciously exercised an influence
+which may sensibly affect the physical geography of a distant continent.
+
+Since the invention of gunpowder, some quadrupeds have completely
+disappeared from many European and Asiatic countries where they were
+formerly numerous. The last wolf was killed in Great Britain two hundred
+years ago, and the bear was extirpated from that island still earlier.
+The British wild ox exists only in a few English and Scottish parks,
+while in Irish bogs, of no great apparent antiquity, are found antlers
+which testify to the former existence of a stag much larger than any
+extant European species. The lion is believed to have inhabited Asia
+Minor and Syria, and probably Greece and Sicily also, long after the
+commencement of the historical period, and he is even said to have been
+not yet extinct in the first-named two of these countries at the time of
+the first Crusades.[69] Two large graminivorous or browsing quadrupeds,
+the ur and the schelk, once common in Germany, are utterly extinct, the
+eland and the auerochs nearly so. The Nibelungen-Lied, which, in the
+oldest form preserved to us, dates from about the year 1,200, though its
+original composition no doubt belongs to an earlier period, thus sings:
+
+ Then slowe the dowghtie Sigfrid a wisent and an elk,
+ He smote four stoute uroxen and a grim and sturdie schelk.[70]
+
+Modern naturalists identify the elk with the eland, the wisent with the
+auerochs. The period when the ur and the schelk became extinct is not
+known. The auerochs survived in Prussia until the middle of the last
+century, but unless it is identical with a similar quadruped said to be
+found on the Caucasus, it now exists only in the Russian imperial forest
+of Bialowitz, where about a thousand are still preserved, and in some
+great menageries, as for example that at Schoenbrunn, near Vienna, which,
+in 1852, had four specimens. The eland, which is closely allied to the
+American wapiti, if not specifically the same animal, is still kept in
+the royal preserves of Prussia, to the number of four or five hundred
+individuals. The chamois is becoming rare, and the ibex or steinbock,
+once common in all the high Alps, is now believed to be confined to the
+Cogne mountains in Piedmont, between the valleys of the Dora Baltea and
+the Orco.
+
+
+_Number of Birds in the United States._
+
+The tame fowls play a much less conspicuous part in rural life than the
+quadrupeds, and, in their relations to the economy of nature, they are
+of very much less moment than four-footed animals, or than the
+undomesticated birds. The domestic turkey[71] is probably more numerous
+in the territory of the United States than the wild bird of the same
+species ever was, and the grouse cannot, at the period of their greatest
+abundance, have counted as many as we now number of the common hen. The
+dove, however, must fall greatly short of the wild pigeon in multitude,
+and it is hardly probable that the flocks of domestic geese and ducks
+are as numerous as once were those of their wild congeners. The pigeon,
+indeed, seems to have multiplied immensely, for some years after the
+first clearings in the woods, because the settlers warred unsparingly
+upon the hawk, while the crops of grain and other vegetable growths
+increased the supply of food within the reach of the young birds, at the
+age when their power of flight is not yet great enough to enable them
+to seek it over a wide area.[72] The pigeon is not described by the
+earliest white inhabitants of the American States as filling the air
+with such clouds of winged life as astonish naturalists in the
+descriptions of Audubon, and, at the present day, the net and the gun
+have so reduced its abundance, that its appearance in large numbers is
+recorded only at long intervals, and it is never seen in the great
+flocks remembered by many still living observers as formerly very
+common.
+
+
+_Birds as Sowers and Consumers of Seeds, and as Destroyers of Insects._
+
+Wild birds form of themselves a very conspicuous and interesting feature
+in the _staffage_, as painters call it, of the natural landscape, and
+they are important elements in the view we are taking of geography,
+whether we consider their immediate or their incidental influence. Birds
+affect vegetation directly by sowing seeds and by consuming them; they
+affect it indirectly by destroying insects injurious, or, in some cases,
+beneficial to vegetable life. Hence, when we kill a seed-sowing bird, we
+check the dissemination of a plant; when we kill a bird which digests
+the seed it swallows, we promote the increase of a vegetable. Nature
+protects the seeds of wild, much more effectually than those of
+domesticated plants. The cereal grains are completely digested when
+consumed by birds, but the germ of the smaller stone fruits and of very
+many other wild vegetables is uninjured, perhaps even stimulated to more
+vigorous growth, by the natural chemistry of the bird's stomach. The
+power of flight and the restless habits of the bird enable it to
+transport heavy seeds to far greater distances than they could be
+carried by the wind. A swift-winged bird may drop cherry stones a
+thousand miles from the tree they grow on; a hawk, in tearing a pigeon,
+may scatter from its crop the still fresh rice it had swallowed at a
+distance of ten degrees of latitude,[73] and thus the occurrence of
+isolated plants in situations where their presence cannot otherwise well
+be explained, is easily accounted for. There is a large class of seeds
+apparently specially fitted by nature for dissemination by animals. I
+refer to those which attach themselves, by means of hooks, or by viscous
+juices, to the coats of quadrupeds and the feathers of birds, and are
+thus transported wherever their living vehicles may chance to wander.
+Some birds, too, deliberately bury seeds, not indeed with a foresight
+aiming directly at the propagation of the plant, but from apparently
+purposeless secretiveness, or as a mode of preserving food for future
+use.
+
+An unfortunate popular error greatly magnifies the injury done to the
+crops of grain and leguminous vegetables by wild birds. Very many of
+those generally supposed to consume large quantities of the seeds of
+cultivated plants really feed almost exclusively upon insects, and
+frequent the wheatfields, not for the sake of the grain, but for the
+eggs, larvae, and fly of the multiplied tribes of insect life which are
+so destructive to the harvests. This fact has been so well established
+by the examination of the stomachs of great numbers of birds in Europe
+and New England, at different seasons of the year, that it is no longer
+open to doubt, and it appears highly probable that even the species
+which consume more or less grain generally make amends, by destroying
+insects whose ravages would have been still more injurious.[74] On this
+subject, we have much other evidence besides that derived from
+dissection. Direct observation has shown, in many instances, that the
+destruction of wild birds has been followed by a great multiplication of
+noxious insects, and, on the other hand, that these latter have been
+much reduced in numbers by the protection and increase of the birds that
+devour them. Many interesting facts of this nature have been collected
+by professed naturalists, but I shall content myself with a few taken
+from familiar and generally accessible sources. The following extract is
+from Michelet, _L'Oiseau_ pp. 169, 170:
+
+"The _stingy_ farmer--an epithet justly and feelingly bestowed by
+Virgil. Avaricious, blind, indeed, who proscribes the birds--those
+destroyers of insects, those defenders of his harvests. Not a grain for
+the creature which, during the rains of winter, hunts the future insect,
+finds out the nests of the larvae, examines, turns over every leaf, and
+destroys, every day, thousands of incipient caterpillars. But sacks of
+corn for the mature insect, whole fields for the grasshoppers, which the
+bird would have made war upon. With eyes fixed upon his furrow, upon the
+present moment only, without seeing and without foreseeing, blind to the
+great harmony which is never broken with impunity, he has everywhere
+demanded or approved laws for the extermination of that necessary ally
+of his toil--the insectivorous bird. And the insect has well avenged the
+bird. It has become necessary to revoke in haste the proscription. In
+the Isle of Bourbon, for instance, a price was set on the head of the
+martin; it disappeared, and the grasshoppers took possession of the
+island, devouring, withering, scorching with a biting drought all that
+they did not consume. In North America it has been the same with the
+starling, the protector of Indian corn.[75] Even the sparrow, which
+really does attack grain, but which protects it still more, the
+pilferer, the outlaw, loaded with abuse and smitten with curses--it has
+been found in Hungary that they were likely to perish without him, that
+he alone could sustain the mighty war against the beetles and the
+thousand winged enemies that swarm in the lowlands; they have revoked
+the decree of banishment, recalled in haste this valiant militia, which,
+though deficient in discipline, is nevertheless the salvation of the
+country.[76]
+
+"Not long since, in the neighborhood of Rouen and in the valley of
+Monville, the blackbird was for some time proscribed. The beetles
+profited well by this proscription; their larvae, infinitely multiplied,
+carried on their subterranean labors with such success, that a meadow
+was shown me, the surface of which was completely dried up, every
+herbaceous root was consumed, and the whole grassy mantle, easily
+loosened, might have been rolled up and carried away like a carpet."
+
+
+_Diminution and Extirpation of Birds._
+
+The general hostility of the European populace to the smaller birds is,
+in part, the remote effect of the reaction created by the game laws.
+When the restrictions imposed upon the chase by those laws were suddenly
+removed in France, the whole people at once commenced a destructive
+campaign against every species of wild animal. Arthur Young, writing in
+Provence, on the 30th of August, 1789, soon after the National Assembly
+had declared the chase free, thus complains of the annoyance he
+experienced from the use made by the peasantry of their newly won
+liberty. "One would think that every rusty firelock in all Provence was
+at work in the indiscriminate destruction of all the birds. The wadding
+buzzed by my ears, or fell into my carriage, five or six times in the
+course of the day." * * "The declaration of the Assembly that every man
+is free to hunt on his own land * * has filled all France with an
+intolerable cloud of sportsmen. * * The declaration speaks of
+compensations and indemnities [to the _seigneurs_], but the ungovernable
+populace takes advantage of the abolition of the game laws and laughs at
+the obligation imposed by the decree."
+
+The French Revolution removed similar restrictions, with similar
+results, in other countries. The habits then formed have become
+hereditary on the Continent, and though game laws still exist in
+England, there is little doubt that the blind prejudices of the ignorant
+and half-educated classes in that country against birds are, in some
+degree, at least, due to a legislation, which, by restricting the chase
+of all game worth killing, drives the unprivileged sportsman to
+indemnify himself by slaughtering all wild life which is not reserved
+for the amusement of his betters. Hence the lord of the manor buys his
+partridges and his hares by sacrificing the bread of his tenants, and so
+long as the farmers of Crawley are forbidden to follow higher game, they
+will suicidally revenge themselves by destroying the sparrows which
+protect their wheatfields.
+
+On the Continent, and especially in Italy, the comparative scarcity and
+dearness of animal food combine with the feeling I have just mentioned
+to stimulate still further the destructive passions of the fowler. In
+the Tuscan province of Grosseto, containing less than 2,000 square
+miles, nearly 300,000 thrushes and other small birds are annually
+brought to market.[77]
+
+Birds are less hardy in constitution, they possess less facility of
+accommodation,[78] and they are more severely affected by climatic
+excess than quadrupeds. Besides, they generally want the means of
+shelter against the inclemency of the weather and against pursuit by
+their enemies, which holes and dens afford to burrowing animals and to
+some larger beasts of prey. The egg is exposed to many dangers before
+hatching, and the young bird is especially tender, defenceless, and
+helpless. Every cold rain, every violent wind, every hailstorm during
+the breeding season, destroys hundreds of nestlings, and the parent
+often perishes with her progeny while brooding over it in the vain
+effort to protect it.[79] The great proportional numbers of birds, their
+migratory habits, and the ease with which they may escape most dangers
+that beset them, would seem to secure them from extirpation, and even
+from very great numerical reduction. But experience shows that when not
+protected by law, by popular favor or superstition, or by other special
+circumstances, they yield very readily to the hostile influences of
+civilization, and, though the first operations of the settler are
+favorable to the increase of many species, the great extension of rural
+and of mechanical industry is, in a variety of ways, destructive even to
+tribes not directly warred upon by man.[80]
+
+Nature sets bounds to the disproportionate increase of birds, while at
+the same time, by the multitude of their resources, she secures them
+from extinction through her own spontaneous agencies. Man both preys
+upon them and wantonly destroys them. The delicious flavor of game
+birds, and the skill implied in the various arts of the sportsman who
+devotes himself to fowling, make them favorite objects of the chase,
+while the beauty of their plumage, as a military and feminine
+decoration, threatens to involve the sacrifice of the last survivor of
+many once numerous species. Thus far, but few birds described by ancient
+or modern naturalists are known to have become absolutely extinct,
+though there are some cases in which they are ascertained to have
+utterly disappeared from the face of the earth in very recent times. The
+most familiar instances are those of the dodo, a large bird peculiar to
+the Mauritius or Isle of France, exterminated about the year 1690, and
+now known only by two or three fragments of skeletons, and the solitary,
+which inhabited the islands of Bourbon and Rodriguez, but has not been
+seen for more than a century. A parrot and some other birds of the
+Norfolk Island group are said to have lately become extinct. The
+wingless auk, _Alca impennis_, a bird remarkable for its excessive
+fatness, was very abundant two or three hundred years ago in the Faroe
+Islands, and on the whole Scandinavian seaboard. The early voyagers
+found either the same or a closely allied species, in immense numbers,
+on all the coasts and islands of Newfoundland. The value of its flesh
+and its oil made it one of the most important resources of the
+inhabitants of those sterile regions, and it was naturally an object of
+keen pursuit. It is supposed to be now completely extinct, and few
+museums can show even its skeleton.
+
+There seems to be strong reason to believe that our boasted modern
+civilization is guiltless of one or two sins of extermination which have
+been committed in recent ages. New Zealand formerly possessed three
+species of dinornis, one of which, called _moa_ by the islanders, was
+much larger than the ostrich. The condition in which the bones of these
+birds have been found and the traditions of the natives concur to prove
+that, though the aborigines had probably extirpated them before the
+discovery of New Zealand by the whites, they still existed at a
+comparatively late period. The same remarks apply to a winged giant the
+eggs of which have been brought from Madagascar. This bird must have
+much exceeded the dimensions of the moa, at least so far as we can judge
+from the egg, which is eight times as large as the average size of the
+ostrich egg, or about one hundred and fifty times that of the hen.
+
+But though we have no evidence that man has exterminated many species of
+birds, we know that his persecutions have caused their disappearance
+from many localities where they once were common, and greatly diminished
+their numbers in others. The cappercailzie, _Tetrao urogallus_, the
+finest of the grouse family, formerly abundant in Scotland, had become
+extinct in Great Britain, but has been reintroduced from Sweden.[81] The
+ostrich is mentioned by all the old travellers, as common on the
+Isthmus of Suez down to the middle of the seventeenth century. It
+appears to have frequented Syria and even Asia Minor at earlier periods,
+but is now found only in the seclusion of remoter deserts.
+
+The modern increased facilities of transportation have brought distant
+markets within reach of the professional hunter, and thereby given a new
+impulse to his destructive propensities. Not only do all Great Britain
+and Ireland contribute to the supply of game for the British capital,
+but the canvas-back duck of the Potomac, and even the prairie hen from
+the basin of the Mississippi, may be found at the stalls of the London
+poulterer. Kohl[82] informs us that on the coasts of the North Sea,
+twenty thousand wild ducks are usually taken in the course of the season
+in a single decoy, and sent to the large maritime towns for sale. The
+statistics of the great European cities show a prodigious consumption of
+game birds, but the official returns fall far below the truth, because
+they do not include the rural districts, and because neither the poacher
+nor his customers report the number of his victims. Reproduction, in
+cultivated countries, cannot keep pace with this excessive destruction,
+and there is no doubt that all the wild birds which are chased for their
+flesh or their plumage are diminishing with a rapidity which justifies
+the fear that the last of them will soon follow the dodo and the
+wingless auk.
+
+Fortunately the larger birds which are pursued for their flesh or for
+their feathers, and those the eggs of which are used as food, are, so
+far as we know the functions appointed to them by nature, not otherwise
+specially useful to man, and, therefore, their wholesale destruction is
+an economical evil only in the same sense in which all waste of
+productive capital is an evil. If it were possible to confine the
+consumption of game fowl to a number equal to the annual increase, the
+world would be a gainer, but not to the same extent as it would be by
+checking the wanton sacrifice of millions of the smaller birds, which
+are of no real value as food, but which, as we have seen, render a most
+important service by battling, in our behalf, as well as in their own,
+against the countless legions of humming and of creeping things, with
+which the prolific powers of insect life would otherwise cover the
+earth.
+
+
+_Introduction of Birds._
+
+Man has undesignedly introduced into new districts perhaps fewer species
+of birds than of quadrupeds; but the distribution of birds is very much
+influenced by the character of his industry, and the transplantation of
+every object of agricultural production is, at a longer or shorter
+interval, followed by that of the birds which feed upon its seeds, or
+more frequently upon the insects it harbors. The vulture, the crow, and
+other winged scavengers, follow the march of armies as regularly as the
+wolf. Birds accompany ships on long voyages, for the sake of the offal
+which is thrown overboard, and, in such cases, it might often happen
+that they would breed and become naturalized in countries where they had
+been unknown before.[83] There is a familiar story of an English bird
+which built its nest in an unused block in the rigging of a ship, and
+made one or two short voyages with the vessel while hatching its eggs.
+Had the young become fledged while lying in a foreign harbor, they would
+of course have claimed the rights of citizenship in the country where
+they first took to the wing.[84]
+
+Some enthusiastic entomologist will, perhaps, by and by discover that
+insects and worms are as essential as the larger organisms to the proper
+working of the great terraqueous machine, and we shall have as eloquent
+pleas in defence of the mosquito, and perhaps even of the tzetze fly, as
+Toussenel and Michelet have framed in behalf of the bird.[85] The
+silkworm and the bee need no apologist; a gallnut produced by the
+puncture of an insect on a Syrian oak is a necessary ingredient in the
+ink I am writing with, and from my windows I recognize the grain of the
+kermes and the cochineal in the gay habiliments of the holiday groups
+beneath them. But agriculture, too, is indebted to the insect and the
+worm. The ancients, according to Pliny, were accustomed to hang
+branches of the wild fig upon the domestic tree, in order that the
+insects which frequented the former might hasten the ripening of the
+cultivated fig by their punctures--or, as others suppose, might fructify
+it by transporting to it the pollen of the wild fruit--and this process,
+called caprification, is not yet entirely obsolete. The earthworms long
+ago made good their title to the respect and gratitude of the farmer as
+well as of the angler. The utility of the earthworms has been pointed
+out in many scientific as well as in many agricultural treatises. The
+following extract, cut from a newspaper, will answer my present purpose:
+
+"Mr. Josiah Parkes, the consulting engineer of the Royal Agricultural
+Society of England, says that worms are great assistants to the drainer,
+and valuable aids to the farmer in keeping up the fertility of the soil.
+He says they love moist, but not wet soils; they will bore down to, but
+not into water; they multiply rapidly on land after drainage, and prefer
+a deeply dried soil. On examining with Mr. Thomas Hammond, of Penhurst,
+Kent, part of a field which he had deeply drained, after long-previous
+shallow drainage, he found that the worms had greatly increased in
+number, and that their bores descended quite to the level of the pipes.
+Many worm bores were large enough to receive the little finger. Mr.
+Henry Handley had informed him of a piece of land near the sea in
+Lincolnshire, over which the sea had broken and killed all the
+worms--the field remained sterile until the worms again inhabited it. He
+also showed him a piece of pasture land near to his house, in which
+worms were in such numbers that he thought their casts interfered too
+much with its produce, which induced him to have it rolled at night in
+order to destroy the worms. The result was, that the fertility of the
+field greatly declined, nor was it restored until they had recruited
+their numbers, which was aided by collecting and transporting multitudes
+of worms from the fields.
+
+"The great depth into which worms will bore, and from which they push up
+fine fertile soil, and cast it on the surface, has been admirably traced
+by Mr. C. Darwin, of Down, Kent, who has shown that in a few years they
+have actually elevated the surface of fields by a large layer of rich
+mould, several inches thick--thus affording nourishment to the roots of
+grasses, and increasing the productiveness of the soil."
+
+It should be added that the writer quoted, and others who have discussed
+the subject, have overlooked one very important element in the
+fertilization produced by earthworms. I refer to the enrichment of the
+soil by their excreta during life, and by the decomposition of their
+remains when they die. The manure thus furnished is as valuable as the
+like amount of similar animal products derived from higher organisms,
+and when we consider the prodigious numbers of these worms found on a
+single square yard of some soils, we may easily see that they furnish no
+insignificant contribution to the nutritive material required for the
+growth of plants.[86]
+
+The perforations of the earthworm mechanically affect the texture of the
+soil and its permeability by water, and they therefore have a certain
+influence on the form and character of surface. But the geographical
+importance of insects proper, as well as of worms, depends principally
+on their connection with vegetable life as agents of its fecundation,
+and of its destruction.[87] I am acquainted with no single fact so
+strikingly illustrative of this importance, as the following statement
+which I take from a notice of Darwin's volume, On Various Contrivances
+by which British and Foreign Orchids are Fertilized by Insects, in the
+_Saturday Review_, of October 18, 1862: "The net result is, that some
+six thousand species of orchids are absolutely dependent upon the agency
+of insects for their fertilization. That is to say, were those plants
+unvisited by insects, they would all rapidly disappear." What is true of
+the orchids is more or less true of many other vegetable families. We do
+not know the limits of this agency, and many of the insects habitually
+regarded as unqualified pests, may directly or indirectly perform
+functions as important to the most valuable plants as the services
+rendered by certain tribes to the orchids. I say directly or indirectly,
+because, besides the other arrangements of nature for checking the undue
+multiplication of particular species, she has established a police among
+insects themselves, by which some of them keep down or promote the
+increase of others; for there are insects, as well as birds and beasts,
+of prey. The existence of an insect which fertilizes a useful vegetable
+may depend on that of another, which constitutes his food in some stage
+of his life, and this other again may be as injurious to some plant as
+his destroyer is beneficial to another. The equation of animal and
+vegetable life is too complicated a problem for human intelligence to
+solve, and we can never know how wide a circle of disturbance we produce
+in the harmonies of nature when we throw the smallest pebble into the
+ocean of organic life.
+
+This much, however, we seem authorized to conclude: as often as we
+destroy the balance by deranging the original proportions between
+different orders of spontaneous life, the law of self-preservation
+requires us to restore the equilibrium, by either directly returning the
+weight abstracted from one scale, or removing a corresponding quantity
+from the other. In other words, destruction must be either repaired by
+reproduction, or compensated by new destruction in an opposite quarter.
+
+The parlor aquarium has taught even those to whom it is but an amusing
+toy, that the balance of animal and vegetable life must be preserved,
+and that the excess of either is fatal to the other, in the artificial
+tank as well as in natural waters. A few years ago, the water of the
+Cochituate aqueduct at Boston became so offensive in smell and taste as
+to be quite unfit for use. Scientific investigation found the cause in
+the too scrupulous care with which aquatic vegetation had been excluded
+from the reservoir, and the consequent death and decay of the animalculae
+which could not be shut out, nor live in the water without the vegetable
+element.[88]
+
+
+_Introduction of Insects._
+
+The general tendency of man's encroachments upon spontaneous nature has
+been to increase insect life at the expense of vegetation and of the
+smaller quadrupeds and birds. Doubtless there are insects in all woods,
+but in temperate climates they are comparatively few and harmless, and
+the most numerous tribes which breed in the forest, or rather in its
+waters, and indeed in all solitudes, are those which little injure
+vegetation, such as mosquitoes, gnats, and the like. With the cultivated
+plants of man come the myriad tribes which feed or breed upon them, and
+agriculture not only introduces new species, but so multiplies the
+number of individuals as to defy calculation. Newly introduced
+vegetables frequently escape for years the insect plagues which had
+infested them in their native habitat; but the importation of other
+varieties of the plant, the exchange of seed, or some mere accident, is
+sure in the long run to carry the egg, the larva, or the chrysalis to
+the most distant shores where the plant assigned to it by nature as its
+possession has preceded it. For many years after the colonization of the
+United States, few or none of the insects which attack wheat in its
+different stages of growth, were known in America. During the
+Revolutionary war, the Hessian fly, _Cecidomyia destructor_, made its
+appearance, and it was so called because it was first observed in the
+year when the Hessian troops were brought over, and was popularly
+supposed to have been accidentally imported by those unwelcome
+strangers. Other destroyers of cereal grains have since found their way
+across the Atlantic, and a noxious European aphis has first attacked the
+American wheatfields within the last four or five years. Unhappily, in
+these cases of migration, the natural corrective of excessive
+multiplication, the parasitic or voracious enemy of the noxious insect,
+does not always accompany the wanderings of its prey, and the bane long
+precedes the antidote. Hence, in the United States, the ravages of
+imported insects injurious to cultivated crops, not being checked by the
+counteracting influences which nature had provided to limit their
+devastations in the Old World, are much more destructive than in Europe.
+It is not known that the wheat midge is preyed upon in America by any
+other insect, and in seasons favorable to it, it multiplies to a degree
+which would prove almost fatal to the entire harvest, were it not that,
+in the great territorial extent of the United States, there is room for
+such differences of soil and climate as, in a given year, to present in
+one State all the conditions favorable to the increase of a particular
+insect, while in another, the natural influences are hostile to it. The
+only apparent remedy for this evil is, to balance the disproportionate
+development of noxious foreign species by bringing from their native
+country the tribes which prey upon them. This, it seems, has been
+attempted. The United States' Census Report for 1860, p. 82, states that
+the New York Agricultural Society "has introduced into this country from
+abroad certain parasites which Providence has created to counteract the
+destructive powers of some of these depredators."
+
+This is, however, not the only purpose for which man has designedly
+introduced foreign forms of insect life. The eggs of the silkworm are
+known to have been brought from the farther East to Europe in the sixth
+century, and new silk spinners which feed on the castor oil bean and the
+ailanthus, have recently been reared in France and in South America with
+promising success. The cochineal, long regularly bred in aboriginal
+America, has been transplanted to Spain, and both the kermes insect and
+the cantharides have been transferred to other climates than their own.
+The honey bee must be ranked next to the silkworm in economical
+importance.[89] This useful creature was carried to the United States
+by European colonists, in the latter part of the seventeenth century; it
+did not cross the Mississippi till the close of the eighteenth, and it
+is only within the last five or six years that it has been transported
+to California, where it was previously unknown. The Italian stingless
+bee has very lately been introduced into the United States.
+
+The insects and worms intentionally transplanted by man bear but a small
+proportion to those accidentally introduced by him. Plants and animals
+often carry their parasites with them, and the traffic of commercial
+countries, which exchange their products with every zone and every stage
+of social existence, cannot fail to transfer in both directions the
+minute organisms that are, in one way or another, associated with almost
+every object important to the material interests of man.[90]
+
+The tenacity of life possessed by many insects, their prodigious
+fecundity, the length of time they often remain in the different phases
+of their existence,[91] the security of the retreats into which their
+small dimensions enable them to retire, are all circumstances very
+favorable not only to the perpetuity of their species, but to their
+transportation to distant climates and their multiplication in their new
+homes. The teredo, so destructive to shipping, has been carried by the
+vessels whose wooden walls it mines to almost every part of the globe.
+The termite, or white ant, is said to have been brought to Rochefort by
+the commerce of that port a hundred years ago.[92] This creature is more
+injurious to wooden structures and implements than any other known
+insect. It eats out almost the entire substance of the wood, leaving
+only thin partitions between the galleries it excavates in it; but as it
+never gnaws through the surface to the air, a stick of timber may be
+almost wholly consumed without showing any external sign of the damage
+it has sustained. The termite is found also in other parts of France,
+and particularly at Rochelle, where, thus far, its ravages are confined
+to a single quarter of the city. A borer, of similar habits, is not
+uncommon in Italy, and you may see in that country, handsome chairs and
+other furniture which have been reduced by this insect to a framework of
+powder of post, covered, and apparently held together, by nothing but
+the varnish.
+
+The carnivorous, and often the herbivorous insects render an important
+service to man by consuming dead and decaying animal and vegetable
+matter, the decomposition of which would otherwise fill the air with
+effluvia noxious to health. Some of them, the grave-digger beetle, for
+instance, bury the small animals in which they lay their eggs, and
+thereby prevent the escape of the gases disengaged by putrefaction. The
+prodigious rapidity of development in insect life, the great numbers of
+the individuals in many species, and the voracity of most of them while
+in the larva state, justify the appellation of nature's scavengers which
+has been bestowed upon them, and there is very little doubt that, in
+warm countries, they consume a much larger quantity of putrescent
+organic material than the quadrupeds and the birds which feed upon such
+aliment.
+
+
+_Destruction of Insects._
+
+It is well known to naturalists, but less familiarly to common
+observers, that the aquatic larvae of some insects constitute, at certain
+seasons, a large part of the food of fresh-water fish, while other
+larvae, in their turn, prey upon the spawn and even the young of their
+persecutors.[93] The larvae of the mosquito and the gnat are the favorite
+food of the trout in the wooded regions where those insects abound.[94]
+Earlier in the year the trout feeds on the larvae of the May fly, which
+is itself very destructive to the spawn of the salmon, and hence, by a
+sort of house-that-Jack-built, the destruction of the mosquito, that
+feeds the trout that preys on the May fly that destroys the eggs that
+hatch the salmon that pampers the epicure, may occasion a scarcity of
+this latter fish in waters where he would otherwise be abundant. Thus
+all nature is linked together by invisible bonds, and every organic
+creature, however low, however feeble, however dependent, is necessary
+to the well-being of some other among the myriad forms of life with
+which the Creator has peopled the earth.
+
+I have said that man has promoted the increase of the insect and the
+worm, by destroying the bird and the fish which feed upon them. Many
+insects, in the four different stages of their growth, inhabit in
+succession the earth, the water, and the air. In each of these elements
+they have their special enemies, and, deep and dark as are the minute
+recesses in which they hide themselves, they are pursued to the
+remotest, obscurest corners by the executioners that nature has
+appointed to punish their delinquencies, and furnished with cunning
+contrivances for ferreting out the offenders and dragging them into the
+light of day. One tribe of birds, the woodpeckers, seems to depend for
+subsistence almost wholly on those insects which breed in dead or dying
+trees, and it is, perhaps, needless to say that the injury these birds
+do the forest is imaginary. They do not cut holes in the trunk of the
+tree to prepare a lodgment for a future colony of boring larvae, but to
+extract the worm which has already begun his mining labors. Hence these
+birds are not found where the forester removes trees as fast as they
+become fit habitations for such insects. In clearing new lands in the
+United States, dead trees, especially of the spike-leaved kinds, too
+much decayed to serve for timber, and which, in that state, are worth
+little for fuel, are often allowed to stand until they fall of
+themselves. Such _stubs_, as they are popularly called, are filled with
+borers, and often deeply cut by the woodpeckers, whose strong bills
+enable them to penetrate to the very heart of the tree and drag out the
+lurking larvae. After a few years, the stubs fall, or, as wood becomes
+valuable, are cut and carried off for firewood, and, at the same time,
+the farmer selects for felling, in the forest he has reserved as a
+permanent source of supply of fuel and timber, the decaying trees which,
+like the dead stems in the fields, serve as a home for both the worm and
+his pursuer. We thus gradually extirpate this tribe of insects, and,
+with them, the species of birds which subsist principally upon them.
+Thus the fine, large, red-headed woodpecker, _Picus erythrocephalus_,
+formerly very common in New England, has almost entirely disappeared
+from those States, since the dead trees are gone, and the apples, his
+favorite vegetable food, are less abundant.
+
+There are even large quadrupeds which feed almost exclusively upon
+insects. The ant bear is strong enough to pull down the clay houses
+built by the species of termites that constitute his ordinary diet, and
+the curious ai-ai, a climbing quadruped of Madagascar--of which I
+believe only a single specimen, secured by Mr. Sandwith, has yet reached
+Europe--is provided with a very slender, hook-nailed finger, long enough
+to reach far into a hole in the trunk of a tree, and extract the worm
+which bored it.
+
+
+_Reptiles._
+
+But perhaps the most formidable foes of the insect, and even of the
+small rodents, are the reptiles. The chameleon approaches the insect
+perched upon the twig of a tree, with an almost imperceptible slowness
+of motion, until, at the distance of a foot, he shoots out his long,
+slimy tongue, and rarely fails to secure the victim. Even the slow toad
+catches the swift and wary housefly in the same manner; and in the warm
+countries of Europe, the numerous lizards contribute very essentially to
+the reduction of the insect population, which they both surprise in the
+winged state upon walls and trees, and consume as egg, worm, and
+chrysalis, in their earlier metamorphoses. The serpents feed much upon
+insects, as well as upon mice, moles, and small reptiles, including also
+other snakes. The disgust and fear with which the serpent is so
+universally regarded expose him to constant persecution by man, and
+perhaps no other animal is so relentlessly sacrificed by him. In
+temperate climates, snakes are consumed by scarcely any beast or bird of
+prey except the stork, and they have few dangerous enemies but man,
+though in the tropics other animals prey upon them.[95] It is doubtful
+whether any species of serpent has been exterminated within the human
+period, and even the dense population of China has not been able
+completely to rid itself of the viper. They have, however, almost
+entirely disappeared from particular localities. The rattlesnake is now
+wholly unknown in many large districts where it was extremely common
+half a century ago, and Palestine has long been, if not absolutely free
+from venomous serpents, at least very nearly so.[96]
+
+
+_Destruction of Fish._
+
+The inhabitants of the waters seem comparatively secure from human
+pursuit or interference by the inaccessibility of their retreats, and by
+our ignorance of their habits--a natural result of the difficulty of
+observing the ways of creatures living in a medium in which we cannot
+exist. Human agency has, nevertheless, both directly and incidentally,
+produced great changes in the population of the sea, the lakes, and the
+rivers, and if the effects of such revolutions in aquatic life are
+apparently of small importance in general geography, they are still not
+wholly inappreciable. The great diminution in the abundance of the
+larger fish employed for food or pursued for products useful in the arts
+is familiar, and when we consider how the vegetable and animal life on
+which they feed must be affected by the reduction of their numbers, it
+is easy to see that their destruction may involve considerable
+modifications in many of the material arrangements of nature. The whale
+does not appear to have been an object of pursuit by the ancients, for
+any purpose, nor do we know when the whale fishery first commenced.[97]
+It was, however, very actively prosecuted in the Middle Ages, and the
+Biscayans seem to have been particularly successful in this as indeed in
+other branches of nautical industry.[98] Five hundred years ago, whales
+abounded in every sea. They long since became so rare in the
+Mediterranean as not to afford encouragement for the fishery as a
+regular occupation; and the great demand for oil and whalebone for
+mechanical and manufacturing purposes, in the present century, has
+stimulated the pursuit of the "hugest of living creatures" to such
+activity, that he has now almost wholly disappeared from many favorite
+fishing grounds, and in others is greatly diminished in numbers.
+
+What special functions, besides his uses to man, are assigned to the
+whale in the economy of nature, we do not know; but some considerations,
+suggested by the character of the food upon which certain species
+subsist, deserve to be specially noticed. None of the great mammals
+grouped under the general name of whale are rapacious. They all live
+upon small organisms, and the most numerous species feed almost wholly
+upon the soft gelatinous mollusks in which the sea abounds in all
+latitudes. We cannot calculate even approximately the number of the
+whales, or the quantity of organic nutriment consumed by an individual,
+and of course we can form no estimate of the total amount of animal
+matter withdrawn by them, in a given period, from the waters of the sea.
+It is certain, however, that it must have been enormous when they were
+more abundant, and that it is still very considerable. A very few years
+since, the United States had more than six hundred whaling ships
+constantly employed in the Pacific, and the product of the American
+whale fishery for the year ending June 1st, 1860, was seven millions and
+a half of dollars.[99] The mere bulk of the whales destroyed in a single
+year by the American and the European vessels engaged in this fishery
+would form an island of no inconsiderable dimensions, and each one of
+those taken must have consumed, in the course of his growth, many times
+his own weight of mollusks. The destruction of the whales must have been
+followed by a proportional increase of the organisms they feed upon, and
+if we had the means of comparing the statistics of these humble forms of
+life, for even so short a period as that between the years 1760 and
+1860, we should find a difference sufficient, possibly, to suggest an
+explanation of some phenomena at present unaccounted for.
+
+For instance, as I have observed in another work,[100] the
+phosphorescence of the sea was unknown to ancient writers, or at least
+scarcely noticed by them, and even Homer--who, blind as tradition makes
+him when he composed his epics, had seen, and marked, in earlier life,
+all that the glorious nature of the Mediterranean and its coasts
+discloses to unscientific observation--nowhere alludes to this most
+beautiful and striking of maritime wonders. In the passage just referred
+to, I have endeavored to explain the silence of ancient writers with
+respect to this as well as other remarkable phenomena on psychological
+grounds; but is it not possible that, in modern times, the animalculae
+which produce it may have immensely multiplied, from the destruction of
+their natural enemies by man, and hence that the gleam shot forth by
+their decomposition, or by their living processes, is both more frequent
+and more brilliant than in the days of classic antiquity?
+
+Although the whale does not prey upon smaller creatures resembling
+himself in form and habits, yet true fishes are extremely voracious, and
+almost every tribe devours unsparingly the feebler species, and even
+the spawn and young of its own. The enormous destruction of the pike,
+the trout family, and other ravenous fish, as well as of the fishing
+birds, the seal, and the otter, by man, would naturally have occasioned
+a great increase in the weaker and more defenceless fish on which they
+feed, had he not been as hostile to them also as to their persecutors.
+We have little evidence that any fish employed as human food has
+naturally multiplied in modern times, while all the more valuable tribes
+have been immensely reduced in numbers.[101] This reduction must have
+affected the more voracious species not used as food by man, and
+accordingly the shark, and other fish of similar habits, though not
+objects of systematic pursuit, are now comparatively rare in many waters
+where they formerly abounded. The result is, that man has greatly
+reduced the numbers of all larger marine animals, and consequently
+indirectly favored the multiplication of the smaller aquatic organisms
+which entered into their nutriment. This change in the relations of the
+organic and inorganic matter of the sea must have exercised an influence
+on the latter. What that influence has been, we cannot say, still less
+can we predict what it will be hereafter; but its action is not for that
+reason the less certain.
+
+
+_Introduction and Breeding of Fish._
+
+The introduction and successful breeding of fish of foreign species
+appears to have been long practised in China and was not unknown to the
+Greeks and Romans. This art has been revived in modern times, but thus
+far without any important results, economical or physical, though there
+seems to be good reason to believe it may be employed with advantage on
+an extended scale. As in the case of plants, man has sometimes
+undesignedly introduced new species of aquatic animals into countries
+distant from their birthplace. The accidental escape of the Chinese
+goldfish from ponds where they were bred as a garden ornament, has
+peopled some European, and it is said American streams with this
+species. Canals of navigation and irrigation interchange the fish of
+lakes and rivers widely separated by natural barriers, as well as the
+plants which drop their seeds into the waters. The Erie Canal, as
+measured by its own channel, has a length of about three hundred and
+sixty miles, and it has ascending and descending locks in both
+directions. By this route, the fresh-water fish of the Hudson and the
+Upper Lakes, and some of the indigenous vegetables of these respective
+basins, have intermixed, and the fauna and flora of the two regions have
+now more species common to both than before the canal was opened. Some
+accidental attraction not unfrequently induces fish to follow a vessel
+for days in succession, and they may thus be enticed into zones very
+distant from their native habitat. Several years ago, I was told at
+Constantinople, upon good authority, that a couple of fish, of a species
+wholly unknown to the natives, had just been taken in the Bosphorus.
+They were alleged to have followed an English ship from the Thames, and
+to have been frequently observed by the crew during the passage, but I
+was unable to learn their specific character.
+
+Many of the fish which pass the greater part of the year in salt water
+spawn in fresh, and some fresh-water species, the common brook trout of
+New England for instance, which, under ordinary circumstances, never
+visit the sea, will, if transferred to brooks emptying directly into the
+ocean, go down into the salt water after spawning time, and return again
+the next season. Sea fish, the smelt among others, are said to have been
+naturalized in fresh water, and some naturalists have argued from the
+character of the fish of Lake Baikal, and especially from the existence
+of the seal in that locality, that all its inhabitants were originally
+marine species, and have changed their habits with the gradual
+conversion of the saline waters of the lake--once, as is assumed, a
+maritime bay--into fresh.[102] The presence of the seal is hardly
+conclusive on this point, for it is sometimes seen in Lake Champlain at
+the distance of some hundreds of miles from even brackish water. One of
+these animals was killed on the ice in that lake in February, 1810,
+another in February, 1846,[103] and remains of the seal have been found
+at other times in the same waters.
+
+The remains of the higher orders of aquatic animals are generally so
+perishable that, even where most abundant, they do not appear to be now
+forming permanent deposits of any considerable magnitude; but it is
+quite otherwise with shell fish, and, as we shall see hereafter, with
+many of the minute limeworkers of the sea. There are, on the southern
+coast of the United States, beds of shells so extensive that they were
+formerly supposed to have been naturally accumulated, and were appealed
+to as proofs of an elevation of the coast by geological causes; but they
+are now ascertained to have been derived from oysters, consumed in the
+course of long ages by the inhabitants of Indian towns. The planting of
+a bed of oysters in a new locality might, very probably, lead, in time,
+to the formation of a bank, which, in connection with other deposits,
+might perceptibly affect the line of a coast, or, by changing the course
+of marine currents, or the outlet of a river, produce geographical
+changes of no small importance. The transplantation of oysters to
+artificial ponds has long been common, and it appears to have recently
+succeeded well on a large scale in the open sea on the French coast. A
+great extension of this fishery is hoped for, and it is now proposed to
+introduce upon the same coast the American soft clam, which is so
+abundant in the tide-washed beach sands of Long Island Sound as to form
+an important article in the diet of the neighboring population.
+
+The intentional naturalization of foreign fish, as I have said, has not
+thus far yielded important fruits; but though this particular branch of
+what is called, not very happily, _pisciculture_, has not yet
+established its claims to the attention of the physical geographer or
+the political economist, the artificial breeding of domestic fish has
+already produced very valuable results, and is apparently destined to
+occupy an extremely conspicuous place in the history of man's efforts to
+compensate his prodigal waste of the gifts of nature. The restoration of
+the primitive abundance of salt and fresh water fish, is one of the
+greatest material benefits that, with our present physical resources,
+governments can hope to confer upon their subjects. The rivers, lakes,
+and seacoasts once restocked, and protected by law from exhaustion by
+taking fish at improper seasons, by destructive methods, and in
+extravagant quantities, would continue indefinitely to furnish a very
+large supply of most healthful food, which, unlike all domestic and
+agricultural products, would spontaneously renew itself and cost nothing
+but the taking. There are many sterile or wornout soils in Europe so
+situated that they might, at no very formidable cost, be converted into
+permanent lakes, which would serve not only as reservoirs to retain the
+water of winter rains and snow, and give it out in the dry season for
+irrigation, but as breeding ponds for fish, and would thus, without
+further cost, yield a larger supply of human food than can at present be
+obtained from them even at a great expenditure of capital and labor in
+agricultural operations. The additions which might be made to the
+nutriment of the civilized world by a judicious administration of the
+resources of the waters, would allow some restriction of the amount of
+soil at present employed for agricultural purposes, and a corresponding
+extension of the area of the forest, and would thus facilitate a return
+to primitive geographical arrangements which it is important partially
+to restore.
+
+
+_Extirpation of Aquatic Animals._
+
+It does not seem probable that man, with all his rapacity and all his
+enginery, will succeed in totally extirpating any salt-water fish, but
+he has already exterminated at least one marine warm-blooded
+animal--Steller's sea cow--and the walrus, the sea lion, and other large
+amphibia, as well as the principal fishing quadrupeds, are in imminent
+danger of extinction. Steller's sea cow, _Rhytina Stelleri_, was first
+seen by Europeans in the year 1741, on Bering's Island. It was a huge
+amphibious mammal, weighing not less than eight thousand pounds, and
+appears to have been confined exclusively to the islands and coasts in
+the neighborhood of Bering's Strait. Its flesh was very palatable, and
+the localities it frequented were easily accessible from the Russian
+establishments in Kamtschatka. As soon as its existence and character,
+and the abundance of fur animals in the same waters, were made known to
+the occupants of those posts by the return of the survivors of Bering's
+expedition, so active a chase was commenced against the amphibia of that
+region, that, in the course of twenty-seven years, the sea cow,
+described by Steller as extremely numerous in 1741, is believed to have
+been completely extirpated, not a single individual having been seen
+since the year 1768. The various tribes of seals in the Northern and
+Southern Pacific, the walrus and the sea otter, are already so reduced
+in numbers that they seem destined soon to follow the sea cow, unless
+protected by legislation stringent enough, and a police energetic
+enough, to repress the ardent cupidity of their pursuers.
+
+The seals, the otter tribe, and many other amphibia which feed almost
+exclusively upon fish, are extremely voracious, and of course their
+destruction or numerical reduction must have favored the multiplication
+of the species of fish principally preyed upon by them. I have been
+assured by the keeper of several tamed seals that, if supplied at
+frequent intervals, each seal would devour not less than fourteen pounds
+of fish, or about a quarter of his own weight, in a day.[104] A very
+intelligent and observing hunter, who has passed a great part of his
+life in the forest, after carefully watching the habits of the
+fresh-water otter of the Northern American States, estimates their
+consumption of fish at about four pounds per day.
+
+Man has promoted the multiplication of fish by making war on their brute
+enemies, but he has by no means thereby compensated his own greater
+destructiveness.[105] The bird and beast of prey, whether on land or in
+the water, hunt only as long as they feel the stimulus of hunger, their
+ravages are limited by the demands of present appetite, and they do not
+wastefully destroy what they cannot consume. Man, on the contrary,
+angles to-day that he may dine to-morrow; he takes and dries millions of
+fish on the banks of Newfoundland, that the fervent Catholic of the
+shores of the Mediterranean may have wherewithal to satisfy the cravings
+of the stomach during next year's Lent, without imperilling his soul by
+violating the discipline of the papal church; and all the arrangements
+of his fisheries are so organized as to involve the destruction of many
+more fish than are secured for human use, and the loss of a large
+proportion of the annual harvest of the sea in the process of curing, or
+in transportation to the places of its consumption.[106]
+
+Fish are more affected than quadrupeds by slight and even imperceptible
+differences in their breeding places and feeding grounds. Every river,
+every brook, every lake stamps a special character upon its salmon, its
+shad, and its trout, which is at once recognized by those who deal in or
+consume them. No skill can give the fish fattened by food selected and
+prepared by man the flavor of those which are nourished at the table of
+nature, and the trout of the artificial ponds in Germany and Switzerland
+are so inferior to the brook fish of the same species and climate, that
+it is hard to believe them identical. The superior sapidity of the
+American trout to the European species, which is familiar to every one
+acquainted with both continents, is probably due less to specific
+difference than to the fact that, even in the parts of the New World
+which have been longest cultivated, wild nature is not yet tamed down to
+the character it has assumed in the Old, and which it will acquire in
+America also when her civilization shall be as ancient as is now that of
+Europe.
+
+Man has hitherto hardly anywhere produced such climatic or other changes
+as would suffice of themselves totally to banish the wild inhabitants of
+the dry land, and the disappearance of the native birds and quadrupeds
+from particular localities is to be ascribed quite as much to his direct
+persecutions as to the want of forest shelter, of appropriate food, or
+of other conditions indispensable to their existence. But almost all the
+processes of agriculture, and of mechanical and chemical industry, are
+fatally destructive to aquatic animals within reach of their influence.
+When, in consequence of clearing the woods, the changes already
+described as thereby produced in the beds and currents of rivers, are in
+progress, the spawning grounds of fish are exposed from year to year to
+a succession of mechanical disturbances; the temperature of the water is
+higher in summer, colder in winter, than when it was shaded and
+protected by wood; the smaller organisms, which formed the sustenance of
+the young fry, disappear or are reduced in numbers, and new enemies are
+added to the old foes that preyed upon them; the increased turbidness of
+the water in the annual inundations chokes the fish; and, finally, the
+quickened velocity of its current sweeps them down into the larger
+rivers or into the sea, before they are yet strong enough to support so
+great a change of circumstances.[107] Industrial operations are not
+less destructive to fish which live or spawn in fresh water. Milldams
+impede their migrations, if they do not absolutely prevent them, the
+sawdust from lumber mills clogs their gills, and the thousand
+deleterious mineral substances, discharged into rivers from
+metallurgical, chemical, and manufacturing establishments, poison them
+by shoals.
+
+
+_Minute Organisms._
+
+Besides the larger creatures of the land and of the sea, the quadrupeds,
+the reptiles, the birds, the amphibia, the crustacea, the fish, the
+insects, and the worms, there are other countless forms of vital being.
+Earth, water, the ducts and fluids of vegetable and of animal life, the
+very air we breathe, are peopled by minute organisms which perform most
+important functions in both the living and the inanimate kingdoms of
+nature. Of the offices assigned to these creatures, the most familiar to
+common observation is the extraction of lime, and more rarely, of silex,
+from the waters inhabited by them, and the deposit of these minerals in
+a solid form, either as the material of their habitations or as the
+exuviae of their bodies. The microscope and other means of scientific
+observation assure us that the chalk beds of England and of France, the
+coral reefs of marine waters in warm climates, vast calcareous and
+silicious deposits in the sea and in many fresh-water ponds, the common
+polishing earths and slates, and many species of apparently dense and
+solid rock, are the work of the humble organisms of which I speak,
+often, indeed, of animalculae so small as to become visible only by the
+aid of lenses magnifying a hundred times the linear measures. It is
+popularly supposed that animalculae, or what are commonly embraced under
+the vague name of infusoria, inhabit the water alone, but the
+atmospheric dust transported by every wind and deposited by every calm
+is full of microscopic life or of its relics. The soil on which the city
+of Berlin stands, contains at the depth of ten or fifteen feet below the
+surface, living elaborators of silex;[108] and a microscopic examination
+of a handful of earth connected with the material evidences of guilt has
+enabled the naturalist to point out the very spot where a crime was
+committed. It has been computed that one sixth part of the solid matter
+let fall by great rivers at their outlets consists of still recognizable
+infusory shells and shields, and, as the friction of rolling water must
+reduce much of these fragile structures to a state of comminution which
+even the microscope cannot resolve into distinct particles and identify
+as relics of animal or of vegetable life, we must conclude that a
+considerably larger proportion of river deposits is really the product
+of animalcules.[109]
+
+It is evident that the chemical, and in many cases the mechanical
+character of a great number of the objects important in the material
+economy of human life, must be affected by the presence of so large an
+organic element in their substance, and it is equally obvious that all
+agricultural and all industrial operations tend to disturb the natural
+arrangements of this element, to increase or to diminish the special
+adaptation of every medium in which it lives to the particular orders
+of being inhabited by it. The conversion of woodland into pasturage, of
+pasture into plough land, of swamp or of shallow sea into dry ground,
+the rotations of cultivated crops, must prove fatal to millions of
+living things upon every rood of surface thus deranged by man, and must,
+at the same time, more or less fully compensate this destruction of life
+by promoting the growth and multiplication of other tribes equally
+minute in dimensions.
+
+I do not know that man has yet endeavored to avail himself, by
+artificial contrivances, of the agency of these wonderful architects and
+manufacturers. We are hardly well enough acquainted with their natural
+economy to devise means to turn their industry to profitable account,
+and they are in very many cases too slow in producing visible results
+for an age so impatient as ours. The over-civilization of the nineteenth
+century cannot wait for wealth to be amassed by infinitesimal gains, and
+we are in haste to _speculate_ upon the powers of nature, as we do upon
+objects of bargain and sale in our trafficking one with another. But
+there are still some cases where the little we know of a life, whose
+workings are invisible to the naked eye, suggests the possibility of
+advantageously directing the efforts of troops of artisans that we
+cannot see. Upon coasts occupied by the corallines, the reef-building
+animalcule does not work near the mouth of rivers. Hence the change of
+the outlet of a stream, often a very easy matter, may promote the
+construction of a barrier to coast navigation at one point, and check
+the formation of a reef at another, by diverting a current of fresh
+water from the former and pouring it into the sea at the latter. Cases
+may probably be found in tropical seas, where rivers have prevented the
+working of the coral animalcules in straits separating islands from each
+other or from the mainland. The diversion of such streams might remove
+this obstacle, and reefs consequently be formed which should convert an
+archipelago into a single large island, and finally join that to the
+neighboring continent.
+
+Quatrefages proposed to destroy the teredo in harbors by impregnating
+the water with a mineral solution fatal to them. Perhaps the labors of
+the coralline animals might be arrested over a considerable extent of
+sea coast by similar means. The reef builders are leisurely architects,
+but the precious coral is formed so rapidly that the beds may be
+refished advantageously as often as once in ten years.[110] It does not
+seem impossible that this coral might be transplanted to the American
+coast, where the Gulf stream would furnish a suitable temperature beyond
+the climatic limits that otherwise confine its growth; and thus a new
+source of profit might perhaps be added to the scanty returns of the
+hardy fisherman.
+
+In certain geological formations, the diatomaceae deposit, at the bottom
+of fresh-water ponds, beds of silicious shields, valuable as a material
+for a species of very light firebrick, in the manufacture of water glass
+and of hydraulic cement, and ultimately, doubtless, in many yet
+undiscovered industrial processes. An attentive study of the conditions
+favorable to the propagation of the diatomaceae might perhaps help us to
+profit directly by the productivity of this organism, and, at the same
+time, disclose secrets of nature capable of being turned to valuable
+account in dealing with silicious rocks, and the metal which is the base
+of them. Our acquaintance with the obscure and infinitesimal life of
+which I have now been treating is very recent, and still very imperfect.
+We know that it is of vast importance in the economy of nature, but we
+are so ambitious to grasp the great, so little accustomed to occupy
+ourselves with the minute, that we are not yet prepared to enter
+seriously upon the question how far we can control and direct the
+operations, not of unembodied physical forces, but of beings, in popular
+apprehension, almost as immaterial as they.
+
+Nature has no unit of magnitude by which she measures her works. Man
+takes his standards of dimension from himself. The hair's breadth was
+his minimum until the microscope told him that there are animated
+creatures to which one of the hairs of his head is a larger cylinder
+than is the trunk of the giant California redwood to him. He borrows his
+inch from the breadth of his thumb, his palm and span from the width of
+his hand and the spread of his fingers, his foot from the length of the
+organ so named; his cubit is the distance from the tip of his middle
+finger to his elbow, and his fathom is the space he can measure with his
+outstretched arms. To a being who instinctively finds the standard of
+all magnitudes in his own material frame, all objects exceeding his own
+dimensions are absolutely great, all falling short of them absolutely
+small. Hence we habitually regard the whale and the elephant as
+essentially large and therefore important creatures, the animalcule as
+an essentially small and therefore unimportant organism. But no
+geological formation owes its origin to the labors or the remains of the
+huge mammal, while the animalcule composes, or has furnished, the
+substance of strata thousands of feet in thickness, and extending, in
+unbroken beds, over many degrees of terrestrial surface. If man is
+destined to inhabit the earth much longer, and to advance in natural
+knowledge with the rapidity which has marked his progress in physical
+science for the last two or three centuries, he will learn to put a
+wiser estimate on the works of creation, and will derive not only great
+instruction from studying the ways of nature in her obscurest, humblest
+walks, but great material advantage from stimulating her productive
+energies in provinces of her empire hitherto regarded as forever
+inaccessible, utterly barren.[111]
+
+
+
+
+CHAPTER III.
+
+THE WOODS.
+
+THE HABITABLE EARTH ORIGINALLY WOODED--THE FOREST DOES NOT FURNISH
+FOOD FOR MAN--FIRST REMOVAL OF THE WOODS--EFFECTS OF FIRE ON FOREST
+SOIL--EFFECTS OF THE DESTRUCTION OF THE FOREST--ELECTRICAL INFLUENCE
+OF TREES--CHEMICAL INFLUENCE OF THE FOREST.
+
+INFLUENCE OF THE FOREST, CONSIDERED AS INORGANIC MATTER, ON TEMPERATURE:
+_a_, ABSORBING AND EMITTING SURFACE; _b_, TREES AS CONDUCTORS OF HEAT;
+_c_, TREES IN SUMMER AND IN WINTER; _d_, DEAD PRODUCTS OF TREES; _e_,
+TREES AS A SHELTER TO GROUNDS TO THE LEEWARD OF THEM; _f_, TREES AS A
+PROTECTION AGAINST MALARIA--THE FOREST, AS INORGANIC MATTER, TENDS TO
+MITIGATE EXTREMES.
+
+TREES AS ORGANISMS: SPECIFIC TEMPERATURE--TOTAL INFLUENCE OF THE FOREST
+ON TEMPERATURE.
+
+INFLUENCE OF FORESTS ON THE HUMIDITY OF THE AIR AND THE EARTH:
+_a_, AS INORGANIC MATTER; _b_, AS ORGANIC--WOOD MOSSES AND FUNGI--
+FLOW OF SAP--ABSORPTION AND EXHALATION OF MOISTURE BY TREES--BALANCE
+OF CONFLICTING INFLUENCES--INFLUENCE OF THE FOREST ON TEMPERATURE AND
+PRECIPITATION--INFLUENCE OF THE FOREST ON THE HUMIDITY OF THE SOIL--
+ITS INFLUENCE ON THE FLOW OF SPRINGS--GENERAL CONSEQUENCES OF THE
+DESTRUCTION OF THE WOODS--LITERATURE AND CONDITION OF THE FOREST IN
+DIFFERENT COUNTRIES--THE INFLUENCE OF THE FOREST ON INUNDATIONS--
+DESTRUCTIVE ACTION OF TORRENTS--THE PO AND ITS DEPOSITS--MOUNTAIN
+SLIDES--PROTECTION AGAINST THE FALL OF ROCKS AND AVALANCHES BY
+TREES--PRINCIPAL CAUSES OF THE DESTRUCTION OF THE FOREST--AMERICAN
+FOREST TREES--SPECIAL CAUSES OF THE DESTRUCTION OF EUROPEAN WOODS--
+ROYAL FORESTS AND GAME LAWS--SMALL FOREST PLANTS, VITALITY OF SEEDS--
+UTILITY OF THE FOREST--THE FORESTS OF EUROPE--FORESTS OF THE UNITED
+STATES AND CANADA--THE ECONOMY OF THE FOREST--EUROPEAN AND AMERICAN
+TREES COMPARED--SYLVICULTURE--INSTABILITY OF AMERICAN LIFE.
+
+
+_The Habitable Earth Originally Wooded._
+
+There is good reason to believe that the surface of the habitable earth,
+in all the climates and regions which have been the abodes of dense and
+civilized populations, was, with few exceptions, already covered with a
+forest growth when it first became the home of man. This we infer from
+the extensive vegetable remains--trunks, branches, roots, fruits, seeds,
+and leaves of trees--so often found in conjunction with works of
+primitive art, in the boggy soil of districts where no forests appear to
+have existed within the eras through which written annals reach; from
+ancient historical records, which prove that large provinces, where the
+earth has long been wholly bare of trees, were clothed with vast and
+almost unbroken woods when first made known to Greek and Roman
+civilization;[112] and from the state of much of North and of South
+America when they were discovered and colonized by the European
+race.[113]
+
+These evidences are strengthened by observation of the natural economy
+of our own time; for, whenever a tract of country, once inhabited and
+cultivated by man, is abandoned by him and by domestic animals,[114] and
+surrendered to the undisturbed influences of spontaneous nature, its
+soil sooner or later clothes itself with herbaceous and arborescent
+plants, and at no long interval, with a dense forest growth. Indeed,
+upon surfaces of a certain stability, and not absolutely precipitous
+inclination, the special conditions required for the spontaneous
+propagation of trees may all be negatively expressed and reduced to
+these three: exemption from defect or excess of moisture, from perpetual
+frost, and from the depredations of man and browsing quadrupeds. Where
+these requisites are secured, the hardest rock is as certain to be
+overgrown with wood as the most fertile plain, though, for obvious
+reasons, the process is slower in the former than in the latter case.
+Lichens and mosses first prepare the way for a more highly organized
+vegetation. They retain the moisture of rains and dews, and bring it to
+act, in combination with the gases evolved by their organic processes,
+in decomposing the surface of the rocks they cover; they arrest and
+confine the dust which the wind scatters over them, and their final
+decay adds new material to the soil already half formed beneath and upon
+them. A very thin stratum of mould is sufficient for the germination of
+seeds of the hardy evergreens and birches, the roots of which are often
+found in immediate contact with the rock, supplying their trees with
+nourishment from a soil derived from the decomposition of their own
+foliage, or sending out long rootlets into the surrounding earth in
+search of juices to feed them.
+
+The eruptive matter of volcanoes, forbidding as is its aspect, does not
+refuse nutriment to the woods. The refractory lava of Etna, it is true,
+remains long barren, and that of the great eruption of 1669 is still
+almost wholly devoid of vegetation.[115] But the cactus is making
+inroads even here, while the volcanic sand and molten rock thrown out by
+Vesuvius soon becomes productive. George Sandys, who visited this
+latter mountain in 1611, after it had reposed for several centuries,
+found the throat of the volcano at the bottom of the crater "almost
+choked with broken rocks and _trees_ that are falne therein." "Next to
+this," he continues, "the matter thrown up is ruddy, light, and soft:
+more removed, blacke and ponderous: the uttermost brow, that declineth
+like the seates in a theater, flourishing with trees and excellent
+pasturage. The midst of the hill is shaded with chestnut trees, and
+others bearing sundry fruits."[116]
+
+I am convinced that forests would soon cover many parts of the Arabian
+and African deserts, if man and domestic animals, especially the goat
+and the camel, were banished from them. The hard palate and tongue and
+strong teeth and jaws of this latter quadruped enable him to break off
+and masticate tough and thorny branches as large as the finger. He is
+particularly fond of the smaller twigs, leaves, and seedpods of the
+_sont_ and other acacias, which, like the American Robinia, thrive well
+on dry and sandy soils, and he spares no tree the branches of which are
+within his reach, except, if I remember right, the tamarisk that
+produces manna. Young trees sprout plentifully around the springs and
+along the winter watercourses of the desert, and these are just the
+halting stations of the caravans and their routes of travel. In the
+shade of these trees, annual grasses and perennial shrubs shoot up, but
+are mown down by the hungry cattle of the Bedouin, as fast as they grow.
+A few years of undisturbed vegetation would suffice to cover such points
+with groves, and these would gradually extend themselves over soils
+where now scarcely any green thing but the bitter colocynth and the
+poisonous foxglove is ever seen.
+
+
+_The Forest does not Furnish Food for Man._
+
+In a region absolutely covered with trees, human life could not long be
+sustained, for want of animal and vegetable food. The depths of the
+forest seldom furnish either bulb or fruit suited to the nourishment of
+man; and the fowls and beasts on which he feeds are scarcely seen except
+upon the margin of the wood, for here only grow the shrubs and grasses,
+and here only are found the seeds and insects, which form the sustenance
+of the non-carnivorous birds and quadrupeds.[117]
+
+
+_First Removal of the Forest._
+
+As soon as multiplying man had filled the open grounds along the margin
+of the rivers, the lakes, and the sea, and sufficiently peopled the
+natural meadows and savannas of the interior, where such existed,[118]
+he could find room for expansion and further growth, only by the
+removal of a portion of the forest that hemmed him in. The destruction
+of the woods, then, was man's first geographical conquest, his first
+violation of the harmonies of inanimate nature.
+
+Primitive man had little occasion to fell trees for fuel, or, for the
+construction of dwellings, boats, and the implements of his rude
+agriculture and handicrafts. Windfalls would furnish a thin population
+with a sufficient supply of such material, and if occasionally a growing
+tree was cut, the injury to the forest would be too insignificant to be
+at all appreciable.
+
+The accidental escape and spread of fire, or, possibly, the combustion
+of forests by lightning, must have first suggested the advantages to be
+derived from the removal of too abundant and extensive woods, and, at
+the same time, have pointed out a means by which a large tract of
+surface could readily be cleared of much of this natural incumbrance. As
+soon as agriculture had commenced at all, it would be observed that the
+growth of cultivated plants, as well as of many species of wild
+vegetation, was particularly rapid and luxuriant on soils which had been
+burned over, and thus a new stimulus would be given to the practice of
+destroying the woods by fire, as a means of both extending the open
+grounds, and making the acquisition of a yet more productive soil. After
+a few harvests had exhausted the first rank fertility of the virgin
+mould, or when weeds and briers and the sprouting roots of the trees had
+begun to choke the crops of the half-subdued soil, the ground would be
+abandoned for new fields won from the forest by the same means, and the
+deserted plain or hillock would soon clothe itself anew with shrubs and
+trees, to be again subjected to the same destructive process, and again
+surrendered to the restorative powers of vegetable nature.[119] This
+rude economy would be continued for generations, and wasteful as it is,
+is still largely pursued in Northern Sweden, Swedish Lapland, and
+sometimes even in France and the United States.[120]
+
+
+_Effects of Fire on Forest Soil._
+
+Aside from the mechanical and chemical effects of the disturbance of the
+soil by agricultural operations, and of the freer admission of sun,
+rain, and air to the ground, the fire of itself exerts an important
+influence on its texture and condition. It consumes a portion of the
+half-decayed vegetable mould which served to hold its mineral particles
+together and to retain the water of precipitation, and thus loosens,
+pulverizes, and dries the earth; it destroys reptiles, insects, and
+worms, with their eggs, and the seeds of trees and of smaller plants; it
+supplies, in the ashes which it deposits on the surface, important
+elements for the growth of a new forest clothing, as well as of the
+usual objects of agricultural industry; and by the changes thus
+produced, it fits the ground for the reception of a vegetation different
+in character from that which had spontaneously covered it. These new
+conditions help to explain the natural succession of forest crops, so
+generally observed in all woods cleared by fire and then abandoned.
+There is no doubt, however, that other influences contribute to the same
+result, because effects more or less analogous follow when the trees are
+destroyed by other causes, as by high winds, by the woodman's axe, and
+even by natural decay.[121]
+
+
+_Effects of Destruction of the Forest._
+
+The physico-geographical effects of the destruction of the forests may
+be divided into two great classes, each having an important influence on
+vegetable and on animal life in all their manifestations, as well as on
+every branch of rural economy and productive industry, and, therefore,
+on all the material interests of man. The first respects the meteorology
+of the countries exposed to the action of these influences; the second,
+their superficial geography, or, in other words, configuration,
+consistence, and clothing of surface.
+
+For reasons assigned in the first chapter, the meteorological or
+climatic branch of the subject is the most obscure, and the conclusions
+of physicists respecting it are, in a great degree, inferential only,
+not founded on experiment or direct observation. They are, as might be
+expected, somewhat discordant, though certain general results are almost
+universally accepted, and seem indeed too well supported to admit of
+serious question.
+
+
+_Electrical Influence of Trees._
+
+The properties of trees, singly and in groups, as exciters or conductors
+of electricity, and their consequent influence upon the electrical state
+of the atmosphere, do not appear to have been much investigated; and the
+conditions of the forest itself are so variable and so complicated, that
+the solution of any general problem respecting its electrical influence
+would be a matter of extreme difficulty. It is, indeed, impossible to
+suppose that a dense cloud, a sea of vapor, can pass over miles of
+surface bristling with good conductors, without undergoing some change
+of electrical condition. Hypothetical cases may be put in which the
+character of the change could be deduced from the known laws of
+electrical action. But in actual nature, the elements are too numerous
+for us to seize. The true electrical condition of neither cloud nor
+forest could be known, and it could seldom be predicted whether the
+vapors would be dissolved as they floated over the wood, or discharged
+upon it in a deluge of rain. With regard to possible electrical
+influences of the forest, wider still in their range of action, the
+uncertainty is even greater. The data which alone could lead to certain,
+or even probable, conclusions are wanting, and we should, therefore,
+only embarrass our argument by any attempt to discuss this
+meteorological element, important as it may be, in its relations of
+cause and effect to more familiar and better understood meteoric
+phenomena. It may, however, be observed that hail storms--which were
+once generally supposed, and are still held by many, to be produced by a
+specific electrical action, and which, at least, are always accompanied
+by electrical disturbances--are believed, in all countries particularly
+exposed to that scourge, to have become more frequent and destructive in
+proportion as the forests have been cleared. Caimi observes: "When the
+chains of the Alps and the Apennines had not yet been stripped of their
+magnificent crown of woods, the May hail, which now desolates the
+fertile plains of Lombardy, was much less frequent; but since the
+general prostration of the forest, these tempests are laying waste even
+the mountain soils whose older inhabitants scarcely knew this
+plague.[122] The _paragrandini_,[123] which the learned curate of
+Rivolta advised to erect, with sheaves of straw set up vertically, over
+a great extent of cultivated country, are but a Liliputian image of the
+vast paragrandini, pines, larches, firs, which nature had planted by
+millions on the crests and ridges of the Alps and the Apennines."[124]
+"Electrical action being diminished," says Meguscher, "and the rapid
+congelation of vapors by the abstraction of heat being impeded by the
+influence of the woods, it is rare that hail or waterspouts are
+produced, within the precincts of a large forest when it is assailed by
+the tempest."[125] Arthur Young was told that since the forests which
+covered the mountains between the Riviera and the county of Montferrat
+had disappeared, hail had become more destructive in the district of
+Acqui,[126] and it appears upon good authority, that a similar increase
+in the frequency and violence of hail storms in the neighborhood of
+Saluzzo and Mondovi, the lower part of the Valtelline, and the territory
+of Verona and Vicenza, is probably to be ascribed to a similar
+cause.[127]
+
+
+_Chemical Influence of the Forest._
+
+We know that the air in a close apartment is appreciably affected
+through the inspiration and expiration of gases by plants growing in it.
+The same operations are performed on a gigantic scale by the forest, and
+it has even been supposed that the absorption of carbon, by the rank
+vegetation of earlier geological periods, occasioned a permanent change
+in the constitution of the terrestrial atmosphere.[128] To the effects
+thus produced, are to be added those of the ultimate gaseous
+decomposition of the vast vegetable mass annually shed by trees, and of
+their trunks and branches when they fall a prey to time. But the
+quantity of gases thus abstracted from and restored to the atmosphere is
+inconsiderable--infinitesimal, one might almost say--in comparison with
+the ocean of air from which they are drawn and to which they return; and
+though the exhalations from bogs, and other low grounds covered with
+decaying vegetable matter, are highly deleterious to human health, yet,
+in general, the air of the forest is hardly chemically distinguishable
+from that of the sand plains, and we can as little trace the influence
+of the woods in the analysis of the atmosphere, as we can prove that the
+mineral ingredients of land springs sensibly affect the chemistry of
+the sea. I may, then, properly dismiss the chemical, as I have done the
+electrical influences of the forest, and treat them both alike, if not
+as unimportant agencies, at least as quantities of unknown value in our
+meteorological equation.[129] Our inquiries upon this branch of the
+subject will accordingly be limited to the thermometrical and
+hygrometrical influences of the woods.
+
+
+_Influence of the Forest, considered as Inorganic Matter, on
+Temperature._
+
+The evaporation of fluids, and the condensation and expansion of vapors
+and gases, are attended with changes of temperature; and the quantity of
+moisture which the air is capable of containing, and, of course, the
+evaporation, rise and fall with the thermometer. The hygroscopical and
+the thermoscopical conditions of the atmosphere are, therefore,
+inseparably connected as reciprocally dependent quantities, and neither
+can be fully discussed without taking notice of the other. But the
+forest, regarded purely as inorganic matter, and without reference to
+its living processes of absorption and exhalation of water and gases,
+has, as an absorbent, a radiator and a conductor of heat, and as a mere
+covering of the ground, an influence on the temperature of the air and
+the earth, which may be considered by itself.
+
+
+a. _Absorbing and Emitting Surface._
+
+A given area of ground, as estimated by the every-day rule of
+measurement in yards or acres, presents always the same apparent
+quantity of absorbing, radiating, and reflecting surface; but the real
+extent of that surface is very variable, depending, as it does, upon its
+configuration, and the bulk and form of the adventitious objects it
+bears upon it; and, besides, the true superficies remaining the same,
+its power of absorption, radiation, reflection, and conduction of heat
+will be much affected by its consistence, its greater or less humidity,
+and its color, as well as by its inclination of plane and
+exposure.[130] An acre of chalk, rolled hard and smooth, would have
+great reflecting power, but its radiation would be much increased by
+breaking it up into clods, because the actually exposed surface would be
+greater, though the outline of the field remained the same. The area of
+a triangle being equal to its base multiplied by half the length of a
+perpendicular let fall from its apex, it follows that the entire
+superficies of the triangular faces of a quadrangular pyramid, the
+perpendicular of whose sides should be twice the length of the base,
+would be four times the area of the ground it covered, and would add to
+the field on which it stood so much surface capable of receiving and
+emitting heat, though, in consequence of obliquity and direction of
+plane, its actual absorption and emission of heat might not be so great
+as that of an additional quantity of level ground containing four times
+the area of its base. The lesser inequalities which always occur in the
+surface of ordinary earth affect in the same way its quantity of
+superficies acting upon the temperature of the atmosphere, and acted on
+by it, though the amount of this action and reaction is not susceptible
+of measurement.
+
+Analogous effects are produced by other objects, of whatever form or
+character, standing or lying upon the earth, and no solid can be placed
+upon a flat piece of ground, without itself exposing a greater surface
+than it covers. This applies, of course, to forest trees and their
+leaves, and indeed to all vegetables, as well as to other prominent
+bodies. If we suppose forty trees to be planted on an acre, one being
+situated in the centre of every square of two rods the side, and to grow
+until their branches and leaves everywhere meet, it is evident that,
+when in full foliage, the trunks, branches, and leaves would present an
+amount of thermoscopic surface much greater than that of an acre of bare
+earth; and besides this, the fallen leaves lying scattered on the
+ground, would somewhat augment the sum total.[131] On the other hand,
+the growing leaves of trees generally form a succession of stages, or,
+loosely speaking, layers, corresponding to the animal growth of the
+branches, and more or less overlying each other. This disposition of the
+foliage interferes with that free communication between sun and sky
+above, and leaf surface below, on which the amount of radiation and
+absorption of heat depends. From all these considerations, it appears
+that though the effective thermoscopic surface of a forest in full leaf
+does not exceed that of bare ground in the same proportion as does its
+measured superficies, yet the actual quantity of area capable of
+receiving and emitting heat must be greater in the former than in the
+latter case.[132]
+
+It must further be remembered that the form and texture of a given
+surface are important elements in determining its thermoscopic
+character. Leaves are porous, and admit air and light more or less
+freely into their substance; they are generally smooth and even glazed
+on one surface; they are usually covered on one or both sides with
+spiculae, and they very commonly present one or more acuminated points in
+their outline--all circumstances which tend to augment their power of
+emitting heat by reflection or radiation. Direct experiment on growing
+trees is very difficult, nor is it in any case practicable to
+distinguish how far a reduction of temperature produced by vegetation is
+due to radiation, and how far to exhalation of the fluids of the plant
+in a gaseous form; for both processes usually go on together. But the
+frigorific effect of leafy structure is well observed in the deposit of
+dew and the occurrence of hoarfrost on the foliage of grasses and other
+small vegetables, and on other objects of similar form and consistence,
+when the temperature of the air a few yards above has not been brought
+down to the dew point, still less to 32 deg., the degree of cold required to
+congeal dew to frost.[133]
+
+
+b. _Trees as Conductors of Heat._
+
+We are also to take into account the action of the forest as a conductor
+of heat between the atmosphere and the earth. In the most important
+countries of America and Europe, and especially in those which have
+suffered most from the destruction of the woods, the superficial strata
+of the earth are colder in winter, and warmer in summer than those a few
+inches lower, and their shifting temperature approximates to the
+atmospheric mean of the respective seasons. The roots of large trees
+penetrate beneath the superficial strata, and reach earth of a nearly
+constant temperature, corresponding to the mean for the entire year. As
+conductors, they convey the heat of the atmosphere to the earth when the
+earth is colder than the air, and transmit it in the contrary direction
+when the temperature of the earth is higher than that of the atmosphere.
+Of course, then, as conductors, they tend to equalize the temperature of
+the earth and the air.
+
+
+c. _Trees in Summer and Winter._
+
+In countries where the questions I am considering have the greatest
+practical importance, a very large proportion, if not a majority, of the
+trees are of deciduous foliage, and their radiating as well as their
+shading surface is very much greater in summer than in winter. In the
+latter season, they little obstruct the reception of heat by the ground
+or the radiation from it; whereas, in the former, they often interpose a
+complete canopy between the ground and the sky, and materially
+interfere with both processes.
+
+
+d. _Dead Products of Trees._
+
+Besides this various action of standing trees considered as inorganic
+matter, the forest exercises, by the annual moulting of its foliage,
+still another influence on the temperature of the earth, and,
+consequently, of the atmosphere which rests upon it. If you examine the
+constitution of the superficial soil in a primitive or an old and
+undisturbed artificially planted wood, you find, first, a deposit of
+undecayed leaves, twigs, and seeds, lying in loose layers on the
+surface; then, more compact beds of the same materials in incipient,
+and, as you descend, more and more advanced stages of decomposition;
+then, a mass of black mould, in which traces of organic structure are
+hardly discoverable except by microscopic examination; then, a stratum
+of mineral soil, more or less mixed with vegetable matter carried down
+into it by water, or resulting from the decay of roots; and, finally,
+the inorganic earth or rock itself. Without this deposit of the dead
+products of trees, this latter would be the superficial stratum, and as
+its powers of absorption, radiation, and conduction of heat would differ
+essentially from those of the layers with which it has been covered by
+the droppings of the forest, it would act upon the temperature of the
+atmosphere, and be acted on by it, in a very different way from the
+leaves and mould which rest upon it. Leaves, still entire, or partially
+decayed, are very indifferent conductors of heat, and, therefore, though
+they diminish the warming influence of the summer sun on the soil below
+them, they, on the other hand, prevent the escape of heat from that soil
+in winter, and, consequently, in cold climates, even when the ground is
+not covered by a protecting mantle of snow, the earth does not freeze to
+as great a depth in the wood as in the open field.
+
+
+e. _Trees as a Shelter to Ground to the Leeward._
+
+The action of the forest, considered merely as a mechanical shelter to
+grounds lying to the leeward of it, would seem to be an influence of too
+restricted a character to deserve much notice; but many facts concur to
+show that it is an important element in local climate, and that it is
+often a valuable means of defence against the spread of miasmatic
+effluvia, though, in this last case, it may exercise a chemical as well
+as a mechanical agency. In the report of a committee appointed in 1836
+to examine an article of the forest code of France, Arago observes: "If
+a curtain of forest on the coasts of Normandy and of Brittany were
+destroyed, these two provinces would become accessible to the winds from
+the west, to the mild breezes of the sea. Hence a decrease of the cold
+of winter. If a similar forest were to be cleared on the eastern border
+of France, the glacial east wind would prevail with greater strength,
+and the winters would become more severe. Thus the removal of a belt of
+wood would produce opposite effects in the two regions."[134]
+
+This opinion receives confirmation from an observation of Dr. Dwight,
+who remarks, in reference to the woods of New England: "Another effect
+of removing the forest will be the free passage of the winds, and among
+them of the southern winds, over the surface. This, I think, has been an
+increasing fact within my own remembrance. As the cultivation of the
+country has extended farther to the north, the winds from the south have
+reached distances more remote from the ocean, and imparted their warmth
+frequently, and in such degrees as, forty years since, were in the same
+places very little known. This fact, also, contributes to lengthen the
+summer, and to shorten the winter-half of the year."[135]
+
+It is thought in Italy that the clearing of the Apennines has very
+materially affected the climate of the valley of the Po. It is asserted
+in Le Alpi che cingono l'Italia that: "In consequence of the felling of
+the woods on the Apennines, the sirocco prevails greatly on the right
+bank of the Po, in the Parmesan territory, and in a part of Lombardy; it
+injures the harvests and the vineyards, and sometimes ruins the crops of
+the season. To the same cause many ascribe the meteorological changes in
+the precincts of Modena and of Reggio. In the communes of these
+districts, where formerly straw roofs resisted the force of the winds,
+tiles are now hardly sufficient; in others, where tiles answered for
+roofs, large slabs of stone are now ineffectual; and in many neighboring
+communes the grapes and the grain are swept off by the blasts of the
+south and southwest winds."
+
+On the other hand, according to the same authority, the pinery of Porto,
+near Ravenna--which is 33 kilometres long, and is one of the oldest pine
+woods in Italy--having been replanted with resinous trees after it was
+unfortunately cut, has relieved the city from the sirocco to which it
+had become exposed, and in a great degree restored its ancient
+climate.[136]
+
+The felling of the woods on the Atlantic coast of Jutland has exposed
+the soil not only to drifting sands, but to sharp sea winds, that have
+exerted a sensible deteriorating effect on the climate of that
+peninsula, which has no mountains to serve at once as a barrier to the
+force of the winds, and as a storehouse of moisture received by
+precipitation or condensed from atmospheric vapors.[137]
+
+It is evident that the effect of the forest, as a mechanical impediment
+to the passage of the wind, would extend to a very considerable distance
+above its own height, and hence protect while standing, or lay open when
+felled, a much larger surface than might at first thought be supposed.
+The atmosphere, movable as are its particles, and light and elastic as
+are its masses, is nevertheless held together as a continuous whole by
+the gravitation of its atoms and their consequent pressure on each
+other, if not by attraction between them, and, therefore, an obstruction
+which mechanically impedes the movement of a given stratum of air, will
+retard the passage of the strata above and below it. To this effect may
+often be added that of an ascending current from the forest itself,
+which must always exist when the atmosphere within the wood is warmer
+than the stratum of air above it, and must be of almost constant
+occurrence in the case of cold winds, from whatever quarter, because the
+still air in the forest is slow in taking up the temperature of the
+moving columns and currents around and above it. Experience, in fact,
+has shown that mere rows of trees, and even much lower obstructions, are
+of essential service in defending vegetation against the action of the
+wind. Hardy proposes planting, in Algeria, belts of trees at the
+distance of one hundred metres from each other, as a shelter which
+experience had proved to be useful in France.[138] "In the valley of the
+Rhone," says Becquerel, "a simple hedge, two metres in height, is a
+sufficient protection for a distance of twenty-two metres."[139] The
+mechanical shelter acts, no doubt, chiefly as a defence against the
+mechanical force of the wind, but its uses are by no means limited to
+this effect. If the current of air which it resists moves horizontally,
+it would prevent the access of cold or parching blasts to the ground for
+a great distance; and did the wind even descend at a large angle with
+the surface, still a considerable extent of ground would be protected by
+a forest to the windward of it. If we suppose the trees of a wood to
+have a mean height of only twenty yards, they would often beneficially
+affect the temperature or the moisture of a belt of land two or three
+hundred yards in width, and thus perhaps rescue valuable crops from
+destruction.[140]
+
+The local retardation of spring so much complained of in Italy, France,
+and Switzerland, and the increased frequency of late frosts at that
+season, appear to be ascribable to the admission of cold blasts to the
+surface, by the felling of the forests which formerly both screened it
+as by a wall, and communicated the warmth of their soil to the air and
+earth to the leeward. Caimi states that since the cutting down of the
+woods of the Apennines, the cold winds destroy or stunt the vegetation,
+and that, in consequence of "the usurpation of winter on the domain of
+spring," the district of Mugello has lost all its mulberries, except the
+few which find in the lee of buildings a protection like that once
+furnished by the forest.[141]
+
+"It is proved," says Clave, "Etudes," p. 44, "that the department of
+Ardeche, which now contains not a single considerable wood, has
+experienced within thirty years a climatic disturbance, of which the
+late frosts, formerly unknown in the country, are one of the most
+melancholy effects. Similar results have been observed in the plain of
+Alsace, in consequence of the denudation of several of the crests of the
+Vosges."
+
+Dussard, as quoted by Ribbe,[142] maintains that even the _mistral_, or
+northwest wind, whose chilling blasts are so fatal to tender vegetation
+in the spring, "is the child of man, the result of his devastations."
+"Under the reign of Augustus," continues he, "the forests which
+protected the Cevennes were felled, or destroyed by fire, in mass. A
+vast country, before covered with impenetrable woods--powerful obstacles
+to the movement and even to the formation of hurricanes--was suddenly
+denuded, swept bare, stripped, and soon after, a scourge hitherto
+unknown struck terror over the land from Avignon to the Bouches du
+Rhone, thence to Marseilles, and then extended its ravages, diminished
+indeed by a long career which had partially exhausted its force, over
+the whole maritime frontier. The people thought this wind a curse sent
+of God. They raised altars to it and offered sacrifices to appease its
+rage." It seems, however, that this plague was less destructive than at
+present, until the close of the sixteenth century, when further
+clearings had removed most of the remaining barriers to its course. Up
+to that time, the northwest wind appears not to have attained to the
+maximum of specific effect which now characterizes it as a local
+phenomenon. Extensive districts, from which the rigor of the seasons has
+now banished valuable crops, were not then exposed to the loss of their
+harvests by tempests, cold, or drought. The deterioration was rapid in
+its progress. Under the Consulate, the clearings had exerted so
+injurious an effect upon the climate, that the cultivation of the olive
+had retreated several leagues, and since the winters and springs of 1820
+and 1836, this branch of rural industry has been abandoned in a great
+number of localities where it was advantageously pursued before. The
+orange now flourishes only at a few sheltered points of the coast, and
+it is threatened even at Ilyeres, where the clearing of the hills near
+the town has proved very prejudicial to this valuable tree.
+
+Marchand informs us that, since the felling of the woods, late spring
+frosts are more frequent in many localities north of the Alps; that
+fruit trees thrive well no longer, and that it is difficult to raise
+young trees.[143]
+
+
+f. _Trees as a Protection against Malaria._
+
+The influence of forests in preventing the diffusion of miasmatic vapors
+is a matter of less familiar observation, and perhaps does not come
+strictly within the sphere of the present inquiry, but its importance
+will justify me in devoting some space to the subject. "It has been
+observed" (I quote again from Becquerel) "that humid air, charged with
+miasmata, is deprived of them in passing through the forest. Rigaud de
+Lille observed localities in Italy where the interposition of a screen
+of trees preserved everything beyond it, while the unprotected grounds
+were subject to fevers."[144] Few European countries present better
+opportunities for observation on this point than Italy, because in that
+kingdom the localities exposed to miasmatic exhalations are numerous,
+and belts of trees, if not forests, are of so frequent occurrence that
+their efficacy in this respect can be easily tested. The belief that
+rows of trees afford an important protection against malarious
+influences is very general among Italians best qualified by intelligence
+and professional experience to judge upon the subject. The commissioners
+appointed to report on the measures to be adopted for the improvement of
+the Tuscan Maremme advised the planting of three or four rows of
+poplars, _Populus alba_, in such directions as to obstruct the currents
+of air from malarious localities, and thus intercept a great proportion
+of the pernicious exhalations."[145] Lieutenant Maury even believed that
+a few rows of sunflowers, planted between the Washington Observatory and
+the marshy banks of the Potomac, had saved the inmates of that
+establishment from the intermittent fevers to which they had been
+formerly liable. Maury's experiments have been repeated in Italy. Large
+plantations of sunflowers have been made upon the alluvial deposits of
+the Oglio, above its entrance into the Lake of Iseo near Pisogne, and it
+is said with favorable results to the health of the neighborhood.[146]
+In fact, the generally beneficial effects of a forest wall or other
+vegetable screen, as a protection against noxious exhalations from
+marshes or other sources of disease situated to the windward of them,
+are very commonly admitted.
+
+It is argued that, in these cases, the foliage of trees and of other
+vegetables exercises a chemical as well as a mechanical effect upon the
+atmosphere, and some, who allow that forests may intercept the
+circulation of the miasmatic effluvia of swampy soils, or even render
+them harmless by decomposing them, contend, nevertheless, that they are
+themselves active causes of the production of malaria. The subject has
+been a good deal discussed in Italy, and there is some reason to think
+that under special circumstances the influence of the forest in this
+respect may be prejudicial rather than salutary, though this does not
+appear to be generally the case.[147] It is, at all events, well known
+that the great swamps of Virginia and the Carolinas, in climates nearly
+similar to that of Italy, are healthy even to the white man, so long as
+the forests in and around them remain, but become very insalubrious when
+the woods are felled.[148]
+
+
+_The Forest, as Inorganic Matter, tends to mitigate Extremes._
+
+The surface which trees and leaves present augments the general
+superficies of the earth exposed to the absorption of heat, and
+increases the radiating and reflecting area in the same proportion. It
+is impossible to measure the relative value of these two
+elements--increase of absorbing and increase of emitting surface--as
+thermometrical influences, because they exert themselves under
+infinitely varied conditions; and it is equally impossible to make a
+quantitative estimate of any partial, still more of the total effect of
+the forest, considered as dead matter, on the temperature of the
+atmosphere, and of the portion of the earth's surface acted on by it.
+But it seems probable that its greatest influence in this respect is due
+to its character of a screen, or mechanical obstacle to the transmission
+of heat between the earth and the air; and this is equally true of the
+standing tree and of the dead foliage which it deposits in successive
+layers at its foot.
+
+The complicated action of trees and their products, as dead absorbents,
+radiators, reflectors, and conductors of heat, and as interceptors of
+its transmission, is so intimately connected with their effects upon the
+humidity of the air and the earth, and with all their living processes,
+that it is difficult to separate the former from the latter class of
+influences; but upon the whole, the forest must thus far be regarded as
+tending to mitigate extremes, and, therefore, as an equalizer of
+temperature.
+
+
+TREES AS ORGANISMS.
+
+_Specific Heat._
+
+Trees, considered as organisms, produce in themselves, or in the air, a
+certain amount of heat, by absorbing and condensing atmospheric vapor,
+and they exert an opposite influence by absorbing water and exhaling it
+in the form of vapor; but there is still another mode by which their
+living processes may warm the air around them, independently of the
+thermometric effects of condensation and evaporation. The vital heat of
+a dozen persons raises the temperature of a room. If trees possess a
+specific temperature of their own, an organic power of generating heat,
+like that with which the warm-blooded animals are gifted, though by a
+different process, a certain amount of weight is to be ascribed to this
+element, in estimating the action of the forest upon atmospheric
+temperature.
+
+"Observation shows," says Meguscher, "that the wood of a living tree
+maintains a temperature of +12 deg. or 13 deg. Cent. [= 54 deg., 56 deg. Fahr.] when the
+temperature of the air stands at 3 deg., 7 deg., and 8 deg. [=37 deg., 46 deg., 47 deg. F.]
+above zero, and that the internal warmth of the tree does not rise and
+fall in proportion to that of the atmosphere. So long as the latter is
+below 18 deg. [= 67 deg. Fahr.], that of the tree is always the highest; but if
+the temperature of the air rises to 18 deg., that of the vegetable growth is
+the lowest. Since, then, trees maintain at all seasons a constant mean
+temperature of 12 deg. [= 54 deg. Fahr.], it is easy to see why the air in
+contact with the forest must be warmer in winter, cooler in summer, than
+in situations where it is deprived of that influence."[149]
+
+Boussingault remarks: "In many flowers there has been observed a very
+considerable evolution of heat, at the approach of fecundation. In
+certain _arums_ the temperature rises to 40 deg. or 50 deg. Cent. [= 104 deg. or
+122 deg. Fahr.]. It is very probable that this phenomenon is general, and
+varies only in the intensity with which it is manifested."[150]
+
+If we suppose the fecundation of the flowers of forest trees to be
+attended with a tenth only of this calorific power, they could not fail
+to exert an important influence on the warmth of the atmospheric strata
+in contact with them.
+
+In a paper on Meteorology by Professor Henry, published in the United
+States Patent Office Report for 1857, p. 504, that distinguished
+physicist observes: "As a general deduction from chemical and mechanical
+principles, we think no change of temperature is ever produced where the
+actions belonging to one or both of these principles are not present.
+Hence, in midwinter, when all vegetable functions are dormant, we do not
+believe that any heat is developed by a tree, or that its interior
+differs in temperature from its exterior further than it is protected
+from the external air. The experiments which have been made on this
+point, we think, have been directed by a false analogy. During the
+active circulation of the sap and the production of new tissue,
+variations of temperature belonging exclusively to the plant may be
+observed; but it is inconsistent with general principles that heat
+should be generated where no change is taking place."
+
+There can be no doubt that moisture is given out by trees and evaporated
+in extremely cold winter-weather, and unless new fluid were supplied
+from the roots, the tree would be exhausted of its juices before winter
+was over. But this is not observed to be the fact, and, though the point
+is disputed, respectable authorities declare that "wood felled in the
+depth of winter is the heaviest and fullest of sap."[151] Warm weather
+in winter, of too short continuance to affect the temperature of the
+ground sensibly, stimulates a free flow of sap in the maple. Thus, in
+the last week of December, 1862, and the first week of January, 1863,
+sugar was made from that tree, in various parts of New England. "A
+single branch of a tree, admitted into a warm room in winter through an
+aperture in a window, opened its buds and developed its leaves while the
+rest of the tree in the external air remained in its winter sleep."[152]
+The roots of forest trees in temperate climates, remain, for the most
+part, in a moist soil, of a temperature not much below the annual mean,
+through the whole winter; and we cannot account for the uninterrupted
+moisture of the tree, unless we suppose that the roots furnish a
+constant supply of water.
+
+Atkinson describes a ravine in a valley in Siberia, which was filled
+with ice to the depth of twenty-five feet. Poplars were growing in this
+ice, which was thawed to the distance of some inches from the stem. But
+the surface of the soil beneath it must have remained still frozen, for
+the holes around the trees were full of water resulting from its
+melting, and this would have escaped below if the ground had been
+thawed. In this case, although the roots had not thawed the thick
+covering of earth above them, the trunks must have melted the ice in
+contact with them. The trees, when observed by Atkinson, were in full
+leaf, but it does not appear at what period the ice around their stems
+had melted.
+
+From these facts, and others of the like sort, it would seem that "all
+vegetable functions are" not absolutely "dormant" in winter, and,
+therefore, that trees may give out _some_ heat at that season. But,
+however this may be, the "circulation of the sap" commences at a very
+early period in the spring, and the temperature of the air in contact
+with trees may then be sufficiently affected by heat evolved in the
+vital processes of vegetation, to raise the thermometric mean of wooded
+countries for that season, and, of course, for the year.[153]
+
+
+_Total Influence of the Forest on Temperature._
+
+It has not yet been found practicable to measure, sum up, and equate the
+total influence of the forest, its processes and its products, dead and
+living, upon temperature, and investigators differ much in their
+conclusions on this subject. It seems probable that in every particular
+case the result is, if not determined, at least so much modified by
+local conditions which are infinitely varied, that no general formula is
+applicable to the question.
+
+In the report to which I referred on page 149, Gay-Lussac says: "In my
+opinion we have not yet any positive proof that the forest has, in
+itself, any real influence on the climate of a great country, or of a
+particular locality. By closely examining the effects of clearing off
+the woods, we should perhaps find that, far from being an evil, it is an
+advantage; but these questions are so complicated when they are examined
+in a climatological point of view, that the solution of them is very
+difficult, not to say impossible."
+
+Becquerel, on the other hand, considers it certain that in tropical
+climates, the destruction of the forests is accompanied with an
+elevation of the mean temperature, and he thinks it highly probable that
+it has the same effect in the temperate zones. The following is the
+substance of his remarks on this subject:--
+
+"Forests act as frigorific causes in three ways:
+
+"1. They shelter the ground against solar irradiation and maintain a
+greater humidity.
+
+"2. They produce a cutaneous transpiration by the leaves.
+
+"3. They multiply, by the expansion of their branches, the surfaces
+which are cooled by radiation.
+
+"These three causes acting with greater or less force, we must, in the
+study of the climatology of a country, take into account the proportion
+between the area of the forests and the surface which is bared of trees
+and covered with herbs and grasses.
+
+"We should be inclined to believe _a priori_, according to the foregoing
+considerations, that the clearing of the woods, by raising the
+temperature and increasing the dryness of the air, ought to react on
+climate. There is no doubt that, if the vast desert of the Sahara were
+to become wooded in the course of ages, the sands would cease to be
+heated as much as at the present epoch, when the mean temperature is
+twenty-nine degrees [centigrade, = 85 deg. Fahr.]. In that case, the
+ascending currents of warm air would cease, or be less warm, and would
+not contribute, by descending in our latitudes, to soften the climate of
+Western Europe. Thus the clearing of a great country may react on the
+climates of regions more or less remote from it.
+
+"The observations by Boussingault leave no doubt on this point. This
+writer determined the mean temperature of wooded and of cleared points,
+under the same latitude, and at the same elevation above the sea, in
+localities comprised between the eleventh degree of north and the fifth
+degree of south latitude, that is to say, in the portion of the tropics
+nearest to the equator, and where radiation tends powerfully during the
+night to lower the temperature under a sky without clouds."[154]
+
+The result of these observations, which has been pretty generally
+adopted by physicists, is that the mean temperature of cleared land in
+the tropics appears to be about one degree centigrade, or a little less
+than two degrees of Fahrenheit, above that of the forest. On page 147 of
+the volume just cited, Becquerel argues that, inasmuch as the same and
+sometimes a greater difference is found in favor of the open ground, at
+points within the tropics so elevated as to have a temperate or even a
+polar climate, we must conclude that the forests in Northern America
+exert a refrigerating influence equally powerful. But the conditions of
+the soil are so different in the two regions compared, that I think we
+cannot, with entire confidence, reason from the one to the other, and it
+is much to be desired that observations be made on the summer and winter
+temperature of both the air and the ground in the depths of the North
+American forests, before it is too late.[155]
+
+
+INFLUENCE OF FORESTS ON THE HUMIDITY OF THE AIR AND THE EARTH.
+
+
+a. _As Inorganic Matter._
+
+The most important influence of the forest on climate is, no doubt, that
+which it exercises on the humidity of the air and the earth, and this
+climatic action it exerts partly as dead, partly as living matter. By
+its interposition as a curtain between the sky and the ground, it
+intercepts a large proportion of the dew and the lighter showers, which
+would otherwise moisten the surface of the soil, and restores it to the
+atmosphere by evaporation; while in heavier rains, the large drops which
+fall upon the leaves and branches are broken into smaller ones, and
+consequently strike the ground with less mechanical force, or are
+perhaps even dispersed into vapor without reaching it.[156] As a screen,
+it prevents the access of the sun's rays to the earth, and, of course,
+an elevation of temperature which would occasion a great increase of
+evaporation. As a mechanical obstruction, it impedes the passage of air
+currents over the ground, which, as is well known, is one of the most
+efficient agents in promoting evaporation and the refrigeration
+resulting from it.[157] In the forest, the air is almost quiescent, and
+moves only as local changes of temperature affect the specific gravity
+of its particles. Hence there is often a dead calm in the woods when a
+furious blast is raging in the open country at a few yards' distance.
+The denser the forest--as for example, where it consists of spike-leaved
+trees, or is thickly intermixed with them--the more obvious is its
+effect, and no one can have passed from the field to the wood in cold,
+windy weather, without having remarked it.[158]
+
+The vegetable mould, resulting from the decomposition of leaves and of
+wood, carpets the ground with a spongy covering which obstructs the
+evaporation from the mineral earth below, drinks up the rains and
+melting snows that would otherwise flow rapidly over the surface and
+perhaps be conveyed to the distant sea, and then slowly gives out, by
+evaporation, infiltration, and percolation, the moisture thus imbibed.
+The roots, too, penetrate far below the superficial soil, conduct the
+water along their surface to the lower depths to which they reach, and
+thus serve to drain the superior strata and remove the moisture out of
+the reach of evaporation.
+
+
+b. _The Forest as Organic._
+
+These are the principal modes in which the humidity of the atmosphere is
+affected by the forest regarded as lifeless matter. Let us inquire how
+its organic processes act upon this meteorological element.
+
+The commonest observation shows that the wood and bark of living trees
+are always more or less pervaded with watery and other fluids, one of
+which, the sap, is very abundant in trees of deciduous foliage when the
+buds begin to swell and the leaves to develop themselves in the spring.
+The outer bark of most trees is of a corky character, not admitting the
+absorption of much moisture from the atmosphere through its pores, and
+we can hardly suppose that the buds are able to extract from the air a
+much larger supply. The obvious conclusion as to the source from which
+the extraordinary quantity of sap at this season is derived, is that to
+which scientific investigation leads us, namely, that it is absorbed
+from the earth by the roots, and thence distributed to all parts of the
+plant. Popular opinion, indeed, supposes that all the vegetable fluids,
+during the entire period of growth, are thus drawn from the bosom of the
+earth, and that the wood and other products of the tree are wholly
+formed from matter held in solution in the water abstracted by the roots
+from the ground. This is an error, for, not only is the solid matter of
+the tree, in a certain proportion not important to our present inquiry,
+received from the atmosphere in a gaseous form, through the pores of the
+leaves and of the young shoots, but water in the state of vapor is
+absorbed and contributed to the circulation, by the same organs.[159]
+The amount of water taken up by the roots, however, is vastly greater
+than that imbibed through the leaves, especially at the season when the
+juices are most abundant, and when, as we have seen, the leaves are yet
+in embryo. The quantity of water thus received from the air and the
+earth, in a single year, by a wood of even a hundred acres, is very
+great, though experiments are wanting to furnish the data for even an
+approximate estimate of its measure; for only the vaguest conclusions
+can be drawn from the observations which have been made on the
+imbibition and exhalation of water by trees and other plants reared in
+artificial conditions diverse from those of the natural forest.[160]
+
+
+_Wood Mosses and Fungi._
+
+Besides the water drawn by the roots from the earth and the vapor
+absorbed by the leaves from the air, the wood mosses and fungi, which
+abound in all dense forests, take up a great quantity of moisture from
+the atmosphere when it is charged with humidity, and exhale it again
+when the air is dry. These humble organizations, which play a more
+important part in regulating the humidity of the air than writers on the
+forest have usually assigned to them, perish with the trees they grow
+on; but, in many situations, nature provides a compensation for the tree
+mosses in ground species, which, on cold soils, especially those with a
+northern exposure, spring up abundantly both before the woods are
+felled, and when the land is cleared and employed for pasturage, or
+deserted. These mosses discharge a portion of the functions appropriated
+to the wood, and while they render the soil of improved lands much less
+fit for agricultural use, they, at the same time, prepare it for the
+growth of a new harvest of trees, when the infertility they produce
+shall have driven man to abandon it and suffer it to relapse into the
+hands of nature.[161]
+
+
+_Flow of Sap._
+
+The amount of sap which can be withdrawn from living trees furnishes,
+not indeed a measure of the quantity of water sucked up by their roots
+from the ground--for we cannot extract from a tree its whole
+moisture--but numerical data which may aid the imagination to form a
+general notion of the powerful action of the forest as an absorbent of
+humidity from the earth.
+
+The only forest tree known to Europe and North America, the sap of which
+is largely enough applied to economical uses to have made the amount of
+its flow a matter of practical importance and popular observation, is
+the sugar maple, _Acer saccharinum_, of the Anglo-American Provinces and
+States. In the course of a single "sugar season," which lasts ordinarily
+from twenty-five to thirty days, a sugar maple two feet in diameter will
+yield not less than twenty gallons of sap, and sometimes much more.[162]
+This, however, is but a trifling proportion of the water abstracted
+from the earth by the roots during this season, when the yet undeveloped
+leaves can hardly absorb an appreciable quantity of vapor from the
+atmosphere;[163] for all this fluid runs from two or three incisions or
+auger holes, so narrow as to intercept the current of comparatively few
+sap vessels, and besides, experience shows that large as is the quantity
+withdrawn from the circulation, it is relatively too small to affect
+very sensibly the growth of the tree.[164] The number of large maple
+trees on an acre is frequently not less than fifty,[165] and of course
+the quantity of moisture abstracted from the soil by this tree alone is
+measured by thousands of gallons to the acre. The sugar orchards, as
+they are called, contain also many young maples too small for tapping,
+and numerous other trees--two of which, at least, the black birch,
+_Betula lenta_, and yellow birch, _Betula excelsa_, both very common in
+the same climate, are far more abundant in sap than the maple[166]--are
+scattered among the sugar trees; for the North American native forests
+are remarkable for the mixture of their crops.
+
+The sap of the maple, and of other trees with deciduous leaves which
+grow in the same climate, flows most freely in the early spring, and
+especially in clear weather, when the nights are frosty and the days
+warm; for it is then that the melting snows supply the earth with
+moisture in the justest proportion, and that the absorbent power of the
+roots is stimulated to its highest activity.[167]
+
+When the buds are ready to burst, and the green leaves begin to show
+themselves beneath their scaly covering, the ground has become drier,
+the thirst of the roots is quenched, and the flow of sap from them to
+the stem is greatly diminished.[168]
+
+
+_Absorption and Exhalation of Moisture._
+
+The leaves now commence the process of absorption, and imbibe both
+uncombined gases and an unascertained but perhaps considerable quantity
+of watery vapor from the humid atmosphere of spring which bathes them.
+
+The organic action of the tree, as thus far described, tends to the
+desiccation of air and earth; but when we consider what volumes of water
+are daily absorbed by a large tree, and how small a proportion of the
+weight of this fluid consists of matter which enters into new
+combinations, and becomes a part of the solid framework of the
+vegetable, or a component of its deciduous products, it is evident that
+the superfluous moisture must somehow be carried off almost as rapidly
+as it flows into the tree.[169] At the very commencement of vegetation
+in spring, some of this fluid certainly escapes through the buds, the
+nascent foliage, and the pores of the barb, and vegetable physiology
+tells us that there is a current of sap toward the roots as well as from
+them.[170] I do not know that the exudation of water into the earth,
+through the bark or at the extremities of these latter organs, has been
+directly proved, but the other known modes of carrying off the surplus
+do not seem adequate to dispose of it at the almost leafless period when
+it is most abundantly received, and it is therefore difficult to believe
+that the roots do not, to some extent, drain as well as flood the
+watercourses of their stem. Later in the season the roots absorb less,
+and the now developed leaves exhale a vastly increased quantity of
+moisture into the air. In any event, all the water derived by the
+growing tree from the atmosphere and the ground is returned again by
+transpiration or exudation, after having surrendered to the plant the
+small proportion of matter required for vegetable growth which it held
+in solution or suspension.[171] The hygrometrical equilibrium is then
+restored, so far as this: the tree yields up again the moisture it had
+drawn from the earth and the air, though it does not return it each to
+each; for the vapor carried off by transpiration greatly exceeds the
+quantity of water absorbed by the foliage from the atmosphere, and the
+amount, if any, carried back to the ground by the roots.
+
+The evaporation of the juices of the plant, by whatever process
+effected, takes up atmospheric heat and produces refrigeration. This
+effect is not less real, though much less sensible, in the forest than
+in meadow or pasture land, and it cannot be doubted that the local
+temperature is considerably affected by it. But the evaporation that
+cools the air diffuses through it, at the same time, a medium which
+powerfully resists the escape of heat from the earth by radiation.
+Visible vapors or clouds, it is well known, prevent frosts by
+obstructing radiation, or rather by reflecting back again the heat
+radiated by the earth, just as any mechanical screen would do. On the
+other hand, clouds intercept the rays of the sun also, and hinder its
+heat from reaching the earth. The invisible vapors given out by leaves
+impede the passage of heat reflected and radiated by the earth and by
+all terrestrial objects, but oppose much less resistance to the
+transmission of direct solar heat, and indeed the beams of the sun seem
+more scorching when received through clear air charged with uncondensed
+moisture than after passing through a dry atmosphere. Hence the
+reduction of temperature by the evaporation of moisture from vegetation,
+though sensible, is less than it would be if water in the gaseous state
+were as impervious to heat given out by the sun as to that emitted by
+terrestrial objects.
+
+The hygroscopicity of vegetable mould is much greater than that of any
+mineral earth, and therefore the soil of the forest absorbs more
+atmospheric moisture than the open ground. The condensation of the vapor
+by absorption disengages heat, and consequently raises the temperature
+of the soil which absorbs it. Von Babo found the temperature of sandy
+earth thus elevated from 20 deg. to 27 deg. centigrade, making a difference of
+nearly thirteen degrees of Fahrenheit, and that of soil rich in humus
+from 20 deg. to 31 deg. centigrade, a difference of almost twenty degrees of
+Fahrenheit.[172]
+
+
+_Balance of Conflicting Influences._
+
+We have shown that the forest, considered as dead matter, tends to
+diminish the moisture of the air, by preventing the sun's rays from
+reaching the ground and evaporating the water that falls upon the
+surface, and also by spreading over the earth a spongy mantle which
+sucks up and retains the humidity it receives from the atmosphere,
+while, at the same time, this covering acts in the contrary direction by
+accumulating, in a reservoir not wholly inaccessible to vaporizing
+influences, the water of precipitation which might otherwise suddenly
+sink deep into the bowels of the earth, or flow by superficial channels
+to other climatic regions. We now see that, as a living organism, it
+tends, on the one hand, to diminish the humidity of the air by absorbing
+moisture from it, and, on the other, to increase that humidity by
+pouring out into the atmosphere, in a vaporous form, the water it draws
+up through its roots. This last operation, at the same time, lowers the
+temperature of the air in contact with or proximity to the wood, by the
+same law as in other cases of the conversion of water into vapor.
+
+As I have repeatedly said, we cannot measure the value of any one of
+these elements of climatic disturbance, raising or lowering of
+temperature, increase or diminution of humidity, nor can we say that in
+any one season, any one year, or any one fixed cycle, however long or
+short, they balance and compensate each other. They are sometimes, but
+certainly not always, contemporaneous in their action, whether their
+tendency is in the same or in opposite directions, and, therefore, their
+influence is sometimes cumulative, sometimes conflicting; but, upon the
+whole, their general effect seems to be to mitigate extremes of
+atmospheric heat and cold, moisture and drought. They serve as
+equalizers of temperature and humidity, and it is highly probable that,
+in analogy with most other works and workings of nature, they, at
+certain or uncertain periods, restore the equilibrium which, whether as
+lifeless masses or as living organisms, they may have temporarily
+disturbed.
+
+When, therefore, man destroyed these natural harmonizers of climatic
+discords, he sacrificed an important conservative power, though it is
+far from certain that he has thereby affected the mean, however much he
+may have exaggerated the extremes of atmospheric temperature and
+humidity, or, in other words, may have increased the range and
+lengthened the scale of thermometric and hygrometric variation.
+
+
+_Influence of the Forest on Temperature and Precipitation._
+
+Aside from the question of compensation, it does not seem probable that
+the forests sensibly affect the total quantity of precipitation, or the
+general mean of atmospheric temperature of the globe, or even that they
+had this influence when their extent was vastly greater than at present.
+The waters cover about three fourths of the face of the earth,[173] and
+if we deduct the frozen zones, the peaks and crests of lofty mountains
+and their craggy slopes, the Sahara and other great African and Asiatic
+deserts, and all such other portions of the solid surface as are
+permanently unfit for the growth of wood, we shall find that probably
+not one tenth of the total superficies of our planet was ever, at any
+one time in the present geological epoch, covered with forests. Besides
+this, the distribution of forest land, of desert, and of water, is such
+as to reduce the possible influence of the former to a low expression;
+for the forests are, in large proportion, situated in cold or temperate
+climates, where the action of the sun is comparatively feeble both in
+elevating temperature and in promoting evaporation; while, in the torrid
+zone, the desert and the sea--the latter of which always presents an
+evaporable surface--enormously preponderate. It is, upon the whole, not
+probable that so small an extent of forest, so situated, could produce
+an appreciable influence on the _general_ climate of the globe, though
+it might appreciably affect the local action of all climatic elements.
+The total annual amount of solar heat absorbed and radiated by the
+earth, and the sum of terrestrial evaporation and atmospheric
+precipitation must be supposed constant; but the distribution of heat
+and of humidity is exposed to disturbance in both time and place, by a
+multitude of local causes, among which the presence or absence of the
+forest is doubtless one.
+
+So far as we are able to sum up the general results, it would appear
+that, in countries in the temperate zone still chiefly covered with
+wood, the summers would be cooler, moister, shorter, the winters milder,
+drier, longer, than in the same regions after the removal of the forest.
+The slender historical evidence we possess seems to point to the same
+conclusion, though there is some conflict of testimony and of opinion on
+this point, and some apparently well-established exceptions to
+particular branches of what appears to be the general law.
+
+One of these occurs both in climates where the cold of winter is severe
+enough to freeze the ground to a considerable depth, as in Sweden and
+the Northern States of the American Union, and in milder zones, where
+the face of the earth is exposed to cold mountain winds, as in some
+parts of Italy and of France; for there, as we have seen, the winter is
+believed to extend itself into the months which belong to the spring,
+later than at periods when the forest covered the greater part of the
+ground.[174] More causes than one doubtless contribute to this result;
+but in the case of Sweden and the United States, the most obvious
+explanation of the fact is to be found in the loss of the shelter
+afforded to the ground by the thick coating of leaves which the forest
+sheds upon it, and the snow which the woods protect from blowing away,
+or from melting in the brief thaws of winter. I have already remarked
+that bare ground freezes much deeper than that which is covered by beds
+of leaves, and when the earth is thickly coated with snow, the strata
+frozen before it fell begin to thaw. It is not uncommon to find the
+ground in the woods, where the snow lies two or three feet deep,
+entirely free from frost, when the atmospheric temperature has been for
+several weeks below the freezing point, and for some days even below the
+zero of Fahrenheit. When the ground is cleared and brought under
+cultivation, the leaves are ploughed into the soil and decomposed, and
+the snow, especially upon knolls and eminences, is blown off, or
+perhaps half thawed, several times during the winter. The water from the
+melting snow runs into the depressions, and when, after a day or two of
+warm sunshine or tepid rain, the cold returns, it is consolidated to
+ice, and the bared ridges and swells of earth are deeply frozen.[175] It
+requires many days of mild weather to raise the temperature of soil in
+this condition, and of the air in contact with it, to that of the earth
+in the forests of the same climatic region. Flora is already plaiting
+her sylvan wreath before the corn flowers which are to deck the garland
+of Ceres have waked from their winter's sleep; and it is not a popular
+error to believe that, where man has substituted his artificial crops
+for the spontaneous harvest of nature, spring delays her coming.
+
+In many cases, the apparent change in the period of the seasons is a
+purely local phenomenon, which is probably compensated by a higher
+temperature in other months, without any real disturbance of the average
+thermometrical equilibrium. We may easily suppose that there are
+analogous partial deviations from the general law of precipitation; and,
+without insisting that the removal of the forest has diminished the sum
+total of snow and rain, we may well admit that it has lessened the
+quantity which annually falls within particular limits. Various
+theoretical considerations make this probable, the most obvious
+argument, perhaps, being that drawn from the generally admitted fact,
+that the summer and even the mean temperature of the forest is below
+that of the open country in the same latitude. If the air in a wood is
+cooler than that around it, it must reduce the temperature of the
+atmospheric stratum immediately above it, and, of course, whenever a
+saturated current sweeps over it, it must produce precipitation which
+would fall upon or near it.
+
+But the subject is so exceedingly complex and difficult, that it is
+safer to regard it as a historical problem, or at least as what lawyers
+call a mixed question of law and fact, than to attempt to decide it upon
+_a priori_ grounds. Unfortunately the evidence is conflicting in
+tendency, and sometimes equivocal in interpretation, but I believe that
+a majority of the foresters and physicists who have studied the question
+are of opinion that in many, if not in all cases, the destruction of the
+woods has been followed by a diminution in the annual quantity of rain
+and dew. Indeed, it has long been a popularly settled belief that
+vegetation and the condensation and fall of atmospheric moisture are
+reciprocally necessary to each other, and even the poets sing of
+
+ Afric's barren sand,
+ Where nought can grow, because it raineth not,
+ And where no rain can fall to bless the land,
+ Because nought grows there.[176]
+
+Before stating the evidence on the general question and citing the
+judgments of the learned upon it, however, it is well to remark that the
+comparative variety or frequency of inundations in earlier and later
+centuries is not necessarily, in most cases not probably, entitled to
+any weight whatever, as a proof that more or less rain fell formerly
+than now; because the accumulation of water in the channel of a river
+depends far less upon the quantity of precipitation in its valley, than
+upon the rapidity with which it is conducted, on or under the surface of
+the ground, to the central artery that drains the basin. But this point
+will be more fully discussed in a subsequent chapter.
+
+There is another important observation which may properly be introduced
+here. It is not universally, or even generally true, that the atmosphere
+returns its humidity to the local source from which it receives it. The
+air is constantly in motion,
+
+ ----howling tempests scour amain
+ From sea to land, from land to sea;[177]
+
+and, therefore, it is always probable that the evaporation drawn up by
+the atmosphere from a given river, or sea, or forest, or meadow, will be
+discharged by precipitation, not at or near the point where it rose, but
+at a distance of miles, leagues, or even degrees. The currents of the
+upper air are invisible, and they leave behind them no landmark to
+record their track. We know not whence they come, or whither they go. We
+have a certain rapidly increasing acquaintance with the laws of general
+atmospheric motion, but of the origin and limits, the beginning and end
+of that motion, as it manifests itself at any particular time and place,
+we know nothing. We cannot say where or when the vapor, exhaled to-day
+from the lake on which we float, will be condensed and fall; whether it
+will waste itself on a barren desert, refresh upland pastures, descend
+in snow on Alpine heights, or contribute to swell a distant torrent
+which shall lay waste square miles of fertile corn land; nor do we know
+whether the rain which feeds our brooklets is due to the transpiration
+from a neighboring forest, or to the evaporation from a far-off sea. If,
+therefore, it were proved that the annual quantity of rain and dew is
+now as great on the plains of Castile, for example, as it was when they
+were covered with the native forest, it would by no means follow that
+those woods did not augment the amount of precipitation elsewhere.
+
+But I return to the question. Beginning with the latest authorities, I
+cite a passage from Clave.[178] After arguing that we cannot reason from
+the climatic effects of the forest in tropical and sub-tropical
+countries as to its influence in temperate latitudes, the author
+proceeds: "The action of the forests on rain, a consequence of that
+which they exercise on temperature, is difficult to estimate in our
+climate, but is very pronounced in hot countries, and is established by
+numerous examples. M. Boussingault states that in the region comprised
+between the Bay of Cupica and the Gulf of Guayaquil, which is covered
+with immense forests, the rains are almost continual, and that the mean
+temperature of this humid country rises hardly to twenty-six degrees (=
+80 deg. Fahr.). M. Blanqui, in his 'Travels in Bulgaria,' informs us that at
+Malta rain has become so rare, since the woods were cleared to make room
+for the growth of cotton, that at the time of his visit in October,
+1841, not a drop of rain had fallen for three years.[179] The terrible
+droughts which desolate the Cape Verd Islands must also be attributed to
+the destruction of the forests. In the Island of St. Helena, where the
+wooded surface has considerably extended within a few years, it has been
+observed that the rain has increased in the same proportion. It is now
+in quantity double what it was during the residence of Napoleon. In
+Egypt, recent plantations have caused rains, which hitherto were almost
+unknown."
+
+Schacht[180] observes: "In wooded countries, the atmosphere is generally
+humid, and rain and dew fertilize the soil. As the lightning rod
+abstracts the electric fluid from the stormy sky, so the forest attracts
+to itself the rain from the clouds, which, in falling, refreshes not it
+alone, but extends its benefits to the neighboring fields. * * The
+forest, presenting a considerable surface for evaporation, gives to its
+own soil and to all the adjacent ground an abundant and enlivening dew.
+There falls, it is true, less dew on a tall and thick wood than on the
+surrounding meadows, which, being more highly heated during the day by
+the influence of insolation, cool with greater rapidity by radiation.
+But it must be remarked, that this increased deposition of dew on the
+neighboring fields is partly due to the forests themselves; for the
+dense, saturated strata of air which hover over the woods descend in
+cool, calm evenings, like clouds, to the valley, and in the morning,
+beads of dew sparkle on the leaves of the grass and the flowers of the
+field. Forests, in a word, exert, in the interior of continents, an
+influence like that of the sea on the climate of islands and of coasts:
+both water the soil and thereby insure its fertility." In a note upon
+this passage, quoting as authority the _Historia de la Conquista de las
+siete islas de Gran Canaria, de Juan de Abreu Galindo_, 1632, p. 47, he
+adds: "Old historians relate that a celebrated laurel in Ferro formerly
+furnished drinkable water to the inhabitants of the island. The water
+flowed from its foliage, uninterruptedly, drop by drop, and was
+collected in cisterns. Every morning the sea breeze drove a cloud toward
+the wonderful tree, which attracted it to its huge top," where it was
+condensed to a liquid form.
+
+In a number of the _Missionary Herald_, published at Boston, the date of
+which I have mislaid, the Rev. Mr. Van Lennep, well known as a competent
+observer, gives the following remarkable account of a similar fact
+witnessed by him in an excursion to the east of Tocat in Asia Minor:
+
+"In this region, some 3,000 feet above the sea, the trees are mostly
+oak, and attain a large size. I noticed an illustration of the influence
+of trees in general in collecting moisture. Despite the fog, of a week's
+duration, the ground was everywhere perfectly dry. The dry oak leaves,
+however, had gathered the water, and the branches and trunks of the
+trees were more or less wet. In many cases the water had run down the
+trunk and moistened the soil around the roots of the tree. In two
+places, several trees had each furnished a small stream of water, and
+these, uniting, had run upon the road, so that travellers had to pass
+through the mud; although, as I said, everywhere else the ground was
+perfectly dry. Moreover, the collected moisture was not sufficient to
+drop directly from the leaves, but in every case it ran down the
+branches and trunk to the ground. Farther on we found a grove, and at
+the foot of each tree, on the north side, was a lump of ice, the water
+having frozen as it reached the ground. This is a most striking
+illustration of the acknowledged influence of trees in collecting
+moisture; and one cannot for a moment doubt, that the parched regions
+which commence at Sivas, and extend in one direction to the Persian
+Gulf, and in another to the Red Sea, were once a fertile garden, teeming
+with a prosperous population, before the forests which covered the
+hillsides were cut down--before the cedar and the fir tree were rooted
+up from the sides of Lebanon.
+
+"As we now descended the northern side of the watershed, we passed
+through the grove of walnut, oak, and black mulberry trees, which shade
+the village of Oktab, whose houses, cattle, and ruddy children were
+indicative of prosperity."
+
+Coultas thus argues: "The ocean, winds, and woods may be regarded as the
+several parts of a grand distillatory apparatus. The sea is the boiler
+in which vapor is raised by the solar heat, the winds are the guiding
+tubes which carry the vapor with them to the forests where a lower
+temperature prevails. This naturally condenses the vapor, and showers of
+rain are thus distilled from the cloud masses which float in the
+atmosphere, by the woods beneath them."[181]
+
+Sir John F. W. Herschel enumerates among "the influences unfavorable to
+rain," "absence of vegetation in warm climates, and especially of trees.
+This is, no doubt," continues he, "one of the reasons of the extreme
+aridity of Spain. The hatred of a Spaniard toward a tree is proverbial.
+Many districts in France have been materially injured by denudation
+(Earl of Lovelace on Climate, etc.), and, on the other hand, rain has
+become more frequent in Egypt since the more vigorous cultivation of the
+palm tree."
+
+Hohenstein remarks: "With respect to the temperature in the forest, I
+have already observed that, at certain times of the day and of the year,
+it is less than in the open field. Hence the woods may, in the daytime,
+in summer and toward the end of winter, tend to increase the fall of
+rain; but it is otherwise in summer nights and at the beginning of
+winter, when there is a higher temperature in the forest, which is not
+favorable to that effect. * * * The wood is, further, like the mountain,
+a mechanical obstruction to the motion of rain clouds, and, as it checks
+them in their course, it gives them occasion to deposit their water.
+These considerations render it probable that the forest increases the
+quantity of rain; but they do not establish the certainty of this
+conclusion, because we have no positive numerical data to produce on the
+depression of temperature, and the humidity of the air in the
+woods."[182]
+
+Barth presents the following view of the subject: "The ground in the
+forest, as well as the atmospheric stratum over it, continues humid
+after the woodless districts have lost their moisture; and the air,
+charged with the humidity drawn from them, is usually carried away by
+the winds before it has deposited itself in a condensed form on the
+earth. Trees constantly transpire through their leaves a great quantity
+of moisture, which they partly absorb again by the same organs, while
+the greatest part of their supply is pumped up through their widely
+ramifying roots from considerable depths in the ground. Thus a constant
+evaporation is produced, which keeps the forest atmosphere moist even in
+long droughts, when all other sources of humidity in the forest itself
+are dried up. * * * Little is required to compel the stratum of air
+resting upon a wood to give up its moisture, which thus, as rain, fog,
+or dew, is returned to the forest. * * * The warm, moist currents of
+air which come from other regions are cooled as they approach the wood
+by its less heated atmosphere, and obliged to let fall the humidity with
+which they are charged. The woods contribute to the same effect by
+mechanically impeding the motion of fog and rain cloud, whose particles
+are thus accumulated and condensed to rain. The forest thus has a
+greater power than the open ground to retain within its own limits
+already existing humidity, and to preserve it, and it attracts and
+collects that which the wind brings it from elsewhere, and forces it to
+deposit itself as rain or other precipitation. * * * In consequence of
+these relations of the forest to humidity, it follows that wooded
+districts have both more frequent and more abundant rain, and in general
+are more humid, than woodless regions; for what is true of the woods
+themselves, in this respect, is true also of their treeless
+neighborhood, which, in consequence of the ready mobility of the air and
+its constant changes, receives a share of the characteristics of the
+forest atmosphere, coolness and moisture. * * * When the districts
+stripped of trees have long been deprived of rain and dew, * * * and the
+grass and the fruits of the field are ready to wither, the grounds which
+are surrounded by woods are green and flourishing. By night they are
+refreshed with dew, which is never wanting in the moist air of the
+forest, and in due season they are watered by a beneficent shower, or a
+mist which rolls slowly over them."[183]
+
+Asbjoernsen, after adducing the familiar theoretical arguments on this
+point, adds: "The rainless territories in Peru and North Africa
+establish this conclusion, and numerous other examples show that woods
+exert an influence in producing rain, and that rain fails where they are
+wanting; for many countries have, by the destruction of the forests,
+been deprived of rain, moisture, springs, and watercourses, which are
+necessary for vegetable growth. * * * The narratives of travellers show
+the deplorable consequences of felling the woods in the Island of
+Trinidad, Martinique, San Domingo, and indeed, in almost the entire
+West Indian group. * * * In Palestine and many other parts of Asia and
+Northern Africa, which in ancient times were the granaries of Europe,
+fertile and populous, similar consequences have been experienced. These
+lands are now deserts, and it is the destruction of the forests alone
+which has produced this desolation. * * * In Southern France, many
+districts have, from the same cause, become barren wastes of stone, and
+the cultivation of the vine and the olive has suffered severely since
+the baring of the neighboring mountains. Since the extensive clearings
+between the Spree and the Oder, the inhabitants complain that the clover
+crop is much less productive than before. On the other hand, examples of
+the beneficial influence of planting and restoring the woods are not
+wanting. In Scotland, where many miles square have been planted with
+trees, this effect has been manifest, and similar observations have been
+made in several places in Southern France. In Lower Egypt, both at Cairo
+and near Alexandria, rain rarely fell in considerable quantity--for
+example, during the French occupation of Egypt, about 1798, it did not
+rain for sixteen months--but since Mehemet Aali and Ibrahim Pacha
+executed their vast plantations (the former alone having planted more
+than twenty millions of olive and fig trees, cottonwood, oranges,
+acacias, planes, &c.), there now falls a good deal of rain, especially
+along the coast, in the months of November, December, and January; and
+even at Cairo it rains both oftener and more abundantly, so that real
+showers are no rarity."[184]
+
+Babinet, in one of his lectures,[185] cites the supposed fact of the
+increase of rain in Egypt in consequence of the planting of trees, and
+thus remarks upon it: "A few years ago it never rained in Lower Egypt.
+The constant north winds, which almost exclusively prevail there, passed
+without obstruction over a surface bare of vegetation. Grain was kept
+on the roofs in Alexandria, without being covered or otherwise
+protected from injury by the atmosphere; but since the making of
+plantations, an obstacle has been created which retards the current of
+air from the north. The air thus checked, accumulates, dilates, cools,
+and yields rain.[186] The forests of the Vosges and Ardennes produce
+the same effects in the north east of France, and send us a great river,
+the Meuse, which is as remarkable for its volume as for the small extent
+of its basin. With respect to the retardation of the atmospheric
+currents, and the effects of that retardation, one of my illustrious
+colleagues, M. Mignet, who is not less a profound thinker than an
+eloquent writer, suggested to me that, to produce rain, a forest was as
+good as a mountain, and this is literally true."
+
+Monestier-Savignat arrives at this conclusion: "Forests on the one hand
+diminish evaporation; on the other, they act on the atmosphere as
+refrigerating causes. The second scale of the balance predominates over
+the other, for it is established that in wooded countries it rains
+oftener, and that, the quantity of rain being equal, they are more
+humid."[187]
+
+Boussingault--whose observations on the drying up of lakes and springs,
+from the destruction of the woods, in tropical America, have often been
+cited as a conclusive proof that the quantity of rain was thereby
+diminished--after examining the question with much care, remarks: "In my
+judgment it is settled that very large clearings must diminish the
+annual fall of rain in a country;" and on a subsequent page, he
+concludes that, "arguing from meteorological facts collected in the
+equinoctial regions, there is reason to presume that clearings diminish
+the annual fall of rain."[188]
+
+The same eminent author proposes series of observations on the level of
+natural lakes, especially on those without outlet, as a means of
+determining the increase or diminution of precipitation in their basins,
+and, of course, of measuring the effect of clearing when such
+operations take place within those basins. But it must be observed that
+lakes without a visible outlet are of very rare occurrence, and besides,
+where no superficial conduit for the discharge of lacustrine waters
+exists, we can seldom or never be sure that nature has not provided
+subterranean channels for their escape. Indeed, when we consider that
+most earths, and even some rocks under great hydrostatic pressure, are
+freely permeable by water, and that fissures are frequent in almost all
+rocky strata, it is evident that we cannot know in what proportion the
+depression of the level of a lake is to be ascribed to infiltration, to
+percolation, or to evaporation.[189] Further, we are, in general, as
+little able to affirm that a given lake derives all its water from the
+fall of rain within its geographical basin, or that it receives all the
+water that falls in that basin except what evaporates from the ground,
+as we are to show that all its superfluous water is carried off by
+visible channels and by evaporation.
+
+Suppose the strata of the mountains on two sides of a lake, east and
+west, to be tilted in the same direction, and that those of the hill on
+the east side incline toward the lake, those of that on the west side
+from it. In this case a large proportion of the rain which falls on the
+eastern slope of the eastern hill may find its way between the strata to
+the lake, and an equally large proportion of the precipitation upon the
+eastern slope of the western ridge may escape out of the basin by
+similar channels. In such case the clearing of the _outer_ slopes of
+either or both mountains, while the forests of the _inner_ declivities
+remained intact, might affect the quantity of water received by the
+lake, and it would always be impossible to know to what territorial
+extent influences thus affecting the level of a lake might reach.
+Boussingault admits that extensive clearing _below_ an alpine lake, even
+at a considerable distance, might affect the level of its waters. How it
+would produce this influence he does not inform us, but, as he says
+nothing of the natural subterranean drainage of surface waters, it is to
+be presumed that he refers to the supposed diminution of the quantity of
+rain from the removal of the forest, which might manifest itself at a
+point more elevated than the cause which occasioned it. The elevation or
+depression of the level of natural lakes, then, cannot be relied upon as
+a proof, still less as a measure of an increase or diminution in the
+fall of rain within their geographical basins, resulting from the
+felling of the woods which covered them; though such phenomena afford
+very strong presumptive evidence that the supply of water is somehow
+augmented or lessened. The supply is, in most cases, derived much less
+from the precipitation which falls directly upon the surface of lakes,
+than from waters which flow above or under the ground around them, and
+which, in the latter case, often come from districts not comprised
+within what superficial geography would regard as belonging to the lake
+basins.
+
+It is, upon the whole, evident that the question can hardly be
+determined except by the comparison of pluviometrical observations made
+at a given station before and after the destruction of the woods. Such
+observations, unhappily, are scarcely to be found, and the opportunity
+for making them is rapidly passing away, except so far as a converse
+series might be collected in countries--France, for example--where
+forest plantation is now going on upon a large scale. The Smithsonian
+Institution at Washington is well situated for directing the attention
+of observers in the newer territory of the United States to this
+subject, and it is to be hoped that it will not fail to avail itself of
+its facilities for this purpose.
+
+Numerous other authorities might be cited in support of the proposition
+that forests tend, at least in certain latitudes and at certain seasons,
+to produce rain; but though the arguments of the advocates of this
+doctrine are very plausible, not to say convincing, their opinions are
+rather _a priori_ conclusions from general meteorological laws, than
+deductions from facts of observation, and it is remarkable that there is
+so little direct evidence on the subject.
+
+On the other hand, Foissac expresses the opinion that forests have no
+influence on precipitation, beyond that of promoting the deposit of dew
+in their vicinity, and he states, as a fact of experience, that the
+planting of large vegetables, and especially of trees, is a very
+efficient means of drying morasses, because the plants draw from the
+earth a quantity of water larger than the average annual fall of
+rain.[190] Kloeden, admitting that the rivers Oder and Elbe have
+diminished in quantity of water, the former since 1778, the latter since
+1828, denies that the diminution of volume is to be ascribed to a
+decrease of precipitation in consequence of the felling of the forests,
+and states, what other physicists confirm, that, during the same period,
+meteorological records in various parts of Europe show rather an
+augmentation than a reduction of rain.[191]
+
+The observations of Belgrand tend to show, contrary to the general
+opinion, that less rain falls in wooded than in denuded districts. He
+compared the precipitation for the year 1852, at Vezelay in the valley
+of the Bouchat, and at Avallon in the valley of the Grenetiere. At the
+first of these places it was 881 millimetres, at the latter 581
+millimetres. The two cities are not more than eight miles apart. They
+are at the same altitude, and it is stated that the only difference in
+their geographical conditions consists in the different proportions of
+forest and cultivated country around them, the basin of the Bouchat
+being entirely bare, while that of the Grenetiere is well wooded.[192]
+Observations in the same valleys, considered with reference to the
+seasons, show the following pluviometric results:
+
+FOR LA GRENETIERE.
+
+ February, 1852, 42.2 millimetres precipitation.
+ November, " 23.8 " "
+ January, 1853, 35.4 " "
+ -----
+ Total, 106.4 in three cold months.
+
+ September, 1851, 27.1 millimetres precipitation.
+ May, 1852, 20.9 " "
+ June, " 56.3 " "
+ July, " 22.8 " "
+ September, " 22.8 " "
+ -----
+ Total, 149.9 in five warm months.
+
+FOR LE BOUCHAT.
+
+ February, 1852, 51.3 millimetres precipitation.
+ November, " 36.6 " "
+ January, 1853, 92.0 " "
+ -----
+ Total, 179.9 in three cold months.
+
+ September, 1851, 43.8 millimetres precipitation.
+ May, 1852, 13.2 " "
+ June, " 55.5 " "
+ July, " 19.5 " "
+ September, " 26.5 " "
+ -----
+ Total, 158.5 in five warm months.
+
+These observations, so far as they go, seem to show that more rain falls
+in cleared than in wooded countries, but this result is so contrary to
+what has been generally accepted as a theoretical conclusion, that
+further experiment is required to determine the question.
+
+Becquerel--whose treatise on the climatic effects of the destruction of
+the forest is the fullest general discussion of that subject known to
+me--does not examine this particular point, and as, in the summary of
+the results of his investigations, he does not ascribe to the forest any
+influence upon precipitation, the presumption is that he rejects the
+doctrine of its importance as an agent in producing the fall of rain.
+
+The effect of the forest on precipitation, then, is not entirely free
+from doubt, and we cannot positively affirm that the total annual
+quantity of rain is diminished or increased by the destruction of the
+woods, though both theoretical considerations and the balance of
+testimony strongly favor the opinion that more rain falls in wooded than
+in open countries. One important conclusion, at least, upon the
+meteorological influence of forests is certain and undisputed: the
+proposition, namely, that, within their own limits, and near their own
+borders, they maintain a more uniform degree of humidity in the
+atmosphere than is observed in cleared grounds. Scarcely less can it be
+questioned that they promote the frequency of showers, and, if they do
+not augment the amount of precipitation, they equalize its distribution
+through the different seasons.
+
+
+_Influence of the Forest on the Humidity of the Soil._
+
+I have hitherto confined myself to the influence of the forest on
+meteorological conditions, a subject, as has been seen, full of
+difficulty and uncertainty. Its comparative effects on the temperature,
+the humidity, the texture and consistence, the configuration and
+distribution of the mould or arable soil, and, very often, of the
+mineral strata below, and on the permanence and regularity of springs
+and greater superficial watercourses, are much less disputable as well
+as more easily estimated, and much more important, than its possible
+value as a cause of strictly climatic equilibrium or disturbance.
+
+The action of the forest on the earth is chiefly mechanical, but the
+organic process of abstraction of water by its roots affects the
+quantity of that fluid contained in the vegetable mould, and in the
+mineral strata near the surface, and, consequently, the consistency of
+the soil. In treating of the effects of trees on the moisture of the
+atmosphere, I have said that the forest, by interposing a canopy between
+the sky and the ground, and by covering the surface with a thick mantle
+of fallen leaves, at once obstructed insolation and prevented the
+radiation of heat from the earth. These influences go far to balance
+each other; but familiar observation shows that, in summer, the forest
+soil is not raised to so high a temperature as open grounds exposed to
+irradiation. For this reason, and in consequence of the mechanical
+resistance opposed by the bed of dead leaves to the escape of moisture,
+we should expect that, except after recent rains, the superficial strata
+of woodland soil would be more humid than that of cleared land. This
+agrees with experience. The soil of the forest is always moist, except
+in the extremest droughts, and it is exceedingly rare that a primitive
+wood suffers from want of humidity. How far this accumulation of water
+affects the condition of neighboring grounds by lateral infiltration, we
+do not know, but we shall see, in a subsequent chapter, that water is
+conveyed to great distances by this process, and we may hence infer that
+the influence in question is an important one.
+
+
+_Influence of the Forest on the Flow of Springs._
+
+It is well established that the protection afforded by the forest
+against the escape of moisture from its soil, insures the permanence and
+regularity of natural springs, not only within the limits of the wood,
+but at some distance beyond its borders, and thus contributes to the
+supply of an element essential to both vegetable and animal life. As the
+forests are destroyed, the springs which flowed from the woods, and,
+consequently, the greater watercourses fed by them, diminish both in
+number and in volume. This fact is so familiar throughout the American
+States and the British Provinces, that there are few old residents of
+the interior of those districts who are not able to testify to its truth
+as a matter of personal observation. My own recollection suggests to me
+many instances of this sort, and I remember one case where a small
+mountain spring, which disappeared soon after the clearing of the ground
+where it rose, was recovered about ten or twelve years ago, by simply
+allowing the bushes and young trees to grow up on a rocky knoll, not
+more than half an acre in extent, immediately above it, and has since
+continued to flow uninterruptedly. The uplands in the Atlantic States
+formerly abounded in sources and rills, but in many parts of those
+States which have been cleared for above a generation or two, the hill
+pastures now suffer severely from drought, and in dry seasons no longer
+afford either water or herbage for cattle.
+
+Foissac, indeed, quotes from the elder Pliny (_Nat. Hist._, xxxi, c. 30)
+a passage affirming that the felling of the woods gives rise to springs
+which did not exist before because the water of the soil was absorbed by
+the trees; and the same meteorologist declares, as I observed in
+treating of the effect of the forest on atmospheric humidity, that the
+planting of trees tends to drain marshy ground, because the roots absorb
+more water than falls from the air. But Pliny's statement rests on very
+doubtful authority, and Foissac cites no evidence in support of his own
+proposition.[193] In the American States, it is always observed that
+clearing the ground not only causes running springs to disappear, but
+dries up the stagnant pools and the spongy soils of the low grounds. The
+first roads in those States ran along the ridges, when practicable,
+because there only was the earth dry enough to allow of their
+construction, and, for the same reason, the cabins of the first settlers
+were perched upon the hills. As the forests have been from time to time
+removed, and the face of the earth laid open to the air and sun, the
+moisture has been evaporated, and the removal of the highways and of
+human habitations from the bleak hills to the sheltered valleys, is one
+of the most agreeable among the many improvements which later
+generations have witnessed in the interior of New England and the other
+Northern States.
+
+Almost every treatise on the economy of the forest adduces numerous
+facts in support of the doctrine that the clearing of the woods tends to
+diminish the flow of springs and the humidity of the soil, and it might
+seem unnecessary to bring forward further evidence on this point.[194]
+But the subject is of too much practical importance and of too great
+philosophical interest to be summarily disposed of; and it ought
+particularly to be noticed that there is at least one case--that of some
+loose soils which, when bared of wood, very rapidly absorb and transmit
+to lower strata the water they receive from the atmosphere, as argued by
+Valles[195]--where the removal of the forest may increase the flow of
+springs at levels below it, by exposing to the rain and melted snow a
+surface more bibulous, and at the same time less retentive, than its
+original covering. Under such circumstances, the water of precipitation,
+which had formerly flowed off without penetrating through the
+superficial layers of leaves upon the ground--as, in very heavy showers,
+it sometimes does--or been absorbed by the vegetable mould and retained
+until it was evaporated, might descend through porous earth until it
+meets an impermeable stratum, and then be conducted along it, until,
+finally, at the outcropping of this stratum, it bursts from a hillside
+as a running spring. But such instances are doubtless too rare to form a
+frequent or an important exception to the general law, because it is
+only under very uncommon circumstances that rain water runs off over the
+surface of forest ground instead of sinking into it, and very rarely the
+case that such a soil as has just been supposed is covered by a layer of
+vegetable earth thick enough to retain, until it is evaporated, all the
+rain that falls upon it, without imparting any water to the strata below
+it.
+
+If we look at the point under discussion as purely a question of fact,
+to be determined by positive evidence and not by argument, the
+observations of Boussingault are, both in the circumstances they detail,
+and in the weight of authority to be attached to the testimony, among
+the most important yet recorded. They are embodied in the fourth section
+of the twentieth chapter of that writer's _Economie Rurale_, and I have
+already referred to them on page 191 for another purpose. The interest
+of the question will justify me in giving, in Boussingault's own words,
+the facts and some of the remarks with which he accompanies the details
+of them: "In many localities," he observes,[196] "it has been thought
+that, within a certain number of years, a sensible diminution has been
+perceived in the volume of water of streams utilized as a motive power;
+at other points, there are grounds for believing that rivers have become
+shallower, and the increasing breadth of the belt of pebbles along their
+banks seems to prove the loss of a part of their water; and, finally,
+abundant springs have almost dried up. These observations have been
+principally made in valleys bounded by high mountains, and it is thought
+to have been noticed that this diminution of the waters has immediately
+followed the epoch when the inhabitants have begun to destroy,
+unsparingly, the woods which were spread over the face of the land.
+
+"These facts would indicate that, where clearings have been made,
+it rains less than formerly, and this is the generally received
+opinion. * * * But while the facts I have stated have been established,
+it has been observed, at the same time, that, since the clearing of the
+mountains, the rivers and the torrents, which seemed to have lost a part
+of their water, sometimes suddenly swell, and that, occasionally, to a
+degree which causes great disasters. Besides, after violent storms,
+springs which had become almost exhausted have been observed to burst
+out with impetuosity, and soon after to dry up again. These latter
+observations, it will be easily conceived, warn us not to admit hastily
+the common opinion that the felling of the woods lessens the quantity of
+rain; for not only is it very possible that the quantity of rain has not
+changed, but the mean volume of running water may have remained the
+same, in spite of the appearance of drought presented by the rivers and
+springs, at certain periods of the year. Perhaps the only difference
+would be that the flow of the same quantity of water becomes more
+irregular in consequence of clearing. For instance: if the low water of
+the Rhone during one part of the year were exactly compensated by a
+sufficient number of floods, it would follow that this river would
+convey to the Mediterranean the same volume of water which it carried to
+that sea in ancient times, before the period when the countries near its
+source were stripped of their woods, and when, probably, its mean depth
+was not subject to so great variations as in our days. If this were so,
+the forests would have this value--that of regulating, of economizing in
+a certain sort, the drainage of the rain water.
+
+"If running streams really become rarer in proportion as clearing is
+extended, it follows either that the rain is less abundant, or that
+evaporation is greatly favored by a surface which is no longer protected
+by trees against the rays of the sun and the wind. These two causes,
+acting in the same direction, must often be cumulative in their effects,
+and before we attempt to fix the value of each, it is proper to inquire
+whether it is an established fact that running waters diminish on the
+surface of a country in which extensive clearing is going on; in a word,
+to examine whether an apparent fact has not been mistaken for a real
+one. And here lies the practical point of the question; for if it is
+once established that clearing diminishes the volume of streams, it is
+less important to know to what special cause this effect is due. * * * I
+shall attach no value except to facts which have taken place under the
+eye of man, as it is the influence of his labors on the meteorological
+condition of the atmosphere which I propose to estimate. What I am about
+to detail has been observed particularly in America, but I shall
+endeavor to establish, that what I believe to be true of America would
+be equally so for any other continent.
+
+"One of the most interesting parts of Venezuela is, no doubt, the valley
+of Aragua. Situated at a short distance from the coast, and endowed,
+from its elevation, with various climates and a soil of unexampled
+fertility, its agriculture embraces at once the crops suited to tropical
+regions and to Europe. Wheat succeeds well on the heights of Victoria.
+Bounded on the north by the coast chain, on the south by a system of
+mountains connected with the Llanos, the valley is shut in on the east
+and the west by lines of hills which completely close it. In consequence
+of this singular configuration, the rivers which rise within it, having
+no outlet to the ocean, form, by their union, the beautiful Lake of
+Tacarigua or Valencia. This lake, according to Humboldt, is larger than
+that of Neufchatel; it is at an elevation of 439 metres [= 1,460 English
+feet] above the sea, and its greatest length does not exceed two leagues
+and a half [= seven English miles].
+
+"At the time of Humboldt's visit to the valley of Aragua, the
+inhabitants were struck by the gradual diminution which the lake had
+been undergoing for thirty years. In fact, by comparing the descriptions
+given by historians with its actual condition, even making large
+allowance for exaggeration, it was easy to see that the level was
+considerably depressed. The facts spoke for themselves. Oviedo, who,
+toward the close of the sixteenth century, had often traversed the
+valley of Aragua, says positively that New Valencia was founded, in
+1555, at half a league from the Lake of Tacarigua; in 1800, Humboldt
+found this city 5,260 metres [= 3-1/3 English miles] from the shore.
+
+"The aspect of the soil furnished new proofs. Many hillocks on the plain
+retain the name of islands, which they more justly bore when they were
+surrounded by water. The ground laid bare by the retreat of the lake was
+converted into admirable plantations of cotton, bananas, and sugar cane;
+and buildings erected near the lake showed the sinking of the water from
+year to year. In 1796, new islands made their appearance. An important
+military point, a fortress built in 1740 on the island of Cabrera, was
+now on a peninsula; and, finally, on two granitic islands, those of Cura
+and Cabo Blanco, Humboldt observed among the shrubs, some metres above
+the water, fine sand filled with helicites.
+
+"These clear and positive facts suggested numerous explanations, all
+assuming a subterranean outlet, which permitted the discharge of the
+water to the ocean. Humboldt disposed of these hypotheses, and, after a
+careful examination of the locality, the distinguished traveller did not
+hesitate to ascribe the diminution of the waters of the lake to the
+numerous clearings which had been made in the valley of Aragua within
+half a century. * * *
+
+"In 1800, the valley of Aragua possessed a population as dense as that
+of any of the best-peopled parts of France. * * * Such was the
+prosperous condition of this fine country when Humboldt occupied the
+Hacienda de Cura.
+
+"Twenty-two years later, I explored the valley of Aragua, fixing my
+residence in the little town of Maracay. For some years previous, the
+inhabitants had observed that the waters of the lake were no longer
+retiring, but, on the contrary, were sensibly rising. Grounds, not long
+before occupied by plantations, were submerged. The islands of Nuevas
+Aparecidas, which appeared above the surface in 1796, had again become
+shoals dangerous to navigation. Cabrera, a tongue of land on the north
+side of the valley, was so narrow that the least rise of the water
+completely inundated it. A protracted north wind sufficed to flood the
+road between Maracay and New Valencia. The fears which the inhabitants
+of the shores had so long entertained were reversed. * * * Those who had
+explained the diminution of the lake by the supposition of subterranean
+channels were suspected of blocking them up, to prove themselves in the
+right.
+
+"During the twenty-two years which had elapsed, important political
+events had occurred. Venezuela no longer belonged to Spain. The peaceful
+valley of Aragua had been the theatre of bloody struggles, and a war of
+extermination had desolated these smiling lands and decimated their
+population. At the first cry of independence a great number of slaves
+found their liberty by enlisting under the banners of the new republic;
+the great plantations were abandoned, and the forest, which in the
+tropics so rapidly encroaches, had soon recovered a large proportion of
+the soil which man had wrested from it by more than a century of
+constant and painful labor.
+
+"At the time of the growing prosperity of the valley of Aragua, the
+principal affluents of the lake were diverted, to serve for irrigation,
+and the rivers were dry for more than six months of the year. At the
+period of my visit, their waters, no longer employed, flowed freely."
+
+Boussingault proceeds to state that two lakes near Ubate in New Granada,
+at an elevation of 2,562 metres (= 8,500 English feet), where there is a
+constant temperature of 14 deg. to 16 deg. centigrade [= 57 deg., 61 deg. Fahrenheit],
+had formed but one, a century before his visit; that the waters were
+gradually retiring, and the plantations extending over the abandoned
+bed; that, by inquiry of old hunters and by examination of parish
+records, he found that extensive clearings had been made and were still
+going on.
+
+He found, also, that the length of the Lake of Fuquene, in the same
+valley, had, within two centuries, been reduced from ten leagues to one
+and a half, its breadth from three leagues to one. At the former period,
+timber was abundant, and the neighboring mountains were covered, to a
+certain height, with American oaks, laurels, and other trees of
+indigenous species; but at the time of his visit the mountains had been
+almost entirely stripped of their wood, chiefly to furnish fuel for
+salt-works. Our author adds that other cases, similar to those already
+detailed, might be cited, and he proceeds to show, by several examples,
+that the waters of other lakes in the same regions, where the valleys
+had always been bare of wood, or where the forests had not been
+disturbed, had undergone no change of level.
+
+Boussingault further maintains that the lakes of Switzerland have
+sustained a depression of level since the too prevalent destruction of
+the woods, and arrives at the general conclusion, that, "in countries
+where great clearings have been made, there has most probably been a
+diminution in the living waters which flow upon the surface of the
+ground." This conclusion he further supports by two examples: one, where
+a fine spring, at the foot of a wooded mountain in the Island of
+Ascension, dried up when the mountain was cleared, but reappeared when
+the wood was replanted; the other at Marmato, in the province of
+Popayan, where the streams employed to drive machinery were much
+diminished in volume, within two years after the clearing of the heights
+from which they derived their supplies. This latter is an interesting
+case, because, although the rain gauges, established as soon as the
+decrease of water began to excite alarm, showed a greater fall of rain
+for the second year of observation than the first, yet there was no
+appreciable increase in the flow of the mill streams. From these cases,
+the distinguished physicist infers that very restricted local clearings
+may diminish and even suppress springs and brooks, without any reduction
+in the total quantity of rain.
+
+It will have been noticed that these observations, with the exception of
+the last two cases, do not bear directly upon the question of the
+diminution of springs by clearings, but they logically infer it from the
+subsidence of the natural reservoirs which springs once filled. There
+is, however, no want of positive evidence on this subject.
+
+Marschand cites the following instances: "Before the felling of the
+woods, within the last few years, in the valley of the Soulce, the
+Combe-es-Mounin and the Little Valley, the Sorne furnished a regular
+and sufficient supply of water for the iron works of Unterwyl, which was
+almost unaffected by drought or by heavy rains. The Sorne has now become
+a torrent, every shower occasions a flood, and after a few days of fine
+weather, the current falls so low that it has been necessary to change
+the water wheels, because those of the old construction are no longer
+able to drive the machinery, and at last to introduce a steam engine to
+prevent the stoppage of the works for want of water.
+
+"When the factory of St. Ursanne was established, the river that
+furnished its power was abundant, long known and tried, and had, from
+time immemorial, sufficed for the machinery of a previous factory.
+Afterward, the woods near its sources were cut. The supply of water fell
+off in consequence, the factory wanted water for half the year, and was
+at last obliged to stop altogether.
+
+"The spring of Combefoulat, in the commune of Seleate, was well known as
+one of the best in the country; it was remarkably abundant and
+sufficient, in spite of the severest droughts, to supply all the
+fountains of the town; but, as soon as considerable forests were felled
+in Combe-de-pre Martin and in the valley of Combefoulat, the famous
+spring which lies below these woods has become a mere thread of water,
+and disappears altogether in times of drought.
+
+"The spring of Varieux, which formerly supplied the castle of Pruntrut,
+lost more than half its water after the clearing of Varieux and
+Rongeoles. These woods have been replanted, the young trees are growing
+well, and with the woods, the waters of the spring are increasing.
+
+"The Dog Spring between Pruntrut and Bressancourt has entirely vanished
+since the surrounding forests grounds were brought under cultivation.
+
+"The Wolf Spring, in the commune of Soubey, furnishes a remarkable
+example of the influence of the woods upon fountains. A few years ago
+this spring did not exist. At the place where it now rises, a small
+thread of water was observed after very long rains, but the stream
+disappeared with the rain. The spot is in the middle of a very steep
+pasture inclining to the south. Eighty years ago, the owner of the land,
+perceiving that young firs were shooting up in the upper part of it,
+determined to let them grow, and they soon formed a flourishing grove.
+As soon as they were well grown, a fine spring appeared in place of the
+occasional rill, and furnished abundant water in the longest droughts.
+For forty or fifty years, this spring was considered the best in the
+Clos du Doubs. A few years since, the grove was felled, and the ground
+turned again to a pasture. The spring disappeared with the wood, and is
+now as dry as it was ninety years ago."[197]
+
+"The influence of the forest on springs," says Hummel, "is strikingly
+shown by an instance at Heilbronn. The woods on the hills surrounding
+the town are cut in regular succession every twentieth year. As the
+annual cuttings approach a certain point, the springs yield less water,
+some of them none at all; but as the young growth shoots up, they now
+more and more freely, and at length bubble up again in all their
+original abundance."[198]
+
+Piper states the following case: "Within about half a mile of my
+residence there is a pond upon which mills have been standing for a long
+time, dating back, I believe, to the first settlement of the town. These
+have been kept in constant operation until within some twenty or thirty
+years, when the supply of water began to fail. The pond owes its
+existence to a stream which has its source in the hills which stretch
+some miles to the south. Within the time mentioned, these hills, which
+were clothed with a dense forest, have been almost entirely stripped of
+trees; and to the wonder and loss of the mill owners, the water in the
+pond has failed, except in the season of freshets; and, what was never
+heard of before, the stream itself has been entirely dry. Within the
+last ten years a new growth of wood has sprung up on most of the land
+formerly occupied by the old forest; and now the water runs through the
+year, notwithstanding the great droughts of the last few years, going
+back from 1856."
+
+Dr. Piper quotes from a letter of William C. Bryant the following
+remarks: "It is a common observation that our summers are become drier,
+and our streams smaller. Take the Cuyahoga as an illustration. Fifty
+years ago large barges loaded with goods went up and down that river,
+and one of the vessels engaged in the battle of Lake Erie, in which the
+gallant Perry was victorious, was built at Old Portage, six miles north
+of Albion, and floated down to the lake. Now, in an ordinary stage of
+the water, a canoe or skiff can hardly pass down the stream. Many a boat
+of fifty tons burden has been built and loaded in the Tuscarawas, at New
+Portage, and sailed to New Orleans without breaking bulk. Now, the river
+hardly affords a supply of water at New Portage for the canal. The same
+may be said of other streams--they are drying up. And from the same
+cause--the destruction of our forests--our summers are growing drier,
+and our winters colder."[199]
+
+No observer has more carefully studied the influence of the forest upon
+the flow of the waters, or reasoned more ably on the ascertained
+phenomena than Cantegril. The facts presented in the following case,
+communicated by him to the _Ami des Sciences_ for December, 1859, are as
+nearly conclusive as any single instance well can be:
+
+"In the territory of the commune of Labruguiere, there is a forest of
+1,834 hectares [4,530 acres], known by the name of the Forest of
+Montaut, and belonging to that commune. It extends along the northern
+slope of the Black Mountains. The soil is granitic, the maximum altitude
+1,243 metres [4,140 feet], and the inclination ranges between 15 and 60
+to 100.
+
+"A small current of water, the brook of Caunan, takes its rise in this
+forest, and receives the waters of two thirds of its surface. At the
+lower extremity of the wood and on the stream are several fulleries,
+each requiring a force of eight horse-power to drive the water wheels
+which work the stampers. The commune of Labruguiere had been for a long
+time famous for its opposition to forest laws. Trespasses and abuses of
+the right of pasturage had converted the wood into an immense waste, so
+that this vast property now scarcely sufficed to pay the expense of
+protecting it, and to furnish the inhabitants with a meagre supply of
+fuel. While the forest was thus ruined, and the soil thus bared, the
+water, after every abundant rain, made an eruption into the valley,
+brought down a great quantity of pebbles which still clog the current of
+the Caunan. The violence of the floods was sometimes such that they were
+obliged to stop the machinery for some time. During the summer another
+inconvenience was felt. If the dry weather continued a little longer
+than usual, the delivery of water became insignificant. Each fullery
+could for the most part only employ a single set of stampers, and it was
+not unusual to see the work entirely suspended.
+
+"After 1840, the municipal authority succeeded in enlightening the
+population as to their true interests. Protected by a more watchful
+supervision, aided by well-managed replantation, the forest has
+continued to improve to the present day. In proportion to the
+restoration of the forest, the condition of the manufactories has become
+less and less precarious, and the action of the water is completely
+modified. For example, there are, no longer, sudden and violent floods
+which make it necessary to stop the machinery. There is no increase in
+the delivery until six or eight hours after the beginning of the rain;
+the floods follow a regular progression till they reach their maximum,
+and decrease in the same manner. Finally, the fulleries are no longer
+forced to suspend work in summer; the water is always sufficiently
+abundant to allow the employment of two sets of stampers at least, and
+often even of three.
+
+"This example is remarkable in this respect, that, all other
+circumstances having remained the same, the changes in the action of the
+stream can be attributed only to the restoration of the forest--changes
+which may be thus summed up: diminution of flood water during
+rains--increase of delivery at other seasons."
+
+
+_The Forest in Winter._
+
+To estimate rightly the importance of the forest as a natural apparatus
+for accumulating the water that falls upon the surface and transmitting
+it to the subjacent strata, we must compare the condition and properties
+of its soil with those of cleared and cultivated earth, and examine the
+consequently different action of these soils at different seasons of the
+year. The disparity between them is greatest in climates where, as in
+the Northern American States and in the North of Europe, the open ground
+freezes and remains impervious to water during a considerable part of
+the winter; though, even in climates where the earth does not freeze at
+all, the woods have still an important influence of the same character.
+The difference is yet greater in countries which have regular wet and
+dry seasons, rain being very frequent in the former period, while, in
+the latter, it scarcely occurs at all. These countries lie chiefly in or
+near the tropics, but they are not wanting in higher latitudes; for a
+large part of Asiatic and even of European Turkey is almost wholly
+deprived of summer rains. In the principal regions occupied by European
+cultivation, and where alone the questions discussed in this volume are
+recognized as having, at present, any practical importance, rain falls
+at all seasons, and it is to these regions that, on this point as well
+as others, I chiefly confine my attention.
+
+The influence of the forest upon the waters of the earth has been more
+studied in France than in any other part of the civilized world, because
+that country has, in recent times, suffered most severely from the
+destruction of the woods. But in the southern provinces of that empire,
+where the evils resulting from this cause are most sensibly felt, the
+winters are not attended with much frost, while, in Northern Europe,
+where the winters are rigorous enough to freeze the ground to the depth
+of some inches, or even feet, a humid atmosphere and frequent summer
+rains prevent the drying up of the springs observed in southern
+latitudes when the woods are gone. For these reasons, the specific
+character of the forest, as a winter reservoir of moisture in countries
+with a cold and dry atmosphere, has not attracted so much attention in
+France and Northern Europe as it deserves in the United States, where an
+excessive climate renders that function of the woods more important.
+
+In New England, irregular as the climate is, the first autumnal snows
+usually fall before the ground is frozen at all, or when the frost
+extends at most to the depth of only a few inches. In the woods,
+especially those situated upon the elevated ridges which supply the
+natural irrigation of the soil and feed the perennial fountains and
+streams, the ground remains covered with snow during the winter; for the
+trees protect the snow from blowing from the general surface into the
+depressions, and new accessions are received before the covering
+deposited by the first fall is melted. Snow is of a color unfavorable
+for radiation, but, even when it is of considerable thickness, it is not
+wholly impervious to the rays of the sun, and for this reason, as well
+as from the warmth of lower strata, the frozen crust, if one has been
+formed, is soon thawed, and does not again fall below the freezing point
+during the winter.
+
+The snow in contact with the earth now begins to melt, with greater or
+less rapidity, according to the relative temperature of the earth and
+the air, while the water resulting from its dissolution is imbibed by
+the vegetable mould, and carried off by infiltration so fast that both
+the snow and the layers of leaves in contact with it often seem
+comparatively dry, when, in fact, the under surface of the former is in
+a state of perpetual thaw. No doubt a certain proportion of the snow is
+returned to the atmosphere by direct evaporation, but in the woods it is
+partially protected from the action of the sun, and as very little water
+runs off in the winter by superficial watercourses, except in rare cases
+of sudden thaw, there can be no question that much the greater part of
+the snow deposited in the forest is slowly melted and absorbed by the
+earth.
+
+The quantity of snow that falls in extensive forests, far from the open
+country, has seldom been ascertained by direct observation, because
+there are few meteorological stations in such situations. In the
+Northeastern border States of the American Union, the ground in the deep
+woods is covered with snow four or five months, and the proportion of
+water which falls in snow does not exceed one fifth of the total
+precipitation for the year.[200] Although, in the open grounds, snow and
+ice are evaporated with great rapidity in clear weather, even when the
+thermometer stands far below the freezing point, the surface of the snow
+in the woods does not indicate much loss in this way. Very small
+deposits of snowflakes remain unevaporated in the forest, for many days
+after snow let fall at the same time in the cleared field has
+disappeared without either a thaw to melt it or a wind powerful enough
+to drift it away. Even when bared of their leaves, the trees of a wood
+obstruct, in an important degree, both the direct action of the sun's
+rays on the snow, and the movement of drying and thawing winds.
+
+Dr. Piper records the following observations: "A body of snow, one foot
+in depth, and sixteen feet square, was protected from the wind by a
+tight board fence about five feet high, while another body of snow, much
+more sheltered from the sun than the first, six feet in depth, and about
+sixteen feet square, was fully exposed to the wind. When the thaw came
+on, which lasted about a fortnight, the larger body of snow was entirely
+dissolved in less than a week, while the smaller body was not wholly
+gone at the end of the second week.
+
+"Equal quantities of snow were placed in vessels of the same kind and
+capacity, the temperature of the air being seventy degrees. In the one
+case, a constant current of air was kept passing over the open vessel,
+while the other was protected by a cover. The snow in the first was
+dissolved in sixteen minutes, while the latter had a small unthawed
+proportion remaining at the end of eighty-five minutes."[201]
+
+The snow in the woods is protected in the same way, though not literally
+to the same extent as by the fence in one of these cases and the cover
+in the other. Little of the winter precipitation, therefore, is lost by
+evaporation, and as it slowly melts at bottom it is absorbed by the
+earth, and but a very small quantity of water runs off from the surface.
+The immense importance of the forest, as a reservoir of this stock of
+moisture, becomes apparent, when we consider that a large proportion of
+the summer rain either flows into the valleys and the rivers, because it
+falls faster than the ground can imbibe it; or, if absorbed by the warm
+superficial strata, is evaporated from them without sinking deep enough
+to reach wells and springs, which, of course, depend very much on winter
+rains and snows for their entire supply. This observation, though
+specially true of cleared and cultivated grounds, is not wholly
+inapplicable to the forest, particularly when, as is too often the case
+in Europe, the underwood and the decaying leaves are removed.
+
+The general effect of the forest in cold climates is to assimilate the
+winter state of the ground to that of wooded regions under softer skies;
+and it is a circumstance well worth noting, that in Southern Europe,
+where nature has denied to the earth a warm winter-garment of flocculent
+snow, she has, by one of those compensations in which her empire is so
+rich, clothed the hillsides with umbrella pines, ilexes, cork oaks, and
+other trees of persistent foliage, whose evergreen leaves afford to the
+soil a protection analogous to that which it derives from snow in more
+northern climates.
+
+The water imbibed by the soil in winter sinks until it meets a more or
+less impermeable, or a saturated stratum, and then, by unseen conduits,
+slowly finds its way to the channels of springs, or oozes out of the
+ground in drops which unite in rills, and so all is conveyed to the
+larger streams, and by them finally to the sea. The water, in
+percolating through the vegetable and mineral layers, acquires their
+temperature, and is chemically affected by their action, but it carries
+very little matter in mechanical suspension.
+
+The process I have described is a slow one, and the supply of moisture
+derived from the snow, augmented by the rains of the following seasons,
+keeps the forest ground, where the surface is level or but moderately
+inclined, in a state of saturation through almost the whole year. The
+rivers fed by springs and shaded by woods are comparatively uniform in
+volume, in temperature, and in chemical composition. Their banks are
+little abraded, nor are their courses much obstructed by fallen timber,
+or by earth and gravel washed down from the highlands. Their channels
+are subject only to slow and gradual changes, and they carry down to the
+lakes and the sea no accumulation of sand or silt to fill up their
+outlets, and, by raising their beds, to force them to spread over the
+low grounds near their mouth.[202]
+
+In this state of things, destructive tendencies of all sorts are
+arrested or compensated, and tree, bird, beast, and fish, alike, find a
+constant uniformity of condition most favorable to the regular and
+harmonious coexistence of them all.
+
+
+_General Consequences of the Destruction of the Forest._
+
+With the disappearance of the forest, all is changed. At one season, the
+earth parts with its warmth by radiation to an open sky--receives, at
+another, an immoderate heat from the unobstructed rays of the sun. Hence
+the climate becomes excessive, and the soil is alternately parched by
+the fervors of summer, and seared by the rigors of winter. Bleak winds
+sweep unresisted over its surface, drift away the snow that sheltered it
+from the frost, and dry up its scanty moisture. The precipitation
+becomes as regular as the temperature; the melting snows and vernal
+rains, no longer absorbed by a loose and bibulous vegetable mould, rush
+over the frozen surface, and pour down the valleys seaward, instead of
+filling a retentive bed of absorbent earth, and storing up a supply of
+moisture to feed perennial springs. The soil is bared of its covering of
+leaves, broken and loosened by the plough, deprived of the fibrous
+rootlets which held it together, dried and pulverized by sun and wind,
+and at last exhausted by new combinations. The face of the earth is no
+longer a sponge, but a dust heap, and the floods which the waters of the
+sky pour over it hurry swiftly along its slopes, carrying in suspension
+vast quantities of earthy particles which increase the abrading power
+and mechanical force of the current, and, augmented by the sand and
+gravel of falling banks, fill the beds of the streams, divert them into
+new channels and obstruct their outlets. The rivulets, wanting their
+former regularity of supply and deprived of the protecting shade of the
+woods, are heated, evaporated, and thus reduced in their summer
+currents, but swollen to raging torrents in autumn and in spring. From
+these causes, there is a constant degradation of the uplands, and a
+consequent elevation of the beds of watercourses and of lakes by the
+deposition of the mineral and vegetable matter carried down by the
+waters. The channels of great rivers become unnavigable, their estuaries
+are choked up, and harbors which once sheltered large navies are shoaled
+by dangerous sandbars. The earth, stripped of its vegetable glebe, grows
+less and less productive, and, consequently, less able to protect itself
+by weaving a new network of roots to bind its particles together, a new
+carpeting of turf to shield it from wind and sun and scouring rain.
+Gradually it becomes altogether barren. The washing of the soil from the
+mountains leaves bare ridges of sterile rock, and the rich organic mould
+which covered them, now swept down into the dank low grounds, promotes a
+luxuriance of aquatic vegetation that breeds fever, and more insidious
+forms of mortal disease, by its decay, and thus the earth is rendered no
+longer fit for the habitation of man.[203]
+
+To the general truth of this sad picture there are many exceptions, even
+in countries of excessive climates. Some of these are due to favorable
+conditions of surface, of geological structure, and of the distribution
+of rain; in many others, the evil consequences of man's improvidence
+have not yet been experienced, only because a sufficient time has not
+elapsed, since the felling of the forest, to allow them to develop
+themselves. But the vengeance of nature for the violation of her
+harmonies, though slow, is sure, and the gradual deterioration of soil
+and climate in such exceptional regions is as certain to result from the
+destruction of the woods as is any natural effect to follow its cause.
+
+In the vast farrago of crudities which the elder Pliny's ambition of
+encyclopaedic attainment and his ready credulity have gathered together,
+we meet some judicious observations. Among these we must reckon the
+remark with which he accompanies his extraordinary statement respecting
+the prevention of springs by the growth of forest trees, though, as is
+usual with him, his philosophy is wrong. "Destructive torrents are
+generally formed when hills are stripped of the trees which formerly
+confined and absorbed the rains." The absorption here referred to is not
+that of the soil, but of the roots, which, Pliny supposed, drank up the
+water to feed the growth of the trees.
+
+Although this particular evil effect of too extensive clearing was so
+early noticed, the lesson seems to have been soon forgotten. The
+legislation of the Middle Ages in Europe is full of absurd provisions
+concerning the forests, which sovereigns sometimes destroyed because
+they furnished a retreat for rebels and robbers, sometimes protected
+because they were necessary to breed stags and boars for the chase, and
+sometimes spared with the more enlightened view of securing a supply of
+timber and of fuel to future generations.[204] It was reserved to later
+ages to appreciate their geographical importance, and it is only in very
+recent times, only in a few European countries, that the too general
+felling of the woods has been recognized as the most destructive among
+the many causes of the physical deterioration of the earth.
+
+
+_Condition of the Forest, and its Literature in different Countries._
+
+The literature of the forest, which in England and America has not yet
+become sufficiently extensive to be known as a special branch of
+authorship, counts its thousands of volumes in Germany, Italy, and
+France. It is in the latter country, perhaps, that the relations of the
+woods to the regular drainage of the soil, and especially to the
+permanence of the natural configuration of terrestrial surface, have
+been most thoroughly investigated. On the other hand, the purely
+economical aspects of sylviculture have been most satisfactorily
+expounded, and that art has been most philosophically discussed, and
+most skilfully and successfully practised, in Germany.
+
+The eminence of Italian theoretical hydrographers and the great ability
+of Italian hydraulic engineers are well known, but the specific
+geographical importance of the woods has not been so clearly recognized
+in Italy as in the states bordering it on the north and west. It is true
+that the face of nature has been as completely revolutionized by man,
+and that the action of torrents has created as wide and as hopeless
+devastation in that country as in France; but in the French Empire the
+desolation produced by clearing the forests is more recent,[205] has
+been more suddenly effected, and, therefore, excites a livelier and more
+general interest than in Italy, where public opinion does not so readily
+connect the effect with its true cause. Italy, too, from ancient habit,
+employs little wood in architectural construction; for generations she
+has maintained no military or commercial marine large enough to require
+exhaustive quantities of timber,[206] and the mildness of her climate
+makes small demands on the woods for fuel. Besides these circumstances,
+it must be remembered that the sciences of observation did not become
+knowledges of practical application till after the mischief was already
+mainly done and even forgotten in Alpine Italy, while its evils were
+just beginning to be sensibly felt in France when the claims of natural
+philosophy as a liberal study were first acknowledged in modern Europe.
+The former political condition of the Italian Peninsula would have
+effectually prevented the adoption of a general system of forest
+economy, however clearly the importance of a wise administration of this
+great public interest might have been understood. The woods which
+controlled and regulated the flow of the river sources were very often
+in one jurisdiction, the plains to be irrigated, or to be inundated by
+floods and desolated by torrents, in another. Concert of action on such
+a subject between a multitude of jealous petty sovereignties was
+obviously impossible, and nothing but the union of all the Italian
+states under a single government can render practicable the
+establishment of such arrangements for the conservation and restoration
+of the forests and the regulation of the flow of the waters as are
+necessary for the full development of the yet unexhausted resources of
+that fairest of lands, and even for the permanent maintenance of the
+present condition of its physical geography.
+
+The denudation of the Central and Southern Apennines and of the Italian
+declivity of the Western Alps began at a period of unknown antiquity,
+but it does not seem to have been carried to a very dangerous length
+until the foreign conquests and extended commerce of Rome created a
+greatly increased demand for wood for the construction of ships and for
+military material. The Eastern Alps, the Western Apennines, and the
+Maritime Alps retained their forests much later; but even here the want
+of wood, and the injury to the plains and the navigation of the rivers
+by sediment brought down by the torrents, led to some legislation for
+the protection of the forests, by the Republic of Venice in the
+fifteenth century, by that of Genoa as early at least as the
+seventeenth; and Marschand states that the latter Government passed laws
+requiring the proprietors of mountain lands to replant the woods. These,
+however, do not seem to have been effectually enforced. It is very
+common in Italy to ascribe to the French occupation under the first
+Empire all the improvements, and all the abuses of recent times,
+according to the political sympathies of the individual; and the French
+are often said to have prostrated every forest which has disappeared
+within a century.[207] But, however this may be, no energetic system of
+repression or restoration was adopted by any of the Italian states after
+the downfall of the Empire, and the taxes on forest property in some of
+them were so burdensome that rural municipalities sometimes proposed to
+cede their common woods to the Government, without any other
+compensation than the remission of the taxes imposed on forest
+lands.[208] Under such circumstances, woodlands would soon become
+disafforested, and where facilities of transportation and a good demand
+for timber have increased the inducements to fell it, as upon the
+borders of the Mediterranean, the destruction of the forest and all the
+evils which attend it have gone on at a seriously alarming rate. It has
+even been calculated that four tenths of the area of the Ligurian
+provinces have been washed away or rendered incapable of cultivation by
+the felling of the woods.[209]
+
+The damp and cold climate of England requires the maintenance of
+household fires through a large part of the year. Contrivances for
+economizing fuel were of later introduction in that country than on the
+Continent. The soil, like the sky, was, in general, charged with
+humidity; its natural condition was unfavorable for common roads, and
+the transportation of so heavy a material as coal, by land, from the
+remote counties where alone it was mined in the Middle Ages, was costly
+and difficult. For all these reasons, the consumption of wood was large,
+and apprehensions of the exhaustion of the forests were excited at an
+early period. Legislation there, as elsewhere, proved ineffectual to
+protect them, and many authors of the sixteenth century express fears of
+serious evils from the wasteful economy of the people in this respect.
+Harrison, in his curious chapter "Of Woods and Marishes" in Holinshed's
+compilation, complains of the rapid decrease of the forests, and adds:
+"Howbeit thus much I dare affirme, that if woods go so fast to decaie in
+the next hundred yeere of Grace, as they haue doone and are like to doo
+in this, * * * it is to be feared that the fennie bote, broome, turfe,
+gall, heath, firze, brakes, whinnes, ling, dies, hassacks, flags, straw,
+sedge, reed, rush, and also _seacole_, will be good merchandize euen
+in the citie of London, whereunto some of them euen now haue gotten
+readie passage, and taken vp their innes in the greatest merchants'
+parlours. * * * I would wish that I might liue no longer than to see
+foure things in this land reformed, that is: the want of discipline in
+the church: the couetous dealing of most of our merchants in the
+preferment of the commodities of other countries, and hinderance of
+their owne: the holding of faires and markets vpon the sundaie to be
+abolished and referred to the wednesdaies: and that euerie man, in
+whatsoeuer part of the champaine soile enioieth fortie acres of land,
+and vpwards, after that rate, either by free deed, copie hold, or fee
+farme, might plant one acre of wood, or sowe the same with oke mast,
+hasell, beech, and sufficient prouision be made that it may be cherished
+and kept. But I feare me that I should then liue too long, and so long,
+that I should either be wearie of the world, or the world of me."[210]
+Evelyn's "Silva," the first edition of which appeared in 1664, rendered
+an extremely important service to the cause of the woods, and there is
+no doubt that the ornamental plantations in which England far surpasses
+all other countries, are, in some measure, the fruit of Evelyn's
+enthusiasm. In England, however, arboriculture, the planting and nursing
+of single trees, has, until recently, been better understood than
+sylviculture, the sowing and training of the forest. But this latter
+branch of rural improvement is now pursued on a very considerable scale,
+though, so far as I know, not by the National Government.
+
+
+_The Influence of the Forest on Inundations._
+
+Besides the climatic question, which I have already sufficiently
+discussed, and the obvious inconveniences of a scanty supply of
+charcoal, of fuel, and of timber for architectural and naval
+construction and for the thousand other uses to which wood is applied in
+rural and domestic economy, and in the various industrial processes of
+civilized life, the attention of French foresters and public economists
+has been specially drawn to three points, namely: the influence of the
+forests on the permanence and regular flow of springs or natural
+fountains; on inundations by the overflow of rivers; and on the abrasion
+of soil and the transportation of earth, gravel, pebbles, and even of
+considerable masses of rock, from higher to lower levels, by torrents.
+There are, however, connected with this general subject, several other
+topics of minor or strictly local interest, or of more uncertain
+character, which I shall have occasion more fully to speak of hereafter.
+
+The first of these three principal subjects--the influence of the woods
+on springs and other living waters--has been already considered; and if
+the facts stated in that discussion are well established, and the
+conclusions I have drawn from them are logically sound, it would seem to
+follow, as a necessary corollary, that the action of the forest is as
+important in diminishing the frequency and violence of river floods, as
+in securing the permanence and equability of natural fountains; for any
+cause which promotes the absorption and accumulation of the water of
+precipitation by the superficial strata of the soil, to be slowly given
+out by infiltration and percolation, must, by preventing the rapid flow
+of surface water into the natural channels of drainage, tend to check
+the sudden rise of rivers, and, consequently, the overflow of their
+banks, which constitutes what is called inundation. The mechanical
+resistance, too, offered by the trunks of trees and of undergrowth to
+the flow of water over the surface, tends sensibly to retard the
+rapidity of its descent down declivities, and to divert and divide
+streams which may have already accumulated from smaller threads of
+water.[211]
+
+Inundations are produced by the insufficiency of the natural channels of
+rivers to carry off the waters of their basins as fast as those waters
+flow into them. In accordance with the usual economy of nature, we
+should presume that she had everywhere provided the means of
+discharging, without disturbance of her general arrangements or abnormal
+destruction of her products, the precipitation which she sheds upon the
+face of the earth. Observation confirms this presumption, at least in
+the countries to which I confine my inquiries; for, so far as we know
+the primitive conditions of the regions brought under human occupation
+within the historical period, it appears that the overflow of river
+banks was much less frequent and destructive than at the present day,
+or, at least, that rivers rose and fell less suddenly before man had
+removed the natural checks to the too rapid drainage of the basins in
+which their tributaries originate. The banks of the rivers and smaller
+streams in the North American colonies were formerly little abraded by
+the currents. Even now the trees come down almost to the water's edge
+along the rivers, in the larger forests of the United States, and the
+surface of the streams seems liable to no great change in level or in
+rapidity of current. A circumstance almost conclusive as to the
+regularity of flow in forest rivers, is that they do not form large
+sedimentary deposits, at their points of discharge into lakes or larger
+streams, such accumulations beginning, or at least advancing far more
+rapidly, after the valleys are cleared.
+
+In the Northern United States, although inundations are sometimes
+produced in the height of summer by heavy rains, it will be found
+generally true that the most rapid rise of the waters, and, of course,
+the most destructive "freshets," as they are called in America, are
+produced by the sudden dissolution of the snow before the open ground is
+thawed in the spring. It frequently happens that a powerful thaw sets in
+after a long period of frost, and the snow which had been months in
+accumulating is dissolved and carried off in a few hours. When the snow
+is deep, it, to use a popular expression, "takes the frost out of the
+ground" in the woods, and, if it lies long enough, in the fields also.
+But the heaviest snows usually fall after midwinter, and are succeeded
+by warm rains or sunshine, which dissolve the snow on the cleared land
+before it has had time to act upon the frost-bound soil beneath it. In
+this case, the snow in the woods is absorbed as fast as it melts, by the
+soil it has protected from freezing, and does not materially contribute
+to swell the current of the rivers. If the mild weather, in which great
+snowstorms usually occur, does not continue and become a regular thaw,
+it is almost sure to be followed by drifting winds, and the inequality
+with which they distribute the snow leaves the ridges comparatively
+bare, while the depressions are often filled with drifts to the height
+of many feet. The knolls become frozen to a great depth; succeeding
+partial thaws melt the surface snow, and the water runs down into the
+furrows of ploughed fields, and other artificial and natural hollows,
+and then often freezes to solid ice. In this state of things, almost the
+entire surface of the cleared land is impervious to water, and from the
+absence of trees and the general smoothness of the ground, it offers
+little mechanical resistance to superficial currents. If, under these
+circumstances, warm weather accompanied by rain occurs, the rain and
+melted snow are swiftly hurried to the bottom of the valleys and
+gathered to raging torrents.
+
+It ought further to be considered that, though the lighter ploughed
+soils readily imbibe a great deal of water, yet the grass lands, and all
+the heavy and tenacious earths, absorb it in much smaller quantities,
+and less rapidly than the vegetable mould of the forest. Pasture,
+meadow, and clayey soils, taken together, greatly predominate over the
+sandy ploughed fields, in all large agricultural districts, and hence,
+even if, in the case we are supposing, the open ground chance to have
+been thawed before the melting of the snow which covers it, it is
+already saturated with moisture, or very soon becomes so, and, of
+course, cannot relieve the pressure by absorbing more water. The
+consequence is that the face of the country is suddenly flooded with a
+quantity of melted snow and rain equivalent to a fall of six or eight
+inches of the latter, or even more. This runs unobstructed to rivers
+often still bound with thick ice, and thus inundations of a fearfully
+devastating character are produced. The ice bursts, from the hydrostatic
+pressure from below, or is violently torn up by the current, and is
+swept by the impetuous stream, in large masses and with resistless fury,
+against banks, bridges, dams, and mills erected near them. The bark of
+the trees along the rivers is often abraded, at a height of many feet
+above the ordinary water level, by cakes of floating ice, which are at
+last stranded by the receding flood on meadow or ploughland, to delay,
+by their chilling influence, the advent of the tardy spring.
+
+The surface of a forest, in its natural condition, can never pour forth
+such deluges of water as flow from cultivated soil. Humus, or vegetable
+mould, is capable of absorbing almost twice its own weight of water. The
+soil in a forest of deciduous foliage is composed of humus, more or less
+unmixed, to the depth of several inches, sometimes even of feet, and
+this stratum is usually able to imbibe all the water possibly resulting
+from the snow which at any one time covers it. But the vegetable mould
+does not cease to absorb water when it becomes saturated, for it then
+gives off a portion of its moisture to the mineral earth below, and thus
+is ready to receive a new supply; and, besides, the bed of leaves not
+yet converted to mould takes up and retains a very considerable
+proportion of snow water, as well as of rain.
+
+In the warm climates of Southern Europe, as I have already said, the
+functions of the forest, so far as the disposal of the water of
+precipitation is concerned, are essentially the same at all seasons, and
+are analogous to those which it performs in the Northern United States
+in summer. Hence, in the former countries, the winter floods have not
+the characteristics which mark them in the latter, nor is the
+conservative influence of the woods in winter relatively so important,
+though it is equally unquestionable.
+
+If the summer floods in the United States are attended with less
+pecuniary damage than those of the Loire and other rivers of France, the
+Po and its tributaries in Italy, the Emme and her sister torrents which
+devastate the valleys of Switzerland, it is partly because the banks of
+American rivers are not yet lined with towns, their shores and the
+bottoms which skirt them not yet covered with improvements whose cost is
+counted by millions, and, consequently, a smaller amount of property is
+exposed to injury by inundation. But the comparative exemption of the
+American people from the terrible calamities which the overflow of
+rivers has brought on some of the fairest portions of the Old World, is,
+in a still greater degree, to be ascribed to the fact that, with all our
+thoughtless improvidence, we have not yet bared all the sources of our
+streams, not yet overthrown all the barriers which nature has erected to
+restrain her own destructive energies. Let us be wise in time, and
+profit by the errors of our older brethren!
+
+The influence of the forest in preventing inundations has been very
+generally recognized, both as a theoretical inference and as a fact of
+observation; but Belgrand and his commentator Valles have deduced an
+opposite result from various facts of experience and from scientific
+considerations. They contend that the superficial drainage is more
+regular from cleared than from wooded ground, and that clearing
+diminishes rather than augments the intensity of inundations. Neither of
+these conclusions is warranted by their data or their reasoning, and
+they rest partly upon facts, which, truly interpreted, are not
+inconsistent with the received opinions on these subjects, partly upon
+assumptions which are contradicted by experience. Two of these latter
+are, first, that the fallen leaves in the forest constitute an
+impermeable covering of the soil over, not through, which the water of
+rains and of melting snows flows off, and secondly, that the roots of
+trees penetrate and choke up the fissures in the rocks, so as to impede
+the passage of water through channels which nature has provided for its
+descent to lower strata.
+
+As to the first of these, we may appeal to familiar facts within the
+personal knowledge of every man acquainted with the operations of sylvan
+nature. I have before me a letter from an acute and experienced
+observer, containing this paragraph: "I think that rain water does not
+ever, except in very trifling quantities, flow over the leaves in the
+woods in summer or autumn. Water runs over them only in the spring, when
+they are pressed down smoothly and compactly, a state in which they
+remain only until they are dry, when shrinkage and the action of the
+wind soon roughen the surface so as effectually to stop, by absorption,
+all flow of water." I have observed that when a sudden frost succeeds a
+thaw at the close of the winter after the snow has principally
+disappeared, the water in and between the layers of leaves sometimes
+freezes into a solid crust, which allows the flow of water over it. But
+this occurs only in depressions and on a very small scale; and the ice
+thus formed is so soon dissolved that no sensible effect is produced on
+the escape of water from the general surface.
+
+As to the influence of roots upon drainage, I believe there is no doubt
+that they, independently of their action as absorbents, mechanically
+promote it. Not only does the water of the soil follow them
+downward,[212] but their swelling growth powerfully tends to enlarge the
+crevices of rock into which they enter; and as the fissures in rocks are
+longitudinal, not mere circular orifices, every line of additional width
+gained by the growth of roots within them increases the area of the
+crevice in proportion to its length. Consequently, the widening of a
+fissure to the extent of one inch might give an additional drainage
+equal to a square foot of open tubing.
+
+The observations and reasonings of Belgrand and Valles, though their
+conclusions have not been accepted by many, are very important in one
+point of view. These writers insist much on the necessity of taking into
+account, in estimating the relations between precipitation and
+evaporation, the abstraction of water from the surface and surface
+currents, by absorption and infiltration--an element unquestionably of
+great value, but hitherto much neglected by meteorological inquirers,
+who have very often reasoned as if the surface earth were either
+impermeable to water, or already saturated with it; whereas, in fact, it
+is a sponge, always imbibing humidity and always giving it off, not by
+evaporation only, but by infiltration and percolation.
+
+The destructive effects of inundations considered simply as a mechanical
+power by which life is endangered, crops destroyed, and the artificial
+constructions of man overthrown, are very terrible. Thus far, however,
+the flood is a temporary and by no means an irreparable evil, for if its
+ravages end here, the prolific powers of nature and the industry of man
+soon restore what had been lost, and the face of the earth no longer
+shows traces of the deluge that had overwhelmed it. Inundations have
+even their compensations. The structures they destroy are replaced by
+better and more secure erections, and if they sweep off a crop of corn,
+they not unfrequently leave behind them, as they subside, a fertilizing
+deposit which enriches the exhausted field for a succession of
+seasons.[213] If, then, the too rapid flow of the surface waters
+occasioned no other evil than to produce, once in ten years upon the
+average, an inundation which should destroy the harvest of the low
+grounds along the rivers, the damage would be too inconsiderable, and of
+too transitory a character, to warrant the inconveniences and the
+expense involved in the measures which the most competent judges in many
+parts of Europe believe the respective governments ought to take to
+obviate it.
+
+
+_Destructive Action of Torrents._
+
+But the great, the irreparable, the appalling mischiefs which have
+already resulted, and threaten to ensue on a still more extensive scale
+hereafter, from too rapid superficial drainage, are of a properly
+geographical character, and consist primarily in erosion, displacement,
+and transportation of the superficial strata, vegetable and mineral--of
+the integuments, so to speak, with which nature has clothed the skeleton
+framework of the globe. It is difficult to convey by description an idea
+of the desolation of the regions most exposed to the ravages of torrent
+and of flood; and the thousands, who, in these days of travel, are
+whirled by steam near or even through the theatres of these calamities,
+have but rare and imperfect opportunities of observing the destructive
+causes in action. Still more rarely can they compare the past with the
+actual condition of the provinces in question, and trace the progress of
+their conversion from forest-crowned hills, luxuriant pasture grounds,
+and abundant cornfields and vineyards well watered by springs and
+fertilizing rivulets, to bald mountain ridges, rocky declivities, and
+steep earth banks furrowed by deep ravines with beds now dry, now filled
+by torrents of fluid mud and gravel hurrying down to spread themselves
+over the plain, and dooming to everlasting barrenness the once
+productive fields. In traversing such scenes, it is difficult to resist
+the impression that nature pronounced the curse of perpetual sterility
+and desolation upon these sublime but fearful wastes, difficult to
+believe that they were once, and but for the folly of man might still
+be, blessed with all the natural advantages which Providence has
+bestowed upon the most favored climes. But the historical evidence is
+conclusive as to the destructive changes occasioned by the agency of man
+upon the flanks of the Alps, the Apennines, the Pyrenees, and other
+mountain ranges in Central and Southern Europe, and the progress of
+physical deterioration has been so rapid that, in some localities, a
+single generation has witnessed the beginning and the end of the
+melancholy revolution.
+
+It is certain that a desolation, like that which has overwhelmed many
+once beautiful and fertile regions of Europe, awaits an important part
+of the territory of the United States, and of other comparatively new
+countries over which European civilization is now extending its sway,
+unless prompt measures are taken to check the action of destructive
+causes already in operation. It is vain to expect that legislation can
+do anything effectual to arrest the progress of the evil in those
+countries, except so far as the state is still the proprietor of
+extensive forests. Woodlands which have passed into private hands will
+everywhere be managed, in spite of legal restrictions, upon the same
+economical principles as other possessions, and every proprietor will,
+as a general rule, fell his woods, unless he believes that it will be
+for his pecuniary interest to preserve them. Few of the new provinces
+which the last three centuries have brought under the control of the
+European race, would tolerate any interference by the law-making power
+with what they regard as the most sacred of civil rights--the right,
+namely, of every man to do what he will with his own. In the Old World,
+even in France, whose people, of all European nations, love best to be
+governed and are least annoyed by bureaucratic supervision, law has been
+found impotent to prevent the destruction, or wasteful economy, of
+private forests; and in many of the mountainous departments of that
+country, man is at this moment so fast laying waste the face of the
+earth, that the most serious fears are entertained, not only of the
+depopulation of those districts, but of enormous mischiefs to the
+provinces contiguous to them.[214] The only legal provisions from which
+anything is to be hoped, are such as shall make it a matter of private
+advantage to the landholder to spare the trees upon his grounds, and
+promote the growth of the young wood. Something may be done by exempting
+standing forests from taxation, and by imposing taxes on wood felled for
+fuel or for timber, something by premiums or honorary distinctions for
+judicious management of the woods. It would be difficult to induce
+governments, general or local, to make the necessary appropriations for
+such purposes, but there can be no doubt that it would be sound economy
+in the end.
+
+In countries where there exist municipalities endowed with an
+intelligent public spirit, the purchase and control of forests by such
+corporations would often prove advantageous; and in some of the
+provinces of Northern Lombardy, experience has shown that such
+operations may be conducted with great benefit to all the interests
+connected with the proper management of the woods. In Switzerland, on
+the other hand, except in some few cases where woods have been preserved
+as a defence against avalanches, the forests of the communes have been
+productive of little advantage to the public interests, and have very
+generally gone to decay. The rights of pasturage, everywhere destructive
+to trees, combined with toleration of trespasses, have so reduced their
+value, that there is, too often, nothing left that is worth protecting.
+In the canton of Ticino, the peasants have very frequently voted to sell
+the town woods and divide the proceeds among the corporators. The
+sometimes considerable sums thus received are squandered in wild
+revelry, and the sacrifice of the forests brings not even a momentary
+benefit to the proprietors.[215]
+
+It is evidently a matter of the utmost importance that the public, and
+especially land owners, be roused to a sense of the dangers to which the
+indiscriminate clearing of the woods may expose not only future
+generations, but the very soil itself. Fortunately, some of the American
+States, as well as the governments of many European colonies, still
+retain the ownership of great tracts of primitive woodland. The State of
+New York, for example, has, in its northeastern counties, a vast extent
+of territory in which the lumberman has only here and there established
+his camp, and where the forest, though interspersed with permanent
+settlements, robbed of some of its finest pine groves, and often ravaged
+by devastating fires, still covers far the largest proportion of the
+surface. Through this territory, the soil is generally poor, and even
+the new clearings have little of the luxuriance of harvest which
+distinguishes them elsewhere. The value of the land for agricultural
+uses is therefore very small, and few purchases are made for any other
+purpose than to strip the soil of its timber. It has been often proposed
+that the State should declare the remaining forest the inalienable
+property of the commonwealth, but I believe the motive of the suggestion
+has originated rather in poetical than in economical views of the
+subject. Both these classes of considerations have a real worth. It is
+desirable that some large and easily accessible region of American soil
+should remain, as far as possible, in its primitive condition, at once a
+museum for the instruction of the student, a garden for the recreation
+of the lover of nature, and an asylum where indigenous tree, and humble
+plant that loves the shade, and fish and fowl and four-footed beast, may
+dwell and perpetuate their kind, in the enjoyment of such imperfect
+protection as the laws of a people jealous of restraint can afford them.
+The immediate loss to the public treasury from the adoption of this
+policy would be inconsiderable, for these lands are sold at low rates.
+The forest alone, economically managed, would, without injury, and even
+with benefit to its permanence and growth, soon yield a regular income
+larger than the present value of the fee.
+
+The collateral advantages of the preservation of these forests would be
+far greater. Nature threw up those mountains and clothed them with lofty
+woods, that they might serve as a reservoir to supply with perennial
+waters the thousand rivers and rills that are fed by the rains and snows
+of the Adirondacks, and as a screen for the fertile plains of the
+central counties against the chilling blasts of the north wind, which
+meet no other barrier in their sweep from the Arctic pole. The climate
+of Northern New York even now presents greater extremes of temperature
+than that of Southern France. The long continued cold of winter is far
+more intense, the short heats of summer not less fierce than in
+Provence, and hence the preservation of every influence that tends to
+maintain an equilibrium of temperature and humidity is of cardinal
+importance. The felling of the Adirondack woods would ultimately involve
+for Northern and Central New York consequences similar to those which
+have resulted from the laying bare of the southern and western
+declivities of the French Alps and the spurs, ridges, and detached peaks
+in front of them.
+
+It is true that the evils to be apprehended from the clearing of the
+mountains of New York may be less in degree than those which a similar
+cause has produced in Southern France, where the intensity of its action
+has been increased by the inclination of the mountain declivities, and
+by the peculiar geological constitution of the earth. The degradation of
+the soil is, perhaps, not equally promoted by a combination of the same
+circumstances, in any of the American Atlantic States, but still they
+have rapid slopes and loose and friable soils enough to render
+widespread desolation certain, if the further destruction of the woods
+is not soon arrested. The effects of clearing are already perceptible in
+the comparatively unviolated region of which I am speaking. The rivers
+which rise in it flow with diminished currents in dry seasons, and with
+augmented volumes of water after heavy rains. They bring down much
+larger quantities of sediment, and the increasing obstructions to the
+navigation of the Hudson, which are extending themselves down the
+channel in proportion as the fields are encroaching upon the forest,
+give good grounds for the fear of serious injury to the commerce of the
+important towns on the upper waters of that river, unless measures are
+taken to prevent the expansion of "improvements" which have already been
+carried beyond the demands of a wise economy.
+
+I have stated, in a general way, the nature of the evils in question,
+and of the processes by which they are produced; but I shall make their
+precise character and magnitude better understood by presenting some
+descriptive and statistical details of facts of actual occurrence. I
+select for this purpose the southeastern portion of France, not because
+that territory has suffered more severely than some others, but because
+its deterioration is comparatively recent, and has been watched and
+described by very competent and trustworthy observers, whose reports are
+more easily accessible than those published in other countries.[216]
+
+The provinces of Dauphiny, Avignon, and Provence comprise a territory of
+fourteen or fifteen thousand square miles, bounded northwest by the
+Isere, northeast and east by the Alps, south by the Mediterranean, west
+by the Rhone, and extending from 42 deg. to about 45 deg. of north latitude. The
+surface is generally hilly and even mountainous, and several of the
+peaks in Dauphiny rise above the limit of perpetual snow. The climate,
+as compared with that of the United States in the same latitude, is
+extremely mild. Little snow falls, except upon the higher mountain
+ranges, the frosts are light, and the summers long, as might, indeed, be
+inferred from the vegetation; for in the cultivated districts, the vine
+and the fig everywhere flourish, the olive thrives as far north as
+431/2 deg., and upon the coast, grow the orange, the lemon, and the date
+palm. The forest trees, too, are of southern type, umbrella pines,
+various species of evergreen oaks, and many other trees and shrubs of
+persistent broad-leaved foliage, characterizing the landscape.
+
+The rapid slope of the mountains naturally exposed these provinces to
+damage by torrents, and the Romans diminished their injurious effects by
+erecting, in the beds of ravines, barriers of rocks loosely piled up,
+which permitted a slow escape of the water, but compelled it to deposit
+above the dikes the earth and gravel with which it was charged.[217] At
+a later period the Crusaders brought home from Palestine, with much
+other knowledge gathered from the wiser Moslems, the art of securing the
+hillsides and making them productive by terracing and irrigation. The
+forests which covered the mountains secured an abundant flow of springs,
+and the process of clearing the soil went on so slowly that, for
+centuries, neither the want of timber and fuel, nor the other evils
+about to be depicted, were seriously felt. Indeed, throughout the Middle
+Ages, these provinces were well wooded, and famous for the fertility and
+abundance, not only of the low grounds, but of the hills.
+
+Such was the state of things at the close of the fifteenth century. The
+statistics of the seventeenth show that while there had been an increase
+of prosperity and population in Lower Provence, as well as in the
+correspondingly situated parts of the other two provinces I have
+mentioned, there was an alarming decrease both in the wealth and in the
+population of Upper Provence and Dauphiny, although, by the clearing of
+the forests, a great extent of plough land and pasturage had been added
+to the soil before reduced to cultivation. It was found, in fact, that
+the augmented violence of the torrents had swept away, or buried in sand
+and gravel, more land than had been reclaimed by clearing; and the taxes
+computed by fires or habitations underwent several successive reductions
+in consequence of the gradual abandonment of the wasted soil by its
+starving occupants. The growth of the large towns on and near the Rhone
+and the coast, their advance in commerce and industry, and the
+consequently enlarged demand for agricultural products, ought naturally
+to have increased the rural population and the value of their lands; but
+the physical decay of the uplands was such that considerable tracts were
+deserted altogether, and in Upper Provence, the fires which in 1471
+counted 897, were reduced to 747 in 1699, to 728 in 1733, and to 635 in
+1776.
+
+These facts I take from the _La Provence au point de vue des Bois, des
+Torrents et des Inondations_, of Charles de Ribbe, one of the highest
+authorities, and I add further details from the same source.
+
+"Commune of Barles, 1707: Two hills have become connected by land
+slides, and have formed a lake which covers the best part of the soil.
+1746: New slides buried twenty houses composing a village, no trace of
+which is left; more than one third of the land had disappeared.
+
+"Monans, 1724: Deserted by its inhabitants and no longer cultivated.
+
+"Gueydan, 1760: It appears by records that the best grounds have been
+swept off since 1756, and that ravines occupy their place.
+
+"Digne, 1762: The river Bleone has destroyed the most valuable part of
+the territory.
+
+"Malmaison, 1768: The inhabitants have emigrated, all their fields
+having been lost."
+
+In the case of the commune of St. Laurent du Var, it appears that, after
+clearings in the Alps, succeeded by others in the common woods of the
+town, the floods of the torrent Var became more formidable, and had
+already carried off much land as early as 1708. "The clearing continued,
+and more soil was swept away in 1761. In 1762, after another destructive
+inundation, many of the inhabitants emigrated, and in 1765, one half of
+the territory had been laid waste.
+
+"In 1766, the assessor Serraire said to the Assembly: 'As to the damage
+caused by brooks and torrents, it is impossible to deny its extent.
+Upper Provence is in danger of total destruction, and the waters which
+lay it waste threaten also the ruin of the most valuable grounds on the
+plain below. Villages have been almost submerged by torrents which
+formerly had not even names, and large towns are on the point of
+destruction from the same cause.'"
+
+In 1776, Viscount Puget thus reported: "The mere aspect of Upper
+Provence is calculated to appal the patriotic magistrate. One sees only
+lofty mountains, deep valleys with precipitous sides, rivers with broad
+beds and little water, impetuous torrents, which in floods lay waste the
+cultivated land upon their banks and roll huge rocks along their
+channels; steep and parched hillsides, the melancholy consequences of
+indiscriminate clearing; villages whose inhabitants, finding no longer
+the means of subsistence, are emigrating day by day; houses dilapidated
+to huts, and but a miserable remnant of population."
+
+"In a document of the year 1771, the ravages of the torrents were
+compared to the effects of an earthquake, half the soil in many communes
+seeming to have been swallowed up.
+
+"Our mountains," said the administrators of the province of the Lower
+Alps in 1792, "present nothing but a surface of stony tufa; clearing is
+still going on, and the little rivulets are becoming torrents. Many
+communes have lost their harvests, their flocks, and their houses by
+floods. The washing down of the mountains is to be ascribed to the
+clearings and the practice of burning them over."
+
+These complaints, it will be seen, all date before the Revolution, but
+the desolation they describe has since advanced with still swifter
+steps.
+
+Surell--whose valuable work, _Etude sur les Torrents des Hautes Alpes_,
+published in 1841, presents the most appalling picture of the
+desolations of the torrent, and, at the same time, the most careful
+studies of the history and essential character of this great evil--in
+speaking of the valley of Devoluy, on page 152, says: "Everything
+concurs to show that it was anciently wooded. In its peat bogs are
+found buried trunks of trees, monuments of its former vegetation. In the
+framework of old houses, one sees enormous timber, which is no longer to
+be found in the district. Many localities, now completely bare, still
+retain the name of 'wood,' and one of them is called, in old deeds,
+_Comba nigra_ [Black forest or dell], on account of its dense woods.
+These and many other proofs confirm the local traditions which are
+unanimous on this point.
+
+"There, as everywhere in the Upper Alps, the clearings began on the
+flanks of the mountains, and were gradually extended into the valleys
+and then to the highest accessible peaks. Then followed the Revolution,
+and caused the destruction of the remainder of the trees which had thus
+far escaped the woodman's axe."
+
+In a note to this passage, the writer says: "Several persons have told
+me that they had lost flocks of sheep, by straying, in the forests of
+Mont Auroux, which covered the flanks of the mountain from La Cluse to
+Agneres. These declivities are now as bare as the palm of the hand."
+
+The ground upon the steep mountains being once bared of trees, and the
+underwood killed by the grazing of horned cattle, sheep, and goats,
+every depression becomes a watercourse. "Every storm," says Surell, page
+153, "gives rise to a new torrent. Examples of such are shown, which,
+though not yet three years old, have laid waste the finest fields of
+their valleys, and whole villages have narrowly escaped being swept into
+ravines formed in the course of a few hours. Sometimes the flood pours
+in a sheet over the surface, without ravine or even bed, and ruins
+extensive grounds, which are abandoned forever."
+
+I cannot follow Surell in his description and classification of
+torrents, and I must refer the reader to his instructive work for a full
+exposition of the theory of the subject. In order, however, to show what
+a concentration of destructive energies may be effected by felling the
+woods that clothe and support the sides of mountain abysses, I cite his
+description of a valley descending from the Col Isoard, which he calls
+"a complete type of a basin of reception," that is, a gorge which serves
+as a common point of accumulation and discharge for the waters of
+several lateral torrents. "The aspect of the monstrous channel," says
+he, "is frightful. Within a distance of less than three kilometres
+[= one mile and seven eighths English], more than sixty torrents hurl
+into the depths of the gorge the debris torn from its two flanks. The
+smallest of these secondary torrents, if transferred to a fertile
+valley, would be enough to ruin it."
+
+The eminent political economist Blanqui, in a memoir read before the
+Academy of Moral and Political Science on the 25th of November, 1843,
+thus expresses himself: "Important as are the causes of impoverishment
+already described, they are not to be compared to the consequences which
+have followed from the two inveterate evils of the Alpine provinces of
+France, the extension of clearing and the ravages of torrents. * * The
+most important result of this destruction is this: that the agricultural
+capital, or rather the ground itself--which, in a rapidly increasing
+degree, is daily swept away by the waters--is totally lost. Signs of
+unparalleled destitution are visible in all the mountain zone, and the
+solitudes of those districts are assuming an indescribable character of
+sterility and desolation. The gradual destruction of the woods has, in a
+thousand localities, annihilated at once the springs and the fuel.
+Between Grenoble and Briancon in the valley of the Romanche, many
+villages are so destitute of wood that they are reduced to the necessity
+of baking their bread with sun-dried cowdung, and even this they can
+afford to do but once a year. This bread becomes so hard that it can be
+cut only with an axe, and I have myself seen a loaf of bread in
+September, at the kneading of which I was present the January previous.
+
+"Whoever has visited the valley of Barcelonette, those of Embrun, and of
+Verdun, and that Arabia Petraea of the department of the Upper Alps,
+called Devoluy, knows that there is no time to lose, that in fifty years
+from this date France will be separated from Savoy, as Egypt from
+Syria, by a desert."[218]
+
+It deserves to be specially noticed that the district here referred to,
+though now among the most hopelessly waste in France, was very
+productive even down to so late a period as the commencement of the
+French Revolution. Arthur Young, writing in 1789, says: "About
+Barcelonette and in the highest parts of the mountains, the hill
+pastures feed a million of sheep, besides large herds of other cattle;"
+and he adds: "With such a soil, and in such a climate we are not to
+suppose a country barren because it is mountainous. The valleys I have
+visited are, in general, beautiful."[219] He ascribes the same character
+to the provinces of Dauphiny, Provence, and Auvergne, and, though he
+visited, with the eye of an attentive and practised observer, many of
+the scenes since blasted with the wild desolation described by Blanqui,
+the Durance and a part of the course of the Loire are the only streams
+he mentions as inflicting serious injury by their floods. The ravages of
+the torrents had, indeed, as we have seen, commenced earlier in some
+other localities, but we are authorized to infer that they were, in
+Young's time, too limited in range, and relatively too insignificant, to
+require notice in a general view of the provinces where they have now
+ruined so large a proportion of the soil.
+
+But I resume my citations.
+
+"I do not exaggerate," says Blanqui. "When I shall have finished my
+excursion and designated localities by their names, there will rise, I
+am sure, more than one voice from the spots themselves, to attest the
+rigorous exactness of this picture of their wretchedness. I have never
+seen its equal even in the Kabyle villages of the province of
+Constantine; for there you can travel on horseback, and you find grass
+in the spring, whereas in more than fifty communes in the Alps there is
+absolutely nothing.
+
+"The clear, brilliant, Alpine sky of Embrun, of Gap, of Barcelonette,
+and of Digne, which for months is without a cloud, produces droughts
+interrupted only by diluvial rains like those of the tropics. The abuse
+of the right of pasturage and the felling of the woods have stripped the
+soil of all its grass and all its trees, and the scorching sun bakes it
+to the consistence of porphyry. When moistened by the rain, as it has
+neither support nor cohesion, it rolls down to the valleys, sometimes in
+floods resembling black, yellow, or reddish lava, sometimes in streams
+of pebbles, and even huge blocks of stone, which pour down with a
+frightful roar, and in their swift course exhibit the most convulsive
+movements. If you overlook from an eminence one of these landscapes
+furrowed with so many ravines, it presents only images of desolation and
+of death. Vast deposits of flinty pebbles, many feet in thickness, which
+have rolled down and spread far over the plain, surround large trees,
+bury even their tops, and rise above them, leaving to the husbandman no
+longer a ray of hope. One can imagine no sadder spectacle than the deep
+fissures in the flanks of the mountains, which seem to have burst forth
+in eruption to cover the plains with their ruins. These gorges, under
+the influence of the sun which cracks and shivers to fragments the very
+rocks, and of the rain which sweeps them down, penetrate deeper and
+deeper into the heart of the mountain, while the beds of the torrents
+issuing from them are sometimes raised several feet, in a single year,
+by the debris, so that they reach the level of the bridges, which, of
+course, are then carried off. The torrent beds are recognized at a great
+distance, as they issue from the mountains, and they spread themselves
+over the low grounds, in fan-shaped expansions, like a mantle of stone,
+sometimes ten thousand feet wide, rising high at the centre, and curving
+toward the circumference till their lower edges meet the plain.
+
+"Such is their aspect in dry weather. But no tongue can give an adequate
+description of their devastations in one of those sudden floods which
+resemble, in almost none of their phenomena, the action of ordinary
+river water. They are now no longer overflowing brooks, but real seas,
+tumbling down in cataracts, and rolling before them blocks of stone,
+which are hurled forward by the shock of the waves like balls shot out
+by the explosion of gunpowder. Sometimes ridges of pebbles are driven
+down when the transporting torrent does not rise high enough to show
+itself, and then the movement is accompanied with a roar louder than the
+crash of thunder. A furious wind precedes the rushing water and
+announces its approach. Then comes a violent eruption, followed by a
+flow of muddy waves, and after a few hours all returns to the dreary
+silence which at periods of rest marks these abodes of desolation.
+
+"This is but an imperfect sketch of this scourge of the Alps. Its
+devastations are increasing with the progress of clearing, and are every
+day turning a portion of our frontier departments into barren wastes.
+
+"The unfortunate passion for clearing manifested itself at the beginning
+of the French Revolution, and has much increased under the pressure of
+immediate want. It has now reached an extreme point, and must be
+speedily checked, or the last inhabitant will be compelled to retreat
+when the last tree falls.
+
+"The elements of destruction are increasing in violence. Rivers might be
+mentioned whose beds have been raised ten feet in a single year. The
+devastation advances in geometrical progression as the higher slopes are
+bared of their wood, and 'the ruin from above,' to use the words of a
+peasant, 'helps to hasten the desolation below.'
+
+"The Alps of Provence present a terrible aspect. In the more equable
+climate of Northern France, one can form no conception of those parched
+mountain gorges where not even a bush can be found to shelter a bird,
+where, at most, the wanderer sees in summer here and there a withered
+lavender, where all the springs are dried up, and where a dead silence,
+hardly broken by even the hum of an insect, prevails. But if a storm
+bursts forth, masses of water suddenly shoot from the mountain heights
+into the shattered gulfs, waste without irrigating, deluge without
+refreshing the soil they overflow in their swift descent, and leave it
+even more seared than it was from want of moisture. Man at last retires
+from the fearful desert, and I have, the present season, found not a
+living soul in districts where I remember to have enjoyed hospitality
+thirty years ago."
+
+In 1853, ten years after the date of Blanqui's memoir, M. de Bonville,
+prefect of the Lower Alps, addressed to the Government a report in which
+the following passages occur:
+
+"It is certain that the productive mould of the Alps, swept off by the
+increasing violence of that curse of the mountains, the torrents, is
+daily diminishing with fearful rapidity. All our Alps are wholly, or in
+large proportion, bared of wood. Their soil, scorched by the sun of
+Provence, cut up by the hoofs of the sheep, which, not finding on the
+surface the grass they require for their sustenance, scratch the ground
+in search of roots to satisfy their hunger, is periodically washed and
+carried off by melting snows and summer storms.
+
+"I will not dwell on the effects of the torrents. For sixty years they
+have been too often depicted to require to be further discussed, but it
+is important to show that their ravages are daily extending the range of
+devastation. The bed of the Durance, which now in some places exceeds
+2,000 metres [about 6,600 feet, or a mile and a quarter] in width, and,
+at ordinary times, has a current of water less than 10 metres [about 33
+feet] wide, shows something of the extent of the damage.[220] Where, ten
+years ago, there were still woods and cultivated grounds to be seen,
+there is now but a vast torrent: there is not one of our mountains which
+has not at least one torrent, and new ones are daily forming.
+
+"An indirect proof of the diminution of the soil is to be found in the
+depopulation of the country. In 1852, I reported to the General Council
+that, according to the census of that year, the population of the
+department of the Lower Alps had fallen off no less than 5,000 souls in
+the five years between 1846 and 1851.
+
+"Unless prompt and energetic measures are taken, it is easy to fix the
+epoch when the French Alps will be but a desert. The interval between
+1851 and 1856 will show a further decrease of population. In 1862, the
+ministry will announce a continued and progressive reduction in the
+number of acres devoted to agriculture; every year will aggravate the
+evil, and, in a half century, France will count more ruins, and a
+department the less."
+
+Time has verified the predictions of De Bonville. The later census
+returns show a progressive diminution in the population of the
+departments of the Lower Alps, the Isere, the Drome, Ariege, the Upper
+and the Lower Pyrenees, the Lozere, the Ardennes, the Doubs, the Vosges,
+and, in short, in all the provinces formerly remarkable for their
+forests. This diminution is not to be ascribed to a passion for foreign
+emigration, as in Ireland, and in parts of Germany and of Italy; it is
+simply a transfer of population from one part of the empire to another,
+from soils which human folly has rendered uninhabitable, by ruthlessly
+depriving them of their natural advantages and securities, to provinces
+where the face of the earth was so formed by nature as to need no such
+safeguards, and where, consequently, she preserves her outlines in spite
+of the wasteful improvidence of man.[221]
+
+Highly colored as these pictures seem, they are not exaggerated,
+although the hasty tourist through Southern France and Northern Italy,
+finding little in his high road experiences to justify them, might
+suppose them so. The lines of communication by locomotive train and
+diligence lead generally over safer ground, and it is only when they
+ascend the Alpine passes and traverse the mountain chains, that scenes
+somewhat resembling those just described fall under the eye of the
+ordinary traveller. But the extension of the sphere of devastation, by
+the degradation of the mountains and the transportation of their debris,
+is producing analogous effects upon the lower ridges of the Alps and the
+plains which skirt them; and even now one needs but an hour's departure
+from some great thoroughfares to reach sites where the genius of
+destruction revels as wildly as in the most frightful of the abysses
+which Blanqui has painted.[222]
+
+There is one effect of the action of torrents which few travellers on
+the Continent are heedless enough to pass without notice. I refer to the
+elevation of the beds of mountain streams in consequence of the deposit
+of the debris with which they are charged. To prevent the spread of sand
+and gravel over the fields and the deluging overflow of the raging
+waters, the streams are confined by walls and embankments, which are
+gradually built higher and higher as the bed of the torrent is raised,
+so that, to reach a river, you ascend from the fields beside it; and
+sometimes the ordinary level of the stream is above the streets and even
+the roofs of the towns through which it passes.[223]
+
+The traveller who visits the depths of an Alpine ravine, observes the
+length and width of the gorge and the great height and apparent solidity
+of the precipitous walls which bound it, and calculates the mass of rock
+required to fill the vacancy, can hardly believe that the humble
+brooklet which purls at his feet has been the principal agent in
+accomplishing this tremendous erosion. Closer observation will often
+teach him, that the seemingly unbroken rock which overhangs the valley
+is full of cracks and fissures, and really in such a state of
+disintegration that every frost must bring down tons of it. If he
+compute the area of the basin which finds here its only discharge, he
+will perceive that a sudden thaw of the winter's deposit of snow, or one
+of those terrible discharges of rain so common in the Alps, must send
+forth a deluge mighty enough to sweep down the largest masses of gravel
+and of rock.[224] The simple measurement of the cubical contents of the
+semi-circular hillock which he climbed before he entered the gorge, the
+structure and composition of which conclusively show that it must have
+been washed out of this latter by torrential action, will often account
+satisfactorily for the disposal of most of the matter which once filled
+the ravine.
+
+It must further be remembered, that every inch of the violent movement
+of the rocks is accompanied with crushing concussion, or, at least, with
+great abrasion, and, as you follow the deposit along the course of the
+waters which transport it, you find the stones gradually rounding off in
+form, and diminishing in size until they pass successively into gravel,
+sand, impalpable slime.
+
+I do not mean to assert that all the rocky valleys of the Alps have been
+produced by the action of torrents resulting from the destruction of the
+forests. All the greater, and many of the smaller channels, by which
+that chain is drained, owe their origin to higher causes. They are
+primitive fissures, ascribable to disruption in upheaval or other
+geological convulsion, widened and scarped, and often even polished, so
+to speak, by the action of glaciers during the ice period, and but
+little changed in form by running water in later eras.[225]
+
+In these valleys of ancient formation, which extend into the very heart
+of the mountains, the streams, though rapid, have lost the true
+torrential character, if, indeed, they ever possessed it. Their beds
+have become approximately constant, and their walls no longer crumble
+and fall into the waters that wash their bases. The torrent-worn
+ravines, of which I have spoken, are of later date, and belong more
+properly to what may be called the crust of the Alps, consisting of
+loose rocks, of gravel, and of earth, strewed along the surface of the
+great declivities of the central ridge, and accumulated thickly between
+their solid buttresses. But it is on this crust that the mountaineer
+dwells. Here are his forests, here his pastures, and the ravages of the
+torrent both destroy his world, and convert it into a source of
+overwhelming desolation to the plains below.
+
+
+_Transporting Power of Rivers._
+
+An instance that fell under my own observation in 1857, will serve to
+show something of the eroding and transporting power of streams which,
+in these respects, fall incalculably below the torrents of the Alps. In
+a flood of the Ottaquechee, a small river which flows through Woodstock,
+Vermont, a milldam on that stream burst, and the sediment with which the
+pond was filled, estimated after careful measurement at 13,000 cubic
+yards, was carried down by the current. Between this dam and the slack
+water of another, four miles below, the bed of the stream, which is
+composed of pebbles interspersed in a few places with larger stones, is
+about sixty-five feet wide, though, at low water, the breadth of the
+current is considerably less. The sand and fine gravel were smoothly and
+evenly distributed over the bed to a width of fifty-five or sixty feet,
+and for a distance of about two miles, except at two or three
+intervening rapids, filled up all the interstices between the stones,
+covering them to the depth of nine or ten inches, so as to present a
+regularly formed concave channel, lined with sand, and reducing the
+depth of water, in some places, from five or six feet to fifteen or
+eighteen inches. Observing this deposit after the river had subsided and
+become so clear that the bottom could be seen, I supposed that the next
+flood would produce an extraordinary erosion of the banks and some
+permanent changes in the channel of the stream, in consequence of the
+elevation of the bed and the filling up of the spaces between the stones
+through which formerly much water had flowed; but no such result
+followed. The spring freshet of the next year entirely washed out the
+sand its predecessor had deposited, carried it to ponds and still-water
+reaches below, and left the bed of the river almost precisely in its
+former condition, though, of course, with the slight displacement of the
+pebbles which every flood produces in the channels of such streams. The
+pond, though often previously discharged by the breakage of the dam, had
+then been undisturbed for about twenty-five years, and its contents
+consisted almost entirely of sand, the rapidity of the current in floods
+being such that it would let fall little lighter sediment, even above an
+obstruction like a dam. The quantity I have mentioned evidently bears a
+very inconsiderable proportion to the total erosion of the stream
+during that period, because the wash of the banks consists chiefly of
+fine earth rather than of sand, and after the pond was once filled, or
+nearly so, even this material could no longer be deposited in it. The
+fact of the complete removal of the deposit I have described between the
+two dams in a single freshet, shows that, in spite of considerable
+obstruction from roughness of bed, large quantities of sand may be taken
+up and carried off by streams of no great rapidity of inclination; for
+the whole descent of the bed of the river between the two dams--a
+distance of four miles--is but sixty feet, or fifteen feet to the mile.
+
+
+_The Po and its Deposits._
+
+The current of the river Po, for a considerable distance after its
+volume of water is otherwise sufficient for continuous navigation, is
+too rapid for that purpose until near Piacenza, where its velocity
+becomes too much reduced to transport great quantities of mineral
+matter, except in a state of minute division. Its southern affluents
+bring down from the Apennines a large quantity of fine earth from
+various geological formations, while its Alpine tributaries west of the
+Ticino are charged chiefly with rock ground down to sand or
+gravel.[226] The bed of the river has been somewhat elevated by the
+deposits in its channel, though not by any means above the level of the
+adjacent plains as has been so often represented. The dikes, which
+confine the current at high water, at the same time augment its velocity
+and compel it to carry most of its sediment to the Adriatic. It has,
+therefore, raised neither its own channel nor its alluvial shores, as it
+would have done if it had remained unconfined. But, as the surface of
+the water in floods is from six to fifteen feet above the general level
+of its banks, the Po can, at that period, receive no contributions of
+earth from the washing of the fields of Lombardy, and there is no doubt
+that a large proportion of the sediment it now deposits at its mouth
+descended from the Alps in the form of rock, though reduced by the
+grinding action of the waters, in its passage seaward, to the condition
+of fine sand, and often of silt.[227]
+
+We know little of the history of the Po, or of the geography of the
+coast near the point where it enters the Adriatic, at any period more
+than twenty centuries before our own. Still less can we say how much of
+the plains of Lombardy had been formed by its action, combined with
+other causes, before man accelerated its levelling operations by felling
+the first woods on the mountains whence its waters are derived. But we
+know that since the Roman conquest of Northern Italy, its deposits have
+amounted to a quantity which, if recemented into rock, recombined into
+gravel, common earth, and vegetable mould, and restored to the
+situations where eruption or upheaval originally placed, or vegetation
+deposited it, would fill up hundreds of deep ravines in the Alps and
+Apennines, change the plan and profile of their chains, and give their
+southern and northern faces respectively a geographical aspect very
+different from that they now present. Ravenna, forty miles south of the
+principal mouth of the Po, was built like Venice, in a lagoon, and the
+Adriatic still washed its walls at the commencement of the Christian
+era. The mud of the Po has filled up the lagoon, and Ravenna is now four
+miles from the sea. The town of Adria, which lies between the Po and the
+Adige, at the distance of some four or five miles from each, was once a
+harbor famous enough to have given its name to the Adriatic sea, and it
+was still a seaport in the time of Augustus. The combined action of the
+two rivers has so advanced the coast line that Adria is now about
+fourteen miles inland, and, in other places, the deposits made within
+the same period by these and other neighboring streams have a width of
+twenty miles.
+
+What proportion of the earth with which they are charged these rivers
+have borne out into deep water, during the last two thousand years, we
+do not know, but as they still transport enormous quantities, as the
+North Adriatic appears to have shoaled rapidly, and as long islands,
+composed in great part of fluviatile deposits, have formed opposite
+their mouths, it must evidently have been very great. The floods of the
+Po occur but once, or sometimes twice in a year.[228] At other times,
+its waters are comparatively limpid and seem to hold no great amount of
+mud or fine sand in mechanical suspension; but at high water it contains
+a large proportion of solid matter, and according to Lombardini, it
+annually transports to the shores of the Adriatic not less than
+42,760,000 cubic metres, or very nearly 55,000,000 cubic yards, which
+carries the coast line out into the sea at the rate of more than 200
+feet in a year.[229] The depth of the annual deposit is stated at
+eighteen centimetres, or rather more than seven inches, and it would
+cover an area of not much less than ninety square miles with a layer of
+that thickness. The Adige, also, brings every year to the Adriatic many
+million cubic yards of Alpine detritus, and the contributions of the
+Brenta from the same source are far from inconsiderable. The Adriatic,
+however, receives but a small proportion of the soil and rock washed
+away from the Italian slope of the Alps and the northern declivity of
+the Apennines by torrents. Nearly the whole of the debris thus removed
+from the southern face of the Alps between Monte Rosa and the sources of
+the Adda--a length of watershed not less than one hundred and fifty
+miles--is arrested by the still waters of the Lakes Maggiore and Como,
+and some smaller lacustrine reservoirs, and never reaches the sea. The
+Po is not continuously embanked except for the lower half of its course.
+Above Piacenza, therefore, it spreads and deposits sediment over a wide
+surface, and the water withdrawn from it for irrigation at lower points,
+as well as its inundations in the occasional ruptures of its banks,
+carry over the adjacent soil a large amount of slime.
+
+If we add to the estimated annual deposits of the Po at its mouth, the
+earth and sand transported to the sea by the Adige, the Brenta, and
+other less important streams, the prodigious mass of detritus swept into
+Lago Maggiore by the Tosa, the Maggia, and the Ticino, into the lake of
+Como by the Maira and the Adda, into the lake of Garda by its
+affluents, and the yet vaster heaps of pebbles, gravel, and earth
+permanently deposited by the torrents near their points of eruption from
+mountain gorges, or spread over the wide plains at lower levels, we may
+safely assume that we have an aggregate of not less than four times the
+quantity carried to the Adriatic by the Po, or 220,000,000 cubic yards
+of solid matter, abstracted every year from the Italian Alps and the
+Apennines, and removed out of their domain by the force of running
+water.[230]
+
+The present rate of deposit at the mouth of the Po has continued since
+the year 1600, the previous advance of the coast, after the year 1200,
+having been only one third as rapid. The great increase of erosion and
+transport is ascribed by Lombardini chiefly to the destruction of the
+forests in the basin of that river and the valleys, of its tributaries,
+since the beginning of the seventeenth century.[231] We have no data to
+show the rate of deposit in any given century before the year 1200, and
+it doubtless varied according to the progress of population and the
+consequent extension of clearing and cultivation. The transporting power
+of torrents is greatest soon after their formation, because at that time
+their points of delivery are lower, and, of course, their general slope
+and velocity more rapid, than after years of erosion above, and deposit
+below, have depressed the beds of their mountain valleys, and elevated
+the channels of their lower course. Their eroding action also is most
+powerful at the same period, both because their mechanical force is then
+greatest, and because the loose earth and stones of freshly cleared
+forest ground are most easily removed. Many of the Alpine valleys west
+of the Ticino--that of the Dora Baltea for instance--were nearly
+stripped of their forests in the days of the Roman empire, others in the
+Middle Ages, and, of course, there must have been, at different periods
+before the year 1200, epochs when the erosion and transportation of
+solid matter from the Alps and the Apennines were as great as since the
+year 1600.
+
+Upon the whole, we shall not greatly err if we assume that, for a period
+of not less than two thousand years, the walls of the basin of the
+Po--the Italian slope of the Alps, and the northern and northeastern
+declivities of the Apennines--have annually sent down into the Adriatic,
+the lakes, and the plains, not less than 150,000,000 cubic yards of
+earth and disintegrated rock. We have, then, an aggregate of
+300,000,000,000 cubic yards of such material, which, allowing to the
+mountain surface in question an area of 50,000,000,000 square yards,
+would cover the whole to the depth of six yards.[232] There are very
+large portions of this area, where, as we know from ancient
+remains--roads, bridges, and the like--from other direct testimony, and
+from geological considerations, very little degradation has taken place
+within twenty centuries, and hence the quantity to be assigned to
+localities where the destructive causes have been most active is
+increased in proportion.
+
+If this vast mass of pulverized rock and earth were restored to the
+localities from which it was derived, it certainly would not obliterate
+valleys and gorges hollowed out by great geological causes, but it would
+reduce the length and diminish the depth of ravines of later formation,
+modify the inclination of their walls, reclothe with earth many bare
+mountain ridges, essentially change the line of junction between plain
+and mountain, and carry back a long reach of the Adriatic coast many
+miles to the west.[233]
+
+It is, indeed, not to be supposed that all the degradation of the
+mountains is due to the destruction of the forests--that the flanks of
+every Alpine valley in Central Europe below the snow line were once
+covered with earth and green with woods, but there are not many
+particular cases, in which we can, with certainty, or even with strong
+probability, affirm the contrary.
+
+We cannot measure the share which human action has had in augmenting the
+intensity of causes of mountain degradation, but we know that the
+clearing of the woods has, in some cases, produced within two or three
+generations, effects as blasting as those generally ascribed to
+geological convulsions, and has laid waste the face of the earth more
+hopelessly than if it had been buried by a current of lava or a shower
+of volcanic sand. Now torrents are forming every year in the Alps.
+Tradition, written records, and analogy concur to establish the belief
+that the ruin of most of the now desolate valleys in those mountains is
+to be ascribed to the same cause, and authentic descriptions of the
+irresistible force of the torrent show that, aided by frost and heat, it
+is adequate to level Mont Blanc and Monte Rosa themselves, unless new
+upheavals shall maintain their elevation.
+
+It has been contended that all rivers which take their rise in mountains
+originated in torrents. These, it is said, have lowered the summits by
+gradual erosion, and, with the material thus derived, have formed shoals
+in the sea which once beat against the cliffs; then, by successive
+deposits, gradually raised them above the surface, and finally expanded
+them into broad plains traversed by gently flowing streams. If we could
+go back to earlier geological periods, we should find this theory often
+verified, and we cannot fail to see that the torrents go on at the
+present hour, depressing still lower the ridges of the Alps and the
+Apennines, raising still higher the plains of Lombardy and Provence,
+extending the coast still farther into the Adriatic and the
+Mediterranean, reducing the inclination of their own beds and the
+rapidity of their flow, and thus tending to become river-like in
+character.
+
+There are cases where torrents cease their ravages of themselves, in
+consequence of some change in the condition of the basin where they
+originate, or of the face of the mountain at a higher level, while the
+plain or the sea below remains in substantially the same state as
+before. If a torrent rises in a small valley containing no great amount
+of earth and of disintegrated or loose rock, it may, in the course of a
+certain period, wash out all the transportable material, and if the
+valley is then left with solid walls, it will cease to furnish debris to
+be carried down by floods. If, in this state of things, a new channel be
+formed at an elevation above the head of the valley, it may divert a
+part, or even the whole of the rain water and melted snow which would
+otherwise have flowed into it, and the once furious torrent now sinks to
+the rank of a humble and harmless brooklet. "In traversing this
+department," says Surell, "one often sees, at the outlet of a gorge, a
+flattened hillock, with a fan-shaped outline and regular slopes; it is
+the bed of dejection of an ancient torrent. It sometimes requires long
+and careful study to detect the primitive form, masked as it is by
+groves of trees, by cultivated fields, and often by houses, but, when
+examined closely, and from different points of view, its characteristic
+figure manifestly appears, and its true history cannot be mistaken.
+Along the hillock flows a streamlet, issuing from the ravine, and
+quietly watering the fields. This was originally a torrent, and in the
+background may be discovered its mountain basin. Such _extinguished_
+torrents, if I may use the expression, are numerous."[234]
+
+But for the intervention of man and domestic animals, these latter
+beneficent revolutions would occur more frequently, proceed more
+rapidly. The new scarped mountains, the hillocks of debris, the plains
+elevated by sand and gravel spread over them, the shores freshly formed
+by fluviatile deposits, would clothe themselves with shrubs and trees,
+the intensity of the causes of degradation would be diminished, and
+nature would thus regain her ancient equilibrium. But these processes,
+under ordinary circumstances, demand, not years, generations, but
+centuries;[235] and man, who even now finds scarce breathing room on
+this vast globe, cannot retire from the Old World to some yet
+undiscovered continent, and wait for the slow action of such causes to
+replace, by a new creation, the Eden he has wasted.
+
+
+_Mountain Slides._
+
+I have said that the mountainous regions of the Atlantic States of the
+American Union are exposed to similar ravages, and I may add that there
+is, in some cases, reason to apprehend from the same cause even more
+appalling calamities than those which I have yet described. The slide in
+the Notch of the White Mountains, by which the Willey family lost their
+lives, is an instance of the sort I refer to, though I am not able to
+say that in this particular case, the slip of the earth and rock was
+produced by the denudation of the surface. It may have been occasioned
+by this cause, or by the construction of the road through the Notch, the
+excavations for which, perhaps, cut through the buttresses that
+supported the sloping strata above.
+
+Not to speak of the fall of earth when the roots which held it together,
+and the bed of leaves and mould which sheltered it both from
+disintegrating frost and from sudden drenching and dissolution by heavy
+showers, are gone, it is easy to see that, in a climate with severe
+winters, the removal of the forest, and, consequently, of the soil it
+had contributed to form, might cause the displacement and descent of
+great masses of rock. The woods, the vegetable mould, and the soil
+beneath, protect the rocks they cover from the direct action of heat and
+cold, and from the expansion and contraction which accompany them. Most
+rocks, while covered with earth, contain a considerable quantity of
+water.[236] A fragment of rock pervaded with moisture cracks and splits,
+if thrown into a furnace, and sometimes with a loud detonation; and it
+is a familiar observation that the fire, in burning over newly cleared
+lands, breaks up and sometimes almost pulverizes the stones. This effect
+is due partly to the unequal expansion of the stone, partly to the
+action of heat on the water it contains in its pores. The sun, suddenly
+let in upon rock which had been covered with moist earth for centuries,
+produces more or less disintegration in the same way, and the stone is
+also exposed to chemical influences from which it was sheltered before.
+But in the climate of the United States as well as of the Alps, frost is
+a still more powerful agent in breaking up mountain masses. The soil
+that protects the lime and sand stone, the slate and the granite from
+the influence of the sun, also prevents the water which filters into
+their crevices and between their strata from freezing in the hardest
+winters, and the moisture descends, in a liquid form, until it escapes
+in springs, or passes off by deep subterranean channels. But when the
+ridges are laid bare, the water of the autumnal rains fills the minutest
+pores and veins and fissures and lines of separation of the rocks, then
+suddenly freezes, and bursts asunder huge, and apparently solid blocks
+of adamantine stone.[237] Where the strata are inclined at a
+considerable angle, the freezing of a thin film of water over a large
+interstratal area might occasion a slide that should cover miles with
+its ruins; and similar results might be produced by the simple
+hydrostatic pressure of a column of water, admitted by the removal of
+the covering of earth to flow into a crevice faster than it could escape
+through orifices below.
+
+Earth or rather mountain slides, compared to which the catastrophe that
+buried the Willey family in New Hampshire was but a pinch of dust, have
+often occurred in the Swiss Italian, and French Alps. The land slip,
+which overwhelmed and covered to the depth of seventy feet, the town of
+Plurs in the valley of the Maira, on the night of the 4th of September,
+1618, sparing not a soul of a population of 2,430 inhabitants, is one of
+the most memorable of these catastrophes, and the fall of the Rossberg
+or Rufiberg, which destroyed the little town of Goldau in Switzerland,
+and 450 of its people, on the 2d of September, 1806, is almost equally
+celebrated. In 1771, according to Wessely, the mountain peak Piz, near
+Alleghe in the province of Belluno, slipped into the bed of the
+Cordevole, a tributary of the Piave, destroying in its fall three
+hamlets and sixty lives. The rubbish filled the valley for a distance of
+nearly two miles, and, by damming up the waters of the Cordevole, formed
+a lake about three miles long, and a hundred and fifty feet deep, which
+still subsists, though reduced to half its original length by the
+wearing down of its outlet.[238]
+
+On the 14th of February, 1855, the hill of Belmonte, a little below the
+parish of San Stefano, in Tuscany, slid into the valley of the Tiber,
+which consequently flooded the village to the depth of fifty feet, and
+was finally drained off by a tunnel. The mass of debris is stated to
+have been about 3,500 feet long, 1,000 wide, and not less than 600
+high.[239]
+
+Such displacements of earth and rocky strata rise to the magnitude of
+geological convulsions, but they are of so rare occurrence in countries
+still covered by the primitive forest, so common where the mountains
+have been stripped of their native covering, and, in many cases, so
+easily explicable by the drenching of incohesive earth from rain, or the
+free admission of water between the strata of rocks--both of which a
+coating of vegetation would have prevented--that we are justified in
+ascribing them for the most part to the same cause as that to which the
+destructive effects of mountain torrents are chiefly due--the felling of
+the woods.
+
+In nearly every case of this sort the circumstances of which are known,
+the immediate cause of the slip has been, either an earthquake, the
+imbibition of water in large quantities by bare earth, or its
+introduction between or beneath solid strata. If water insinuates itself
+between the strata, it creates a sliding surface, or it may, by its
+expansion in freezing, separate beds of rock, which had been nearly
+continuous before, widely enough to allow the gravitation of the
+superincumbent mass to overcome the resistance afforded by inequalities
+of face and by friction; if it finds its way beneath hard earth or rock
+reposing on clay or other bedding of similar properties, it converts the
+supporting layer into a semi-fluid mud, which opposes no obstacle to the
+sliding of the strata above.
+
+The upper part of the mountain which buried Goldau was composed of a
+hard but brittle conglomerate, called _nagelflue_, resting on an
+unctuous clay, and inclining rapidly toward the village. Much earth
+remained upon the rock, in irregular masses, but the woods had been
+felled, and the water had free access to the surface, and to the
+crevices which sun and frost had already produced in the rock, and of
+course, to the slimy stratum beneath. The whole summer of 1806 had been
+very wet, and an almost incessant deluge of rain had fallen the day
+preceding the catastrophe, as well as on that of its occurrence. All
+conditions then, were favorable to the sliding of the rock, and, in
+obedience to the laws of gravitation, it precipitated itself into the
+valley as soon as its adhesion to the earth beneath it was destroyed by
+the conversion of the latter into a viscous paste. The mass that fell
+measured between two and a half and three miles in length by one
+thousand feet in width, and its average thickness is thought to have
+been about a hundred feet. The highest portion of the mountain was more
+than three thousand feet above the village, and the momentum acquired by
+the rocks and earth in their descent carried huge blocks of stone far up
+the opposite slope of the Rigi.
+
+The Piz, which fell into the Cordevole, rested on a steeply inclined
+stratum of limestone, with a thin layer of calcareous marl intervening,
+which, by long exposure to frost and the infiltration of water, had lost
+its original consistence, and become a loose and slippery mass instead
+of a cohesive and tenacious bed.
+
+
+_Protection against fall of Rocks and Avalanches by Trees._
+
+Forests often subserve a valuable purpose in preventing the fall of
+rocks, by mere mechanical resistance. Trees, as well as herbaceous
+vegetation, grow in the Alps upon declivities of surprising steepness of
+inclination, and the traveller sees both luxuriant grass and flourishing
+woods on slopes at which the soil, in the dry air of lower regions,
+would crumble and fall by the weight of its own particles. When loose
+rocks lie scattered on the face of these declivities, they are held in
+place by the trunks of the trees, and it is very common to observe a
+stone that weighs hundreds of pounds, perhaps even tons, resting against
+a tree which has stopped its progress just as it was beginning to slide
+down to a lower level. When a forest in such a position is cut, these
+blocks lose their support, and a single wet season is enough not only to
+bare the face of a considerable extent of rock, but to cover with earth
+and stone many acres of fertile soil below.[240]
+
+In Switzerland and other snowy and mountainous countries, forests render
+a most important service by preventing the formation and fall of
+destructive avalanches, and in many parts of the Alps exposed to this
+catastrophe, the woods are protected, though too often ineffectually, by
+law. No forest, indeed, could arrest a large avalanche once in motion,
+but the mechanical resistance afforded by the trees prevents their
+formation, both by obstructing the wind, which gives to the dry snow of
+the _Staub-Lawine_, or dust avalanche, its first impulse, and by
+checking the disposition of moist snow to gather itself into what is
+called the _Rutsch-Lawine_, or sliding avalanche. Marschand states that,
+the very first winter after the felling of the trees on the higher part
+of a declivity between Saanen and Gsteig where the snow had never been
+known to slide, an avalanche formed itself in the clearing, thundered
+down the mountain, and overthrew and carried with it a hitherto
+unviolated forest to the amount of nearly a million cubic feet of
+timber.[241] The path once opened down the flanks of the mountain, the
+evil is almost beyond remedy. The snow sometimes carries off the earth
+from the face of the rock, or, if the soil is left, fresh slides every
+winter destroy the young plantations, and the restoration of the wood
+becomes impossible. The track widens with every new avalanche. Dwellings
+and their occupants are buried in the snow, or swept away by the rushing
+mass, or by the furious blasts it occasions through the displacement of
+the air; roads and bridges are destroyed; rivers blocked up, which swell
+till they overflow the valley above, and then, bursting their snowy
+barrier, flood the fields below with all the horrors of a winter
+inundation.[242]
+
+
+_Principal Causes of the Destruction of the Forest._
+
+The needs of agriculture are the most familiar cause of the destruction
+of the forest in new countries; for not only does an increasing
+population demand additional acres to grow the vegetables which feed it
+and its domestic animals, but the slovenly husbandry of the border
+settler soon exhausts the luxuriance of his first fields, and compels
+him to remove his household gods to a fresher soil. With growing
+numbers, too, come the many arts for which wood is the material. The
+demands of the near and the distant market for this product excite the
+cupidity of the hardy forester, and a few years of that wild industry of
+which Springer's "Forest Life and Forest Trees" so vividly depicts the
+dangers and the triumphs, suffice to rob the most inaccessible glens of
+their fairest ornaments. The value of timber increases with its
+dimensions in almost geometrical proportion, and the tallest, most
+vigorous, and most symmetrical trees fall the first sacrifice. This is a
+fortunate circumstance for the remainder of the wood; for the impatient
+lumberman contents himself with felling a few of the best trees, and
+then hurries on to take his tithe of still virgin groves.
+
+The unparalleled facilities for internal navigation, afforded by the
+numerous rivers of the present and former British colonial possessions
+in North America, have proved very fatal to the forests of that
+continent. Quebec has become a centre for a lumber trade, which, in the
+bulk of its material, and, consequently, in the tonnage required for its
+transportation, rivals the commerce of the greatest European cities.
+Immense rafts are collected at Quebec from the great Lakes, from the
+Ottawa, and from all the other tributaries which unite to swell the
+current of the St. Lawrence and help it to struggle against its mighty
+tides.[243] Ships, of burden formerly undreamed of, have been built to
+convey the timber to the markets of Europe, and during the summer months
+the St. Lawrence is almost as crowded with vessels as the Thames.[244]
+Of late, Chicago, in Illinois, has been one of the greatest lumber as
+well as grain depots of the United States, and it receives and
+distributes contributions from all the forests in the States washed by
+Lake Michigan, as well as from some more distant points.
+
+The operations of the lumberman involve other dangers to the woods
+besides the loss of the trees felled by him. The narrow clearings around
+his _shanties_[245] form openings which let in the wind, and thus
+sometimes occasion the overthrow of thousands of trees, the fall of
+which dams up small streams, and creates bogs by the spreading of the
+waters, while the decaying trunks facilitate the multiplication of the
+insects which breed in dead wood, and are, some of them, injurious to
+living trees. The escape and spread of camp fires, however, is the most
+devastating of all the causes of destruction that find their origin in
+the operations of the lumberman. The proportion of trees fit for
+industrial uses is small in all primitive woods. Only these fall before
+the forester's axe, but the fire destroys, indiscriminately, every age
+and every species of tree.[246] While, then, without much injury to the
+younger growths, the native forest will bear several "cuttings over" in
+a generation--for the increasing value of lumber brings into use, every
+four or five years, a quality of timber which had been before rejected
+as unmarketable--a fire may render the declivity of a mountain
+unproductive for a century.[247]
+
+
+_American Forest Trees._
+
+The remaining forests of the Northern States and of Canada no longer
+boast the mighty pines which almost rivalled the gigantic Sequoia of
+California; and the growth of the larger forest trees is so slow, after
+they have attained to a certain size, that if every pine and oak were
+spared for two centuries, the largest now standing would not reach the
+stature of hundreds recorded to have been cut within two or three
+generations.[248] Dr. Williams, who wrote about sixty years ago, states
+the following as the dimensions of "such trees as are esteemed large
+ones of their kind in that part of America" [Vermont], qualifying his
+account with the remark that his measurements "do not denote the
+greatest which nature has produced of their particular species, but the
+greatest which are to be found in most of our towns."
+
+ Diameter. Height.
+
+ Pine, 6 feet, 247 feet.
+ Maple, 5 " 9 inches, }
+ Buttonwood, 5 " 6 " }
+ Elm, 5 " }
+ Hemlock, 4 " 9 " }
+ Oak, 4 " } From 100 to 200 feet.
+ Basswood, 4 " }
+ Ash, 4 " }
+ Birch, 4 " }
+
+He adds a note saying that a white pine was cut in Dunstable, New
+Hampshire, in the year 1736, the diameter of which was seven feet and
+eight inches. Dr. Dwight says that a fallen pine in Connecticut was
+found to measure two hundred and forty-seven feet in height, and adds:
+"A few years since, such trees were in great numbers along the northern
+parts of Connecticut River." In another letter, he speaks of the white
+pine as "frequently six feet in diameter, and two hundred and fifty feet
+in height," and states that a pine had been cut in Lancaster, New
+Hampshire, which measured two hundred and sixty-four feet. Emerson wrote
+in 1846: "Fifty years ago, several trees growing on rather dry land in
+Blandford, Massachusetts, measured, after they were felled, two hundred
+and twenty-three feet. All these trees are surpassed by a pine felled at
+Hanover, New Hampshire, about a hundred years ago, and described as
+measuring two hundred and seventy-four feet.[249]
+
+These descriptions, it will be noticed, apply to trees cut from sixty to
+one hundred years since. Persons, whom observation has rendered familiar
+with the present character of the American forest, will be struck with
+the smallness of the diameter which Dr. Williams and Dr. Dwight ascribe
+to trees of such extraordinary height. Individuals of the several
+species mentioned in Dr. Williams's table, are now hardly to be found in
+the same climate, exceeding one half or at most two thirds of the height
+which he assigns to them; but, except in the case of the oak and the
+pine, the diameter stated by him would not be thought very extraordinary
+in trees of far less height, now standing. Even in the species I have
+excepted, those diameters, with half the heights of Dr. Williams, might
+perhaps be paralleled at the present time; and many elms, transplanted,
+at a diameter of six inches, within the memory of persons still living,
+measure six, and sometimes even seven feet through. For this change
+in the growth of forest trees there are two reasons: the one is,
+that the great commercial value of the pine and the oak have
+caused the destruction of all the best--that is, the tallest and
+straightest--specimens of both; the other, that the thinning of the
+woods by the axe of the lumberman has allowed the access of light and
+heat and air to trees of humbler worth and lower stature, which have
+survived their more towering brethren. These, consequently, have been
+able to expand their crowns and swell their stems to a degree not
+possible so long as they were overshadowed and stifled by the lordly oak
+and pine. While, therefore, the New England forester must search long
+before he finds a pine
+
+ fit to be the mast
+ Of some great ammiral,
+
+beeches and elms and birches, as sturdy as the mightiest of their
+progenitors, are still no rarity.[250]
+
+Another evil, sometimes of serious magnitude, which attends the
+operations of the lumberman, is the injury to the banks of rivers from
+the practice of floating. I do not here allude to rafts, which, being
+under the control of those who navigate them, may be so guided as to
+avoid damage to the shore, but to masts, logs, and other pieces of
+timber singly intrusted to the streams, to be conveyed by their currents
+to sawmill ponds, or to convenient places for collecting them into
+rafts. The lumbermen usually haul the timber to the banks of the rivers
+in the winter, and when the spring floods swell the streams and break up
+the ice, they roll the logs into the water, leaving them to float down
+to their destination. If the transporting stream is too small to furnish
+a sufficient channel for this rude navigation, it is sometimes dammed
+up, and the timber collected in the pond thus formed above the dam. When
+the pond is full, a sluice is opened, or the dam is blown up or
+otherwise suddenly broken, and the whole mass of lumber above it is
+hurried down with the rolling flood. Both of these modes of proceeding
+expose the banks of the rivers employed as channels of flotation to
+abrasion,[251] and in some of the American States it has been found
+necessary to protect, by special legislation, the lands through which
+they flow from the serious injury sometimes received through the
+practices I have described.[252]
+
+
+_Special Causes of the Destruction of European Woods._
+
+The causes of forest waste thus far enumerated are more or less common
+to both continents; but in Europe extensive woods have, at different
+periods, been deliberately destroyed by fire or the axe, because they
+afforded a retreat to enemies, robbers, and outlaws, and this practice
+is said to have been resorted to in the Mediterranean provinces of
+France as recently as the time of Napoleon I.[253] The severe and even
+sanguinary legislation, by which some of the governments of mediaeval
+Europe, as well as of earlier ages, protected the woods, was dictated by
+a love of the chase, or the fear of a scarcity of fuel and timber. The
+laws of almost every European state more or less adequately secure the
+permanence of the forest; and I believe Spain is the only European land
+which has not made some public provision for the protection and
+restoration of the woods--the only country whose people systematically
+war upon the garden of God.[254]
+
+
+_Royal Forests and Game Laws._
+
+The French authors I have quoted, as well as many other writers of the
+same nation, refer to the French Revolution as having given a new
+impulse to destructive causes which were already threatening the total
+extermination of the woods.[255] The general crusade against the
+forests, which accompanied that important event, is to be ascribed, in a
+considerable degree, to political resentments. The forest codes of the
+mediaeval kings, and the local "coutumes" of feudalism contained many
+severe and even inhuman provisions, adopted rather for the preservation
+of game than from any enlightened views of the more important functions
+of the woods. Ordericus Vitalis informs us that William the Conqueror
+destroyed sixty parishes, and drove out their inhabitants, in order that
+he might turn their lands into a forest,[256] to be reserved as a
+hunting ground for himself and his posterity, and he punished with death
+the killing of a deer, wild boar, or even a hare. His successor, William
+Rufus, according to the _Histoire des Ducs de Normandie et des Rois
+d'Angleterre_, p. 67, "was hunting one day in a new forest, which he had
+caused to be made out of eighteen parishes that he had destroyed, when,
+by mischance, he was killed by an arrow wherewith Tyreus de Rois [Sir
+Walter Tyrell] thought to slay a beast, but missed the beast, and slew
+the king, who was beyond it. And in this very same forest, his brother
+Richard ran so hard against a tree that he died of it. And men commonly
+said that these things were because they had so laid waste and taken the
+said parishes."
+
+These barbarous acts, as Bonnemere observes,[257] were simply the
+transfer of the customs of the French kings, of their vassals, and even
+of inferior gentlemen, to conquered England. "The death of a hare," says
+our author, "was a hanging matter, the murder of a plover a capital
+crime. Death was inflicted on those who spread nets for pigeons;
+wretches who had drawn a bow upon a stag were to be tied to the animal
+alive; and among the seigniors it was a standing excuse for having
+killed game on forbidden ground, that they aimed at a serf." The feudal
+lords enforced these codes with unrelenting rigor, and not unfrequently
+took the law into their own hands. In the time of Louis IX, according to
+William of Nangis, "three noble children, born in Flanders, who were
+sojourning at the abbey of St. Nicholas in the Wood, to learn the speech
+of France, went out into the forest of the abbey, with their bows and
+iron-headed arrows, to disport them in shooting hares, chased the game,
+which they had started in the wood of the abbey, into the forest of
+Enguerrand, lord of Coucy, and were taken by the sergeants which kept
+the wood. When the fell and pitiless Sir Enguerrand knew this, he had
+the children straightway hanged without any manner of trial."[258] The
+matter being brought to the notice of good King Louis, Sir Enguerrand
+was summoned to appear, and, finally, after many feudal shifts and
+dilatory pleas, brought to trial before Louis himself and a special
+council. Notwithstanding the opposition of the other seigniors, who, it
+is needless to say, spared no efforts to save a peer, probably not a
+greater criminal than themselves, the king was much inclined to inflict
+the punishment of death on the proud baron. "If he believed," said he,
+"that our Lord would be as well content with hanging as with pardoning,
+he would hang Sir Enguerrand in spite of all his barons;" but noble and
+clerical interests unfortunately prevailed. The king was persuaded to
+inflict a milder retribution, and the murderer was condemned to pay ten
+thousand livres in coin, and to "build for the souls of the three
+children two chapels wherein mass should be said every day."[259] The
+hope of shortening the purgatorial term of the young persons, by the
+religious rites to be celebrated in the chapels, was doubtless the
+consideration which operated most powerfully on the mind of the king;
+and Europe lost a great example for the sake of a mass.
+
+The desolation and depopulation, resulting from the extension of the
+forest and the enforcement of the game laws, induced several of the
+French kings to consent to some relaxation of the severity of these
+latter. Francis I, however, revived their barbarous provisions, and,
+according to Bonnemere, even so good a monarch as Henry IV reenacted
+them, and "signed the sentence of death upon peasants guilty of having
+defended their fields against devastation by wild beasts." "A fine of
+twenty livres," he continues, "was imposed on every one shooting at
+pigeons, which, at that time, swooped down by thousands upon the
+new-sown fields and devoured the seed. But let us count even this a
+progress, for we have seen that the murder of a pigeon had been a
+capital crime."[260]
+
+Not only were the slightest trespasses on the forest domain--the cutting
+of an oxgoad, for instance--severely punished, but game animals were
+still sacred when they had wandered from their native precincts and were
+ravaging the fields of the peasantry. A herd of deer or of wild boars
+often consumed or trod down a harvest of grain, the sole hope of the
+year for a whole family; and the simple driving out of such animals from
+this costly pasturage brought dire vengeance on the head of the rustic,
+who had endeavored to save his children's bread from their voracity. "At
+all times," says Paul Louis Courier, speaking in the name of the
+peasants of Chambord, in the "Simple Discours," "the game has made war
+upon us. Paris was blockaded eight hundred years by the deer, and its
+environs, now so rich, so fertile, did not yield bread enough to support
+the gamekeepers."[261]
+
+In the popular mind, the forest was associated with all the abuses of
+feudalism, and the evils the peasantry had suffered from the legislation
+which protected both it and the game it sheltered, blinded them to the
+still greater physical mischiefs which its destruction was to entail
+upon them. No longer protected by law, the crown forests and those of
+the great lords were attacked with relentless fury, unscrupulously
+plundered and wantonly laid waste, and even the rights of property in
+small private woods were no longer respected.[262] Various absurd
+theories, some of which are not even yet exploded, were propagated with
+regard to the economical advantages of converting the forest into
+pasture and ploughland, its injurious effects upon climate, health,
+facility of internal communication, and the like. Thus resentful memory
+of the wrongs associated with the forest, popular ignorance, and the
+cupidity of speculators cunning enough to turn these circumstances to
+profitable account, combined to hasten the sacrifice of the remaining
+woods, and a waste was produced which hundreds of years and millions of
+treasure will hardly repair.
+
+
+_Small Forest Plants, and Vitality of Seed._
+
+Another function of the woods to which I have barely alluded deserves a
+fuller notice than can be bestowed upon it in a treatise the scope of
+which is purely economical. The forest is the native habitat of a large
+number of humbler plants, to the growth and perpetuation of which its
+shade, its humidity, and its vegetable mould appear to be indispensable
+necessities.[263] We cannot positively say that the felling of the
+woods in a given vegetable province would involve the final extinction
+of the smaller plants which are found only within their precincts. Some
+of these, though not naturally propagating themselves in the open
+ground, may perhaps germinate and grow under artificial stimulation and
+protection, and finally become hardy enough to maintain an independent
+existence in very different circumstances from those which at present
+seem essential to their life.
+
+Besides this, although the accounts of the growth of seeds, which have
+lain for ages in the ashy dryness of Egyptian catacombs, are to be
+received with great caution, or, more probably, to be rejected
+altogether, yet their vitality seems almost imperishable while they
+remain in the situations in which nature deposits them. When a forest
+old enough to have witnessed the mysteries of the Druids is felled,
+trees of other species spring up in its place; and when they, in their
+turn, fall before the axe, sometimes even as soon as they have spread
+their protecting shade over the surface, the germs which their
+predecessors had shed years, perhaps centuries before, sprout up, and in
+due time, if not choked by other trees belonging to a later stage in the
+order of natural succession, restore again the original wood. In these
+cases, the seeds of the new crop may often have been brought by the
+wind, by birds, by quadrupeds, or by other causes; but, in many
+instances, this explanation is not probable.
+
+When newly cleared ground is burnt over in the United States, the ashes
+are hardly cold before they are covered with a crop of fire weed, a tall
+herbaceous plant, very seldom seen growing under other circumstances,
+and often not to be found for a distance of many miles from the
+clearing. Its seeds, whether the fruit of an ancient vegetation or newly
+sown by winds or birds, require either a quickening by a heat which
+raises to a certain high point the temperature of the stratum where they
+lie buried, or a special pabulum furnished only by the combustion of the
+vegetable remains that cover the ground in the woods. Earth brought up
+from wells or other excavations soon produces a harvest of plants often
+very unlike those of the local flora.
+
+Moritz Wagner, as quoted by Wittwer,[264] remarks in his description of
+Mount Ararat: "A singular phenomenon to which my guide drew my attention
+is the appearance of several plants on the earth-heaps left by the last
+catastrophe [an earthquake], which grow nowhere else on the mountain,
+and had never been observed in this region before. The seeds of these
+plants were probably brought by birds, and found in the loose, clayey
+soil remaining from the streams of mud, the conditions of growth which
+the other soil of the mountain refused them." This is probable enough,
+but it is hardly less so that the flowing mud brought them up to the
+influence of air and sun, from depths where a previous convulsion had
+buried them ages before. Seeds of small sylvan plants, too deeply buried
+by successive layers of forest foliage and the mould resulting from its
+decomposition to be reached by the plough when the trees are gone and
+the ground brought under cultivation, may, if a wiser posterity replants
+the wood which sheltered their parent stems, germinate and grow, after
+lying for generations in a state of suspended animation.
+
+Darwin says: "In Staffordshire, on the estate of a relation, where I had
+ample means of investigation, there was a large and extremely barren
+heath, which had never been touched by the hand of man, but several
+hundred acres of exactly the same nature had been enclosed twenty-five
+years previously and planted with Scotch fir. The change in the native
+vegetation of the planted part of the heath was most remarkable--more
+than is generally seen in passing from one quite different soil to
+another; not only the proportional numbers of the heath plants were
+wholly changed, but _twelve species_ of plants (not counting grasses and
+sedges) flourished in the plantation which could not be found on the
+heath."[265] Had the author informed us that these twelve plants
+belonged to a species whose seeds enter into the nutriment of the birds
+which appeared with the young wood, we could easily account for their
+presence in the soil; but he says distinctly that the birds were of
+insectivorous species, and it therefore seems more probable that the
+seeds had been deposited when an ancient forest protected the growth of
+the plants which bore them, and that they sprang up to new life when a
+return of favorable conditions awaked them from a sleep of centuries.
+Darwin indeed says that the heath "had never been touched by the hand
+of man." Perhaps not, after it became a heath; but what evidence is
+there to control the general presumption that this heath was preceded by
+a forest, in whose shade the vegetables which dropped the seeds in
+question might have grown?[266]
+
+Although, therefore, the destruction of a wood and the reclaiming of the
+soil to agricultural uses suppose the death of its smaller dependent
+flora, these revolutions do not exclude the possibility of its
+resurrection. In a practical view of the subject, however, we must admit
+that when the woodman fells a tree he sacrifices the colony of humbler
+growths which had vegetated under its protection. Some wood plants are
+known to possess valuable medicinal properties, and experiment may show
+that the number of these is greater than we now suppose. Few of them,
+however, have any other economical value than that of furnishing a
+slender pasturage to cattle allowed to roam in the woods; and even this
+small advantage is far more than compensated by the mischief done to the
+young trees by browsing animals. Upon the whole, the importance of this
+class of vegetables, as physic or as food, is not such as to furnish a
+very telling popular argument for the conservation of the forest as a
+necessary means of their perpetuation. More potent remedial agents may
+supply their place in the _materia medica_, and an acre of grass land
+yields more nutriment for cattle than a range of a hundred acres of
+forest. But he whose sympathies with nature have taught him to feel that
+there is a fellowship between all God's creatures; to love the brilliant
+ore better than the dull ingot, iodic silver and crystallized red copper
+better than the shillings and the pennies forged from them by the
+coiner's cunning; a venerable oak tree than the brandy cask whose staves
+are split out from its heart wood; a bed of anemones, hepaticas, or wood
+violets than the leeks and onions which he may grow on the soil they
+have enriched and in the air they made fragrant--he who has enjoyed that
+special training of the heart and intellect which can be acquired only
+in the unviolated sanctuaries of nature, "where man is distant, but God
+is near"--will not rashly assert his right to extirpate a tribe of
+harmless vegetables, barely because their products neither tickle his
+palate nor fill his pocket; and his regret at the dwindling area of the
+forest solitude will be augmented by the reflection that the nurselings
+of the woodland perish with the pines, the oaks, and the beeches that
+sheltered them.[267]
+
+Although, as I have said, birds do not frequent the deeper recesses of
+the wood,[268] yet a very large proportion of them build their nests in
+trees, and find in their foliage and branches a secure retreat from the
+inclemencies of the seasons and the pursuit of the reptiles and
+quadrupeds which prey upon them. The borders of the forests are vocal
+with song; and when the gray morning calls the creeping things of the
+earth out of their night cells, it summons from the neighboring wood
+legions of their winged enemies, which swoop down upon the fields to
+save man's harvests by devouring the destroying worm, and surprising the
+lagging beetle in his tardy retreat to the dark cover where he lurks
+through the hours of daylight.
+
+The insects most injurious to rural industry do not multiply in or near
+the woods. The locust, which ravages the East with its voracious armies,
+is bred in vast open plains which admit the full heat of the sun to
+hasten the hatching of the eggs, gather no moisture to destroy them, and
+harbor no bird to feed upon the larvae.[269] It is only since the felling
+of the forests of Asia Minor and Cyrene that the locust has become so
+fearfully destructive in those countries; and the grasshopper, which now
+threatens to be almost as great a pest to the agriculture of some North
+American soils, breeds in seriously injurious numbers only where a wide
+extent of surface is bare of woods.
+
+
+_Utility of the Forest._
+
+In most parts of Europe, the woods are already so nearly extirpated that
+the mere protection of those which now exist is by no means an adequate
+remedy for the evils resulting from the want of them; and besides, as I
+have already said, abundant experience has shown that no legislation can
+secure the permanence of the forest in private hands. Enlightened
+individuals in most European states, governments in others, have made
+very extensive plantations,[270] and France has now set herself
+energetically at work to restore the woods in the southern provinces,
+and thereby to prevent the utter depopulation and waste with which that
+once fertile soil and delicious climate are threatened.
+
+The objects of the restoration of the forest are as multifarious as the
+motives that have led to its destruction, and as the evils which that
+destruction has occasioned. It is hoped that the planting of the
+mountains will diminish the frequency and violence of river inundations,
+prevent the formation of torrents, mitigate the extremes of atmospheric
+temperature, humidity, and precipitation, restore dried-up springs,
+rivulets, and sources of irrigation, shelter the fields from chilling
+and from parching winds, prevent the spread of miasmatic effluvia, and,
+finally, furnish an inexhaustible and self-renewing supply of a material
+indispensable to so many purposes of domestic comfort, to the successful
+exercise of every art of peace, every destructive energy of war.[271]
+
+But our enumeration of the uses of trees is not yet complete. Besides
+the influence of the forest, in mountain ranges, as a means of
+preventing the scooping out of ravines and the accumulations of water
+which fill them, trees subserve a valuable purpose, in lower positions,
+as barriers against the spread of floods and of the material they
+transport with them; but this will be more appropriately considered in
+the chapter on the waters; and another very important use of trees, that
+of fixing movable sand-dunes, and reclaiming them to profitable
+cultivation, will be pointed out in the chapter on the sands.
+
+The vast extension of railroads, of manufactures and the mechanical
+arts, of military armaments, and especially of the commercial fleets and
+navies of Christendom within the present century, has greatly augmented
+the demand for wood,[272] and, but for improvements in metallurgy which
+have facilitated the substitution of iron for that material, the last
+twenty-five years would almost have stripped Europe of her only
+remaining trees fit for such uses.[273] The walnut trees alone felled in
+Europe within two years to furnish the armies of America with
+gunstocks, would form a forest of no inconsiderable extent.[274]
+
+
+_The Forests of Europe._
+
+Mirabeau estimated the forests of France in 1750 at seventeen millions
+of hectares [42,000,000 acres]; in 1860 they were reduced to eight
+millions [19,769,000 acres]. This would be at the rate of 82,000
+hectares [202,600 acres] per year. Troy, from whose valuable pamphlet,
+_Etude sur le Reboisement des Montagnes_, I take these statistical
+details, supposes that Mirabeau's statement may have been an extravagant
+one, but it still remains certain that the waste has been enormous; for
+it is known that, in some departments, that of Ariege, for instance,
+clearing has gone on during the last half century at the rate of three
+thousand acres a year,[275] and in all parts of the empire trees have
+been felled faster than they have grown. The total area of France,
+excluding Savoy, is about one hundred and thirty-one millions of acres.
+The extent of forest supposed by Mirabeau would be about thirty-two per
+cent. of the whole territory.[276] In a country and a climate where the
+conservative influences of the forest are so necessary as in France,
+trees must cover a large surface and be grouped in large masses, in
+order to discharge to the best advantage the various functions assigned
+to them by nature. The consumption of wood is rapidly increasing in that
+empire, and a large part of its territory is mountainous, sterile, and
+otherwise such in character or situation that it can be more profitably
+devoted to the growth of wood than to any agricultural use. Hence it is
+evident that the proportion of forest in 1750, taking even Mirabeau's
+large estimate, was not very much too great for permanent maintenance,
+though doubtless the distribution was so unequal that it would have been
+sound policy to fell the woods and clear land in some provinces, while
+large forests should have been planted in others.[277] During the
+period in question, France neither exported manufactured wood or rough
+timber, nor derived important collateral advantages of any sort from the
+destruction of her forests. She is consequently impoverished and
+crippled to the extent of the difference between what she actually
+possesses of wooded surface and what she ought to have retained.
+
+Italy and Spain are bared of trees in a greater degree than France, and
+even Russia, which we habitually consider as substantially a forest
+country, is beginning to suffer seriously for want of wood. Jourdier, as
+quoted by Clave, observes: "Instead of a vast territory with immense
+forests, which we expect to meet, one sees only scattered groves thinned
+by the wind or by the axe of the _moujik_, grounds cut over and more or
+less recently cleared for cultivation. There is probably not a single
+district in Russia which has not to deplore the ravages of man or of
+fire, those two great enemies of Muscovite sylviculture. This is so
+true, that clear-sighted men already foresee a crisis which will become
+terrible, unless the discovery of great deposits of some new
+combustible, as pit coal or anthracite, shall diminish its evils."[278]
+
+Germany, from character of surface and climate, and from the attention
+which has long been paid in all the German States to sylviculture, is,
+taken as a whole, in a far better condition in this respect than its
+more southern neighbors; but in the Alpine provinces of Bavaria and
+Austria, the same improvidence which marks the rural economy of the
+corresponding districts of Switzerland, Italy, and France, is producing
+effects hardly less disastrous. As an instance of the scarcity of fuel
+in some parts of the territory of Bavaria, where, not long since, wood
+abounded, I may mention the fact that the water of salt springs is, in
+some instances, conveyed to the distance of sixty miles, in iron pipes,
+to reach a supply of fuel for boiling it down.[279]
+
+
+_Forests of the United States and Canada._
+
+The vast forests of the United States and Canada cannot long resist the
+improvident habits of the backwoodsman and the increased demand for
+lumber. According to the census of the former country for 1860, which
+gives returns of the "sawed and planed lumber" alone, timber for
+framing and for a vast variety of mechanical purposes being omitted
+altogether, the value of the former material prepared for market in the
+United States was, in 1850, $58,521,976; in 1860, $95,912,286. The
+quantity of unsawed lumber is not likely to have increased in the same
+proportion, because comparatively little is exported in that condition,
+and because masonry is fast taking the place of carpentry in building,
+and stone, brick, and iron are used instead of timber more largely than
+they were ten years ago. Still a much greater quantity of unsawed lumber
+must have been marketed in 1860 than in 1850. It must further be
+admitted that the price of lumber rose considerably between those dates,
+and consequently that the increase in quantity is not to be measured by
+the increase in pecuniary value. Perhaps this rise of prices may even be
+sufficient to make the entire difference between the value of "sawed and
+planed lumber" produced in the ten years in question by the six New
+England States (21 per cent.), and the six Middle States (15 per cent.);
+but the amount produced by the Western and by the Southern States had
+doubled, and that returned from the Pacific States and Territories had
+trebled in value in the same interval, so that there was certainly, in
+those States, a large increase in the actual quantity prepared for sale.
+
+I greatly doubt whether any one of the American States, except, perhaps,
+Oregon, has, at this moment, more woodland than it ought permanently to
+preserve, though, no doubt, a different distribution of the forests in
+all of them might be highly advantageous. It is a great misfortune to
+the American Union that the State Governments have so generally disposed
+of their original domain to private citizens. It is true that public
+property is not sufficiently respected in the United States; and it is
+also true that, within the memory of almost every man of mature age,
+timber was of so little value in that country, that the owners of
+private woodlands submitted, almost without complaint, to what would be
+regarded elsewhere as very aggravated trespasses upon them.[280] Under
+such circumstances, it is difficult to protect the forest, whether it
+belong to the state or to individuals. Property of this kind would be
+subject to much plunder, as well as to frequent damage by fire. The
+destruction from these causes would, indeed, considerably lessen, but
+would not wholly annihilate the climatic and geographical influences of
+the forest, or ruinously diminish its value as a regular source of
+supply of fuel and timber. For prevention of the evils upon which I have
+so long dwelt, the American people must look to the diffusion of general
+intelligence on this subject, and to the enlightened self interest, for
+which they are remarkable, not to the action of their local or general
+legislatures. Even in France, government has moved with too slow and
+hesitating a pace, and preventive measures do not yet compensate
+destructive causes. The judicious remarks of Troy on this point may well
+be applied to other countries than France, other measures of public
+policy than the preservation of the woods. "To move softly," says he,
+"is to commit the most dangerous, the most unpardonable of imprudences;
+it diminishes the prestige of authority; it furnishes a triumph to the
+sneerer and the incredulous; it strengthens opposition and encourages
+resistance; it ruins the administration in the opinion of the people,
+weakens its power and depresses its courage."[281]
+
+
+_The Economy of the Forest._
+
+The legislation of European states upon sylviculture, and the practice
+of that art, divide themselves into two great branches--the preservation
+of existing forests, and the creation of new. From the long operation of
+causes already set forth, what is understood in America and other new
+countries by the "primitive forest," no longer exists in the territories
+which were the seats of ancient civilization and empire, except upon a
+small scale, and in remote and almost inaccessible glens quite out of
+the reach of ordinary observation. The oldest European woods, indeed,
+are native, that is, sprung from self-sown seed, or from the roots of
+trees which have been felled for human purposes; but their growth has
+been controlled, in a variety of ways, by man and by domestic animals,
+and they always present more or less of an artificial character and
+arrangement. Both they and planted forests, which, though certainly not
+few, are of recent date in Europe, demand, as well for protection as for
+promotion of growth, a treatment different in some respects from that
+which would be suited to the character and wants of the virgin wood.
+
+On this latter branch of the subject, experience and observation have
+not yet collected a sufficient stock of facts to serve for the
+construction of a complete system of sylviculture; but the management of
+the forest as it exists in France--the different zones and climates of
+which country present many points of analogy with those of the United
+States and some of the British colonies--has been carefully studied, and
+several manuals of practice have been prepared for the foresters of that
+empire. I believe the best of these is the _Cours Elementaire de Culture
+des Bois cree a l'Ecole Forestiere de Nancy, par M. Lorentz, complete,
+et publie par A. Parade_, with a supplement under the title of _Cours
+d'Amenagement des Forets, par Henri Nanquette_. The _Etudes sur
+l'Economie Forestiere, par Jules Clave_, which I have often quoted,
+presents a great number of interesting views on this subject, and well
+deserves to be translated for the use of the English and American
+reader; but it is not designed as a practical guide, and it does not
+profess to be sufficiently specific in its details to serve that
+purpose. Notwithstanding the difference of conditions between the
+aboriginal and the trained forest, the judicious observer who aims at
+the preservation of the former will reap much instruction from the
+treatises I have cited, and I believe he will be convinced that the
+sooner a natural wood is brought into the state of an artificially
+regulated one, the better it is for all the multiplied interests which
+depend on the wise administration of this branch of public
+economy.[282]
+
+One consideration bearing on this subject has received less attention
+than it merits, because most persons interested in such questions have
+not opportunities for the comparison I refer to. I mean the great
+general superiority of cultivated timber to that of strictly spontaneous
+growth. I say _general_ superiority, because there are exceptions to the
+rule. The white pine, _Pinus strobus_, for instance, and other trees of
+similar character and uses, require, for their perfect growth, a density
+of forest vegetation around them, which protects them from too much
+agitation by wind, and from the persistence of the lateral branches
+which fill the wood with knots. A pine which has grown under those
+conditions possesses a tall, straight stem, admirably fitted for masts
+and spars, and, at the same time, its wood is almost wholly free from
+knots, is regular in annular structure, soft and uniform in texture,
+and, consequently, superior to almost all other timber for joinery. If,
+while a large pine is spared, the broad-leaved or other smaller trees
+around it are felled, the swaying of the tree from the action of the
+wind mechanically produces separations between the layers of annual
+growth, and greatly diminishes the value of the timber.
+
+The same defect is often observed in pines which, from some accident of
+growth, have much overtopped their fellows in the virgin forest. The
+white pine, growing in the fields, or in open glades in the woods, is
+totally different from the true forest tree, both in general aspect and
+in quality of wood. Its stem is much shorter, its top less tapering, its
+foliage denser and more inclined to gather into tufts, its branches more
+numerous and of larger diameter, its wood shows much more distinctly the
+divisions of annual growth, is of coarser grain, harder and more
+difficult to work into mitre joints. Intermixed with the most valuable
+pines in the American forests, are met many trees of the character I
+have just described. The lumbermen call them "saplings," and generally
+regard them as different in species from the true white pine, but
+botanists are unable to establish a distinction between them, and as
+they agree in almost all respects with trees grown in the open grounds
+from known white-pine seedlings, I believe their peculiar character is
+due to unfavorable circumstances in their early growth. The pine, then,
+is an exception to the general rule as to the inferiority of the forest
+to the open-ground tree. The pasture oak and pasture beech, on the
+contrary, are well known to produce far better timber than those grown
+in the woods, and there are few trees to which the remark is not equally
+applicable.[283]
+
+Another advantage of the artificially regulated forest is, that it
+admits of such grading of the ground as to favor the retention or
+discharge of water at will, while the facilities it affords for
+selecting and duly proportioning, as well as properly spacing, the trees
+which compose it, are too obvious to require to be more than hinted at.
+In conducting these operations, we must have a diligent eye to the
+requirements of nature, and must remember that a wood is not an
+arbitrary assemblage of trees to be selected and disposed according to
+the caprice of its owner. "A forest," says Clave, "is not, as is often
+supposed, a simple collection of trees succeeding each other in long
+perspective, without bond of union, and capable of isolation from each
+other; it is, on the contrary, a whole, the different parts of which are
+interdependent upon each other, and it constitutes, so to speak, a true
+individuality. Every forest has a special character, determined by the
+form of the surface it grows upon, the kinds of trees that compose it,
+and the manner in which they are grouped."[284]
+
+
+_European and American Trees compared._
+
+The woods of North America are strikingly distinguished from those of
+Europe by the vastly greater variety of species they contain. According
+to Clave, there are in "France and in most parts of Europe" only about
+twenty forest trees, five or six of which are spike-leaved and resinous,
+the remainder broad-leaved."[285] Our author, however, doubtless means
+genera, though he uses the word _especes_. Rossmaessler enumerates
+fifty-seven species of forest trees as found in Germany, but some of
+these are mere shrubs, some are fruit and properly garden trees, and
+some others are only varieties of familiar species. The valuable manual
+of Parade describes about the same number, including, however, two of
+American origin--the locust, _Robinia pseudacacia_, and the Weymouth or
+white pine, _Pinus strobus_--and the cedar of Lebanon from Asia, though
+it is indigenous in Algeria also. We may then safely say that Europe
+does not possess above forty or fifty trees of such economical value as
+to be worth the special care of the forester, while the oak alone
+numbers not less than thirty species in the United States,[286] and some
+other North American genera are almost equally diversified.[287]
+
+Few European trees, except those bearing edible fruit, have been
+naturalized in the United States, while the American forest flora has
+made large contributions to that of Europe. It is a very poor taste
+which has led to the substitution of the less picturesque European for
+the graceful and majestic American elm, in some public grounds in the
+United States. On the other hand, the European mountain ash--which in
+beauty and healthfulness of growth is superior to our own--the horse
+chestnut, and the abele, or silver poplar, are valuable additions to the
+ornamental trees of North America. The Swiss arve or zirbelkiefer,
+_Pinus cembra_, which yields a well-flavored edible seed and furnishes
+excellent wood for carving, the umbrella pine which also bears a seed
+agreeable to the taste, and which, from the color of its foliage and the
+beautiful form of its dome-like crown, is among the most elegant of
+trees, the white birch of Central Europe, with its pendulous branches
+almost rivalling those of the weeping willow in length, flexibility, and
+gracefulness of fall, and, especially, the "cypresse funerall," might be
+introduced into the United States with great advantage to the landscape.
+The European beech and chestnut furnish timber of far better quality
+than that of their American congeners. The fruit of the European
+chestnut, though inferior to the American in flavor, is larger, and is
+an important article of diet among the French and Italian peasantry. The
+walnut of Europe, though not equal to some of the American species in
+beauty of growth or of wood, or to others in strength and elasticity of
+fibre, is valuable for its timber and its oil.[288] The maritime pine,
+which has proved of such immense use in fixing drifting sands in France,
+may perhaps be better adapted to this purpose than any of the pines of
+the New World, and it is of great importance for its turpentine, resin,
+and tar. The epicea, or common fir, _Abies picea_, _Abies excelsa_,
+_Picea excelsa_, abundant in the mountains of France and the contiguous
+country, is known for its product, Burgundy pitch, and, as it flourishes
+in a greater variety of soil and climate than almost any other
+spike-leaved tree, it might be well worth transplantation.[289] The cork
+oak has been introduced into the United States, I believe, and would
+undoubtedly thrive in the Southern section of the Union.[290]
+
+In the walnut, the chestnut, the cork oak, the mulberry, the olive, the
+orange, the lemon, the fig, and the multitude of other trees which, by
+their fruit, or by other products, yield an annual revenue, nature has
+provided Southern Europe with a partial compensation for the loss of
+the native forest. It is true that these trees, planted as most of them
+are at such distances as to admit of cultivation, or of the growth of
+grass among them, are but an inadequate substitute for the thick and
+shady wood; but they perform to a certain extent the same offices of
+absorption and transpiration, they shade the surface of the ground, they
+serve to break the force of the wind, and on many a steep declivity,
+many a bleak and barren hillside, the chestnut binds the soil together
+with its roots, and prevents tons of earth and gravel from washing down
+upon the fields and the gardens. Fruit trees are not wanting, certainly,
+north of the Alps. The apple, the pear, and the prune are important in
+the economy both of man and of nature, but they are far less numerous in
+Switzerland and Northern France than are the trees I have mentioned in
+Southern Europe, both because they are in general less remunerative, and
+because the climate, in higher latitudes, does not permit the free
+introduction of shade trees into grounds occupied for agricultural
+purposes.[291]
+
+The multitude of species, intermixed as they are in their spontaneous
+growth, gives the American forest landscape a variety of aspect not
+often seen in the woods of Europe, and the gorgeous tints, which nature
+repeats from the dying dolphin to paint the falling leaf of the American
+maples, oaks, and ash trees, clothe the hillsides and fringe the
+watercourses with a rainbow splendor of foliage, unsurpassed by the
+brightest groupings of the tropical flora. It must be admitted, however,
+that both the northern and the southern declivities of the Alps exhibit
+a nearer approximation to this rich and multifarious coloring of
+autumnal vegetation than most American travellers in Europe are willing
+to allow; and, besides, the small deciduous shrubs which often carpet
+the forest glades of these mountains are dyed with a ruddy and orange
+glow, which, in the distant landscape, is no mean substitute for the
+scarlet and crimson and gold and amber of the transatlantic woodland.
+
+No American evergreen known to me resembles the umbrella pine
+sufficiently to be a fair object of comparison with it.[292] A cedar,
+very common above the Highlands on the Hudson, is extremely like the
+cypress, straight, slender, with erect, compressed ramification, and
+feathered to the ground, but its foliage is neither so dark nor so
+dense, the tree does not attain the majestic height of the cypress, nor
+has it the lithe flexibility of that tree. In mere shape, the Lombardy
+poplar nearly resembles this latter, but it is almost a profanation to
+compare the two, especially when they are agitated by the wind; for
+under such circumstances, the one is the most majestic, the other the
+most ungraceful, or--if I may apply such an expression to anything but
+human affectation of movement--the most awkward of trees. The poplar
+trembles before the blast, flutters, struggles wildly, dishevels its
+foliage, gropes around with its feeble branches, and hisses as in
+impotent passion. The cypress gathers its limbs still more closely to
+its stem, bows a gracious salute rather than an humble obeisance to the
+tempest, bends to the wind with an elasticity that assures you of its
+prompt return to its regal attitude, and sends from its thick leaflets a
+murmur like the roar of the far-off ocean.
+
+The cypress and the umbrella pine are not merely conventional types of
+the Italian landscape. They are essential elements in a field of rural
+beauty which can be seen in perfection only in the basin of the
+Mediterranean, and they are as characteristic of this class of scenery
+as the date palm is of the oases of the desert. There is, however, this
+difference: a single cypress or pine is often enough to shed beauty over
+a wide area; the palm is a social tree, and its beauty is not so much
+that of the individual as of the group. The frequency of the cypress and
+the pine--combined with the fact that the other trees of Southern Europe
+which most interest a stranger from the north, the orange and the lemon,
+the cork oak, the ilex, the myrtle, and the laurel, are evergreens--goes
+far to explain the beauty of the winter scenery of Italy. Indeed it is
+only in the winter that a tourist who confines himself to wheel
+carriages and high roads can acquire any notion of the face of the
+earth, and form any proper geographical image of that country. At other
+seasons, not high walls only, but equally impervious hedges, and now,
+unhappily, acacias thickly planted along the railway routes, confine the
+view so completely, that the arch of a tunnel, or a night cap over the
+traveller's eyes, is scarcely a more effectual obstacle to the
+gratification of his curiosity.[293]
+
+
+_Sylviculture._
+
+The art, or, as the Continental foresters call it, the science of
+sylviculture has been so little pursued in England and America, that its
+nomenclature has not been introduced into the English vocabulary, and I
+shall not be able to describe its processes with technical propriety of
+language, without occasionally borrowing a word from the forest
+literature of France and Germany. A full discussion of the methods of
+sylviculture would, indeed, be out of place in a work like the present,
+but the almost total want of conveniently accessible means of
+information on the subject, in English-speaking countries, will justify
+me in presenting it with somewhat more of detail than would otherwise be
+pertinent.
+
+The two best known methods are those distinguished as the _taillis_,
+copse or coppice treatment,[294] and the _futaie_, for which I find no
+English equivalent, but which may not inappropriately be called the
+_full-growth_ system. A _taillis_, copse, or coppice, is a wood composed
+of shoots from the roots of trees previously cut for fuel and timber.
+The shoots are thinned out from time to time, and finally cut, either
+after a fixed number of years, or after the young trees have attained to
+certain dimensions, their roots being then left to send out a new
+progeny as before. This is the cheapest method of management, and
+therefore the best wherever the price of labor and of capital bears a
+high proportion to that of land and of timber; but it is essentially a
+wasteful economy. If the woodland is, in the first place, completely cut
+over, as is found most convenient in practice, the young shoots have
+neither the shade nor the protection from wind so important to forest
+growth, and their progress is comparatively slow, while, at the same
+time, the thick clumps they form choke the seedlings that may have
+sprouted near them. If domestic animals of any species are allowed to
+roam in the wood, they browse upon the terminal buds and the tender
+branches, thereby stunting, if they do not kill, the young trees, and
+depriving them of all beauty and vigor of growth. The evergreens, once
+cut, do not shoot up again,[295] and the mixed character of the
+forest--in many respects an important advantage, if not an indispensable
+condition of growth--is lost;[296] and besides this, large wood of any
+species cannot be grown in this method, because trees which shoot from
+decaying stumps and their dying roots, become hollow or otherwise
+unsound before they acquire their full dimensions. A more fatal
+objection still, is, that the roots of trees will not bear more than two
+or three, or at most four cuttings of their shoots before their vitality
+is exhausted, and the wood can then be restored only by replanting
+entirely. The period of cutting coppices varies in Europe from fifteen
+to forty years, according to soil, species, and rapidity of growth.
+
+In the _futaie_, or full-growth system, the trees are allowed to stand
+as long as they continue in healthy and vigorous growth. This is a
+shorter period than would be at first supposed, when we consider the
+advanced age and great dimensions to which, under favorable
+circumstances, many forest trees attain in temperate climates. But, as
+every observing person familiar with the natural forest is aware, these
+are exceptional cases, just as are instances of great longevity or of
+gigantic stature among men. Able vegetable physiologists have maintained
+that the tree, like most reptiles, has no natural limit of life or of
+growth, and that the only reason why our oaks and our pines do not reach
+the age of twenty centuries and the height of a hundred fathoms, is,
+that in the multitude of accidents to which they are exposed, the
+chances of their attaining to such a length of years and to such
+dimensions of growth are a million to one against them. But another
+explanation of this fact is possible. In trees affected by no
+discoverable external cause of death, decay begins at the topmost
+branches, which seem to wither and die for want of nutriment. The
+mysterious force by which the sap is carried from the roots to the
+utmost twigs, cannot be conceived to be unlimited in power, and it is
+probable that it differs in different species, so that while it may
+suffice to raise the fluid to the height of five hundred feet in the
+sequoia, it may not be able to carry it beyond one hundred and fifty in
+the oak. The limit may be different, too, in different trees of the same
+species, not from defective organization in those of inferior growth,
+but from more or less favorable conditions of soil, nourishment, and
+exposure. Whenever a tree attains to the limit beyond which its
+circulating fluids cannot rise, we may suppose that decay begins, and
+death follows, from the same causes which bring about the same results
+in animals of limited size--such, for example, as the interruption of
+functions essential to life, in consequence of the clogging up of ducts
+by matter assimilable in the stage of growth, but no longer so when
+increment has ceased.
+
+In the natural woods, we observe that, though, among the myriads of
+trees which grow upon a square mile, there are several vegetable giants,
+yet the great majority of them begin to decay long before they have
+attained their maximum of stature, and this seems to be still more
+emphatically true of the artificial forest. In France, according to
+Clave, "oaks, in a suitable soil, may stand, without exhibiting any sign
+of decay, for two or three hundred years; the pines hardly exceed one
+hundred and twenty, and the soft or white woods [_bois blancs_], in wet
+soils, languish and die before reaching the fiftieth year."[297] These
+ages are certainly below the average of those of American forest trees,
+and are greatly exceeded in very numerous well-attested instances of
+isolated trees in Europe.
+
+The former mode of treating the futaie, called the garden system, was to
+cut the trees individually as they arrived at maturity, but, in the best
+regulated forests, this practice has been abandoned for the German
+method, which embraces not only the securing of the largest immediate
+profit, but the replanting of the forest, and the care of the young
+growth. This is effected in the case of a forest, whether natural or
+artificial, which is to be subjected to regular management, by three
+operations. The first of these consists in felling about one third of
+the wood, in such way as to leave convenient spaces for the growth of
+young trees. The remaining two-thirds are relied upon to replant the
+vacancies, by natural sowing, which they seldom or never fail to do. The
+seedlings are watched, are thinned out when too dense, the ill formed
+and sickly, as well as those of inferior value, and the shrubs and
+thorns which might otherwise choke or too closely shade them, are pulled
+up. When they have attained sufficient strength and development of
+foliage to bear or to require more light and air, the second step is
+taken, by removing a suitable proportion of the old trees which had been
+spared at the first cutting; and when, finally, they are hardened enough
+to bear frost and sun without other protection than that which they
+mutually give to each other, the remainder of the original forest is
+felled, and the wood now consists wholly of young and vigorous trees.
+This result is obtained after about twenty years. At convenient periods
+afterward, the unhealthy stocks and those injured by wind or other
+accidents are removed, and in some instances the growth of the remainder
+is promoted by irrigation or by fertilizing applications.[298] When the
+forest is approaching to maturity, the original processes already
+described are repeated; and as, in different parts of an extensive
+forest, they would take place in different zones, it would afford
+indefinitely an annual crop of firewood and timber.
+
+The duties of the forester do not end here. It sometimes happens that
+the glades left by felling the older trees are not sufficiently seeded,
+or that the species, or _essences_, as the French oddly call them, are
+not duly proportioned in the new crop. In this case, seed must be
+artificially sown, or young trees planted in the vacancies.
+
+One of the most important rules in the administration of the forest is
+the absolute exclusion of domestic quadrupeds from every wood which is
+not destined to be cleared. No growth of young trees is possible where
+cattle are admitted to pasture at any season of the year, though they
+are undoubtedly most destructive while trees are in leaf.[299]
+
+It is often necessary to take measures for the protection of young trees
+against the rabbit, the mole, and other rodent quadrupeds, and of older
+ones against the damage done by the larvae of insects hatched upon the
+surface or in the tissues of the bark, or even in the wood itself. The
+much greater liability of the artificial than of the natural forest to
+injury from this cause is perhaps the only point in which the
+superiority of the former to the latter is not as marked as that of any
+domesticated vegetable to its wild representative. But the better
+quality of the wood and the much more rapid growth of the trained and
+regulated forest are abundant compensations for the loss thus
+occasioned, and the progress of entomological science will, perhaps,
+suggest new methods of preventing the ravages of insects. Thus far,
+however, the collection and destruction of the eggs, by simple but
+expensive means, has proved the only effectual remedy.[300]
+
+It is common in Europe to permit the removal of the fallen leaves and
+fragments of bark and branches with which the forest soil is covered,
+and sometimes the cutting of the lower twigs of evergreens. The leaves
+and twigs are principally used as litter for cattle, and finally as
+manure, the bark and wind-fallen branches as fuel. By long usage,
+sometimes by express grant, this privilege has become a vested right of
+the population in the neighborhood of many public, and even large
+private forests; but it is generally regarded as a serious evil. To
+remove the leaves and fallen twigs is to withdraw much of the pabulum
+upon which the tree was destined to feed. The small branches and leaves
+are the parts of the tree which yield the largest proportion of ashes on
+combustion, and of course they supply a great amount of nutriment for
+the young shoots. "A cubic foot of twigs," says Vaupell, "yields four
+times as much ashes as a cubic foot of stem wood. * * For every hundred
+weight of dried leaves carried off from a beech forest, we sacrifice a
+hundred and sixty cubic feet of wood. The leaves and the mosses are a
+substitute, not only for manure, but for ploughing. The carbonic acid
+given out by decaying leaves, when taken up by water, serves to
+dissolve the mineral constituents of the soil, and is particularly
+active in disintegrating feldspar and the clay derived from its
+decomposition. * * * The leaves belong to the soil. Without them it
+cannot preserve its fertility, and cannot furnish nutriment to the
+beech. The trees languish, produce seed incapable of germination, and
+the spontaneous self-sowing, which is an indispensable element in the
+best systems of sylviculture, fails altogether in the bared and
+impoverished soil."[301]
+
+Besides these evils, the removal of the leaves deprives the soil of that
+spongy character which gives it such immense value as a reservoir of
+moisture and a regulator of the flow of springs; and, finally, it
+exposes the surface roots to the drying influence of sun and wind, to
+accidental mechanical injury from the tread of animals or men, and, in
+cold climates, to the destructive effects of frost.
+
+The annual lopping and trimming of trees for fuel, so common in Europe,
+is fatal to the higher uses of the forest, but where small groves are
+made, or rows of trees planted, for no other purpose than to secure a
+supply of firewood, or to serve as supports for the vine, it is often
+very advantageous. The willows, and many other trees, bear polling for a
+long series of years without apparent diminution of growth of branches,
+and though certainly a polled, or, to use an old English word, a
+doddered tree, is in general a melancholy object, yet it must be
+admitted that the aspect of some species--the American locust, _Robinia
+pseudacacia_, for instance--when young, is improved by this
+process.[302]
+
+I have spoken of the needs of agriculture as a principal cause of the
+destruction of the forest, and of domestic cattle as particularly
+injurious to the growth of young trees. But these animals affect the
+forest, indirectly, in a still more important way, because the extent of
+cleared ground required for agricultural use depends very much on the
+number and kinds of the cattle bred. We have seen, in a former chapter,
+that, in the United States, the domestic quadrupeds amount to more than
+a hundred millions, or three times the number of the human population of
+the Union. In many of the Western States, the swine subsist more or less
+on acorns, nuts, and other products of the woods, and the prairies, or
+natural meadows of the Mississippi valley, yield a large amount of food
+for beast, as well as for man. With these exceptions, all this vast army
+of quadrupeds is fed wholly on grass, grain, pulse, and roots grown on
+soil reclaimed from the forest by European settlers. It is true that the
+flesh of domestic quadrupeds enters very largely into the aliment of the
+American people, and greatly reduces the quantity of vegetable nutriment
+which they would otherwise consume, so that a smaller amount of
+agricultural product is required for immediate human food, and, of
+course, a smaller extent of cleared land is needed for the growth of
+that product, than if no domestic animals existed. But the flesh of the
+horse, the ass, and the mule is not consumed by man, and the sheep is
+reared rather for its fleece than for food. Besides this, the ground
+required to produce the grass and grain consumed in rearing and
+fattening a grazing quadruped, would yield a far larger amount of
+nutriment, if devoted to the growing of breadstuffs, than is furnished
+by his flesh; and, upon the whole, whatever advantages may be reaped
+from the breeding of domestic cattle, it is plain that the cleared land
+devoted to their sustenance in the originally wooded part of the United
+States, after deducting a quantity sufficient to produce an amount of
+aliment equal to their flesh, still greatly exceeds that cultivated for
+vegetables, directly consumed by the people of the same regions; or, to
+express a nearly equivalent idea in other words, the meadow and the
+pasture, taken together, much exceed the plough land.[303]
+
+In fertile countries, like the United States, the foreign demand for
+animal and vegetable aliment, for cotton, and for tobacco, much enlarges
+the sphere of agricultural operations, and, of course, prompts further
+encroachments upon the forest. The commerce in these articles,
+therefore, constitutes in America a special cause of the destruction of
+the woods, which does not exist in the numerous states of the Old World
+that derive the raw material of their mechanical industry from distant
+lands, and import many articles of vegetable food or luxury which their
+own climates cannot advantageously produce.
+
+The growth of arboreal vegetation is so slow that, though he who buries
+an acorn may hope to see it shoot up to a miniature resemblance of the
+majestic tree which shall shade his remote descendants, yet the longest
+life hardly embraces the seedtime and the harvest of a forest. The
+planter of a wood must be actuated by higher motives than those of an
+investment the profits of which consist in direct pecuniary gain to
+himself or even to his posterity; for if, in rare cases, an artificial
+forest may, in two or three generations, more than repay its original
+cost, still, in general, the value of its timber will not return the
+capital expended and the interest accrued.[304] But when we consider the
+immense collateral advantages derived from the presence, the terrible
+evils necessarily resulting from the destruction of the forest, both the
+preservation of existing woods, and the far more costly extension of
+them where they have been unduly reduced, are among the most obvious of
+the duties which this age owes to those that are to come after it.
+Especially is this obligation incumbent upon Americans. No civilized
+people profits so largely from the toils and sacrifices of its immediate
+predecessors as they; no generations have ever sown so liberally, and,
+in their own persons, reaped so scanty a return, as the pioneers of
+Anglo-American social life. We can repay our debt to our noble
+forefathers only by a like magnanimity, by a like self-forgetting care
+for the moral and material interests of our own posterity.
+
+
+_Instability of American Life._
+
+All human institutions, associate arrangements, modes of life, have
+their characteristic imperfections. The natural, perhaps the necessary
+defect of ours, is their instability, their want of fixedness, not in
+form only, but even in spirit. The face of physical nature in the United
+States shares this incessant fluctuation, and the landscape is as
+variable as the habits of the population. It is time for some abatement
+in the restless love of change which characterizes us, and makes us
+almost a nomade rather than a sedentary people.[305] We have now felled
+forest enough everywhere, in many districts far too much. Let us restore
+this one element of material life to its normal proportions, and devise
+means for maintaining the permanence of its relations to the fields, the
+meadows, and the pastures, to the rain and the dews of heaven, to the
+springs and rivulets with which it waters the earth. The establishment
+of an approximately fixed ratio between the two most broadly
+characterized distinctions of rural surface--woodland and plough
+land--would involve a certain persistence of character in all the
+branches of industry, all the occupations and habits of life, which
+depend upon or are immediately connected with either, without implying a
+rigidity that should exclude flexibility of accommodation to the many
+changes of external circumstance which human wisdom can neither prevent
+nor foresee, and would thus help us to become, more emphatically, a
+well-ordered and stable commonwealth, and, not less conspicuously, a
+people of progress.
+
+ NOTE on word _watershed_, omitted on p. 257.--Sir John F. W.
+ Herschel (_Physical Geography_, 137, and elsewhere) spells this
+ word _water-sched_, because he considers it a translation, or
+ rather an adoption of the German "Wasser-scheide, separation of
+ the waters, not water-_shed_, the slope _down which_ the waters
+ run," As a point of historical etymology, it is probable that the
+ word in question was suggested to those who first used it by the
+ German _Wasserscheide_; but the spelling _water-sched_, proposed
+ by Herschel, is objectionable, both because _sch_ is a
+ combination of letters wholly unknown to modern English
+ orthography and properly representing no sound recognized in
+ English orthoepy, and for the still better reason that
+ _watershed_, in the sense of _division-of-the-waters_, has a
+ legitimate English etymology.
+
+ The Anglo-Saxon _sceadan_ meant both to separate or divide, and
+ to shade or shelter. It is the root of the English verbs _to
+ shed_ and _to shade_, and in the former meaning is the A. S.
+ equivalent of the German verb _scheiden_.
+
+ _Shed_ in Old English had the meaning _to separate_ or
+ _distinguish_. It is so used in the _Owl and the Nightingale_, v.
+ 197. Palsgrave (_Lesclarcissement, etc._, p. 717) defines _I
+ shede_, I departe thinges asonder; and the word still means _to
+ divide_ in several English local dialects. Hence, _watershed_,
+ the division or separation of the waters, is good English both in
+ sense and spelling.
+
+
+
+
+CHAPTER IV.
+
+THE WATERS.
+
+LAND ARTIFICIALLY WON FROM THE WATERS: _a_, EXCLUSION OF THE SEA BY
+DIKING; _b_, DRAINING OF LAKES AND MARSHES; _c_, GEOGRAPHICAL INFLUENCE
+OF SUCH OPERATIONS--LOWERING OF LAKES--MOUNTAIN LAKES--CLIMATIC EFFECTS
+OF DRAINING LAKES AND MARSHES--GEOGRAPHICAL AND CLIMATIC EFFECTS OF
+AQUEDUCTS, RESERVOIRS, AND CANALS--SURFACE AND UNDERDRAINING, AND THEIR
+CLIMATIC AND GEOGRAPHICAL EFFECTS--IRRIGATION AND ITS CLIMATIC AND
+GEOGRAPHICAL EFFECTS.
+
+INUNDATIONS AND TORRENTS: _a_, RIVER EMBANKMENTS; _b_, FLOODS OF THE
+ARDECHE; _c_, CRUSHING FORCE OF TORRENTS; _d_, INUNDATIONS OF 1856 IN
+FRANCE; _e_, REMEDIES AGAINST INUNDATIONS--CONSEQUENCES IF THE NILE HAD
+BEEN CONFINED BY LATERAL DIKES.
+
+IMPROVEMENTS IN THE VAL DI CHIANA--IMPROVEMENTS IN THE TUSCAN
+MAREMME--OBSTRUCTION OF RIVER MOUTHS--SUBTERRANEAN WATERS--ARTESIAN
+WELLS--ARTIFICIAL SPRINGS--ECONOMIZING PRECIPITATION.
+
+
+_Land artificially won from the Waters._
+
+Man, as we have seen, has done much to revolutionize the solid surface
+of the globe, and to change the distribution and proportions, if not the
+essential character, of the organisms which inhabit the land and even
+the waters. Besides the influence thus exerted upon the life which
+peoples the sea, his action upon the land has involved a certain amount
+of indirect encroachment upon the territorial jurisdiction of the ocean.
+So far as he has increased the erosion of running waters by the
+destruction of the forest, he has promoted the deposit of solid matter
+in the sea, thus reducing its depth, advancing the coast line, and
+diminishing the area covered by the waters. He has gone beyond this, and
+invaded the realm of the ocean by constructing within its borders
+wharves, piers, lighthouses, breakwaters, fortresses, and other
+facilities for his commercial and military operations; and in some
+countries he has permanently rescued from tidal overflow, and even from
+the very bed of the deep, tracts of ground extensive enough to
+constitute valuable additions to his agricultural domain. The quantity
+of soil gained from the sea by these different modes of acquisition is,
+indeed, too inconsiderable to form an appreciable element in the
+comparison of the general proportion between the two great forms of
+terrestrial surface, land and water; but the results of such operations,
+considered in their physical and their moral bearings, are sufficiently
+important to entitle them to special notice in every comprehensive view
+of the relations between man and nature.
+
+There are cases, as on the western shores of the Baltic, where, in
+consequence of the secular elevation of the coast, the sea appears to be
+retiring; others, where, from the slow sinking of the land, it seems to
+be advancing. These movements depend upon geological causes wholly out
+of our reach, and man can neither advance nor retard them. There are
+also cases where similar apparent effects are produced by local oceanic
+currents, by river deposit or erosion, by tidal action, or by the
+influence of the wind upon the waves and the sands of the sea beach. A
+regular current may drift suspended earth and seaweed along a coast
+until they are caught by an eddy and finally deposited out of the reach
+of further disturbance, or it may scoop out the bed of the sea and
+undermine promontories and headlands; a powerful river, as the wind
+changes the direction of its flow at its outlet, may wash away shores
+and sandbanks at one point to deposit their material at another; the
+tide or waves, stirred to unusual depths by the wind, may gradually wear
+down the line of coast, or they may form shoals and coast dunes by
+depositing the sand they have rolled up from the bottom of the ocean.
+These latter modes of action are slow in producing effects sufficiently
+important to be noticed in general geography, or even to be visible in
+the representations of coast line laid down in ordinary maps; but they
+nevertheless form conspicuous features in local topography, and they are
+attended with consequences of great moment to the material and the moral
+interests of men.
+
+The forces which produce these results are all in a considerable degree
+subject to control, or rather to direction and resistance, by human
+power, and it is in guiding and combating them that man has achieved
+some of his most remarkable and honorable conquests over nature. The
+triumphs in question, or what we generally call harbor and coast
+improvements, whether we estimate their value by the money and labor
+expended upon them, or by their bearing upon the interests of commerce
+and the arts of civilization, must take a very high rank among the great
+works of man, and they are fast assuming a magnitude greatly exceeding
+their former relative importance. The extension of commerce and of the
+military marine, and especially the introduction of vessels of increased
+burden and deeper draught of water, have imposed upon engineers tasks of
+a character which a century ago would have been pronounced, and, in
+fact, would have been impracticable; but necessity has stimulated an
+ingenuity which has contrived means of executing them, and which gives
+promise of yet greater performance in time to come.
+
+Men have ceased to admire the power which heaped up the great pyramid to
+gratify the pride of a despot with a giant sepulchre; for many great
+harbors, many important lines of internal communication, in the
+civilized world, now exhibit works which surpass the vastest remains of
+ancient architectural art in mass and weight of matter, demand the
+exercise of far greater constructive skill, and involve a much heavier
+pecuniary expenditure than would now be required for the building of the
+tomb of Cheops. It is computed that the great pyramid, the solid
+contents of which when complete were about 3,000,000 cubic yards, could
+be erected for a million of pounds sterling. The breakwater at
+Cherbourg, founded in rough water sixty feet, deep, at an average
+distance of more than two miles from the shore, contains double the mass
+of the pyramid, and many a comparatively unimportant railroad has been
+constructed at twice the cost which would now build that stupendous
+monument. Indeed, although man, detached from the solid earth, is almost
+powerless to struggle against the sea, he is fast becoming invincible by
+it so long as his foot is planted on the shore, or even on the bottom of
+the rolling ocean; and though on some battle fields between the waters
+and the land, he is obliged slowly to yield his ground, yet he retreats
+still facing the foe, and will finally be able to say to the sea: "Thus
+far shalt thou come and no farther, and here shall thy proud waves be
+stayed!"
+
+The description of works of harbor and coast improvement which have only
+an economical value, not a true geographical importance, does not come
+within the plan of the present volume, and in treating this branch of my
+subject, I shall confine myself to such as are designed either to gain
+new soil by excluding the waters from grounds which they had permanently
+or occasionally covered, or to resist new encroachments of the sea upon
+the land.
+
+
+a. _Exclusion of the Sea by Diking._
+
+The draining of the Lincolnshire fens in England, which converted about
+400,000 acres of marsh, pool, and tide-washed flat into plough land and
+pasturage, is a work, or rather series of works, of great magnitude, and
+it possesses much economical, and, indeed, no trifling geographical
+importance. Its plans and methods were, at least in part, borrowed from
+the example of like improvements in Holland, and it is, in difficulty
+and extent, inferior to works executed for the same purpose on the
+opposite coast of the North Sea, by Dutch, Frisic, and Low German
+engineers. The space I can devote to such operations will be better
+employed in describing the latter, and I content myself with the simple
+statement I have already made of the quantity of worthless and even
+pestilential land which has been rendered both productive and salubrious
+in Lincolnshire, by diking out the sea, and the rivers which traverse
+the fens of that country.
+
+The almost continued prevalence of west winds upon both coasts of the
+German Ocean occasions a constant set of the currents of that sea to the
+east, and both for this reason and on account of the greater violence of
+storms from the former quarter, the English shores are much less exposed
+to invasion by the waves than those of the Netherlands and the provinces
+contiguous to them on the north. The old Netherlandish chronicles are
+filled with the most startling accounts of the damage done by the
+irruptions of the ocean, from west winds or extraordinarily high tides,
+at times long before any considerable extent of seacoast was diked.
+Several hundreds of these terrible inundations are recorded, and in very
+many of them the loss of human lives is estimated as high as one hundred
+thousand. It is impossible to doubt that there must be enormous
+exaggeration in these numbers; for, with all the reckless hardihood
+shown by men in braving the dangers and privations attached by nature to
+their birthplace, it is inconceivable that so dense a population as such
+wholesale destruction of life supposes could find the means of
+subsistence, or content itself to dwell, on a territory liable, a dozen
+times in a century, to such fearful devastation. There can be no doubt,
+however, that the low continental shores of the German Ocean very
+frequently suffered immense injury from inundation by the sea, and it is
+natural, therefore, that the various arts of resistance to the
+encroachments of the ocean, and, finally, of aggressive warfare upon its
+domain, and of permanent conquest of its territory, should have been
+earlier studied and carried to higher perfection in the latter
+countries, than in England, which had much less to lose or to gain by
+the incursions or the retreat of the waters.
+
+Indeed, although the confinement of swelling rivers by artificial
+embankments is of great antiquity, I do not know that the defence or
+acquisition of land from the sea by diking was ever practised on a large
+scale until systematically undertaken by the Netherlanders, a few
+centuries after the commencement of the Christian era. The silence of
+the Roman historians affords a strong presumption that this art was
+unknown to the inhabitants of the Netherlands at the time of the Roman
+invasion, and the elder Pliny's description of the mode of life along
+the coast which has now been long diked in, applies precisely to the
+habits of the people who live on the low islands and mainland flats
+lying outside of the chain of dikes, and wholly unprotected by
+embankments of any sort.
+
+It has been conjectured, and not without probability, that the causeways
+built by the Romans across the marshes of the Low Countries, in their
+campaigns against the Germanic tribes, gave the natives the first hint
+of the utility which might be derived from similar constructions applied
+to a different purpose.[306] If this is so, it is one of the most
+interesting among the many instances in which the arts and enginery of
+war have been so modified as to be eminently promotive of the blessings
+of peace, thereby in some measure compensating the wrongs and sufferings
+they have inflicted on humanity.[307] The Lowlanders are believed to
+have secured some coast and bay islands by ring dikes, and to have
+embanked some fresh water channels, as early as the eighth or ninth
+century; but it does not appear that sea dikes, important enough to be
+noticed in historical records, were constructed on the mainland before
+the thirteenth century. The practice of draining inland accumulation of
+water, whether fresh or salt, for the purpose of bringing under
+cultivation the ground they cover, is of later origin, and is said not
+to have been adopted until after the middle of the fifteenth
+century.[308]
+
+The total amount of surface gained to the agriculture of the Netherlands
+by diking out the sea and by draining shallow bays and lakes, is
+estimated by Staring at three hundred and fifty-five thousand _bunder_
+or hectares, equal to eight hundred and seventy-seven thousand two
+hundred and forty acres, which is one tenth of the area of the
+kingdom.[309] In very many instances, the dikes have been partially, in
+some particularly exposed localities totally destroyed by the violence
+of the sea, and the drained lands again flooded. In some cases, the soil
+thus painfully won from the ocean has been entirely lost; in others it
+has been recovered by repairing or rebuilding the dikes and pumping out
+the water. Besides this, the weight of the dikes gradually sinks them
+into the soft soil beneath, and this loss of elevation must be
+compensated by raising the surface, while the increased burden thus
+added tends to sink them still lower. "Tetens declares," says Kohl,
+"that in some places the dikes have gradually sunk to the depth of sixty
+or even a hundred feet."[310] For these reasons, the processes of dike
+building have been almost everywhere again and again repeated, and thus
+the total expenditure of money and of labor upon the works in question
+is much greater than would appear from an estimate of the actual cost of
+diking-in a given extent of coast land and draining a given area of
+water surface.[311]
+
+On the other hand, by erosion of the coast line, the drifting of sand
+dunes into the interior, and the drowning of fens and morasses by
+incursions of the sea--all caused, or at least greatly aggravated, by
+human improvidence--the Netherlands have lost a far larger area of land
+since the commencement of the Christian era than they have gained by
+diking and draining. Staring despairs of the possibility of calculating
+the loss from the first-mentioned two causes of destruction, but he
+estimates that not less than six hundred and forty thousand bunder, or
+one million five hundred and eighty-one thousand acres, of fen and marsh
+have been washed away, or rather deprived of their vegetable surface and
+covered by water, and thirty-seven thousand bunder, or ninety-one
+thousand four hundred acres of recovered land, have been lost by the
+destruction of the dikes which protected them.[312] The average value of
+land gained from the sea is estimated at about nineteen pounds sterling,
+or ninety dollars, per acre; while the lost fen and morass was not worth
+more than one twenty-fifth part of the same price. The ground buried by
+the drifting of the dunes appears to have been almost entirely of this
+latter character, and, upon the whole, there is no doubt that the soil
+added by human industry to the territory of the Netherlands, within the
+historical period, greatly exceeds in pecuniary value that which has
+fallen a prey to the waves during the same era.
+
+Upon most low and shelving coasts, like those of the Netherlands, the
+maritime currents are constantly changing, in consequence of the
+variability of the winds, and the shifting of the sandbanks, which the
+currents themselves now form and now displace. While, therefore, at one
+point the sea is advancing landward, and requiring great effort to
+prevent the undermining and washing away of the dikes, it is shoaling at
+another by its own deposits, and exposing, at low water, a gradually
+widening belt of sands and ooze. The coast lands selected for diking-in
+are always at points where the sea is depositing productive soil. The
+Eider, the Elbe, the Weser, the Ems, the Rhine, the Maas, and the
+Schelde bring down large quantities of fine earth. The prevalence of
+west winds prevents the waters from carrying this material far out from
+the coast, and it is at last deposited northward or southward from the
+mouth of the rivers which contribute it, according to the varying drift
+of the currents.
+
+The process of natural deposit which prepares the coast for diking-in is
+thus described by Staring: "All sea-deposited soil is composed of the
+same constituents. First comes a stratum of sand, with marine shells, or
+the shells of mollusks living in brackish water. If there be tides, and,
+of course, flowing and ebbing currents, mud is let fall upon the sand
+only after the latter has been raised above low-water mark; for then
+only, at the change from flood to ebb, is the water still enough to form
+a deposit of so light a material. Where mud is found at greater depths,
+as, for example, in a large proportion of the Ij, it is a proof that
+at this point there was never any considerable tidal flow or other
+current. * * * The powerful tidal currents, flowing and ebbing twice a
+day, drift sand with them. They scoop out the bottom at one point, raise
+it at another, and the sandbanks in the current are continually
+shifting. As soon as a bank raises itself above low-water mark, flags
+and reeds establish themselves upon it. The mechanical resistance of
+these plants checks the retreat of the high water and favors the deposit
+of the earth suspended in it, and the formation of land goes on with
+surprising rapidity. When it has risen to high-water level, it is soon
+covered with grasses, and becomes what is called _schor_ in Zeeland,
+_kwelder_ in Friesland. Such grounds are the foundation or starting
+point of the process of diking. When they are once elevated to the
+flood-tide level, no more mud is deposited upon them except by
+extraordinary high tides. Their further rise is, accordingly, very slow,
+and it is seldom advantageous to delay longer the operation of
+diking."[313]
+
+The formation of new banks by the sea is constantly going on at points
+favorable for the deposit of sand and earth, and hence opportunity is
+continually afforded for enclosure of new land outside of that already
+diked in, the coast is fast advancing seaward, and every new embankment
+increases the security of former enclosures. The province of Zeeland
+consists of islands washed by the sea on their western coasts, and
+separated by the many channels through which the Schelde and some other
+rivers find their way to the ocean. In the twelfth century these
+islands were much smaller and more numerous than at present. They have
+been gradually enlarged, and, in several instances, at last connected by
+the extension of their system of dikes. Walcheren is formed of ten
+islets united into one about the end of the fourteenth century. At the
+middle of the fifteenth century, Goeree and Overflakkee consisted of
+separate islands, containing altogether about ten thousand acres; by
+means of above sixty successive advances of the dikes, they have been
+brought to compose a single island, whose area is not less than sixty
+thousand acres.[314]
+
+In the Netherlands--which the first Napoleon characterized as a deposit
+of the Rhine, and as, therefore, by natural law, rightfully the property
+of him who controlled the sources of that great river--and on the
+adjacent Frisic, Low German and Danish shores and islands, sea and river
+dikes have been constructed on a grander and more imposing scale than in
+any other country. The whole economy of the art has been there most
+thoroughly studied, and the literature of the subject is very extensive.
+For my present aim, which is concerned with results rather than with
+processes, it is not worth while to refer to professional treatises, and
+I shall content myself with presenting such information as can be
+gathered from works of a more popular character.[315]
+
+The superior strata of the lowlands upon and near the coast are, as we
+have seen, principally composed of soil brought down by the great
+rivers I have mentioned, and either directly deposited by them upon the
+sands of the bottom, or carried out to sea by their currents, and then,
+after a shorter or longer exposure to the chemical and mechanical action
+of salt water and marine currents, restored again to the land by tidal
+overflow and subsidence from the waters in which it was suspended. At a
+very remote period, the coast flats were, at many points, raised so high
+by successive alluvious or tidal deposits as to be above ordinary high
+water level, but they were still liable to occasional inundation from
+river floods, and from the sea water also, when heavy or long-continued
+west winds drove it landward. The extraordinary fertility of this soil
+and its security as a retreat from hostile violence attracted to it a
+considerable population, while its want of protection against inundation
+exposed it to the devastations of which the chroniclers of the Middle
+Ages have left such highly colored pictures. The first permanent
+dwellings on the coast flats were erected upon artificial mounds, and
+many similar precarious habitations still exist on the unwalled islands
+and shores beyond the chain of dikes. River embankments, which, as is
+familiarly known, have from the earliest antiquity been employed in many
+countries where sea dikes are unknown, were probably the first works of
+this character constructed in the Low Countries, and when two
+neighboring streams of fresh water had been embanked, the next step in
+the process would naturally be to connect the river walls together by a
+transverse dike or raised causeway, which would serve to secure the
+intermediate ground both against the backwater of river floods and
+against overflow by the sea. The oldest true sea dikes described in
+historical records, however, are those enclosing islands in the
+estuaries of the great rivers, and it is not impossible that the double
+character they possess as a security against maritime floods and as a
+military rampart, led to their adoption upon those islands before
+similar constructions had been attempted upon the mainland.
+
+At some points of the coast, various contrivances, such as piers, piles,
+and, in fact, obstructions of all sorts to the ebb of the current, are
+employed to facilitate the deposit of slime, before a regular enclosure
+is commenced. Usually, however, the first step is to build low and cheap
+embankments, extending from an older dike, or from high ground, around
+the parcel of flat intended to be secured. These are called summer dikes
+(_sommer-deich_, pl. _sommer-deiche_, German; _zomerkaai_, _zomerkade_,
+pl. _zomerkaaie_, _zomerkaden_, Dutch). They are erected when a
+sufficient extent of ground to repay the cost has been elevated enough
+to be covered with coarse vegetation fit for pasturage. They serve both
+to secure the ground from overflow by the ordinary flood tides of mild
+weather, and to retain the slime deposited by very high water, which
+would otherwise be partly carried off by the retreating ebb. The
+elevation of the soil goes on slowly after this; but when it has at last
+been sufficiently enriched, and raised high enough to justify the
+necessary outlay, permanent dikes are constructed by which the water is
+excluded at all seasons. These embankments are constructed of sand from
+the coast dunes or from sandbanks, and of earth from the mainland or
+from flats outside the dikes, bound and strengthened by fascines, and
+provided with sluices, which are generally founded on piles and of very
+expensive construction, for drainage at low water. The outward slope of
+the sea dikes is gentle, experience having shown that this form is least
+exposed to injury both from the waves and from floating ice, and the
+most modern dikes are even more moderate in the inclination of the
+seaward scarp than the older ones.[316] The crown of the dike, however,
+for the last three or four feet of its height, is much steeper, being
+intended rather as a protection against the spray than against the
+waves, and the inner slope is always comparatively abrupt.
+
+The height and thickness of dikes varies according to the elevation of
+the ground they enclose, the rise of the tides, the direction of the
+prevailing winds, and other special causes of exposure, but it may be
+said that they are, in general, raised from fifteen to twenty feet above
+ordinary high-water mark. The water slopes of river dikes are protected
+by plantations of willows or strong semi-aquatic shrubs or grasses, but
+as these will not grow upon banks exposed to salt water, sea dikes must
+be faced with stone, fascines, or some other _revetement_.[317] Upon the
+coast of Schleswig and Holstein, where the people have less capital at
+their command, they defend their embankments against ice and the waves
+by a coating of twisted straw or reeds, which must be renewed as often
+as once, sometimes twice a year. The inhabitants of these coasts call
+the chain of dikes "the golden border," a name it well deserves, whether
+we suppose it to refer to its enormous cost, or, as is more probable, to
+its immense value as a protection to their fields and their firesides.
+
+When outlying flats are enclosed by building new embankments, the old
+interior dikes are suffered to remain, both as an additional security
+against the waves, and because the removal of them would be expensive.
+They serve, also, as roads or causeways, a purpose for which the
+embankments nearest the sea are seldom employed, because the whole
+structure might be endangered from the breaking of the turf by wheels
+and the hoofs of horses. Where successive rows of dikes have been thus
+constructed, it is observed that the ground defended by the more ancient
+embankments is lower than that embraced within the newer enclosures, and
+this depression of level has been ascribed to a general subsidence of
+the coast from geological causes; but the better opinion seems to be
+that it is, in most cases, due merely to the consolidation and settling
+of the earth from being more effectually dried, from the weight of the
+dikes, from the tread of men and cattle, and from the movement of the
+heavy wagons which carry off the crops.[318] Notwithstanding this slow
+sinking, most of the land enclosed by dikes is still above low-water
+mark, and can, therefore, be wholly or partially freed from rain water,
+and from that received by infiltration from higher ground, by sluices
+opened at the ebb of the tide. For this purpose, the land is carefully
+ditched, and advantage is taken of every favorable occasion for
+discharging the water through the sluices. But the ground cannot be
+effectually drained by this means, unless it is elevated four or five
+feet, at least, above the level of the ebb tide, because the ditches
+would not otherwise have a sufficient descent to carry the water off in
+the short interval between ebb and flow, and because the moisture of the
+saturated subsoil is always rising by capillary attraction. Whenever,
+therefore, the soil has sunk below the level I have mentioned, and in
+cases where its surface has never been raised above it, pumps, worked by
+wind or some other mechanical power, must be very frequently employed to
+keep the land dry enough for pasturage and cultivation.[319]
+
+
+b. _Draining of Lakes and Marshes._
+
+The substitution of steam engines for the feeble and uncertain action of
+windmills, in driving pumps, has much facilitated the removal of water
+from the polders and the draining of lakes, marshes, and shallow bays,
+and thus given such an impulse to these enterprises, that not less than
+one hundred and ten thousand acres were reclaimed from the waters, and
+added to the agricultural domain of the Netherlands, between 1815 and
+1858. The most important of these undertakings was the draining of the
+Lake of Haarlem, and for this purpose some of the most powerful
+hydraulic engines ever constructed were designed and executed.[320] The
+origin of this lake is unknown. It is supposed by some geographers to be
+a part of an ancient bed of the Rhine, the channel of which, as there is
+good reason to believe, has undergone great changes since the Roman
+invasion of the Netherlands; by others it is thought to have once formed
+an inland marine channel, separated from the sea by a chain of low
+islands, which the sand washed up by the tides has since connected with
+the mainland and converted into a continuous line of coast. The best
+authorities, however, find geological evidence that the surface occupied
+by the lake was originally a marshy tract containing within its limits
+little solid ground, but many ponds and inlets, and much floating as
+well as fixed fen.
+
+In consequence of the cutting of turf for fuel, and the destruction of
+the few trees and shrubs which held the loose soil together with their
+roots, the ponds are supposed to have gradually extended themselves,
+until the action of the wind upon their enlarged surface gave their
+waves sufficient force to overcome the resistance of the feeble barriers
+which separated them, and to unite them all into a single lake. Popular
+tradition, it is true, ascribes the formation of the Lake of Haarlem to
+a single irruption of the sea, at a remote period, and connects it with
+one or another of the destructive inundations of which the Netherland
+chronicles describe so many; but on a map of the year 1531, a chain of
+four smaller waters occupies nearly the ground afterward covered by the
+Lake of Haarlem, and they have more probably been united by gradual
+encroachments resulting from the improvident practices above referred
+to, though no doubt the consummation may have been hastened by floods,
+and by the neglect to maintain dikes, or the intentional destruction of
+them, in the long wars of the sixteenth century.
+
+The Lake of Haarlem was a body of water not far from fifteen miles in
+length, by seven in greatest width, lying between the cities of
+Amsterdam and Leyden, running parallel with the coast of Holland at the
+distance of about five miles from the sea, and covering an area of about
+45,000 acres. By means of the Ij, it communicated with the Zuiderzee,
+the Mediterranean of the Netherlands, and its surface was little above
+the mean elevation of that of the sea. Whenever, therefore, the waters
+of the Zuiderzee were acted upon by strong northwest winds, those of the
+Lake of Haarlem were raised proportionally and driven southward, while
+winds from the south tended to create a flow in the opposite direction.
+The shores of the lake were everywhere low, and though in the course of
+the eighty years between 1767 and 1848 more than L350,000 or $1,700,000
+had been expended in checking its encroachments, it often burst its
+barriers, and produced destructive inundations. On the 29th of November,
+1836, a south wind brought its waters to the very gates of Amsterdam,
+and on the 26th of December of the same year, in a northwest gale, they
+overflowed twenty thousand acres of land at the southern extremity of
+the lake, and flooded a part of the city of Leyden. The depth of water
+did not, in general, exceed fourteen feet, but the bottom was a
+semi-fluid ooze or slime, which partook of the agitation of the waves,
+and added considerably to their mechanical force. Serious fears were
+entertained that the lake would form a junction with the inland waters
+of the Legmeer and Mijdrecht, swallow up a vast extent of valuable soil,
+and finally endanger the security of a large proportion of the land
+which the industry of Holland had gained in the course of centuries from
+the ocean.
+
+For this reason, and for the sake of the large addition the bottom of
+the lake would make to the cultivable soil of the state, it was resolved
+to drain it, and the preliminary steps for that purpose were commenced
+in the year 1840. The first operation was to surround the entire lake
+with a ring canal and dike, in order to cut off the communication with
+the Ij, and to exclude the water of the streams and morasses which
+discharged themselves into it from the land side. The dike was composed
+of different materials, according to the means of supply at different
+points, such as sand from the coast dunes, earth and turf excavated from
+the line of the ring canal, and floating turf,[321] fascines being
+everywhere used to bind and compact the mass together. This operation
+was completed in 1848, and three steam pumps were then employed for five
+years in discharging the water. The whole enterprise was conducted at
+the expense of the state, and in 1853 the recovered lands were offered
+for sale for its benefit. Up to 1858, forty-two thousand acres had been
+sold at not far from sixteen pounds sterling or seventy-seven dollars an
+acre, amounting altogether to L661,000 sterling or $3,200,000. The
+unsold lands were valued at more than L6,000 or nearly $30,000, and as
+the total cost was L764,500 or about $3,700,000, the direct loss to the
+state, exclusive of interest on the capital expended, may be stated at
+L100,000 or something less than $500,000.
+
+In a country like the United States, of almost boundless extent of
+sparsely inhabited territory, such an expenditure for such an object
+would be poor economy. But Holland has a narrow domain, great pecuniary
+resources, an excessively crowded population, and a consequent need of
+enlarged room and opportunity for the exercise of industry. Under such
+circumstances, and especially with an exposure to dangers so formidable,
+there is no question of the wisdom of the measure. It has already
+provided homes and occupation for more than five thousand citizens, and
+furnished a profitable investment for a capital of not less than
+L400,000 sterling or $2,000,000, which has been expended in improvements
+over and above the purchase money of the soil; and the greater part of
+this sum, as well as of the cost of drainage, has been paid as a
+compensation for labor. The excess of governmental expenditure over the
+receipts, if employed in constructing ships of war or fortifications,
+would have added little to the military strength of the kingdom; but the
+increase of territory, the multiplication of homes and firesides which
+the people have an interest in defending, and the augmentation of
+agricultural resources, constitute a stronger bulwark against foreign
+invasion than a ship of the line or a fortress armed with a hundred
+cannon.
+
+The bearing of the works I have noticed, and of others similar in
+character, upon the social and moral, as well as the purely economical
+interests of the people of the Netherlands, has induced me to describe
+them more in detail than the general purpose of this volume may be
+thought to justify; but if we consider them simply from a geographical
+point of view, we shall find that they are possessed of no small
+importance as modifications of the natural condition of terrestrial
+surface. There is good reason to believe that before the establishment
+of a partially civilized race upon the territory now occupied by Dutch,
+Frisic, and Low German communities, the grounds not exposed to
+inundation were overgrown with dense woods, that the lowlands between
+these forests and the sea coasts were marshes, covered and partially
+solidified by a thick matting of peat plants and shrubs interspersed
+with trees, and that even the sand dunes of the shore were protected by
+a vegetable growth which, in a great measure, prevented the drifting and
+translocation of them.
+
+The present causes of river and coast erosion existed, indeed, at the
+period in question; but some of them must have acted with less
+intensity, there were strong natural safeguards against the influence of
+marine and fresh-water currents, and the conflicting tendencies had
+arrived at a condition of approximate equilibrium, which permitted but
+slow and gradual changes in the face of nature. The destruction of the
+forests around the sources and along the valleys of the rivers by man
+gave them a more torrential character. The felling of the trees, and the
+extirpation of the shrubbery upon the fens by domestic cattle, deprived
+the surface of cohesion and consistence, and the cutting of peat for
+fuel opened cavities in it, which, filling at once with water, rapidly
+extended themselves by abrasion of their borders, and finally enlarged
+to pools, lakes, and gulfs, like the Lake of Haarlem and the northern
+part of the Zuiderzee. The cutting of the wood and the depasturing of
+the grasses upon the sand dunes converted them from solid bulwarks
+against the ocean to loose accumulations of dust, which every sea breeze
+drove farther landward, burying, perhaps, fertile soil and choking up
+watercourses on one side, and exposing the coast to erosion by the sea
+upon the other.
+
+
+c. _Geographical Influence of such Operations._
+
+The changes which human action has produced within twenty centuries in
+the Netherlands and the neighboring provinces, are certainly of no small
+geographical importance, considered simply as a direct question of loss
+and gain of territory. They have also undoubtedly been attended with
+some climatic consequences, they have exercised a great influence on the
+spontaneous animal and vegetable life of this region, and they cannot
+have failed to produce effects upon tidal and other oceanic currents,
+the range of which may be very extensive. The force of the tidal wave,
+the height to which it rises, the direction of its currents, and, in
+fact, all the phenomena which characterize it, as well as all the
+effects it produces, depend as much upon the configuration of the coast
+it washes, and the depth of water, and form of bottom near the shore, as
+upon the attraction which occasions it. Every one of the terrestrial
+conditions which affect the character of tidal and other marine currents
+has been very sensibly modified by the operations I have described, and
+on this coast, at least, man has acted almost as powerfully on the
+physical geography of the sea as on that of the land.
+
+
+_Lowering of Lakes._
+
+The hydraulic works of the Netherlands and of the neighboring states are
+of such magnitude, that they quite throw into the shade all other known
+artificial arrangements for defending the land against the encroachments
+of the rivers and the sea, and for reclaiming to the domain of
+agriculture and civilization soil long covered by the waters. But
+although the recovery and protection of lands flooded by the sea seems
+to be an art wholly of Netherlandish origin, we have abundant evidence,
+that in ancient as well as in comparatively modern times, great
+enterprises more or less analogous in character have been successfully
+undertaken, both in inland Europe and in the less familiar countries of
+the East.
+
+One of the best known of these is the tunnel which serves to discharge
+the surplus waters of the Lake of Albano, about fourteen miles from
+Rome. This lake, about six miles in circuit, occupies one of the craters
+of an extinct volcanic range, and the surface of its waters is about
+nine hundred feet above the sea. It is fed by rivulets and subterranean
+springs originating in the Alban Mount, or Monte Cavo, the most elevated
+peak of the volcanic group just mentioned, which rises to the height of
+about three thousand feet. At present the lake has no discoverable
+natural outlet, but it is not known that the water ever stood at such a
+height as to flow regularly over the lip of the crater. It seems that at
+the earliest period of which we have any authentic memorials, its level
+was usually kept by evaporation, or by discharge through subterranean
+channels, considerably below the rim of the basin which encompassed it,
+but in the year 397 B. C., the water, either from the obstruction of
+such channels, or in consequence of increased supplies from unknown
+sources, rose to such a height as to flow over the edge of the crater,
+and threaten inundation to the country below by bursting through its
+walls. To obviate this danger, a tunnel for carrying off the water was
+pierced at a level much below the height to which it had risen. This
+gallery, cut entirely with the chisel through the rock for a distance
+of six thousand feet, or nearly a mile and one seventh, is still in so
+good condition as to serve its original purpose. The fact that this work
+was contemporaneous with the siege of Veii, has given to ancient
+annalists occasion to connect the two events, but modern critics are
+inclined to reject Livy's account of the matter, as one of the many
+improbable fables which disfigure the pages of that historian. It is,
+however, repeated by Cicero and by Dionysins of Halicarnassus, and it is
+by no means impossible that, in an age when priests and soothsayers
+monopolized both the arts of natural magic and the little which yet
+existed of physical science, the Government of Rome, by their aid,
+availed itself at once of the superstition and of the military ardor of
+its citizens to obtain their sanction to an enterprise which sounder
+arguments might not have induced them to approve.
+
+Still more remarkable is the tunnel cut by the Emperor Claudius to drain
+the Lake Fucinus, now Lago di Celano, in the Neapolitan territory, about
+fifty miles eastward of Rome. This lake, as far as its history is known,
+has varied very considerably in its dimensions at different periods,
+according to the character of the seasons. It has no visible outlet, but
+was originally either drained by natural subterranean conduits, or kept
+within certain extreme limits by evaporation. In years of uncommon
+moisture, it spread over the adjacent soil and destroyed the crops; in
+dry seasons, it retreated, and produced epidemic disease by poisonous
+exhalations from the decay of vegetable and animal matter upon its
+exposed bed. Julius Caesar had proposed the construction of a tunnel to
+drain the lake, but the enterprise was not actually undertaken until the
+reign of Claudius, when--after a temporary failure, from errors in
+levelling by the engineers, as was pretended at the time, or, as now
+appears certain, in consequence of frauds by the contractors in the
+execution of the work--it was at least partially completed. From this
+imperfect construction, it soon got out of repair, but was restored by
+Hadrian, and seems to have answered its design for some centuries. In
+the barbarism which followed the downfall of the empire, it again fell
+into decay, and though numerous attempts were made to repair it during
+the Middle Ages, no tolerable success seems to have attended any of
+these efforts, until the present generation.
+
+Works have now been some years in progress for restoring, or rather
+enlarging and rebuilding this ancient tunnel, upon a scale of grandeur
+which does infinite honor to the liberality and public spirit of the
+projectors, and with an ingenuity of design and a constructive skill
+which reflect the highest credit upon the professional ability of the
+engineers who have planned the works and directed their execution. The
+length of this tunnel is 18,634 feet, or rather more than three miles
+and a half. Of course, it is one of the longest subterranean galleries
+yet executed in Europe, and it offers many curious particulars in its
+original design which cannot here be described. The difference between
+the highest and the lowest known levels of the surface of the lake
+amounts to at least forty feet, and the difference of area covered at
+these respective stages is not much less than eight thousand acres. The
+tunnel will reduce the water to a much lower point, and it is computed
+that, including the lands occasionally overflowed, not less than forty
+thousand acres of as fertile soil as any in Italy will be recovered from
+the lake and permanently secured from inundation by its waters.
+
+Many similar enterprises have been conceived and executed in modern
+times, both for the purpose of reclaiming land covered by water and for
+sanitary reasons.[322] They are sometimes attended with wholly
+unexpected evils, as, for example, in the case of Barton Pond, in
+Vermont, and in that of the Lake Storsjoe, in Sweden, already mentioned
+on a former page. Another still less obvious consequence of the
+withdrawal of the waters has occasionally been observed in these
+operations. The hydrostatic force with which the water, in virtue of its
+specific gravity, presses against the banks that confine it, has a
+tendency to sustain them whenever their composition and texture are not
+such as to expose them to softening and dissolution by the infiltration
+of the water. If then, the slope of the banks is considerable, or if the
+earth of which they are composed rests on a smooth and slippery stratum
+inclining toward the bed of the lake, they are liable to fall or slide
+forward when the mechanical support of the water is removed, and this
+sometimes happens on a considerable scale. A few years ago, the surface
+of the Lake of Lungern, in the Canton of Unterwalden, in Switzerland,
+was lowered by driving a tunnel about a quarter of a mile long through
+the narrow ridge, called the Kaiserstuhl, which forms a barrier at the
+north end of the basin. When the water was drawn off, the banks, which
+are steep, cracked and burst, several acres of ground slid down as low
+as the water receded, and even the whole village of Lungern was thought
+to be in no small danger.
+
+Other inconveniences of a very serious character have often resulted
+from the natural wearing down, or, much more frequently, the imprudent
+destruction, of the barriers which confine mountain lakes. In their
+natural condition, such basins serve both to receive and retain the
+rocks and other detritus brought down by the torrents which empty into
+them, and to check the impetus of the rushing waters by bringing them to
+a temporary pause; but if the outlets are lowered so as to drain the
+reservoirs, the torrents continue their rapid flow through the ancient
+bed of the basins, and carry down with them the sand and gravel with
+which they are charged, instead of depositing their burden as before in
+the still waters of the lakes.
+
+
+_Mountain Lakes._
+
+It is a common opinion in America that the river meadows, bottoms, or
+_intervales_, as they are popularly called, are generally the beds of
+ancient lakes which have burst their barriers and left running currents
+in their place. It was shown by Dr. Dwight, many years ago, that this is
+very far from being universally true; but there is no doubt that
+mountain lakes were of much more frequent occurrence in primitive than
+in modern geography, and there are many chains of such still existing in
+regions where man has yet little disturbed the original features of the
+earth. In the long valleys of the Adirondack range in Northern New York,
+and in the mountainous parts of Maine, eight, ten, and even more lakes
+and lakelets are sometimes found in succession, each emptying into the
+next lower pool, and so all at last into some considerable river. When
+the mountain slopes which supply these basins shall be stripped of their
+woods, the augmented swelling of the lakes will break down their
+barriers, their waters will run off, and the valleys will present
+successions of flats with rivers running through them, instead of chains
+of lakes connected by natural canals.
+
+A similar state of things seems to have existed in the ancient geography
+of France. "Nature," says Lavergne, "has not excavated on the flanks of
+our Alps reservoirs as magnificent as those of Lombardy; she had,
+however, constructed smaller, but more numerous lakes, which the
+negligence of man has permitted to disappear. Auguste de Gasparin,
+brother of the illustrious agriculturist, demonstrated more than thirty
+years ago, in an original paper, that many natural dikes formerly
+existed in the mountain valleys, which have been swept away by the
+waters. He proposed to rebuild and to multiply them. This interesting
+suggestion has reappeared several times since, but has met with strong
+opposition from skilful engineers. It would, nevertheless, be well to
+try the experiment of creating artificial lakes which should fill
+themselves with the water of melting snows and deluging rains, to be
+drawn out in times of drought. If this plan has able opposers, it has
+also warm advocates. Experience alone can decide the question."[323]
+
+
+_Climatic Effects of Draining Lakes and Marshes._
+
+The draining of lakes, marshes, and other superficial accumulations of
+moisture, reduces the water surface of a country, and, of course, the
+evaporation from it. Lakes, too, in elevated positions, lose a part of
+their water by infiltration, and thereby supply other lakes, springs,
+and rivulets at lower levels. Hence, it is evident that the draining of
+such waters, if carried on upon a large scale, must affect both the
+humidity and the temperature of the atmosphere, and the permanent supply
+of water for extensive districts.[324]
+
+
+_Geographical and Climatic Effects of Aqueducts, Reservoirs, and
+Canals._
+
+Many processes of internal improvement, such as aqueducts for the supply
+of great cities, railroad cuts and embankments, and the like, divert
+water from its natural channels, and affect its distribution and
+ultimate discharge. The collecting of the waters of a considerable
+district into reservoirs, to be thence carried off by means of
+aqueducts, as, for example, in the forest of Belgrade, near
+Constantinople, deprives the grounds originally watered by the springs
+and rivulets of the necessary moisture, and reduces them to barrenness.
+Similar effects must have followed from the construction of the numerous
+aqueducts which supplied ancient Rome with such a profuse abundance of
+water. On the other hand, the filtration of water through the banks or
+walls of an aqueduct carried upon a high level across low ground, often
+injures the adjacent soil, and is prejudicial to the health of the
+neighboring population; and it has been observed in Switzerland, that
+fevers have been produced by the stagnation of the water in excavations
+from which earth had been taken to form embankments for railways.
+
+If we consider only the influence of physical improvements on civilized
+life, we shall perhaps ascribe to navigable canals a higher importance,
+or at least a more diversified influence, than to any other works of man
+designed to control the waters of the earth, and to affect their
+distribution, They bind distant regions together by social ties, through
+the agency of the commerce they promote; they facilitate the
+transportation of military stores and engines, and of other heavy
+material connected with the discharge of the functions of government;
+they encourage industry by giving marketable value to raw material and
+to objects of artificial elaboration which would otherwise be worthless
+on account of the cost of conveyance; they supply from their surplus
+waters means of irrigation and of mechanical power; and, in many other
+ways, they contribute much to advance the prosperity and civilization of
+nations. Nor are they wholly without geographical importance. They
+sometimes drain lands by conveying off water which would otherwise
+stagnate on the surface, and, on the other hand, like aqueducts, they
+render the neighboring soil cold and moist by the percolation of water
+through their embankments;[325] they dam up, check, and divert the
+course of natural currents, and deliver them at points opposite to, or
+distant from, their original outlets; they often require extensive
+reservoirs to feed them, thus retaining through the year accumulations
+of water--which would otherwise run off, or evaporate in the dry
+season--and thereby enlarging the evaporable surface of the country; and
+we have already seen that they interchange the flora and the fauna of
+provinces widely separated by nature. All these modes of action
+certainly influence climate and the character of terrestrial surface,
+though our means of observation are not yet perfected enough to enable
+us to appreciate and measure their effects.
+
+
+_Climatic and Geographical Effects of Surface and Underground Draining._
+
+I have commenced this chapter with a description of the dikes and other
+hydraulic works of the Netherland engineers, because the geographical
+results of such operations are more obvious and more easily measured,
+though certainly not more important, than those of the older and more
+widely diffused modes of resisting or directing the flow of waters,
+which have been practised from remote antiquity in the interior of all
+civilized countries. Draining and irrigation are habitually regarded as
+purely agricultural processes, having little or no relation to technical
+geography; but we shall find that they exert a powerful influence on
+soil, climate, and animal and vegetable life, and may, therefore, justly
+claim to be regarded as geographical elements.
+
+
+_Surface and Under-draining and their Effects._
+
+Superficial draining is a necessity in all lands newly reclaimed from
+the forest. The face of the ground in the woods is never so regularly
+inclined as to permit water to flow freely over it. There are, even on
+the hillsides, many small ridges and depressions, partly belonging to
+the original distribution of the soil, and partly occasioned by
+irregularities in the growth and deposit of vegetable matter. These, in
+the husbandry of nature, serve as dams and reservoirs to collect a
+larger supply of moisture than the spongy earth can at once imbibe.
+Besides this, the vegetable mould is, even under the most favorable
+circumstances, slow in parting with the humidity it has accumulated
+under the protection of the woods, and the infiltration from neighboring
+forests contributes to keep the soil of small clearings too wet for the
+advantageous cultivation of artificial crops. For these reasons, surface
+draining must have commenced with agriculture itself, and there is
+probably no cultivated district, one may almost say no single field,
+which is not provided with artificial arrangements for facilitating the
+escape of superficial water, and thus carrying off moisture which, in
+the natural condition of the earth, would have been imbibed by the soil.
+
+The beneficial effects of surface drainage, the necessity of extending
+the fields as population increased, and the inconveniences resulting
+from the presence of marshes in otherwise improved regions, must have
+suggested at a very early period of human industry the expediency of
+converting bogs and swamps into dry land by drawing off their waters;
+and it would not be long after the introduction of this practice before
+further acquisition of agricultural territory would be made by lowering
+the outlet of small ponds and lakes, and adding the ground they covered
+to the domain of the husbandman.
+
+All these processes belong to the incipient civilization of the
+ante-historical periods, but the construction of subterranean channels
+for the removal of infiltrated water marks ages and countries
+distinguished by a great advance in agricultural theory and practice, a
+great accumulation of pecuniary capital, and a density of population
+which creates a ready demand and a high price for all products of rural
+industry. Under-draining, too, would be most advantageous in damp and
+cool climates, where evaporation is slow, and upon soils where the
+natural inclination of surface does not promote a very rapid flow of the
+surface waters. All the conditions required to make this mode of rural
+improvement, if not absolutely necessary, at least apparently
+profitable, exist in Great Britain, and it is, therefore, very natural
+that the wealthy and intelligent farmers of England should have carried
+this practice farther, and reaped a more abundant pecuniary return from
+it, than those of any other country.
+
+Besides superficial and subsoil drains, there is another method of
+disposing of superfluous surface water, which, however, can rarely be
+practised, because the necessary conditions for its employment are not
+of frequent occurrence. Whenever a tenacious water-holding stratum rests
+on a loose, gravelly bed, so situated as to admit of a free discharge of
+water from or through it by means of the outcropping of the bed at a
+lower level, or of deep-lying conduits leading to distant points of
+discharge, superficial waters may be carried off by opening a passage
+for them through the impervious into the permeable stratum. Thus,
+according to Bischof, as early as the time of King Rene, in the first
+half of the fifteenth century, the plain of Paluns, near Marseilles, was
+laid dry by boring, and Wittwer informs us that drainage is effected at
+Munich by conducting the superfluous water into large excavations, from
+which it filters through into a lower stratum of pebble and gravel lying
+a little above the level of the river Isar.[326] So at Washington, in
+the western part of the city, which lies high above the rivers Potomac
+and Rock Creek, many houses are provided with dry wells for draining
+their cellars and foundations. These extend through hard tenacious earth
+to the depth of thirty or forty feet, when they strike a stratum of
+gravel, through which the water readily passes off.
+
+This practice has been extensively employed at Paris, not merely for
+carrying off ordinary surface water, but for the discharge of offensive
+and deleterious fluids from chemical and manufacturing establishments. A
+well of this sort received, in the winter of 1832-'33, twenty thousand
+gallons per day of the foul water from a starch factory, and the same
+process was largely used in other factories. The apprehension of injury
+to common and artesian wells and springs led to an investigation on this
+subject, in behalf of the municipal authorities, by Girard and Parent
+Duchatelet, in the latter year. The report of these gentlemen, published
+in the _Annales des Ponts et Chaussees_ for 1833, second half year, is
+full of curious and instructive facts respecting the position and
+distribution of the subterranean waters under and near Paris; but it
+must suffice to say that the report came to the conclusion that, in
+consequence of the absolute immobility of these waters, and the
+relatively small quantity of noxious fluid to be conveyed to them, there
+was no danger of the diffusion of this latter, if discharged into them.
+This result will not surprise those who know that, in another work,
+Duchatelet maintains analogous opinions as to the effect of the
+discharge of the city sewers into the Seine upon the waters of that
+river. The quantity of matter delivered by them he holds to be so nearly
+infinitesimal, as compared with the volume of water of the Seine, that
+it cannot possibly affect it to a sensible degree. I would, however,
+advise determined water drinkers living at Paris to adopt his
+conclusions, without studying his facts and his arguments; for it is
+quite possible that he may convert his readers to a faith opposite to
+his own, and that they will finally agree with the poet who held water
+an "ignoble beverage."
+
+
+_Climatic and Geographical Effects of Surface Draining._
+
+When we remove water from the surface, we diminish the evaporation from
+it, and, of course, the refrigeration which accompanies all evaporation
+is diminished in proportion. Hence superficial draining ought to be
+attended with an elevation of atmospheric temperature, and, in cold
+countries, it might be expected to lessen the frequency of frosts.
+Accordingly, it is a fact of experience that, other things being equal,
+dry soils, and the air in contact with them, are perceptibly warmer
+during the season of vegetation, when evaporation is most rapid, than
+moist lands and the atmospheric stratum resting upon them. Instrumental
+observation on this special point has not yet been undertaken on a very
+large scale, but still we have thermometric data sufficient to warrant
+the general conclusion, and the influence of drainage in diminishing the
+frequency of frost appears to be even better established than a direct
+increase of atmospheric temperature. The steep and dry uplands of the
+Green Mountain range in New England often escape frosts when the Indian
+corn harvest on moister grounds, five hundred or even a thousand feet
+lower, is destroyed or greatly injured by them. The neighborhood of a
+marsh is sure to be exposed to late spring and early autumnal frosts,
+but they cease to be feared after it is drained, and this is
+particularly observable in very cold climates, as, for example, in
+Lapland.[327]
+
+In England, under-drains are not generally laid below the reach of daily
+variations of temperature, or below a point from which moisture might be
+brought to the surface by capillary attraction and evaporated by the
+heat of the sun. They, therefore, like surface drains, withdraw from
+local solar action much moisture which would otherwise be vaporized by
+it, and, at the same time, by drying the soil above them, they increase
+its effective hygroscopicity, and it consequently absorbs from the
+atmosphere a greater quantity of water than it did when, for want of
+under-drainage, the subsoil was always humid, if not saturated.
+Under-drains, then, contribute to the dryness as well as to the warmth
+of the atmosphere, and, as dry ground is more readily heated by the rays
+of the sun than wet, they tend also to raise the mean, and especially
+the summer temperature of the soil.
+
+So far as respects the immediate improvement of soil and climate, and
+the increased abundance of the harvests, the English system of surface
+and subsoil drainage has fully justified the eulogiums of its advocates;
+but its extensive adoption appears to have been attended with some
+altogether unforeseen and undesirable consequences, very analogous to
+those which I have described as resulting from the clearing of the
+forests. The under-drains carry off very rapidly the water imbibed by
+the soil from precipitation, and through infiltration from neighboring
+springs or other sources of supply. Consequently, in wet seasons, or
+after heavy rains, a river bordered by artificially drained lands
+receives in a few hours, from superficial and from subterranean
+conduits, an accession of water which, in the natural state of the
+earth, would have reached it only by small instalments after percolating
+through hidden paths for weeks or even months, and would have furnished
+perennial and comparatively regular contributions, instead of swelling
+deluges, to its channel. Thus, when human impatience rashly substitutes
+swiftly acting artificial contrivances for the slow methods by which
+nature drains the surface and superficial strata of a river basin, the
+original equilibrium is disturbed, the waters of the heavens are no
+longer stored up in the earth to be gradually given out again, but are
+hurried out of man's domain with wasteful haste; and while the
+inundations of the river are sudden and disastrous, its current, when
+the drains have run dry, is reduced to a rivulet, it ceases to supply
+the power to drive the machinery for which it was once amply sufficient,
+and scarcely even waters the herds that pasture upon its margin.[328]
+
+
+_Irrigation and its Climatic and Geographical Effects._
+
+We know little of the history of the extinct civilizations which
+preceded the culture of the classic ages, and no nation has, in modern
+times, spontaneously emerged from barbarism, and created for itself the
+arts of social life.[329] The improvements of the savage races whose
+history we can distinctly trace are borrowed and imitative, and our
+theories as to the origin and natural development of industrial art are
+conjectural. Of course, the relative antiquity of particular branches of
+human industry depends much upon the natural character of soil, climate,
+and spontaneous vegetable and animal life in different countries; and
+while the geographical influence of man would, under given
+circumstances, be exerted in one direction, it would, under different
+conditions, act in an opposite or a diverging line. I have given some
+reasons for thinking that in the climates to which our attention has
+been chiefly directed, man's first interference with the natural
+arrangement and disposal of the waters was in the way of drainage of
+surface. But if we are to judge from existing remains alone, we should
+probably conclude that irrigation is older than drainage; for, in the
+regions regarded by general tradition as the cradle of the human race,
+we find traces of canals evidently constructed for the former purpose at
+a period long preceding the ages of which we have any written memorials.
+There are, in ancient Armenia, extensive districts which were already
+abandoned to desolation at the earliest historical epoch, but which, in
+a yet remoter antiquity, had been irrigated by a complicated and highly
+artificial system of canals, the lines of which can still be followed;
+and there are, in all the highlands where the sources of the Euphrates
+rise, in Persia, in Egypt, in India, and in China, works of this sort
+which must have been in existence before man had begun to record his own
+annals.
+
+In warm countries, such as most of those just mentioned, the effects I
+have described as usually resulting from the clearing of the forests
+would very soon follow. In such climates, the rains are inclined to be
+periodical; they are also violent, and for these reasons the soil would
+be parched in summer and liable to wash in winter. In these countries,
+therefore, the necessity for irrigation must soon have been felt, and
+its introduction into mountainous regions like Armenia must have been
+immediately followed by a system of terracing, or at least scarping the
+hillsides. Pasture and meadow, indeed, may be irrigated even when the
+surface is both steep and irregular, as may be observed abundantly on
+the Swiss as well as on the Piedmontese slope of the Alps; but in dry
+climates, plough land and gardens on hilly grounds require terracing,
+both for supporting the soil and for administering water by irrigation,
+and it should be remembered that terracing, of itself, even without
+special arrangements for controlling the distribution of water, prevents
+or at least checks the flow of rain water, and gives it time to sink
+into the ground instead of running off over the surface.
+
+There are few things in Continental husbandry which surprise English or
+American observers so much as the extent to which irrigation is employed
+in agriculture, and that, too, on soils, and with a temperature, where
+their own experience would have led them to suppose it would be
+injurious to vegetation rather than beneficial to it. The summers in
+Northern Italy, though longer, are very often not warmer than in New
+England; and in ordinary years, the summer rains are as frequent and as
+abundant in the former country as in the latter. Yet in Piedmont and
+Lombardy, irrigation is bestowed upon almost every crop, while in New
+England it is never employed at all in farming husbandry, or indeed for
+any purpose except in kitchen gardens, and possibly, in rare cases, in
+some other small branch of agricultural industry.[330]
+
+The summers in Egypt, in Syria, and in Asia Minor and even Rumelia, are
+almost rainless. In such climates, the necessity of irrigation is
+obvious, and the loss of the ancient means of furnishing it readily
+explains the diminished fertility of most of the countries in
+question.[331] The surface of Palestine, for example, is composed, in a
+great measure, of rounded limestone hills, once, no doubt, covered with
+forests. These were partially removed before the Jewish conquest.[332]
+When the soil began to suffer from drought, reservoirs to retain the
+waters of winter were hewn in the rock near the tops of the hills, and
+the declivities were terraced. So long as the cisterns were in good
+order, and the terraces kept up, the fertility of Palestine was
+unsurpassed, but when misgovernment and foreign and intestine war
+occasioned the neglect or destruction of these works--traces of which
+still meet the traveller's eye at every step,--when the reservoirs were
+broken and the terrace walls had fallen down, there was no longer water
+for irrigation in summer, the rains of winter soon washed away most of
+the thin layer of earth upon the rocks, and Palestine was reduced almost
+to the condition of a desert.
+
+The course of events has been the same in Idumaea. The observing
+traveller discovers everywhere about Petra, particularly if he enters
+the city by the route of Wadi Ksheibeh, very extensive traces of ancient
+cultivation, and upon the neighboring ridges are the ruins of numerous
+cisterns evidently constructed to furnish a supply of water for
+irrigation.[333] In primitive ages, the precipitation of winter in
+these hilly countries was, in great part, retained for a time in the
+superficial soil, first by the vegetable mould of the forests, and then
+by the artificial arrangements I have described. The water imbibed by
+the earth was partly taken up by direct evaporation, partly absorbed by
+vegetation, and partly carried down by infiltration to subjacent strata
+which gave it out in springs at lower levels, and thus a fertility of
+soil and a condition of the atmosphere were maintained sufficient to
+admit of the dense population that once inhabited those now arid wastes.
+At present, the rain water runs immediately off from the surface and is
+carried down to the sea, or is drunk up by the sands of the wadis, and
+the hillsides which once teemed with plenty are bare of vegetation, and
+seared by the scorching winds of the desert.
+
+In Southern Europe, in the Turkish Empire, and in many other countries,
+a very large proportion of the surface is, if not absolutely flooded, at
+least thoroughly moistened by irrigation, a great number of times in the
+course of every season, and this, especially, at periods when it would
+otherwise be quite dry, and when, too, the power of the sun and the
+capacity of the air for absorbing moisture are greatest. Hence it is
+obvious that the amount of evaporation from the earth in these
+countries, and, of course, the humidity and the temperature of both the
+soil and the atmosphere in contact with it, must be much affected by the
+practice of irrigation. The cultivable area of Egypt, or the space
+accessible to cultivation, between desert and desert, is more than seven
+thousand square statute miles. Much of the surface, though not out of
+the reach of irrigation, lies too high to be economically watered, and
+irrigation and cultivation are therefore confined to an area of five or
+six thousand square miles, nearly the whole of which is regularly and
+constantly watered when not covered by the inundation, except in the
+short interval between the harvest and the rise of the waters. For
+nearly half of the year, then, irrigation adds five or six thousand
+square miles, or more than a square equatorial degree, to the evaporable
+surface of the Nile valley, or, in other words, more than decuples the
+area from which an appreciable quantity of moisture would otherwise be
+evaporated; for after the Nile has retired within its banks, its waters
+by no means cover one tenth of the space just mentioned.[334] The
+fresh-water canals now constructing, in connection with the works for
+the Suez canal, will not only restore the long abandoned fields east of
+the Nile, but add to the arable soil of Egypt hundreds of square miles
+of newly reclaimed desert, and thus still further increase the climatic
+effects of irrigation.[335]
+
+The Nile receives not a single tributary in its course through Egypt;
+there is not so much as one living spring in the whole land,[336] and,
+with the exception of a narrow strip of coast, where the annual
+precipitation is said to amount to six inches, the fall of rain in the
+territory of the Pharaohs is not two inches in the year. The subsoil of
+the whole valley is pervaded with moisture by infiltration from the
+Nile, and water can everywhere be found at the depth of a few feet. Were
+irrigation suspended, and Egypt abandoned, as in that case it must be,
+to the operations of nature, there is no doubt that trees, the roots of
+which penetrate deeply, would in time establish themselves on the
+deserted soil, fill the valley with verdure, and perhaps at last temper
+the climate, and even call down abundant rain from the heavens.[337] But
+the immediate effect of discontinuing irrigation would be, first, an
+immense reduction of the evaporation from the valley in the dry season,
+and then a greatly augmented dryness and heat of the atmosphere. Even
+the almost constant north wind--the strength of which would be increased
+in consequence of these changes--would little reduce the temperature of
+the narrow cleft between the burning mountains which hem in the channel
+of the Nile, so that a single year would transform the most fertile of
+soils to the most barren of deserts, and render uninhabitable a
+territory that irrigation makes capable of sustaining as dense a
+population as has ever existed in any part of the world.[338] Whether
+man found the valley of the Nile a forest, or such a waste as I have
+just described, we do not historically know. In either case, he has not
+simply converted a wilderness into a garden, but has unquestionably
+produced extensive climatic change.[339]
+
+The fields of Egypt are more regularly watered than those of any other
+country bordering on the Mediterranean, except the rice grounds in
+Italy, and perhaps the _marcite_ or winter meadows of Lombardy; but
+irrigation is more or less employed throughout almost the entire basin
+of that sea, and is everywhere attended with effects which, if less in
+degree, are analogous in character to those resulting from it in Egypt.
+In general, it may be said that the soil is nowhere artificially watered
+except when it is so dry that little moisture would be evaporated from
+it, and, consequently, every acre of irrigated ground is so much added
+to the evaporable surface of the country. When the supply of water is
+unlimited, it is allowed, after serving its purpose on one field, to run
+into drains, canals, or rivers. But in most regions where irrigation is
+regularly employed, it is necessary to economize the water; after
+passing over or through one parcel of ground, it is conducted to
+another; no more is withdrawn from the canals at any one point than is
+absorbed by the soil it irrigates, or evaporated from it, and,
+consequently, it is not restored to liquid circulation, except by
+infiltration or precipitation. We are safe, then, in saying that the
+humidity evaporated from any artificially watered soil is increased by a
+quantity bearing a large proportion to the whole amount distributed over
+it; for most even of that which is absorbed by the earth is immediately
+given out again either by vegetables or by evaporation.
+
+It is not easy to ascertain precisely either the extent of surface thus
+watered, or the amount of water supplied, in any given country, because
+these quantities vary with the character of the season; but there are
+not many districts in Southern Europe where the management of the
+arrangements for irrigation is not one of the most important branches of
+agricultural labor. The eminent engineer Lombardini describes the system
+of irrigation in Lombardy as, "every day in summer, diffusing over
+550,000 hectares of land 45,000,000 cubic metres of water, which is
+equal to the entire volume of the Seine, at an ordinary flood, or a rise
+of three metres above the hydrometer at the bridge of La Tournelle at
+Paris."[340] Niel states the quantity of land irrigated in the former
+kingdom of Sardinia, including Savoy, in 1856, at 240,000 hectares, or
+not much less than 600,000 acres. This is about four thirteenths of the
+cultivable soil of the kingdom. According to the same author, the
+irrigated lands in France did not exceed 100,000 hectares, or 247,000
+acres, while those in Lombardy amounted to 450,000 hectares, more than
+1,100,000 acres.[341] In these three states alone, then, there were more
+than three thousand square miles of artificially watered land, and if we
+add the irrigated soils of the rest of Italy, of the Mediterranean
+islands, of the Spanish peninsula, of Turkey in Europe and in Asia
+Minor, of Syria, of Egypt and the remainder of Northern Africa, we shall
+see that irrigation increases the evaporable surface of the
+Mediterranean basin by a quantity bearing no inconsiderable proportion
+to the area naturally covered by water within it. As near as can be
+ascertained, the amount of water applied to irrigated lands is scarcely
+anywhere less than the total precipitation during the season of
+vegetable growth, and in general it much exceeds that quantity. In grass
+grounds and in field culture it ranges from 27 or 28 to 60 inches, while
+in smaller crops, tilled by hand labor, it is sometimes carried as high
+as 300 inches.[342] The rice grounds and the _marcite_ of Lombardy are
+not included in these estimates of the amount of water applied.
+Arrangements are concluded, and new plans proposed, for an immense
+increase of the lands fertilized by irrigation in France and Italy, and
+there is every reason to believe that the artificially watered soil of
+the latter country will be doubled, that of France quadrupled, before
+the end of this century. There can be no doubt that by these operations
+man is exercising a powerful influence on soil, on vegetable and animal
+life, and on climate, and hence that in this, as in many other fields of
+industry, he is truly a geographical agency.[343] The quantity of water
+artificially withdrawn from running streams for the purpose of
+irrigation is such as very sensibly to affect their volume, and it is,
+therefore, an important element in the geography of rivers. Brooks of no
+trifling current are often wholly diverted from their natural channels
+to supply the canals, and their entire mass of water completely
+absorbed, so that it does not reach the river which it naturally feeds,
+except in such proportion as it is conveyed to it by infiltration.
+Irrigation, therefore, diminishes great rivers in warm countries by
+cutting off their sources of supply as well as by direct abstraction of
+water from their channels. We have just seen that the system of
+irrigation in Lombardy deprives the Po of a quantity of water equal to
+the total delivery of the Seine at ordinary flood, or, in other words,
+of the equivalent of a tributary navigable for hundreds of miles by
+vessels of considerable burden. The new canals commenced and projected
+will greatly increase the loss. The water required for irrigation in
+Egypt is less than would be supposed from the exceeding rapidity of
+evaporation in that arid climate; for the soil is thoroughly saturated
+during the inundation, and infiltration from the Nile continues to
+supply a considerable amount of humidity in the dryest season. Linant
+Bey computed that twenty-nine cubic metres per day sufficed to irrigate
+a hectare in the Delta.[344] This is equivalent to a fall of rain of two
+millimetres and nine tenths per day, or, if we suppose water to be
+applied for one hundred and fifty days during the dry season, to a total
+precipitation of 435 millimetres, about seventeen inches and one third.
+Taking the area of actually cultivated soil in Egypt at the low estimate
+of 3,600,000 acres, and the average amount of water daily applied in
+both Upper and Lower Egypt at twelve hundredths of an inch in depth, we
+have an abstraction of 61,000,000 cubic yards, which--the mean daily
+delivery of the Nile being in round numbers 320,000,000 cubic yards--is
+nearly one fifth of the average quantity of water contributed to the
+Mediterranean by that river.
+
+Irrigation, as employed for certain special purposes in Europe and
+America, is productive of very prejudicial climatic effects. I refer
+particularly to the cultivation of rice in the Slave States of the
+American Union and in Italy. The climate of the Southern States is not
+necessarily unhealthy for the white man, but he can scarcely sleep a
+single night in the vicinity of the rice grounds without being attacked
+by a dangerous fever.[345] The neighborhood of the rice fields is less
+pestilential in Lombardy and Piedmont than in South Carolina and
+Georgia, but still very insalubrious to both man and beast. "Not only
+does the population decrease where rice is grown," says Escourrou
+Milliago, "but even the flocks are attacked by typhus. In the rice
+grounds, the soil is divided into compartments rising in gradual
+succession to the level of the irrigating canal, in order that the
+water, after having flowed one field, may be drawn off to another, and
+thus a single current serve for several compartments, the lowest field,
+of course, still being higher than the ditch which at last drains both
+it and the adjacent soil. This arrangement gives a certain force of
+hydrostatic pressure to the water with which the rice is irrigated, and
+the infiltration from these fields is said to extend through neighboring
+grounds, sometimes to the distance of not less than a myriametre, or six
+English miles, and to be destructive to crops and even trees reached by
+it. Land thus affected can no longer be employed for any purpose but
+growing rice, and when prepared for that crop, it propagates still
+further the evils under which it had itself suffered, and, of course,
+the mischief is a growing one."[346]
+
+The attentive traveller in Egypt and Nubia cannot fail to notice many
+localities, generally of small extent, where the soil is rendered
+infertile by an excess of saline matter in its composition. In many
+cases, perhaps in all, these barren spots lie rather above the level
+usually flooded by the inundations of the Nile, and yet they exhibit
+traces of former cultivation. Recent observations in India, a notice of
+which I find in an account of a meeting of the Asiatic Society in the
+Athenaeum of December 20, 1862, No. 1834, suggest a possible explanation
+of this fact. At this meeting, Professor Medlicott read an essay on "the
+saline efflorescence called 'Reh' and 'Kuller,'" which is gradually
+invading many of the most fertile districts of Northern and Western
+India, and changing them into sterile deserts. It consists principally
+of sulphate of soda (Glauber's salts), with varying proportions of
+common salt. Mr. Medlicott pronounces "these salts (which, in small
+quantities are favorable to fertility of soil) to be the gradual result
+of concentration by evaporation of river and canal waters, which contain
+them in very minute quantities, and with which the lands are either
+irrigated or occasionally overflowed." The river inundations in hot
+countries usually take place but once in a year, and, though the banks
+remain submerged for days or even weeks, the water at that period, being
+derived principally from rains and snows, must be less highly charged
+with mineral matter than at lower stages, and besides, it is always in
+motion. The water of irrigation, on the other hand, is applied for many
+months in succession, it is drawn from rivers at the seasons when their
+proportion of salts is greatest, and it either sinks into the
+superficial soil, carrying with it the saline substances it holds in
+solution, or is evaporated from the surface, leaving them upon it. Hence
+irrigation must impart to the soil more salts than natural inundation.
+The sterilized grounds in Egypt and Nubia lying above the reach of the
+floods, as I have said, we may suppose them to have been first
+cultivated in that remote antiquity when the Nile valley received its
+earliest inhabitants. They must have been artificially irrigated from
+the beginning; they may have been under cultivation many centuries
+before the soil at a lower level was invaded by man, and hence it is
+natural that they should be more strongly impregnated with saline matter
+than fields which are exposed every year, for some weeks, to the action
+of running water so nearly pure that it would be more likely to dissolve
+salts than to deposit them.
+
+
+INUNDATIONS AND TORRENTS.
+
+In pointing out in a former chapter the evils which have resulted from
+the too extensive destruction of the forests, I dwelt at some length on
+the increased violence of river inundations, and especially on the
+devastations of torrents, in countries improvidently deprived of their
+woods, and I spoke of the replanting of the forests as the only
+effectual method of preventing the frequent recurrence of disastrous
+floods. There are many regions where, from the loss of the superficial
+soil, from financial considerations, and from other causes, the
+restoration of the woods is not, under present circumstances, to be
+hoped for. Even where that measure is feasible and in actual process of
+execution, a great number of years must elapse before the action of the
+destructive causes in question can be arrested or perhaps even sensibly
+mitigated by it. Besides this, leaving out of view the objections urged
+by Belgrand and his followers to the generally received opinions
+concerning the beneficial influence of the forest as respects river
+inundations--for no one disputes its importance in preventing the
+formation and limiting the ravages of mountain torrents--floods will
+always occur in years of excessive precipitation, whether the surface of
+the soil be generally cleared or generally wooded.
+
+Physical improvement in this respect, then, cannot he confined to
+preventive measures, but, in countries subject to damage by inundation,
+means must he contrived to obviate dangers and diminish injuries to
+which human life and all the works of human industry will occasionally
+be exposed, in spite of every effort to lessen the frequency of their
+recurrence by acting directly on the causes that produce them. As every
+civilized country is, in some degree, subject to inundation by the
+overflow of rivers, the evil is a familiar one, and needs no general
+description. In discussing this branch of the subject, therefore, I may
+confine myself chiefly to the means that have been or may be employed to
+resist the force and limit the ravages of floods, which, left wholly
+unrestrained, would not only inflict immense injury upon the material
+interests of man, but produce geographical revolutions of no little
+magnitude.
+
+
+a. _River Embankments._
+
+The most obvious and doubtless earliest method of preventing the escape
+of river waters from their natural channels, and the overflow of fields
+and towns by their spread, is that of raised embankments along their
+course. The necessity of such embankments usually arises from the
+gradual elevation of the bed of running streams in consequence of the
+deposit of the earth and gravel they are charged with in high water;
+and, as we have seen, this elevation is rapidly accelerated when the
+highlands around the headwaters of rivers are cleared of their forests.
+When a river is embanked at a given point, and, consequently, the water
+of its floods, which would otherwise spread over a wide surface, is
+confined within narrow limits, the velocity of the current and its
+transporting power are augmented, and its burden of sand and gravel is
+deposited at some lower point, where the rapidity of its flow is
+checked by a diminution in the inclination of the bed, by a wider
+channel, or finally by a lacustrine or marine basin which receives its
+waters. Wherever it lets fall solid material, its channel is raised in
+consequence, and the declivity of the whole bed between the head of the
+embankment and the slack of the stream is reduced. Hence the current, at
+first accelerated by confinement, is afterward checked by the mechanical
+resistance of the matter deposited, and by the diminished inclination of
+its channel, and then begins again to let fall the earth it holds in
+suspension, and to raise its bed at the point where its overflow had
+been before prevented by embankment. The bank must now be raised in
+proportion, and these processes would be repeated and repeated
+indefinitely, had not nature provided a remedy in floods, which sweep
+out recent deposits, burst the bonds of the river and overwhelm the
+adjacent country with final desolation, or divert the current into a new
+channel, destined to become, in its turn, the scene of a similar
+struggle between man and the waters.
+
+Few rivers, like the Nile, more than compensate by the fertilizing
+properties of their water and their slime for the damage they may do in
+inundations, and, consequently, there are few whose floods are not an
+object of dread, few whose encroachments upon their banks are not a
+source of constant anxiety and expense to the proprietors of the lands
+through which they flow. River dikes, for confining the spread of
+currents at high water, are of great antiquity in the East, and those of
+the Po and its tributaries were begun before we have any trustworthy
+physical or political annals of the provinces upon their borders. From
+the earliest ages, the Italian hydraulic engineers have stood in the
+front rank of their profession, and the Italian literature of this
+branch of material improvement is exceedingly voluminous. But the
+countries for which I write have no rivers like the Po, no plains like
+those of Lombardy, and the dangers to which the inhabitants of English
+and American river banks are exposed are more nearly analogous to those
+that threaten the soil and population in the valleys and plains of
+France, than to the perils and losses of the Lombard. The writings of
+the Italian hydrographers, too, though rich in professional instruction,
+are less accessible to foreigners and less adapted to popular use than
+those of French engineers.[347] For these reasons I shall take my
+citations principally from French authorities, though I shall
+occasionally allude to Italian writers on the floods of the Tiber, of
+the Arno, and some other Italian streams which much resemble those of
+the rivers of England and the United States.
+
+
+b. _Floods of the Ardeche._
+
+The floods of mountain streams are attended with greater immediate
+danger to life and property than those of rivers of less rapid flow,
+because their currents are more impetuous, and they rise more suddenly
+and with less previous warning. At the same time, their ravages are
+confined within narrower limits, the waters retire sooner to their
+accustomed channel, and the danger is more quickly over, than in the
+case of inundations of larger rivers. The Ardeche, which has given its
+name to a department in France, drains a basin of 600,238 acres, or a
+little less than nine hundred and thirty-eight square miles. Its
+remotest source is about seventy-five miles, in a straight line, from
+its junction with the Rhone, and springs at an elevation of four
+thousand feet above that point. At the lowest stage of the river, the
+bed of the Chassezac, its largest and longest tributary, is in many
+places completely dry on the surface--the water being sufficient only
+to supply the subterranean channels of infiltration--and the Ardeche
+itself is almost everywhere fordable, even below the mouth of the
+Chassezac. But in floods, the river has sometimes risen more than sixty
+feet at the Pont d'Arc, a natural arch of two hundred feet chord, which
+spans the stream below its junction with all its important affluents. At
+the height of the inundation of 1827, the quantity of water passing this
+point--after deducting thirty per cent. for material transported with
+the current and for irregularity of flow--was estimated at 8,845 cubic
+yards to the second, and between twelve at noon on the 10th of September
+of that year and ten o'clock the next morning, the water discharged
+through the passage in question amounted to more than 450,000,000 cubic
+yards. This quantity, distributed equally through the basin of the
+river, would cover its entire area to a depth of more than five inches.
+
+The Ardeche rises so suddenly that, in the inundation of 1846, the women
+who were washing in the bed of the river had not time to save their
+linen, and barely escaped with their lives, though they instantly fled
+upon hearing the roar of the approaching flood. Its waters and those of
+its affluents fall almost as rapidly, for in less than twenty-four hours
+after the rain has ceased in the Cevennes, where it rises, the Ardeche
+returns within its ordinary channel, even at its junction with the
+Rhone. In the flood of 1772, the water at La Beaume de Ruoms, on the
+Beaume, a tributary of the Ardeche, rose thirty-five feet above low
+water, but the stream was again fordable on the evening of the same day.
+The inundation of 1827 was, in this respect, exceptional, for it
+continued three days, during which period the Ardeche poured into the
+Rhone 1,305,000,000 cubic yards of water.
+
+The Nile delivers into the sea 101,000 cubic feet or 3,741 cubic yards
+per second, on an average of the whole year.[348] This is equal to
+323,222,400 cubic yards per day. In a single day of flood, then, the
+Ardeche, a river too insignificant to be known except in the local
+topography of France, contributed to the Rhone once and a half, and for
+three consecutive days once and one third, as much as the average
+delivery of the Nile during the same periods, though the basin of the
+latter river contains 500,000 square miles of surface, or more than five
+hundred times as much as that of the former.
+
+The average annual precipitation in the basin of the Ardeche is not
+greater than in many other parts of Europe, but excessive quantities of
+rain frequently fall in that valley in the autumn. On the 9th of
+October, 1827, there fell at Joyeuse, on the Beaume, no less than
+thirty-one inches between three o'clock in the morning and midnight.
+Such facts as this explain the extraordinary suddenness and violence of
+the floods of the Ardeche, and the basins of many other tributaries of
+the Rhone exhibit meteorological phenomena not less remarkable.[349] The
+inundation of the 10th September, 1857, was accompanied with a terrific
+hurricane, which passed along the eastern slope of the high grounds
+where the Ardeche and several other western affluents of the Rhone take
+their rise. The wind tore up all the trees in its path, and the rushing
+torrents bore their trunks down to the larger streams, which again
+transported them to the Rhone in such rafts that one might almost have
+crossed that river by stepping from trunk to trunk.[350] The Rhone,
+therefore, is naturally subject to great and sudden inundations, and the
+same remark may be applied to most of the principal rivers of France,
+because the geographical character of all of them is approximately the
+same.
+
+The height and violence of the inundations of most great rivers are
+determined by the degree in which the floods of the different
+tributaries are coincident in time. Were all the affluents of the Rhone
+to pour their highest annual floods into its channel at once, were a
+dozen Niles to empty themselves into its bed at the same moment, its
+water would rise to a height and rush with an impetus that would sweep
+into the Mediterranean the entire population of its banks, and all the
+works that man has erected upon the plains which border it. But such a
+coincidence can never happen. The tributaries of this river run in very
+different directions, and some of them are swollen principally by the
+melting of the snows about their sources, others almost exclusively by
+heavy rains. When a damp southeast wind blows up the valley of the
+Ardeche, its moisture is condensed, and precipitated in a deluge upon
+the mountains which embosom the headwaters of that stream, thus
+producing a flood, while a neighboring basin, the axis of which lies
+transversely or obliquely to that of the Ardeche, is not at all
+affected.[351]
+
+It is easy to see that the damage occasioned by such floods as I have
+described must be almost incalculable, and it is by no means confined to
+the effects produced by overflow and the mechanical force of the
+superficial currents. In treating of the devastations of torrents in a
+former chapter, I confined myself principally to the erosion of surface
+and the transportation of mineral matter to lower grounds by them. The
+general action of torrents, as there shown, tends to the ultimate
+elevation of their beds by the deposit of the earth, gravel, and stone
+conveyed by them; but until they have thus raised their outlets so as
+sensibly to diminish the inclination of their channels--and sometimes
+when extraordinary floods give the torrents momentum enough to sweep
+away the accumulations which they have themselves heaped up--the swift
+flow of their currents, aided by the abrasion of the rolling rocks and
+gravel, scoops their beds constantly deeper, and they consequently not
+only undermine their banks, but frequently sap the most solid
+foundations which the art of man can build for the support of bridges
+and hydraulic structures.[352]
+
+In the inundation of 1857, the Ardeche destroyed a stone bridge near La
+Beaume, which had been built about eighty years before. The resistance
+of the piers, which were erected on piles, the channel at that point
+being of gravel, produced an eddying current that washed away the bed of
+the river above them, and the foundation, thus deprived of lateral
+support, yielded to the weight of the bridge, and the piles and piers
+fell up stream.
+
+By a curious law of compensation, the stream which, at flood, scoops out
+cavities in its bed, often fills them up again as soon as the diminished
+velocity of the current allows it to let fall the sand and gravel with
+which it is charged, so that when the waters return to their usual
+channel, the bottom shows no sign of having been disturbed. In a flood
+of the Escontay, a tributary of the Rhone, in 1846, piles driven sixteen
+feet into its gravelly bed for the foundation of a pier were torn up and
+carried off, and yet, when the river had fallen to low-water mark, the
+bottom at that point appeared to have been raised higher than it was
+before the flood, by new deposits of sand and gravel, while the cut
+stones of the half-built pier were found buried to a great depth, in the
+excavation which the water had first washed out. The gravel with which
+rivers thus restore the level of their beds is principally derived from
+the crushing of the rocks brought down by the mountain torrents, and the
+destructive effects of inundations are immensely diminished by this
+reduction of large stones to minute fragments. If the blocks hurled down
+from the cliffs were transported unbroken to the channels of large
+rivers, the mechanical force of their movement would be irresistible.
+They would overthrow the strongest barriers, spread themselves over a
+surface as wide as the flow of the waters, and convert the most smiling
+valleys into scenes of the wildest desolation.
+
+
+c. _Crushing Force of Torrents._
+
+There are few operations of nature where the effect seems more
+disproportioned to the cause than in the comminution of rock in the
+channel of swift waters. Igneous rocks are generally so hard as to be
+wrought with great difficulty, and they bear the weight of enormous
+superstructures without yielding to the pressure; but to the torrent
+they are as wheat to the millstone. The streams which pour down the
+southern scarp of the Mediterranean Alps along the Riviera di Ponente,
+near Genoa, have short courses, and a brisk walk of a couple of hours or
+even less takes you from the sea beach to the headspring of many of
+them. In their heaviest floods, they bring rounded masses of serpentine
+quite down to the sea, but at ordinary high water their lower course is
+charged only with finely divided particles of that rock. Hence, while,
+near their sources, their channels are filled with pebbles and angular
+fragments, intermixed with a little gravel, the proportions are reversed
+near their mouths, and, just above the points where their outlets are
+partially choked by the rolling shingle of the beach, their beds are
+composed of sand and gravel to the almost total exclusion of pebbles.
+The greatest depth of the basin of the Ardeche is seventy-five miles,
+but most of its tributaries have a much shorter course. "These
+affluents," says Mardigny, "hurl into the bed of the Ardeche enormous
+blocks of rock, which this river, in its turn, bears onward, and grinds
+down, at high water, so that its current rolls only gravel at its
+confluence with the Rhone."[353]
+
+Guglielmini argued that the gravel and sand of the beds of running
+streams were derived from the trituration of rocks by the action of the
+currents, and inferred that this action was generally sufficient to
+reduce hard rock to sand in its passage from the source to the outlet of
+rivers. Frisi controverted this opinion, and maintained that river sand
+was of more ancient origin, and he inferred from experiments in
+artificially grinding stones that the concussion, friction, and
+attrition of rock in the channel of running waters were inadequate to
+its comminution, though he admitted that these same causes might reduce
+silicious sand to a fine powder capable of transportation to the sea by
+the currents.[354] Frisi's experiments were tried upon rounded and
+polished river pebbles, and prove nothing with regard to the action of
+torrents upon the irregular, more or less weathered, and often cracked
+and shattered rocks which lie loose in the ground at the head of
+mountain valleys. The fury of the waters and of the wind which
+accompanies them in the floods of the French Alpine torrents is such,
+that large blocks of stone are hurled out of the bed of the stream to
+the height of twelve or thirteen feet. The impulse of masses driven with
+such force overthrows the most solid masonry, and their concussion
+cannot fail to be attended with the crushing of the rocks
+themselves.[355]
+
+
+d. _Inundations of 1856 in France._
+
+The month of May, 1856, was remarkable for violent and almost
+uninterrupted rains, and most of the river basins of France were
+inundated to an extraordinary height. In the valleys of the Loire and
+its affluents, about a million of acres, including many towns and
+villages, were laid under water, and the amount of pecuniary damage was
+almost incalculable.[356] The flood was not less destructive in the
+valley of the Rhone, and in fact an invasion by a hostile army could
+hardly have been more disastrous to the inhabitants of the plains than
+was this terrible deluge. There had been a flood of this latter river in
+the year 1840, which, for height and quantity of water, was almost as
+remarkable as that of 1856, but it took place in the month of November,
+when the crops had all been harvested, and the injury inflicted by it
+upon agriculturists was, therefore, of a character to be less severely
+and less immediately felt than the consequences of the inundation of
+1856.[357]
+
+In the fifteen years between these two great floods, the population and
+the rural improvements of the river valleys had much increased, common
+roads, bridges, and railways had been multiplied and extended, telegraph
+lines had been constructed, all of which shared in the general ruin, and
+hence greater and more diversified interests were affected by the
+catastrophe of 1856 than by any former like calamity. The great flood of
+1840 had excited the attention and roused the sympathies of the French
+people, and the subject was invested with new interest by the still more
+formidable character of the inundations of 1856. It was felt that these
+scourges had ceased to be a matter of merely local concern, for,
+although they bore most heavily on those whose homes and fields were
+situated within the immediate reach of the swelling waters, yet they
+frequently destroyed harvests valuable enough to be a matter of national
+interest, endangered the personal security of the population of
+important political centres, interrupted communication for days and even
+weeks together on great lines of traffic and travel--thus severing as
+it were all Southwestern France from the rest of the empire--and finally
+threatened to produce great and permanent geographical changes. The
+well-being of the whole commonwealth was seen to be involved in
+preventing the recurrence, and in limiting the range of such
+devastations. The Government encouraged scientific investigation of the
+phenomena and their laws. Their causes, their history, their immediate
+and remote consequences, and the possible safeguards to be employed
+against them, have been carefully studied by the most eminent
+physicists, as well as by the ablest theoretical and practical engineers
+of France. Many hitherto unobserved facts have been collected, many new
+hypotheses suggested, and many plans, more or less original in
+character, have been devised for combating the evil; but thus far, the
+most competent judges are not well agreed as to the mode, or even the
+possibility, of applying a remedy.
+
+
+e. _Remedies against Inundations._
+
+Perhaps no one point has been more prominent in the discussions than the
+influence of the forest in equalizing and regulating the flow of the
+water of precipitation. As we have already seen, opinion is still
+somewhat divided on this subject, but the conservative action of the
+woods in this respect has been generally recognized by the public of
+France, and the Government of the empire has made this principle the
+basis of important legislation for the protection of existing forests,
+and for the formation of new. The clearing of woodland, and the
+organization and functions of a police for its protection, are regulated
+by a law bearing date June 18th, 1859, and provision was made for
+promoting the restoration of private woods by a statute adopted on the
+28th of July, 1860. The former of these laws passed the legislative body
+by a vote of 246 against 4, the latter with but a single negative voice.
+The influence of the government, in a country where the throne is so
+potent as in France, would account for a large majority, but when it is
+considered that both laws, the former especially, interfere very
+materially with the rights of private domain, the almost entire
+unanimity with which they were adopted is proof of a very general
+popular conviction, that the protection and extension of the forests is
+a measure more likely than any other to check the violence, if not to
+prevent the recurrence, of destructive inundations. The law of July
+28th, 1860, appropriated 10,000,000 francs, to be expended, at the rate
+of 1,000,000 francs per year, in executing or aiding the replanting of
+woods. It is computed that this appropriation will secure the creation
+of new forest to the extent of about 250,000 acres, or one eleventh part
+of the soil where the restoration of the forest is thought feasible and,
+at the same time, specially important as a security against the evils
+ascribed in a great measure to its destruction.
+
+The provisions of the laws in question are preventive rather than
+remedial; but some immediate effect may be expected to result from them,
+particularly if they are accompanied with certain other measures, the
+suggestion of which has been favorably received. The strong repugnance
+of the mountaineers to the application of a system which deprives them
+of a part of their pasturage--for the absolute exclusion of domestic
+animals is indispensable to the maintenance of an existing forest and to
+the formation of a new--is the most formidable obstacle to the execution
+of the laws of 1859-'60. It is proposed to compensate this loss by a
+cheap system of irrigation of lower pasture grounds, consisting in
+little more than in running horizontal furrows along the hillsides, thus
+converting the scarp of the hills into a succession of small terraces
+which, when once turfed over, are very permanent. Experience is said to
+have demonstrated that this simple process suffices to retain the water
+of rains, of snows, and of small springs and rivulets, long enough for
+the irrigation of the soil, thus increasing its product of herbage in a
+fivefold proportion, and that it partially checks the too rapid flow of
+surface water into the valleys, and, consequently, in some measure
+obviates one of the most prominent causes of inundations.[358] It is
+evident that, if such results are produced by this method, its
+introduction upon an extensive scale must also have the same climatic
+effects as other systems of irrigation.
+
+Whatever may be the ultimate advantages of reclothing a large extent of
+the territory of France with wood, or of so shaping its surface as to
+prevent the too rapid flow of water over it, the results to be obtained
+by such processes can be realized in an adequate measure only after a
+long succession of years. Other steps must be taken, both for the
+immediate security of the lives and property of the present generation,
+and for the prevention of yet greater and remoter evils which are
+inevitable unless means to obviate them are found before it is forever
+too late. The frequent recurrence of inundations like those of 1856, for
+a single score of years, in the basins of the Rhone and the Loire, with
+only the present securities against them, would almost depopulate the
+valleys of those rivers, and produce physical revolutions in them,
+which, like revolutions in the political world, could never be made to
+"go backward."
+
+Destructive inundations are seldom, if ever, produced by precipitation
+within the limits of the principal valley, but almost uniformly by
+sudden thaws or excessive rains on the mountain ranges where the
+tributaries take their rise. It is therefore plain that any measures
+which shall check the flow of surface waters into the channels of the
+affluents, or which shall retard the delivery of such waters into the
+principal stream by its tributaries, will diminish in the same
+proportion the dangers and the evils of inundation by great rivers. The
+retention of the surface waters upon or in the soil can hardly be
+accomplished except by the methods already mentioned, replanting of
+forests, and furrowing or terracing. The current of mountain streams can
+be checked by various methods, among which the most familiar and obvious
+is the erection of barriers or dams across their channels, at points
+convenient for forming reservoirs large enough to retain the superfluous
+waters of great rains and thaws. Besides the utility of such basins in
+preventing floods, the construction of them is recommended by very
+strong considerations, such as the meteorological effects of increased
+evaporable surface, the furnishing of a constant supply of water for
+agricultural and mechanical purposes, and, finally, their value as ponds
+for breeding and rearing fish, and, perhaps, for cultivating aquatic
+vegetables.
+
+The objections to the general adoption of the system of reservoirs are
+these: the expense of their construction and maintenance; the reduction
+of cultivable area by the amount of surface they must cover; the
+interruption they would occasion to free communication; the probability
+that they would soon be filled up with sediment, and the obvious fact
+that when full of earth or even water, they would no longer serve their
+principal purpose; the great danger to which they would expose the
+country below them in case of the bursting of their barriers;[359] the
+evil consequences they would occasion by prolonging the flow of
+inundations in proportion as they diminished their height; the injurious
+effects it is supposed they would produce upon the salubrity of the
+neighboring districts; and, lastly, the alleged impossibility of
+constructing artificial basins sufficient in capacity to prevent, or in
+any considerable measure to mitigate, the evils they are intended to
+guard against.
+
+The last argument is more easily reduced to a numerical question than
+the others. The mean and extreme annual precipitation of all the basins
+where the construction of such works would be seriously proposed is
+already approximately known by meteorological tables, and the quantity
+of water, delivered by the greatest floods which have occurred within
+the memory of man, may be roughly estimated from their visible traces.
+From these elements, or from recorded observations, the capacity of the
+necessary reservoirs can be calculated. Let us take the case of the
+Ardeche. In the inundation of 1857, that river poured into the Rhone
+1,305,000,000 cubic yards of water in three days. If we suppose that
+half this quantity might have been suffered to flow down its channel
+without inconvenience, we shall have about 650,000,000 cubic yards to
+provide for by reservoirs. The Ardeche and its principal affluent, the
+Chassezac, have, together, about twelve considerable tributaries rising
+near the crest of the mountains which bound the basin. If reservoirs of
+equal capacity were constructed upon all of them, each reservoir must be
+able to contain 54,000,000 cubic yards, or, in other words, must be
+equal to a lake 3,000 yards long, 1,000 yards wide, and 18 yards deep,
+and besides, in order to render any effectual service, the reservoirs
+must all have been empty at the commencement of the rains which produced
+the inundation.
+
+Thus far, I have supposed the swelling of the waters to be uniform
+throughout the whole basin; but such was by no means the fact in the
+inundation of 1857, for the rise of the Chassezac, which is as large as
+the Ardeche proper, did not exceed the limits of ordinary floods, and
+the dangerous excess came solely from the headwaters of the latter
+stream. Hence reservoirs of double the capacity I have supposed would
+have been necessary upon the tributaries of that river, to prevent the
+injurious effects of the inundation. It is evident that the construction
+of reservoirs of such magnitude for such a purpose is financially, if
+not physically, impracticable, and when we take into account a point I
+have just suggested, namely, that the reservoirs must be empty at all
+times of apprehended flood, and, of course, their utility limited almost
+solely to the single object of preventing inundations, the total
+inapplicability of such a measure in this particular case becomes still
+more glaringly manifest.
+
+Another not less conclusive fact is that the valleys of all the upland
+tributaries of the Ardeche descend so rapidly, and have so little
+lateral expansion, as to render the construction of capacious reservoirs
+in them quite impracticable. Indeed, engineers have found but two points
+in the whole basin suitable for that purpose, and the reservoirs
+admissible at these would have only a joint capacity of about 70,000,000
+cubic yards, or less than one ninth part of what I suppose to be
+required. The case of the Ardeche is no doubt an extreme one, both in
+the topographical character of its basin and in its exposure to
+excessive rains; but all destructive inundations are, in a certain
+sense, extreme cases also, and this of the Ardeche serves to show that
+the construction of reservoirs is not by any means to be regarded as a
+universal panacea against floods.
+
+Nor, on the other hand, is this measure to be summarily rejected. Nature
+has adopted it on a great scale, on both flanks of the Alps, and on a
+smaller, on those of the Adirondacks and lower chains, and in this as in
+many other instances, her processes may often be imitated with
+advantage. The validity of the remaining objections to the system under
+discussion depends on the topography, geology, and special climate of
+the regions where it is proposed to establish such reservoirs. Many
+upland streams present numerous points where none of these objections,
+except those of expense and of danger from the breaking of dams, could
+have any application. Reservoirs may be so constructed as to retain the
+entire precipitation of the heaviest thaws and rains, leaving only the
+ordinary quantity to flow along the channel; they may be raised to such
+a height as only partially to obstruct the surface drainage; or they may
+be provided with sluices by means of which their whole contents can be
+discharged in the dry season and a summer crop be grown upon the ground
+they cover at high water. The expediency of employing them and the mode
+of construction depend on local conditions, and no rules of universal
+applicability can be laid down on the subject.
+
+It is remarkable that nations which we, in the false pride of our modern
+civilization, so generally regard as little less than barbarian, should
+have long preceded Christian Europe in the systematic employment of
+great artificial basins for the various purposes they are calculated to
+subserve. The ancient Peruvians built strong walls, of excellent
+workmanship, across the channels of the mountain sources of important
+streams, and the Arabs executed immense works of similar description,
+both in the great Arabian peninsula and in all the provinces of Spain
+which had the good fortune to fall under their sway. The Spaniards of
+the fifteenth and sixteenth centuries, who, in many points of true
+civilization and culture, were far inferior to the races they subdued,
+wantonly destroyed these noble monuments of social and political wisdom,
+or suffered them to perish, because they were too ignorant to appreciate
+their value, or too unskilful as practical engineers to be able to
+maintain them, and some of their most important territories were soon
+reduced to sterility and poverty in consequence.
+
+Another method of preventing or diminishing the evils of inundation by
+torrents and mountain rivers, analogous to that employed for the
+drainage of lakes, consists in the permanent or occasional diversion of
+their surplus waters, or of their entire currents, from their natural
+courses, by tunnels or open channels cut through their banks. Nature, in
+many cases, resorts to a similar process. Most great rivers divide
+themselves into several arms in their lower course, and enter the sea by
+different mouths. There are also cases where rivers send off lateral
+branches to convey a part of their waters into the channel of other
+streams.[360] The most remarkable of these is the junction between the
+Amazon and the Orinoco by the natural canal of the Cassiquiare and the
+Rio Negro. In India, the Cambodja and the Menam are connected by the
+Anam; the Saluen and the Irawaddi by the Panlaun. There are similar
+examples, though on a much smaller scale, in Europe. The Tornea and the
+Calix rivers in Lapland communicate by the Tarando, and in Westphalia,
+the Else, an arm of the Haase, falls into the Weser.
+
+The change of bed in rivers by gradual erosion of their banks is
+familiar to all, but instances of the sudden abandonment of a primitive
+channel are by no means wanting. At a period of unknown antiquity, the
+Ardeche pierced a tunnel 200 feet wide and 100 high, through a rock, and
+sent its whole current through it, deserting its former bed, which
+gradually filled up, though its course remained traceable. In the great
+inundation of 1827, the tunnel proved insufficient for the discharge of
+the water, and the river burst through the obstructions which had now
+choked up its ancient channel, and resumed its original course.[361]
+
+It was probably such facts as these that suggested to ancient engineers
+the possibility of like artificial operations, and there are numerous
+instances of the execution of works for this purpose in very remote
+ages. The Bahr Jusef, the great stream which supplies the Fayoum with
+water from the Nile, has been supposed, by some writers, to be a natural
+channel; but both it and the Bahr el Wady are almost certainly
+artificial canals constructed to water that basin, to regulate the level
+of Lake Moeris, and possibly, also, to diminish the dangers resulting
+from excessive inundations of the Nile, by serving as waste-weirs to
+discharge a part of its surplus waters. Several of the seven ancient
+mouths of the Nile are believed to be artificial channels, and Herodotus
+even asserts that King Menes diverted the entire course of that river
+from the Libyan to the Arabian side of the valley. There are traces of
+an ancient river bed along the western mountains, which give some
+countenance to this statement. But it is much more probable that the
+works of Menes were designed rather to prevent a natural, than to
+produce an artificial, change in the channel of the river.
+
+Two of the most celebrated cascades in Europe, those of the Teverone at
+Tivoli and of the Velino at Terni, owe, if not their existence, at least
+their position and character, to the diversion of their waters from
+their natural beds into new channels, in order to obviate the evils
+produced by their frequent floods. Remarkable works of the same sort
+have been executed in Switzerland, in very recent times. Until the year
+1714, the Kander, which drains several large Alpine valleys, ran, for a
+considerable distance, parallel with the Lake of Thun, and a few miles
+below the city of that name emptied into the river Aar. It frequently
+flooded the flats along the lower part of its course, and it was
+determined to divert it into the Lake of Thun. For this purpose, two
+parallel tunnels were cut through the intervening rock, and the river
+turned into them. The violence of the current burst up the roof of the
+tunnels, and, in a very short time, wore the new channel down not less
+than one hundred feet, and even deepened the former bed at least fifty
+feet, for a distance of two or three miles above the tunnel. The lake
+was two hundred feet deep at the point where the river was conducted
+into it, but the gravel and sand carried down by the Kander has formed
+at its mouth a delta containing more than a hundred acres, which is
+still advancing at the rate of several yards a year. The Linth, which
+formerly sent its waters directly to the Lake of Zurich, and often
+produced very destructive inundations, was turned into the Wallensee
+about forty years ago, and in both these cases a great quantity of
+valuable land was rescued both from flood and from insalubrity.
+
+In Switzerland, the most terrible inundations often result from the
+damming up of deep valleys by ice slips or by the gradual advance of
+glaciers, and the accumulation of great masses of water above the
+obstructions. The ice is finally dissolved by the heat of summer or the
+flow of warm waters, and when it bursts, the lake formed above is
+discharged almost in an instant, and all below is swept down to certain
+destruction. In 1595, about a hundred and fifty lives and a great amount
+of property were lost by the eruption of a lake formed by the descent of
+a glacier into the valley of the Drance, and a similar calamity laid
+waste a considerable extent of soil in the year 1818. On this latter
+occasion, the barrier of ice and snow was 3,000 feet long, 600 thick,
+and 400 high, and the lake which had formed above it contained not less
+than 800,000,000 cubic feet. A tunnel was driven through the ice, and
+about 300,000,000 cubic feet of water safely drawn off by it, but the
+thawing of the walls of the tunnel rapidly enlarged it, and before the
+lake was half drained, the barrier gave way and the remaining
+500,000,000 cubic feet of water were discharged in half an hour. The
+recurrence of these floods has since been prevented by directing streams
+of water, warmed by the sun, upon the ice in the bed of the valley, and
+thus thawing it before it accumulates in sufficient mass to threaten
+serious danger.
+
+In the cases of diversion of streams above mentioned, important
+geographical changes have been directly produced by those operations. By
+the rarer process of draining glacier lakes, natural eruptions of water,
+which would have occasioned not less important changes in the face of
+the earth, have been prevented by human agency.
+
+The principal means hitherto relied upon for defence against river
+inundations has been the construction of dikes along the banks of the
+streams, parallel to the channel and generally separated from each other
+by a distance not much greater than the natural width of the bed.[362]
+If such walls are high enough to confine the water and strong enough to
+resist its pressure, they secure the lands behind them from all the
+evils of inundation except those resulting from infiltration; but such
+ramparts are enormously costly in original construction and maintenance,
+and, as we have already seen, the filling up of the bed of the river in
+its lower course, by sand and gravel, involves the necessity of
+occasionally incurring new expenditures in increasing the height of the
+banks.[363] They are attended, too, with some collateral disadvantages.
+They deprive the earth of the fertilizing deposits of the waters, which
+are powerful natural restoratives of soils exhausted by cultivation;
+they accelerate the rapidity and transporting power of the current at
+high water by confining it to a narrower channel, and it consequently
+conveys to the sea the earthy matter it holds in suspension, and chokes
+up harbors with a deposit which it would otherwise have spread over a
+wide surface; they interfere with roads and the convenience of river
+navigation, and no amount of cost or care can secure them from
+occasional rupture, in case of which the rush of the waters through the
+breach is more destructive than the natural flow of the highest
+inundation.[364]
+
+For these reasons, many experienced engineers are of opinion that the
+system of longitudinal dikes ought to be abandoned, or, where that
+cannot be done without involving too great a sacrifice of existing
+constructions, their elevation should be much reduced, so as to present
+no obstruction to the lateral spread of extraordinary floods, and they
+should be provided with sluices to admit the water without violence
+whenever they are likely to be overflowed. Where dikes have not been
+erected, and where they have been reduced in height, it is proposed to
+construct, at convenient intervals, transverse embankments of moderate
+height running from the banks of the river across the plains to the
+hills which bound them. These measures, it is argued, will diminish the
+violence of inundations by permitting the waters to extend themselves
+over a greater surface and thus retarding the flow of the river
+currents, and will, at the same time, secure the deposit of fertilizing
+slime upon all the soil covered by the flood.
+
+Rozet, an eminent French engineer, has proposed a method of diminishing
+the ravages of inundations, which aims to combine the advantages of all
+other systems, and at the same time to obviate the objections to which
+they are all more or less liable.[365] The plan of Rozet is recommended
+by its simplicity and cheapness as well as its facility and rapidity of
+execution, and is looked upon with favor by many persons very competent
+to judge in such matters. He proposes to commence with the amphitheatres
+in which mountain torrents so often rise, by covering their slopes and
+filling their beds with loose blocks of rock, and by constructing at
+their outlets, and at other narrow points in the channels of the
+torrents, permeable barriers of the same material promiscuously heaped
+up, much according to the method employed by the ancient Romans in their
+northern provinces for a similar purpose. By this means, he supposes,
+the rapidity of the current would be checked, and the quantity of
+transported pebbles and gravel much diminished.
+
+When the stream has reached that part of its course where it is bordered
+by soil capable of cultivation, and worth the expense of protection, he
+proposes to place along one or both sides of the stream, according to
+circumstances, a line of cubical blocks of stone or pillars of masonry
+three or four feet high and wide, and at the distance of about eleven
+yards from each other. The space between the two lines, or between a
+line and the opposite high bank, would, of course, be determined by
+observation of the width of the swift-water current at high floods. As
+an auxiliary measure, small ditches and banks, or low walls of pebbles,
+should be constructed from the line of blocks across the grounds to be
+protected, nearly at right angles to the current, but slightly inclining
+downward, and at convenient distances from each other. Rozet thinks the
+proper interval would be 300 yards, and it is evident that, if he is
+right in his main principle, hedges, rows of trees, or even common
+fences, would in many cases answer as good a purpose as banks and
+trenches or low walls. The blocks or pillars of stone would, he
+contends, check the lateral currents so as to compel them to let fall
+all their pebbles and gravel in the main channel--where they would be
+rolled along until ground down to sand or silt--and the transverse
+obstructions would detain the water upon the soil long enough to secure
+the deposit of its fertilizing slime. Numerous facts are cited in
+support of the author's views, and I imagine there are few residents of
+rural districts whose own observation will not furnish testimony
+confirmatory of their soundness.[366]
+
+The deposit of slime by rivers upon the flats along their banks not only
+contributes greatly to the fertility of the soil thus flowed, but it
+subserves a still more important purpose in the general economy of
+nature. All running streams begin with excavating channels for
+themselves, or deepening the natural depressions in which they
+flow;[367] but in proportion as their outlets are raised by the solid
+material transported by their currents, their velocity is diminished,
+they deposit gravel and sand at constantly higher and higher points, and
+so at last elevate, in the middle and lower part of their course, the
+beds they had previously scooped out.[368] The raising of the channels
+is compensated in part by the simultaneous elevation of their banks and
+the flats adjoining them, from the deposit of the finer particles of
+earth and vegetable mould brought down from the mountains, without which
+elevation the low grounds bordering all rivers would be, as in many
+cases they in fact are, mere morasses.
+
+All arrangements which tend to obstruct this process of raising the
+flats adjacent to the channel, whether consisting in dikes which confine
+the waters, and, at the same time, augment the velocity of the current,
+or in other means of producing the last-mentioned effect, interfere with
+the restorative economy of nature, and at last occasion the formation of
+marshes where, if left to herself, she would have accumulated
+inexhaustible stores of the richest soil, and spread them out in plains
+above the reach of ordinary floods.[369]
+
+
+_Consequences if the Nile had been Diked._
+
+If a system of continuous lateral dikes, like those of the Po, had been
+adopted in Egypt in the early dynasties, when the power and the will to
+undertake the most stupendous material enterprises were so eminently
+characteristic of the government of that country, and the waters of the
+annual inundation consequently prevented from flooding the land, it is
+conceivable that the productiveness of the small area of cultivable soil
+in the Nile valley might have been long kept up by artificial irrigation
+and the application of manures. But nature would have rebelled at last,
+and centuries before our time the mighty river would have burst the
+fetters by which impotent man had vainly striven to bind his swelling
+floods, the fertile fields of Egypt would have been converted into dank
+morasses, and then, perhaps, in some distant future, when the expulsion
+of man should have allowed the gradual restoration of the primitive
+equilibrium, would be again transformed into luxuriant garden and plough
+land. Fortunately, the "wisdom of Egypt" taught her children better
+things. They invited and welcomed, not repulsed, the slimy embraces of
+Nilus, and his favors have been, from the hoariest antiquity, the
+greatest material blessing ever bestowed upon a people.[370]
+
+The valley of the Po has probably not been cultivated or inhabited so
+long as that of the Nile, but embankments have been employed on its
+lower course for at least two thousand years, and for many centuries
+they have been connected in a continuous chain. I have pointed out in a
+former chapter the effects produced on the geography of the Adriatic by
+the deposit of river sediment in the sea at the mouths of the Po, the
+Adige, and the Brenta. If these rivers had been left unconfined, like
+the Nile, and allowed to spread their muddy waters at will, according to
+the laws of nature, the slime they have carried to the coast would have
+been chiefly distributed over the plains of Lombardy. Their banks would
+have risen as fast as their beds, the coast line would not have been
+extended so far into the Adriatic, and, the current of the streams being
+consequently shorter, the inclination of their channel and the rapidity
+of their flow would not have been so greatly diminished. Had man spared
+a reasonable proportion of the forests of the Alps, and not attempted to
+control the natural drainage of the surface, the Po would resemble the
+Nile in all its essential characteristics, and, in spite of the
+difference of climate, perhaps be regarded as the friend and ally, not
+the enemy and the invader, of the population which dwells upon its
+banks.[371]
+
+The Nile is larger than all the rivers of Lombardy together,[372] it
+drains a basin twenty times as extensive, its banks have been occupied
+by man probably twice as long. But its geographical character has not
+been much changed in the whole period of recorded history, and, though
+its outlets have somewhat fluctuated in number and position, its
+historically known encroachments upon the sea are trifling compared with
+those of the Po and the neighboring streams. The deposits of the Nile
+are naturally greater in Upper than in Lower Egypt. They are found to
+have raised the soil at Thebes about seven feet within the last
+seventeen hundred years, and in the Delta the rise has been certainly
+more than half as great.
+
+We shall, therefore, not exceed the truth if we suppose the annually
+inundated surface of Egypt to have been elevated, upon an average, ten
+feet, within the last 5,000 years, or twice and a half the period during
+which the history of the Po is known to us.[373]
+
+We may estimate the present actually cultivated area of Egypt at about
+5,500 square statute miles. As I have computed in a note on page 372,
+that area is not more than half as extensive as under the dynasties of
+the Pharaohs and the Ptolemies; for--though, in consequence of the
+elevation of the river bed, the inundations now have a wider _natural_
+spread--the industry of the ancient Egyptians conducted the Nile water
+over a great extent of soil it does not now reach. We may, then, adopt a
+mean between the two quantities, and we shall probably come near the
+truth if we assume the convenient number of 7,920 square statute miles
+as the average measure of the inundated land during the historical
+period. Taking the deposit on this surface at ten feet, the river
+sediment let fall on the soil of Egypt within the last fifty centuries
+would amount to fifteen cubic miles.
+
+Had the Nile been banked in, like the Po, all this deposit, except that
+contained in the water diverted by canals or otherwise drawn from the
+river for irrigation and other purposes, would have been carried out to
+sea.[374] This would have been a considerable quantity; for the Nile
+holds earth in suspension even at low water, a much larger proportion
+during the flood, and irrigation must have been carried on during the
+whole year. The precise amount which would have been thus distributed
+over the soil is matter of conjecture, but three cubic miles is
+certainly a liberal estimate. This would leave twelve cubic miles as the
+quantity which embankments would have compelled the Nile to transport to
+the Mediterranean over and above what it has actually deposited in that
+sea. The Mediterranean is shoal for some miles out to sea along the
+whole coast of the Delta, and the large bays or lagoons within the coast
+line, which communicate both with the river and the sea, have little
+depth of water. These lagoons the river deposits would have filled up,
+and there would still have been surplus earth enough to extend the Delta
+far into the Mediterranean.[375]
+
+
+_Deposits of the Tuscan Rivers._
+
+The Arno, and all the rivers rising on the western slopes and spurs of
+the Apennines, carry down immense quantities of mud to the
+Mediterranean. There can be no doubt that the volume of earth so
+transported is very much greater than it would have been had the soil
+about the headwaters of those rivers continued to be protected from wash
+by forests; and there is as little question that the quantity borne out
+to sea by the rivers of Western Italy is much increased by artificial
+embankments, because they are thereby prevented from spreading over the
+surface the sedimentary matter with which they are charged. The western
+coast of Tuscany has advanced some miles seaward within a very few
+centuries. The bed of the sea, for a long distance, has been raised, and
+of course the relative elevation of the land above it lessened; harbors
+have been filled up and destroyed; long lines of coast dunes have been
+formed, and the diminished inclination of the beds of the rivers near
+their outlets has caused their waters to overflow their banks and
+convert them into pestilential marshes. The territorial extent of
+Western Italy has thus been considerably increased, but the amount of
+soil habitable and cultivable by man has been, in a still higher
+proportion, diminished. The coast of ancient Etruria was filled with
+great commercial towns, and their rural environs were occupied by a
+large and prosperous population. But maritime Tuscany has long been one
+of the most unhealthy districts in Christendom; the famous mart of
+Populonia has not an inhabitant; the coast is almost absolutely
+depopulated, and the malarious fevers have extended their ravages far
+into the interior.
+
+These results are certainly not to be ascribed wholly to human action.
+They are, in a large proportion, due to geological causes over which man
+has no control. The soil of much of Tuscany becomes pasty, almost fluid
+even, as soon as it is moistened, and when thoroughly saturated with
+water, it flows like a river. Such a soil as this would not be
+completely protected by woods, and, indeed, it would now be difficult to
+confine it long enough to allow it to cover itself with forest
+vegetation. Nevertheless, it certainly was once chiefly wooded, and the
+rivers which flow through it must then have been much less charged with
+earthy matter than at present, and they must have carried into the sea a
+smaller proportion of their sediment when they were free to deposit it
+on their banks than since they have been confined by dikes.[376]
+
+It is, in general, true, that the intervention of man has hitherto
+seemed to insure the final exhaustion, ruin, and desolation of every
+province of nature which he has reduced to his dominion. Attila was only
+giving an energetic and picturesque expression to the tendencies of
+human action, as personified in himself, when he said that "no grass
+grew where his horse's hoofs had trod." The instances are few, where a
+second civilization has flourished upon the ruins of an ancient culture,
+and lands once rendered uninhabitable by human acts or neglect have
+generally been forever abandoned as hopelessly irreclaimable. It is, as
+I have before remarked, a question of vast importance, how far it is
+practicable to restore the garden we have wasted, and it is a problem on
+which experience throws little light, because few deliberate attempts
+have yet been made at the work of physical regeneration, on a scale
+large enough to warrant general conclusions in any one class of cases.
+
+The valleys and shores of Tuscany form, however, a striking exception to
+this remark. The success with which human guidance has made the
+operations of nature herself available for the restoration of her
+disturbed harmonies, in the Val di Chiana and the Tuscan Maremma, is
+among the noblest, if not the most brilliant achievements of modern
+engineering, and, regarded in all its bearings on the great question of
+which I have just spoken, it is, as an example, of more importance to
+the general interests of humanity than the proudest work of internal
+improvement that mechanical means have yet constructed. The operations
+in the Val di Chiana have consisted chiefly in so regulating the flow of
+the surface waters into and through it, as to compel them to deposit
+their sedimentary matter at the will of the engineers, and thereby to
+raise grounds rendered insalubrious and unfit for agricultural use by
+stagnating water; the improvements in the Maremma have embraced both
+this method of elevating the level of the soil, and the prevention of
+the mixture of salt water with fresh in the coast marshes and shallow
+bays, which is a very active cause of the development of malarious
+influences.[377]
+
+
+_Improvements in the Val di Chiana._
+
+For twenty miles or more after the remotest headwaters of the Arno have
+united to form a considerable stream, this river flows southeastward to
+the vicinity of Arezzo. It here sweeps round to the northwest, and
+follows that course to near its junction with the Sieve, a few miles
+above Florence, from which point its general direction is westward to
+the sea. From the bend at Arezzo, a depression called the Val di Chiana
+runs southeastward until it strikes into the valley of the Paglia, a
+tributary of the Tiber, and thus connects the basin of the latter river
+with that of the Arno. In the Middle Ages, and down to the eighteenth
+century, the Val di Chiana was often overflowed and devastated by the
+torrents which poured down from the highlands, transporting great
+quantities of slime with their currents, stagnating upon its surface,
+and gradually converting it into a marshy and unhealthy district, which
+was at last very greatly reduced in population and productiveness. It
+had, in fact, become so desolate that even the swallow had deserted
+it.[378]
+
+The bed of the Arno near Arezzo and that of the Paglia at the southern
+extremity of the Val di Chiana did not differ much in level. The
+general inclination of the valley was therefore small; it does not
+appear to have ever been divided into opposite slopes by a true
+watershed, and the position of the summit seems to have shifted
+according to the varying amount and place of deposit of the sediment
+brought down by the lateral streams which emptied into it. The length of
+its principal channel of drainage, and even the direction of its flow at
+any given point, were therefore fluctuating. Hence, much difference of
+opinion was entertained at different times with regard to the normal
+course of this stream, and, consequently, to the question whether it was
+to be regarded as properly an affluent of the Tiber or of the Arno.
+
+The bed of the latter river at the bend has been eroded to the depth of
+thirty or forty feet, and that, apparently, at no very remote period. If
+it were elevated to what was evidently its original height, the current
+of the Arno would be so much above that of the Paglia as to allow of a
+regular flow from its channel to the latter stream, through the Val di
+Chiana, provided the bed of the valley had remained at the level which
+excavations prove it to have had a few centuries ago, before it was
+raised by the deposits I have mentioned. These facts, together with the
+testimony of ancient geographers which scarcely admits of any other
+explanation, are thought to prove that all the waters of the Upper Arno
+were originally discharged through the Val di Chiana into the Tiber, and
+that a part of them still continued to flow, at least occasionally, in
+that direction down to the days of the Roman empire, and perhaps for
+some time later. The depression of the bed of the Arno, and the raising
+of that of the valley by the deposits of the lateral torrents and of the
+Arno itself, finally cut off the branch of the river which had flowed to
+the Tiber, and all its waters were turned into its present channel,
+though the principal drainage of the Val di Chiana appears to have been
+in a southeastwardly direction until within a comparatively recent
+period.
+
+In the sixteenth century, the elevation of the bed of the valley had
+become so considerable, that in 1551, at a point about ten miles south
+of the Arno, it was found to be not less than one hundred and thirty
+feet above that river; then followed a level of ten miles, and then a
+continuous descent to the Paglia. Along the level portion of the valley
+was a boatable channel, and lakes, sometimes a mile or even two miles in
+breadth, had formed at various points farther south. At this period, the
+drainage of the summit level might easily have been determined in either
+direction, and the opposite descents of the valley made to culminate at
+the north or at the south end of the level. In the former case, the
+watershed would have been ten miles south of the Arno; in the latter,
+twenty miles, and the division would have been not very unequal.
+
+Various schemes were suggested at this time for drawing off the stagnant
+waters, as well as for the future regular drainage of the valley, and
+small operations for those purposes were undertaken with partial
+success; but it was feared that the discharge of the accumulated waters
+into the Tiber would produce a dangerous inundation, while the diversion
+of the drainage into the Arno would increase the violence of the floods
+to which that river was very subject, and no decisive steps were taken.
+In 1606, an engineer whose name has not been preserved proposed, as the
+only possible method of improvement, the piercing of a tunnel through
+the hills bounding the valley on the west to convey its waters to the
+Ombrone, but the expense and other objections prevented the adoption of
+this project.[379] The fears of the Roman Government for the security of
+the valley of the Tiber had induced it to construct barriers across that
+part of the channel which lay within its territory, and these
+obstructions, though not specifically intended for that purpose,
+naturally promoted the deposit of sediment and the elevation of the bed
+of the valley in their neighborhood. The effect of this measure and of
+the continued spontaneous action of the torrents was, that the northern
+slope, which in 1551 had commenced at the distance of ten miles from the
+Arno, was found in 1605 to begin, nearly thirty miles south of that
+river, and in 1645 it had been removed about six miles farther in the
+same direction.[380]
+
+In the seventeenth century, the Tuscan and Papal Governments consulted
+Galileo, Torricelli, Castelli, Cassini, Viviani, and other distinguished
+philosophers and engineers, on the possibility of reclaiming the valley
+by a regular artificial drainage. Most of these eminent physicists were
+of opinion that the measure was impracticable, though not altogether for
+the same reasons; but they seem to have agreed in thinking that the
+opening of such channels, in either direction, as would give the current
+a flow sufficiently rapid to drain the lands properly, would dangerously
+augment the inundations of the river--whether the Tiber or the
+Arno--into which the waters should be turned. The general improvement of
+the valley was now for a long time abandoned, and the waters were
+allowed to spread and stagnate until carried off by partial drainage,
+infiltration, and evaporation. Torricelli had contended that the slope
+of a large part of the valley was too small to allow it to be drained by
+ordinary methods, and that no practicable depth and width of canal would
+suffice for that purpose. It could be laid dry, he thought, only by
+converting its surface into an inclined plane, and he suggested that
+this might be accomplished by controlling the flow of the numerous
+torrents which pour into it, so as to force them to deposit their
+sediment at the pleasure of the engineer, and, consequently, to elevate
+the level of the area over which it should be spread.[381] This plan
+did not meet with immediate general acceptance, but it was soon adopted
+for local purposes at some points in the southern part of the valley,
+and it gradually grew in public favor and was extended in application
+until its final triumph a hundred years later.
+
+In spite of these encouraging successes, however, the fear of danger to
+the valley of the Arno and the Tiber, and the difficulty of an agreement
+between Tuscany and Rome--the boundary between which states crossed the
+Val di Chiana not far from the halfway point between the two rivers--and
+of reconciling other conflicting interests, prevented the resumption of
+the projects for the general drainage of the valley until after the
+middle of the eighteenth century. In the mean time the science of
+hydraulics had become better understood, and the establishment of the
+natural law according to which the velocity of a current of water, and
+of course the proportional quantity discharged by it in a given time,
+are increased by increasing its mass, had diminished if not dissipated
+the fear of exposing the banks of the Arno to greater danger from
+inundations by draining the Val di Chiana into it.
+
+The suggestion of Torricelli was finally adopted as the basis of a
+comprehensive system of improvement, and it was decided to continue and
+extend the inversion of the original flow of the waters, and to turn
+them into the Arno from a point as far to the south as should be found
+practicable. The conduct of the works was committed to a succession of
+able engineers who, for a long series of years, were under the general
+direction of the celebrated philosopher and statesman Fossombroni, and
+the success has fully justified the expectations of the most sanguine
+advocates of the scheme. The plan of improvement embraced two branches:
+the one, the removal of certain obstructions in the bed of the Arno,
+and, consequently, the further depression of the channel of that river,
+in certain places, with the view of increasing the rapidity of its
+current; the other, the gradual filling up of the ponds and swamps, and
+raising of the lower grounds of the Val di Chiana, by directing to
+convenient points the flow of the streams which pour down into it, and
+there confining their waters by temporary dams until the sediment was
+deposited where it was needed. The economical result of these operations
+has been, that in 1835 an area of more than four hundred and fifty
+square miles of pond, marsh, and damp, sickly low grounds had been
+converted into fertile, healthy and well-drained soil, and,
+consequently, that so much territory has been added to the agricultural
+domain of Tuscany.
+
+But in our present view of the subject, the geographical revolution
+which has been accomplished is still more interesting. The climatic
+influence of the elevation and draining of the soil must have been
+considerable, though I do not know that an increase or a diminution of
+the mean temperature or precipitation in the valley has been established
+by meteorological observation. There is, however, in the improvement of
+the sanitary condition of the Val di Chiana, which was formerly
+extremely unhealthy, satisfactory proof of a beneficial climatic change.
+The fevers, which not only decimated the population of the low grounds
+but infested the adjacent hills, have ceased their ravages, and are now
+not more frequent than in other parts of Tuscany. The strictly
+topographical effect of the operations in question, besides the
+conversion of marsh into dry surface, has been the inversion of the
+inclination of the valley for a distance of thirty-five miles, so that
+this great plain which, within a comparatively short period, sloped and
+drained its waters to the south, now inclines and sends its drainage to
+the north. The reversal of the currents of the valley has added to the
+Arno a new tributary equal to the largest of its former affluents, and a
+most important circumstance connected with this latter fact is, that the
+increase of the volume of its waters has accelerated their velocity in a
+still greater proportion, and, instead of augmenting the danger from its
+inundations, has almost wholly obviated that source of apprehension.
+Between the beginning of the fifteenth century and the year 1761,
+thirty-one destructive floods of the Arno are recorded; between 1761,
+when the principal streams of the Val di Chiana were diverted into that
+river, and 1835, not one.[382]
+
+
+_Improvements in the Tuscan Maremme._
+
+In the improvements of the Tuscan Maremma, more formidable difficulties
+have been encountered. The territory to be reclaimed was more extensive;
+the salubrious places of retreat for laborers and inspectors were more
+remote; the courses of the rivers to be controlled were longer and their
+natural inclination less rapid; some of them, rising in wooded regions,
+transported comparatively little earthy matter,[383] and above all,
+
+A like example is observed in the Anapus near Syracuse, which, below the
+junction of its two branches, is narrower, though swifter than either of
+them, and such cases are by no means unfrequent. The immediate effect of
+the confluence of two rivers upon the current below depends upon local
+circumstances, and especially upon the angle of incidence. If the two
+nearly coincide in direction, so as to include a small angle, the joint
+current will have a greater velocity than the slower confluent, perhaps
+even than either of them. If the two rivers run in transverse, still
+more if they flow in more or less opposite directions, the velocity of
+the principal branch will be retarded both above and below the junction,
+and at high water it may even set back the current of the affluent.
+
+On the other hand, the diversion of a considerable branch from a river
+retards its velocity below the point of separation, and here a deposit
+of earth in its channel immediately begins, which has a tendency to turn
+the whole stream into the new bed. "Theory and the authority of all
+hydrographical writers combine to show that the channels of rivers
+undergo an elevation of bed below a canal of diversion."--Letter of
+FOSSOMBRONI, in SALVAGNOLI, _Raccolta di Documenti_, p. 32. See the
+early authorities and discussions on the principle stated in the text,
+in FRISI, _Del modo di regolare i Fiumi e i Torrenti_, libro iii, capit.
+i. the coast, which is a recent deposit of the waters, is little
+elevated above the sea, and admits into its lagoons and the mouths of
+its rivers floods of salt water with every western wind, every rising
+tide.[384]
+
+The western coast of Tuscany is not supposed to have been an unhealthy
+region before the conquest of Etruria by the Romans, but it certainly
+became so within a few centuries after that event. This was a natural
+consequence of the neglect or wanton destruction of the public
+improvements, and especially the hydraulic works in which the Etruscans
+were so skilful, and of the felling of the upland forests, to satisfy
+the demand for wood at Rome for domestic, industrial, and military
+purposes. After the downfall of the Roman empire, the incursions of the
+barbarians, and then feudalism, foreign domination, intestine wars, and
+temporal and spiritual tyrannies, aggravated still more cruelly the
+moral and physical evils which Tuscany and the other Italian States were
+doomed to suffer, and from which they have enjoyed but brief respites
+during the whole period of modern history. The Maremma was already
+proverbially unhealthy in the time of Dante, who refers to the fact in
+several familiar passages, and the petty tyrants upon its borders often
+sent criminals to places of confinement in its territory, as a slow but
+certain mode of execution. Ignorance of the causes of the insalubrity,
+and often the interference of private rights,[385] prevented the
+adoption of measures to remove it, and the growing political and
+commercial importance of the large towns in more healthful localities
+absorbed the attention of Government, and deprived the Maremma of its
+just share in the systems of physical improvement which were
+successfully adopted in interior and Northern Italy.
+
+Before any serious attempts were made to drain or fill up the marshes of
+the Maremme, various other sanitary experiments were tried. It was
+generally believed that the insalubrity of the province was the
+consequence, not the cause, of its depopulation, and that, if it were
+once densely inhabited, the ordinary operations of agriculture, and
+especially the maintenance of numerous domestic fires, would restore it
+to its ancient healthfulness.[386] In accordance with these views,
+settlers were invited from various parts of Italy, from Greece, and,
+after the accession of the Lorraine princes, from that country also, and
+colonized in the Maremme. To strangers coming from soils and skies so
+unlike those of the Tuscan marshes, the climate was more fatal than to
+the inhabitants of the neighboring districts, whose constitutions had
+become in some degree inured to the local influences, or who at least
+knew better how to guard against them. The consequence very naturally
+was that the experiment totally failed to produce the desired effects,
+and was attended with a great sacrifice of life and a heavy loss to the
+treasury of the state.
+
+The territory known as the Tuscan Maremma, _ora maritima_, or
+Maremme--for the plural form is most generally used--lies upon and near
+the western coast of Tuscany, and comprises about 1,900 square miles
+English, of which 500 square miles, or 320,000 acres, are plain and
+marsh including 45,500 acres of water surface, and about 290,000 acres
+are forest. One of the mountain peaks, that of Mount Amiata, rises to
+the height of 6,280 feet. The mountains of the Maremma are healthy, the
+lower hills much less so, as the malaria is felt at some points at the
+height of 1,000 feet, and the plains, with the exception of a few
+localities favorably situated on the seacoast, are in a high degree
+pestilential. The fixed population is about 80,000, of whom one sixth
+live on the plains in the winter and about one tenth in the summer. Nine
+or ten thousand laborers come down from the mountains of the Maremma and
+the neighboring provinces into the plain, during the latter season, to
+cultivate and gather the crops.
+
+Out of this small number of inhabitants and strangers, 35,619 were ill
+enough to require medical treatment between the 1st of June, 1840, and
+the 1st of June, 1841, and more than one half the cases were of
+intermittent, malignant, gastric, or catarrhal fever. Very few
+agricultural laborers escaped fever, though the disease did not always
+manifest itself until they had returned to the mountains. In the
+province of Grosseto, which embraces nearly the whole of the Maremma,
+the annual mortality was 3.92 per cent. the average duration of life but
+23.18 years, and 75 per cent. of the deaths were among persons engaged
+in agriculture.
+
+The filling up of the low grounds and the partial separation of the
+waters of the sea and the land, which had been in progress since the
+year 1827, now began to show very decided effects upon the sanitary
+condition of the population. In the year ending June 1st, 1842, the
+number of the sick was reduced by more than 2,000, and the cases of
+fever by more than 4,000. The next year, the cases of fever fell to
+10,500, and in that ending June 1st, 1844, to 9,200. The political
+events of 1848 and the preceding and following years, occasioned the
+suspension of the works of improvement in the Maremma, but they were
+resumed after the revolution of 1859, and are now in successful
+progress.
+
+I have spoken, with some detail, of the improvements in the Val di
+Chiana and the Tuscan Maremma, because of their great relative
+importance, and because their history is well known; but like operations
+have been executed in the territory of Pisa and upon the coast of the
+duchy of Lucca. In the latter case, they were confined principally to
+prevention of the intermixing of fresh water with that of the sea. In
+1741, sluices or lock gates were constructed for this purpose, and the
+following year, the fevers, which had been destructive to the coast
+population for a long time previous, disappeared altogether. In 1768 and
+1769, the works having fallen to decay, the fevers returned in a very
+malignant form, but the rebuilding of the gates again restored the
+healthfulness of the shore. Similar facts recurred in 1784 and 1785, and
+again from 1804 to 1821. This long and repeated experience has at last
+impressed upon the people the necessity of vigilant attention to the
+sluices, which are now kept in constant repair. The health of the coast
+is uninterrupted, and Viareggio, the capital town of the district, is
+now much frequented for its sea baths and its general salubrity, at a
+season when formerly it was justly shunned as the abode of disease and
+death.[387]
+
+It is now a hundred years since the commencement of the improvements in
+the Val di Chiana, and those of the Maremma have been in more or less
+continued operation for above a generation. They have, as we have seen,
+produced important geographical changes in the surface of the earth and
+in the flow of considerable rivers, and their effects have been not less
+conspicuous in preventing other changes, of a deleterious character,
+which would infallibly have taken place if they had not been arrested by
+the improvements in question. It has been already stated that, in order
+to prevent the overflow of the valley of the Tiber by freely draining
+the Val di Chiana into it, the Papal authorities, long before the
+commencement of the Tuscan works, constructed strong barriers near the
+southern end of the valley, which detained the waters of the wet season
+until they could be gradually drawn off into the Paglia. They
+consequently deposited most of their sediment in the Val di Chiana and
+carried down comparatively little earth to the Tiber. The lateral
+streams contributing the largest quantities of sedimentary matter to the
+Val di Chiana originally flowed into that valley near its northern end;
+and the change of their channels and outlets in a southern direction, so
+as to raise that part of the valley by their deposits and thereby
+reverse its drainage, was one of the principal steps in the process of
+improvement.
+
+We have seen that the north end of the Val di Chiana near the Arno had
+been raised by spontaneous deposit of sediment to such a height as to
+interpose a sufficient obstacle to all flow in that direction. If, then,
+the Roman dam had not been erected, or the works of the Tuscan
+Government undertaken, the whole of the earth, which has been arrested
+by those works and employed to raise the bed and reverse the declivity
+of the valley, would have been carried down to the Tiber and thence into
+the sea. The deposit thus created, would, of course, have contributed to
+increase the advance of the shore at the mouth of that river, which has
+long been going on at the rate of three metres and nine tenths (twelve
+feet and nine inches) per annum.[388] It is evident that a quantity of
+earth, sufficient to effect the immense changes I have described in a
+wide valley more than thirty miles long, if deposited at the outlet of
+the Tiber, would have very considerably modified the outline of the
+coast, and have exerted no unimportant influence on the flow of that
+river, by raising its point of discharge and lengthening its channel.
+
+The sediment washed into the marshes of the Maremme is not less than
+12,000,000 cubic yards per annum. The escape of this quantity into the
+sea, which is now almost wholly prevented, would be sufficient to
+advance the coast line fourteen yards per year, for a distance of forty
+miles, computing the mean depth of the sea near the shore at twelve
+yards. It is true that in this case, as well as in that of other rivers,
+the sedimentary matter would not be distributed equally along the shore,
+and much of it would be carried out into deep water, or perhaps
+transported by the currents to distant coasts. The immediate effects of
+the deposit, therefore, would not be so palpable as they appear in this
+numerical form, but they would be equally certain, and would infallibly
+manifest themselves, first, perhaps, at some remote point, and afterward
+at or near the outlets of the rivers which produced them.
+
+
+_Obstruction of River Mouths._
+
+The mouths of a large proportion of the streams known to ancient
+internal navigation are already blocked up by sandbars or fluviatile
+deposits, and the maritime approaches to river harbors frequented by the
+ships of Phenicia and Carthage and Greece and Rome are shoaled to a
+considerable distance out to sea. The inclination of almost every known
+river bed has been considerably reduced within the historical period,
+and nothing but great volume of water, or exceptional rapidity of flow,
+now enables a few large streams like the Amazon, the La Plata, the
+Ganges, and, in a less degree, the Mississippi, to carry their own
+deposits far enough out into deep water to prevent the formation of
+serious obstructions to navigation. But the degradation of their banks,
+and the transportation of earthy matter to the sea by their currents,
+are gradually filling up the estuaries even of these mighty floods, and
+unless the threatened evil shall be averted by the action of geological
+forces, or by artificial contrivances more efficient than dredging
+machines, the destruction of every harbor in the world which receives a
+considerable river must inevitably take place at no very distant date.
+
+This result would, perhaps, have followed in some incalculably distant
+future, if man had not come to inhabit the earth as soon as the natural
+forces which had formed its surface had arrived at such an approximate
+equilibrium that his existence on the globe was possible; but the
+general effect of his industrial operations has been to accelerate it
+immensely. Rivers, in countries planted by nature with forests and never
+inhabited by man, employ the little earth and gravel they transport
+chiefly to raise their own beds and to form plains in their basins.[389]
+In their upper course, where the current is swiftest, they are most
+heavily charged with coarse rolled or suspended matter, and this, in
+floods, they deposit on their shores in the mountain valleys where they
+rise; in their middle course, a lighter earth is spread over the bottom
+of their widening basins, and forms plains of moderate extent; the fine
+silt which floats farther is deposited over a still broader area, or, if
+carried out to sea, is, in great part quickly swept far off by marine
+currents and dropped at last in deep water. Man's "improvement" of the
+soil increases the erosion from its surface; his arrangements for
+confining the lateral spread of the water in floods compel the rivers to
+transport to their mouths the earth derived from that erosion even in
+their upper course; and, consequently, the sediment they deposit at
+their outlets is not only much larger in quantity, but composed of
+heavier materials, which sink more readily to the bottom of the sea and
+are less easily removed by marine currents.
+
+The tidal movement of the ocean, deep sea currents, and the agitation of
+inland waters by the wind, lift up the sands strewn over the bottom by
+diluvial streams or sent down by mountain torrents, and throw them up on
+dry land, or deposit them in sheltered bays and nooks of the coast--for
+the flowing is stronger than the ebbing tide, the affluent than the
+refluent wave. This cause of injury to harbors it is not in man's power
+to resist by any means at present available; but, as we have seen,
+something can be done to prevent the degradation of high grounds, and to
+diminish the quantity of earth which is annually abstracted from the
+mountains, from table lands, and from river banks, to raise the bottom
+of the sea.
+
+This latter cause of harbor obstruction, though an active agent, is,
+nevertheless, in many cases, the less powerful of the two. The earth
+suspended in the lower course of fluviatile currents is lighter than sea
+sand, river water lighter than sea water, and hence, if a land stream
+enters the sea with a considerable volume, its water flows over that of
+the sea, and bears its slime with it until it lets it fall far from
+shore, or, as is more frequently the case, mingles with some marine
+current and transports its sediment to a remote point of deposit. The
+earth borne out of the mouths of the Nile is in part carried over the
+waves which throw up sea sand on the beach, and deposited in deep water,
+in part drifted by the current, which sweeps east and north along the
+coasts of Egypt and Syria, until it finds a resting place in the
+northeastern angle of the Mediterranean.[390] Thus the earth loosened by
+the rude Abyssinian ploughshare, and washed down by the rain from the
+hills of Ethiopia which man has stripped of their protecting forests,
+contributes to raise the plains of Egypt, to shoal the maritime channels
+which lead to the city built by Alexander near the mouth of the Nile,
+and to fill up the harbors made famous by Phenician commerce.
+
+
+_Subterranean Waters._
+
+I have frequently alluded to a branch of geography, the importance of
+which is but recently adequately recognized--the subterranean waters of
+the earth considered as stationary reservoirs, as flowing currents, and
+as filtrating fluids. The earth drinks in moisture by direct absorption
+from the atmosphere, by the deposition of dew, by rain and snow, by
+percolation from rivers and other superficial bodies of water, and
+sometimes by currents flowing into caves or smaller visible
+apertures.[391] Some of this humidity is exhaled again by the soil,
+some is taken up by organic growths and by inorganic compounds, some
+poured out upon the surface by springs and either immediately evaporated
+or carried down to larger streams and to the sea, some flows by
+subterranean courses into the bed of fresh-water rivers[392] or of the
+ocean, and some remains, though even here not in forever motionless
+repose, to fill deep cavities and underground channels.[393] In every
+case the aqueous vapors of the air are the ultimate source of supply,
+and all these hidden stores are again returned to the atmosphere by
+evaporation.
+
+The proportion of the water of precipitation taken up by direct
+evaporation from the surface of the ground seems to have been generally
+exaggerated, sufficient allowance not being made for moisture carried
+downward, or in a lateral direction, by infiltration or by crevices in
+the superior rocky or earthy strata. According to Wittwer, Mariotte
+found that but one sixth of the precipitation in the basin of the Seine
+was delivered into the sea by that river, "so that five sixths remained
+for evaporation and consumption by the organic world."[394]
+
+Lieutenant Maury--whose scientific reputation, though fallen, has not
+quite sunk to the level of his patriotism--estimates the annual amount
+of precipitation in the valley of the Mississippi at 620 cubic miles,
+the discharge of that river into the sea at 107 cubic miles, and
+concludes that "this would leave 513 cubic miles of water to be
+evaporated from this river basin annually."[395] In these and other like
+computations, the water carried down into the earth by capillary and
+larger conduits is wholly lost sight of, and no thought is bestowed upon
+the supply for springs, for common and artesian wells, and for
+underground rivers, like those in the great caves of Kentucky, which may
+gush up in fresh-water currents at the bottom of the Caribbean Sea, or
+rise to the light of day in the far-off peninsula of Florida.
+
+The progress of the emphatically modern science of geology has corrected
+these erroneous views, because the observations on which it depends have
+demonstrated not only the existence, but the movement, of water in
+nearly all geological formations, have collected evidence of the
+presence of large reservoirs at greater or less depths beneath surfaces
+of almost every character, and have investigated the rationale of the
+attendant phenomena. The distribution of these waters has been minutely
+studied with reference to a great number of localities, and though the
+actual mode of their vertical and horizontal transmission is still
+involved in much doubt, the laws which determine their aggregation are
+so well understood, that, when the geology of a given district is known,
+it is not difficult to determine at what depth water will be reached by
+the borer, and to what height it will rise.
+
+The same principles have been successfully applied to the discovery of
+small subterranean collections or currents of water, and some persons
+have acquired, by a moderate knowledge of the superficial structure of
+the earth combined with long practice, a skill in the selection of
+favorable places for digging wells which seems to common observers
+little less than miraculous. The Abbe Paramelle--a French ecclesiastic
+who devoted himself for some years to this subject and was extensively
+employed as a well-finder--states, in his work on Fountains, that in the
+course of thirty-four years he had pointed out more than ten thousand
+subterranean springs, and though his geological speculations were often
+erroneous, the highest scientific authorities in Europe have testified
+to the great practical value of his methods, and the almost infallible
+certainty of his predictions.[396]
+
+Babinet quotes a French proverb, "Summer rain wets nothing," and
+explains it as meaning that the water of such rains is "almost totally
+taken up by evaporation." "The rains of summer," he adds, "however
+abundant they may be, do not penetrate the soil to a greater depth than
+15 or 20 centimetres. In summer the evaporating power of the heat is
+five or six times as great as in winter, and this power is exerted by an
+atmosphere capable of containing five times as much vapor as in winter."
+"A stratum of snow which prevents evaporation [from the soil] causes
+almost all the water that composes it to filter down into the earth, and
+form a reserve for springs, wells, and rivers which could not be
+supplied by any amount of summer rain." "This latter--useful, indeed
+like dew, to vegetation--does not penetrate the soil and accumulate a
+store to feed springs and to be brought up by them to the open
+air."[397] This conclusion, however applicable it may be to the climate
+and soil of France, is too broadly stated to be accepted as a general
+truth, and in countries where the precipitation is small in the winter
+months, familiar observation shows that the quantity of water yielded by
+deep wells and natural springs depends not less on the rains of summer
+than on those of the rest of the year, and, consequently, that much of
+the precipitation of that season must find its way to strata too deep to
+lose water by evaporation.
+
+The supply of subterranean reservoirs and currents, as well as of
+springs, is undoubtedly derived chiefly from infiltration, and hence it
+must be affected by all changes of the natural surface that accelerate
+or retard the drainage of the soil, or that either promote or obstruct
+evaporation from it. It has sufficiently appeared from what has gone
+before, that the spontaneous drainage of cleared ground is more rapid
+than that of the forest, and consequently, that the felling of the
+woods, as well as the draining of swamps, deprives the subterranean
+waters of accessions which would otherwise be conveyed to them by
+infiltration. The same effect is produced by artificial contrivances for
+drying the soil either by open ditches or by underground pipes or
+channels, and in proportion as the sphere of these operations is
+extended, the effect of them cannot fail to make itself more and more
+sensibly felt in the diminished supply of water furnished by wells and
+running springs.[398]
+
+It is undoubtedly true that loose soils, stripped of vegetation and
+broken up by the plough or other processes of cultivation, may, until
+again carpeted by grasses or other plants, absorb more rain and snow
+water than when they were covered by a natural growth; but it is also
+true that the evaporation from such soils is augmented in a still
+greater proportion. Rain scarcely penetrates beneath the sod of grass
+ground, but runs off over the surface; and after the heaviest showers a
+ploughed field will often be dried by evaporation before the water can
+be carried off by infiltration, while the soil of a neighboring grove
+will remain half saturated for weeks together. Sandy soils frequently
+rest on a tenacious subsoil, at a moderate depth, as is usually seen in
+the pine plains of the United States, where pools of rain water collect
+in slight depressions on the surface of earth, the upper stratum of
+which is as porous as a sponge. In the open grounds such pools are very
+soon dried up by the sun and wind; in the woods they remain unevaporated
+long enough for the water to diffuse itself laterally until it finds, in
+the subsoil, crevices through which it may escape, or slopes which it
+may follow to their outcrop or descend along them to lower strata.
+
+The readiness with which water not obstructed by impermeable strata
+diffuses itself through the earth in all directions--and, consequently,
+the importance of keeping up the supply of subterranean reservoirs--find
+a familiar illustration in the effect of paving the ground about the
+stems of vines and trees. The surface earth around the trunk of a tree
+may be made perfectly impervious to water, by flag stones and cement,
+for a distance greater than the spread of the roots; and yet the tree
+will not suffer for want of moisture, except in droughts severe enough
+sensibly to affect the supply in deep wells and springs. Both forest and
+fruit trees grow well in cities where the streets and courts are closely
+paved, and where even the lateral access of water to the roots is more
+or less obstructed by deep cellars and foundation walls. The deep-lying
+veins and sheets of water, supplied by infiltration from above, send up
+moisture by capillary attraction, and the pavement prevents the soil
+beneath it from losing its humidity by evaporation. Hence, city-grown
+trees find moisture enough for their roots, and though plagued with
+smoke and dust, often retain their freshness while those planted in the
+open fields, where sun and wind dry up the soil faster than the
+subterranean fountains can water it, are withering from drought. Without
+the help of artificial conduit or of water carrier, the Thames and the
+Seine refresh the ornamental trees that shade the thoroughfares of
+London and of Paris, and beneath the hot and reeking mould of Egypt, the
+Nile sends currents to the extremest border of its valley.[399]
+
+
+_Artesian Wells._
+
+The existence of artesian wells depends upon that of subterranean
+reservoirs and rivers, and the supply yielded by borings is regulated by
+the abundance of such sources. The waters of the earth are, in many
+cases, derived from superficial currents which are seen to pour into
+chasms opened, as it were, expressly for their reception; and in others
+where no apertures in the crust of the earth have been detected, their
+existence is proved by the fact that artesian wells sometimes bring up
+from great depths seeds, leaves, and even living fish, which must have
+been carried down through channels large enough to admit a considerable
+stream. But in general, the sheets and currents of water reached by deep
+boring appear to be primarily due to infiltration from highlands where
+the water is first collected in superficial or subterranean reservoirs.
+By means of channels conforming to the dip of the strata, these
+reservoirs communicate with the lower basins, and exert upon them a
+fluid pressure sufficient to raise a column to the surface, whenever an
+orifice is opened.[400] The water delivered by an artesian well is,
+therefore, often derived from distant sources, and may be wholly
+unaffected by geographical or meteorological changes in its immediate
+neighborhood, while the same changes may quite dry up common wells and
+springs which are fed only by the local infiltration of their own narrow
+basins.
+
+In most cases, artesian wells have been bored for purely economical or
+industrial purposes, such as to obtain good water for domestic use or
+for driving light machinery, to reach saline or other mineral springs,
+and recently, in America, to open fountains of petroleum or rock oil.
+The geographical and geological effects of such abstraction of fluids
+from the bowels of the earth are too remote and uncertain to be here
+noticed;[401] but artesian wells have lately been employed in Algeria
+for a purpose which has even now a substantial, and may hereafter
+acquire a very great geographical importance. It was observed by many
+earlier as well as recent travellers in the East, among whom Shaw
+deserves special mention, that the Libyan desert, bordering upon the
+cultivated shores of the Mediterranean, appeared in many places to rest
+upon a subterranean lake at an accessible distance below the surface.
+The Moors are vaguely said to have _bored_ artesian wells down to this
+reservoir, to obtain water for domestic use and irrigation, but I do
+not find such wells described by any trustworthy traveller, and the
+universal astonishment and incredulity with which the native tribes
+viewed the operations of the French engineers sent into the desert for
+that purpose, are a sufficient proof that this mode of reaching the
+subterranean waters was new to them. They were, however, aware of the
+existence of water below the sands, and were dexterous in digging
+wells--square shafts lined with a framework of palm-tree stems--to the
+level of the sheet. The wells so constructed, though not technically
+artesian wells, answer the same purpose; for the water rises to the
+surface and flows over it as from a spring.[402]
+
+These wells, however, are too few and too scanty in supply to serve any
+other purposes than the domestic wells of other countries, and it is but
+recently that the transformation of desert into cultivable land by this
+means has been seriously attempted. The French Government has bored a
+large number of artesian wells in the Algerian desert within a few
+years, and the native sheikhs are beginning to avail themselves of the
+process. Every well becomes the nucleus of a settlement proportioned to
+the supply of water, and before the end of the year 1860, several nomade
+tribes had abandoned their wandering life, established themselves around
+the wells, and planted more than 30,000 palm trees, besides other
+perennial vegetables.[403] The water is found at a small depth,
+generally from 100 to 200 feet, and though containing too large a
+proportion of mineral matter to be acceptable to a European palate, it
+answers well for irrigation, and does not prove unwholesome to the
+natives.
+
+The most obvious use of artesian wells in the desert at present is that
+of creating stations for the establishment of military posts and halting
+places for the desert traveller; but if the supply of water shall prove
+adequate for the indefinite extension of the system, it is probably
+destined to produce a greater geographical transformation than has ever
+been effected by any scheme of human improvement. The most striking
+contrast of landscape scenery that nature brings near together in time
+or place, is that between the greenery of the tropics, or of a northern
+summer, and the snowy pall of leafless winter. Next to this in startling
+novelty of effect, we must rank the sudden transition from the shady and
+verdant oasis of the desert to the bare and burning party-colored ocean
+of sand and rock which surrounds it.[404] The most sanguine believer in
+indefinite human progress hardly expects that man's cunning will
+accomplish the universal fufilment of the prophecy, "the desert shall
+blossom as the rose," in its literal sense; but sober geographers have
+thought the future conversion of the sand plains of Northern Africa into
+fruitful gardens, by means of artesian wells, not an improbable
+expectation. They have gone farther, and argued that, if the soil were
+covered with fields and forests, vegetation would call down moisture
+from the Libyan sky, and that the showers which are now wasted on the
+sea, or so often deluge Southern Europe with destructive inundation,
+would in part be condensed over the arid wastes of Africa, and thus,
+without further aid from man, bestow abundance on regions which nature
+seems to have condemned to perpetual desolation.
+
+An equally bold speculation, founded on the well-known fact, that the
+temperature of the earth and of its internal waters increases as we
+descend beneath the surface, has suggested that artesian wells might
+supply heat for industrial and domestic purposes, for hot-house
+cultivation, and even for the local amelioration of climate. The success
+with which Count Lardarello has employed natural hot springs for the
+evaporation of water charged with boracic acid, and other fortunate
+applications of the heat of thermal sources, lend some countenance to
+the latter project; but both must, for the present, be ranked among the
+vague possibilities of science, not regarded as probable future triumphs
+of man over nature.
+
+
+_Artificial Springs._
+
+A more plausible and inviting scheme is that of the creation of
+perennial springs by husbanding rain and snow water, storing it up in
+artificial reservoirs of earth, and filtering it through purifying
+strata, in analogy with the operations of nature. The sagacious
+Palissy--starting from the theory that all springs are primarily derived
+from precipitation, and reasoning justly on the accumulation and
+movement of water in the earth--proposed to reduce theory to practice,
+and to imitate the natural processes by which rain is absorbed by the
+earth and given out again in running fountains. "When I had long and
+diligently considered the cause of the springing of natural fountains
+and the places where they be wont to issue," says he, "I did plainly
+perceive, at last, that they do proceed and are engendered of nought but
+the rains. And it is this, look you, which hath moved me to enterprise
+the gathering together of rain water after the manner of nature, and the
+most closely according to her fashion that I am able; and I am well
+assured that by following the formulary of the Supreme Contriver of
+fountains, I can make springs, the water whereof shall be as good and
+pure and clear as of such which be natural."[405] Palissy discusses the
+subject of the origin of springs at length and with much ability,
+dwelling specially on infiltration, and, among other things, thus
+explains the frequency of springs in mountainous regions: "Having well
+considered the which, thou mayest plainly see the reason why there be
+more springs and rivulets proceeding from the mountains than from the
+rest of the earth; which is for no other cause but that the rocks and
+mountains do retain the water of the rains like vessels of brass. And
+the said waters falling upon the said mountains descend continually
+through the earth, and through crevices, and stop not till they find
+some place that is bottomed with stone or close and thick rocks; and
+they rest upon such bottom until they find some channel or other manner
+of issue, and then they flow out in springs or brooks or rivers,
+according to the greatness of the reservoirs and of the outlets
+thereof."[406]
+
+After a full exposition of his theory, Palissy proceeds to describe his
+method of creating springs, which is substantially the same as that
+lately proposed by Babinet in the following terms: "Choose a piece of
+ground containing four or five acres, with a sandy soil, and with a
+gentle slope to determine the flow of the water. Along its upper line,
+dig a trench five or six feet deep and six feet wide. Level the bottom
+of the trench, and make it impermeable by paving, by macadamizing, by
+bitumen, or, more simply and cheaply, by a layer of clay. By the side of
+this trench dig another, and throw the earth from it into the first, and
+so on until you have rendered the subsoil of the whole parcel
+impermeable to rain water. Build a wall along the lower line with an
+aperture in the middle for the water, and plant fruit or other low trees
+upon the whole, to shade the ground and check the currents of air which
+promote evaporation. This will infallibly give you a good spring which
+will flow without intermission and supply the wants of a whole hamlet or
+a large chateau."[407] Babinet states that the whole amount of
+precipitation on a reservoir of the proposed area, in the climate of
+Paris, would be about 13,000 cubic yards, not above one half of which,
+he thinks, would be lost, and, of course, the other half would remain
+available to supply the spring. I much doubt whether this expectation
+would be realized in practice, in its whole extent; for if Babinet is
+right in supposing that the summer rain is wholly evaporated, the winter
+rains, being much less in quantity, would hardly suffice to keep the
+earth saturated and give off so large a surplus.
+
+The method of Palissy, though, as I have said, similar in principle to
+that of Babinet, would be cheaper of execution, and, at the same time,
+more efficient. He proposes the construction of relatively small
+filtering receptacles, into which he would conduct the rain falling upon
+a large area of rocky hillside, or other sloping ground not readily
+absorbing water. This process would, in all probability, be a very
+successful, as well as an inexpensive, mode of economizing atmospheric
+precipitation, and compelling the rain and snow to form perennial
+fountains at will.
+
+
+_Economizing Precipitation._
+
+The methods suggested by Palissy and by Babinet are of limited
+application, and designed only to supply a sufficient quantity of water
+for the domestic use of small villages or large private establishments.
+Dumas has proposed a much more extensive system for collecting and
+retaining the whole precipitation in considerable valleys, and storing
+it in reservoirs, whence it is to be drawn for household and mechanical
+purposes, for irrigation, and, in short, for all the uses to which the
+water of natural springs and brooks is applicable. His plan consists in
+draining both surface and subsoil, by means of conduits differing in
+construction according to local circumstances, but in the main not
+unlike those employed in improved agriculture, collecting the water in a
+central channel, securing its proper filterage, checking its too rapid
+flow by barriers at convenient points, and finally receiving the whole
+in spacious covered reservoirs, from which it may be discharged in a
+constant flow or at intervals as convenience may dictate.[408]
+
+There is no reasonable doubt that a very wide employment of these
+various contrivances for economizing and supplying water is practicable,
+and the expediency of resorting to them is almost purely an economical
+question. There appears to be no serious reason to apprehend collateral
+evils from them, and in fact all of them, except artesian wells, are
+simply indirect methods of returning to the original arrangements of
+nature, or, in other words, of restoring the fluid circulation of the
+globe; for when the earth was covered with the forest, perennial springs
+gushed from the foot of every hill, brooks flowed down the bed of every
+valley. The partial recovery of the fountains and rivulets which once
+abundantly watered the face of the agricultural world seems practicable
+by such means, even without any general replanting of the forests; and
+the cost of one year's warfare, if judiciously expended in a combination
+of both methods of improvement, would secure, to almost every country
+that man has exhausted, an amelioration of climate, a renovated
+fertility of soil, and a general physical improvement, which might
+almost be characterized as a new creation.
+
+
+
+
+CHAPTER V.
+
+THE SANDS.
+
+ORIGIN OF SAND--SAND NOW CARRIED DOWN TO THE SEA--THE SANDS OF EGYPT AND
+THE ADJACENT DESERT----THE SUEZ CANAL----THE SANDS OF EGYPT--COAST DUNES
+AND SAND PLAINS--SAND BANKS--DUNES ON COAST OF AMERICA--DUNES OF WESTERN
+EUROPE--FORMATION OF DUNES--CHARACTER OF DUNE SAND--INTERIOR STRUCTURE
+OF DUNES--FORM OF DUNES--GEOLOGICAL IMPORTANCE OF DUNES--INLAND DUNES--
+AGE, CHARACTER, AND PERMANENCE OF DUNES--USE OF DUNES AS BARRIER AGAINST
+THE SEA--ENCROACHMENTS OF THE SEA--THE LIIMFJORD--ENCROACHMENTS OF THE
+SEA--DRIFTING OF DUNE SANDS--DUNES OF GASCONY--DUNES OF DENMARK--DUNES
+OF PRUSSIA--ARTIFICIAL FORMATION OF DUNES--TREES SUITABLE FOR DUNE
+PLANTATIONS--EXTENT OF DUNES IN EUROPE--DUNE VINEYARDS OF CAPE BRETON--
+REMOVAL OF DUNES--INLAND SAND PLAINS--THE LANDES OF GASCONY--THE BELGIAN
+CAMPINE--SANDS AND STEPPES OF EASTERN EUROPE--ADVANTAGES OF RECLAIMING
+DUNES--GOVERNMENT WORKS OF IMPROVEMENT.
+
+
+_Origin of Sand._
+
+Sand, which is found in beds or strata at the bottom of the sea or in
+the channels of rivers, as well as in extensive deposits upon or beneath
+the surface of the dry land, appears to consist essentially of the
+detritus of rocks. It is not always by any means clear through what
+agency the solid rock has been reduced to a granular condition; for
+there are beds of quartzose sand, where the sharp, angular shape of the
+particles renders it highly improbable that they have been formed by
+gradual abrasion and attrition, and where the supposition of a crushing
+mechanical force seems equally inadmissible. In common sand, the quartz
+grains are the most numerous; but this is not a proof that the rocks
+from which these particles were derived were wholly, or even chiefly,
+quartzose in character; for, in many composite rocks, as, for example,
+in the granitic group, the mica, felspar, and hornblende are more easily
+decomposed by chemical action, or disintegrated, comminuted, and reduced
+to an impalpable state by mechanical force, than the quartz. In the
+destruction of such rocks, therefore, the quartz would survive the other
+ingredients, and remain unmixed, when they had been decomposed and had
+entered into new chemical combinations, or been ground to slime and
+washed away by water currents.
+
+The greater or less specific gravity of the different constituents of
+rock doubtless aids in separating them into distinct masses when once
+disintegrated, though there are veined and stratified beds of sand where
+the difference between the upper and lower layers, in this respect, is
+too slight to be supposed capable of effecting a complete
+separation.[409] In cases where rock has been reduced to sandy fragments
+by heat, or by obscure chemical and other molecular forces, the sandbeds
+may remain undisturbed, and represent, in the series of geological
+strata, the solid formations from which they were derived. The large
+masses of sand not found in place have been transported and accumulated
+by water or by wind, the former being generally considered the most
+important of these agencies; for the extensive deposits of the Sahara,
+of the deserts of Persia, and of that of Gobi, are commonly supposed to
+have been swept together or distributed by marine currents, and to have
+been elevated above the ocean by the same means as other upheaved
+strata.
+
+Meteoric and mechanical influences are still active in the reduction of
+rocks to a fragmentary state; but the quantity of sand now transported
+to the sea seems to be comparatively inconsiderable, because--not to
+speak of the absence of diluvial action--the number of torrents emptying
+directly into the sea is much less than it was at earlier periods. The
+formation of alluvial plains in maritime bays, by the sedimentary matter
+brought down from the mountains, has lengthened the flow of such streams
+and converted them very generally into rivers, or rather affluents of
+rivers much younger than themselves. The filling up of the estuaries has
+so reduced the slope of all large and many small rivers, and,
+consequently, so checked the current of what the Germans call their
+_Unterlauf_, or lower course, that they are much less able to transport
+heavy material than at earlier epochs. The slime deposited by rivers at
+their junction with the sea, is usually found to be composed of material
+too finely ground and too light to be denominated sand, and it can be
+abundantly shown that the sandbanks at the outlet of large streams are
+of tidal, not of fluviatile origin, or, in lakes and tideless seas, a
+result of the concurrent action of waves and of wind.
+
+Large deposits of sand, therefore, must in general be considered as of
+ancient, not of recent formation, and many eminent geologists ascribe
+them to diluvial action. Staring has discussed this question very fully,
+with special reference to the sands of the North Sea, the Zuiderzee, and
+the bays and channels of the Dutch coast.[410] His general conclusion
+is, that the rivers of the Netherlands "move sand only by a very slow
+displacement of sandbanks, and do not carry it with them as a suspended
+or floating material." The sands of the German Ocean he holds to be a
+product of the "great North German drift," deposited where they now lie
+before the commencement of the present geological period, and he
+maintains similar opinions with regard to the sands thrown up by the
+Mediterranean at the mouths of the Nile and on the Barbary coast.[411]
+
+
+_Sand now carried to the Sea._
+
+There are, however, cases where mountain streams still bear to the sea
+perhaps relatively small, but certainly absolutely large, amounts of
+disintegrated rock.[412] The quantity of sand and gravel carried into
+the Mediterranean by the torrents of the Maritime Alps, the Ligurian
+Apennines, the islands of Corsica, Sardinia, and Sicily, and the
+mountains of Calabria, is apparently great. In mere mass, it is
+possible, if not probable, that as much rocky material, more or less
+comminuted, is contributed to the basin of the Mediterranean by Europe,
+even excluding the shores of the Adriatic and the Euxine, as is washed
+up from it upon the coasts of Africa and Syria. A great part of this
+material is thrown out again by the waves on the European shores of that
+sea. The harbors of Luni, Albenga, San Remo, and Savona west of Genoa,
+and of Porto Fino on the other side, are filling up, and the coast near
+Carrara and Massa is said to have advanced upon the sea to a distance
+of 475 feet in thirty-three years.[413] Besides this, we have no
+evidence of the existence of deep-water currents in the Mediterranean,
+extensive enough and strong enough to transport quartzose sand across
+the sea. It may be added that much of the rock from which the torrent
+sands of Southern Europe are derived contains little quartz, and hence
+the general character of these sands is such that they must be
+decomposed or ground down to an impalpable slime, long before they could
+be swept over to the African shore.
+
+The torrents of Europe, then, do not at present furnish the material
+which composes the beach sands of Northern Africa, and it is equally
+certain that those sands are not brought down by the rivers of the
+latter continent. They belong to a remote geological period, and have
+been accumulated by causes which we cannot at present assign. The wind
+does not stir water to great depths with sufficient force to disturb the
+bottom,[414] and the sand thrown upon the coast in question must be
+derived from a narrow belt of sea. It must hence, in time, become
+exhausted, and the formation of new sandbanks and dunes upon the
+southern shores of the Mediterranean will cease at last for want of
+material.[415]
+
+But even in the cases where the accumulations of sand in extensive
+deserts appear to be of marine formation, or rather aggregation, and to
+have been brought to their present position by upheaval, they are not
+wholly composed of material collected or distributed by the currents of
+the sea; for, in all such regions, they continue to receive some small
+contributions from the disintegration of the rocks which underlie, or
+crop out through, the superficial deposits. In some instances, too, as
+in Northern Africa, additions are constantly made to the mass by the
+prevalence of sea winds, which transport, or, to speak more precisely,
+roll the finer beach sand to considerable distances into the interior.
+But this is a very slow process, and the exaggerations of travellers
+have diffused a vast deal of popular error on the subject.
+
+
+_Sands of Egypt._
+
+In the narrow valley of the Nile--which, above its bifurcation near
+Cairo, is, throughout Egypt and Nubia, generally bounded by precipitous
+cliffs--wherever a ravine or other considerable depression occurs in the
+wall of rock, one sees what seems a stream of desert sand pouring down,
+and common observers have hence concluded that the whole valley is in
+danger of being buried under a stratum of infertile soil. The ancient
+Egyptians apprehended this, and erected walls, often of unburnt brick,
+across the outlet of gorges and lateral valleys, to check the flow of
+the sand streams. In later ages, these walls have mostly fallen into
+decay, and no preventive measures against such encroachments are now
+resorted to. But the extent of the mischief to the soil of Egypt, and
+the future danger from this source, have been much overrated. The sand
+on the borders of the Nile is neither elevated so high by the wind, nor
+transported by that agency in so great masses, as is popularly supposed;
+and of that which is actually lifted or rolled and finally deposited by
+air currents, a considerable proportion is either calcareous, and,
+therefore, readily decomposable, or in the state of a very fine dust,
+and so, in neither case, injurious to the soil. There are, indeed, both
+in Africa and in Arabia, considerable tracts of fine silicious sand,
+which may be carried far by high winds, but these are exceptional cases,
+and in general the progress of the desert sand is by a rolling motion
+along the surface.[416] So little is it lifted, and so inconsiderable
+is the quantity yet remaining on the borders of Egypt, that a wall four
+or five feet high suffices for centuries to check its encroachments.
+This is obvious to the eye of every observer who prefers the true to the
+marvellous; but the old-world fable of the overwhelming of caravans by
+the fearful simoom--which, even the Arabs no longer repeat, if indeed
+they are the authors of it--is so thoroughly rooted in the imagination
+of Christendom that most desert travellers, of the tourist class, think
+they shall disappoint the readers of their journals if they do not
+recount the particulars of their escape from being buried alive by a
+sand storm, and the popular demand for a "sensation" must be gratified
+accordingly.[417]
+
+Another circumstance is necessary to be considered in estimating the
+danger to which the arable lands of Egypt are exposed. The prevailing
+wind in the valley of the Nile and its borders is from the north, and it
+may be said without exaggeration that the north wind blows for three
+quarters of the year.[418] The effect of winds blowing up the valley is
+to drive the sands of the desert plateau which border it, in a direction
+parallel with the axis of the valley, not transversely to it; and if it
+ran in a straight line, the north wind would carry no desert sand into
+it. There are, however, both curves and angles in its course, and hence,
+wherever its direction deviates from that of the wind, it might receive
+sand drifts from the desert plain through which it runs. But, in the
+course of ages, the winds have, in a great measure, bared the projecting
+points of their ancient deposits, and no great accumulations remain in
+situations from which either a north or a south wind would carry them
+into the valley.[419]
+
+
+_The Suez Canal._
+
+These considerations apply, with equal force, to the supposed danger of
+the obstruction of the Suez Canal by the drifting of the desert sands.
+The winds across the isthmus are almost uniformly from the north, and
+they swept it clean of flying sands long ages since. The traces of the
+ancient canal between the Red Sea and the Nile are easily followed for a
+considerable distance from Suez. Had the drifts upon the isthmus been as
+formidable as some have feared and others have hoped, those traces would
+have been obliterated, and Lake Timsah and the Bitter Lakes filled up,
+many centuries ago. The few particles driven by the rare east and west
+winds toward the line of the canal, would easily be arrested by
+plantations or other simple methods, or removed by dredging. The real
+dangers and difficulties of this magnificent enterprise--and they are
+great--consist in the nature of the soil to be removed in order to form
+the line, and especially in the constantly increasing accumulation of
+sea sand at the southern terminus by the tides of the Red Sea, and at
+the northern, by the action of the winds. Both seas are shallow for
+miles from the shore, and the excavation and maintenance of deep
+channels, and of capacious harbors with easy and secure entrances, in
+such localities, is doubtless one of the hardest problems offered to
+modern engineers for practical solution.
+
+
+_Sands of Egypt._
+
+The sand let fall in Egypt by the north wind is derived, not from the
+desert, but from a very different source--the sea. Considerable
+quantities of sand are thrown up by the Mediterranean, at and between
+the mouths of the Nile, and indeed along almost the whole southern coast
+of that sea, and drifted into the interior to distances varying
+according to the force of the wind and the abundance and quality of the
+material. The sand so transported contributes to the gradual elevation
+of the Delta, and of the banks and bed of the river itself. But just in
+proportion as the bed of the stream is elevated, the height of the water
+in the annual inundations is increased also, and as the inclination of
+the channel is diminished, the rapidity of the current is checked, and
+the deposition of the slime it holds in suspension consequently
+promoted. Thus the winds and the water, moving in contrary directions,
+join in producing a common effect.
+
+The sand, blown over the Delta and the cultivated land higher up the
+stream during the inundation, is covered or mixed with the fertile earth
+brought down by the river, and no serious injury is sustained from it.
+That spread over the same ground after the water has subsided, and
+during the short period when the soil is not stirred by cultivation or
+covered by the flood, forms a thin pellicle over the surface as far as
+it extends, and serves to divide and distinguish the successive layers
+of slime deposited by the annual inundations. The particles taken up by
+the wind on the sea beach are borne onward, by a hopping motion, or
+rolled along the surface, until they are arrested by the temporary
+cessation of the wind, by vegetation, or by some other obstruction, and
+they may, in process of time, accumulate in large masses, under the lee
+of rocky projections, buildings, or other barriers which break the force
+of the wind.
+
+In these facts we find the true explanation of the sand drifts, which
+have half buried the Sphinx and so many other ancient monuments in that
+part of Egypt. These drifts, as I have said, are not primarily from the
+desert, but from the sea; and, as might be supposed from the distance
+they have travelled, they have been long in gathering. While Egypt was a
+great and flourishing kingdom, measures were taken to protect its
+territory against the encroachment of sand, whether from the desert or
+from the sea; but the foreign conquerors, who destroyed so many of its
+religious monuments, did not spare its public works, and the process of
+physical degradation undoubtedly began as early as the Persian invasion.
+The urgent necessity, which has compelled all the successive tyrannies
+of Egypt to keep up some of the canals and other arrangements for
+irrigation, was not felt with respect to the advancement of the sands;
+for their progress was so slow as hardly to be perceptible in the course
+of a single reign, and long experience has shown that, from the natural
+effect of the inundations, the cultivable soil of the valley is, on the
+whole, trenching upon the domain of the desert, not retreating before
+it.
+
+The oases of the Libyan, as well as of many Asiatic deserts, have no
+such safeguards. The sands are fast encroaching upon them, and threaten
+soon to engulf them, unless man shall resort to artesian wells and
+plantations, or to some other efficient means of checking the advance of
+this formidable enemy, in time to save these islands of the waste from
+final destruction.
+
+Accumulations of sand are, in certain cases, beneficial as a protection
+against the ravages of the sea; but, in general, the vicinity, and
+especially the shifting of bodies of this material, are destructive to
+human industry, and hence, in civilized countries, measures are taken to
+prevent its spread. This, however, can be done only where the population
+is large and enlightened, and the value of the soil, or of the
+artificial erections and improvements upon it, is considerable. Hence in
+the deserts of Africa and of Asia, and the inhabited lands which border
+on them, no pains are usually taken to check the drifts, and when once
+the fields, the houses, the springs, or the canals of irrigation are
+covered or choked, the district is abandoned without a struggle, and
+surrendered to perpetual desolation.[420]
+
+
+_Sand Dunes and Sand Plains._
+
+Two forms of sand deposit are specially important in European and
+American geography. The one is that of dune or shifting hillock upon the
+coast, the other that of barren plain in the interior. The coast dunes
+are composed of sand washed up from the depths of the sea by the waves,
+and heaped in knolls and ridges by the winds. The sand with which many
+plains are covered, appears sometimes to have been deposited upon them
+while they were yet submerged, sometimes to have been drifted from the
+sea coast, and scattered over them by wind currents, sometimes to have
+been washed upon them by running water. In these latter cases, the
+deposit, though in itself considerable, is comparatively narrow in
+extent and irregular in distribution, while, in the former, it is often
+evenly spread over a very wide surface. In all great bodies of either
+sort, the silicious grains are the principal constituent, though, when
+not resulting from the disintegration of silicious rock and still
+remaining in place, they are generally accompanied with a greater or
+less admixture of other mineral particles, and of animal and vegetable
+remains,[421] and they are, also, usually somewhat changed in
+consistence by the ever-varying conditions of temperature and moisture
+to which they have been exposed since their deposit. Unless the
+proportion of these latter ingredients is so large as to create a
+certain adhesiveness in the mass--in which case it can no longer
+properly be called sand--it is infertile, and, if not charged with
+water, partially agglutinated by iron, lime, or other cement, or
+confined by alluvion resting upon it, it is much inclined to drift,
+whenever, by any chance, the vegetable network which, in most cases,
+thinly clothes and at the same time confines it, is broken.
+
+Human industry has not only fixed the flying dunes, but, by mixing clay
+and other tenacious earths with the superficial stratum of extensive
+sand plains, and by the application of fertilizing substances, it has
+made them abundantly productive of vegetable life. These latter
+processes belong to agriculture and not to geography, and, therefore,
+are not embraced within the scope of the present subject. But the
+preliminary steps, whereby wastes of loose, drifting barren sands are
+transformed into wooded knolls and plains, and finally, through the
+accumulation of vegetable mould, into arable ground, constitute a
+conquest over nature which precedes agriculture--a geographical
+revolution--and, therefore, an account of the means by which the change
+has been effected belongs properly to the history of man's influence on
+the great features of physical geography. I proceed, then, to examine
+the structure of dunes, and to describe the warfare man wages with the
+sand hills, striving on the one hand to maintain and even extend them,
+as a natural barrier against encroachments of the sea, and, on the
+other, to check their moving and wandering propensities, and prevent
+them from trespassing upon the fields he has planted and the habitations
+in which he dwells.
+
+
+_Coast Dunes._
+
+Coast dunes are oblong ridges or round hillocks, formed by the action of
+the wind upon sands thrown up by the waves on the beach of seas, and
+sometimes of fresh-water lakes. On most coasts, the supply of sand for
+the formation of dunes is derived from tidal waves. The flow of the tide
+is more rapid, and consequently its transporting power greater, than
+that of the ebb; the momentum, acquired by the heavy particles in
+rolling in with the water, tends to carry them even beyond the flow of
+the waves; and at the turn of the tide, the water is in a state of
+repose long enough to allow it to let fall much of the solid matter it
+holds in suspension. Hence, on all low, tide-washed coasts of seas with
+sandy bottoms, there exist several conditions favorable to the formation
+of sand deposits along high-water mark.[422] If the land winds are of
+greater frequency, duration, or strength than the sea winds, the sands
+left by the retreating wave will be constantly blown back into the
+water; but if the prevailing air currents are in the opposite direction,
+the sands will soon be carried out of the reach of the highest waves,
+and transported continually farther and farther into the interior of the
+land, unless obstructed by high grounds, vegetation, or other obstacles.
+
+The tide, though a usual, is by no means a necessary condition for the
+accumulations of sand out of which dunes are formed. The Baltic and the
+Mediterranean are almost tideless seas, but there are dunes on the
+Russian and Prussian coasts of the Baltic, and at the mouths of the Nile
+and many other points on the shores of the Mediterranean. The vast
+shoals in the latter sea, known to the ancients as the Greater and
+Lesser Syrtis, are of marine origin. They are still filling up with
+sand, washed up from greater depths, or sometimes drifted from the coast
+in small quantities, and will probably be converted, at some future
+period, into dry land covered with sand hills. There are also extensive
+ranges of dunes upon the eastern shores of the Caspian, and at the
+southern, or rather southeastern extremity of Lake Michigan.[423] There
+is no doubt that this latter lake formerly extended much farther in that
+direction, but its southern portion has gradually shoaled and at last
+been converted into solid land, in consequence of the prevalence of the
+northwest winds. These blow over the lake a large part of the year, and
+create a southwardly set of the currents, which wash up sand from the
+bed of the lake and throw it on shore. Sand is taken up from the beach
+at Michigan City by every wind from that quarter, and, after a heavy
+blow of some hours' duration, sand ridges may be observed on the north
+side of the fences, like the snow wreaths deposited by a drifting wind
+in winter. Some of the particles are carried back by contrary winds, but
+most of them lodge on or behind the dunes, or in the moist soil near the
+lake, or are entangled by vegetables, and tend permanently to elevate
+the level. Like effects are produced by constant sea winds, and dunes
+will generally be formed on all low coasts where such prevail, whether
+in tideless or in tidal waters.
+
+Jobard thus describes the _modus operandi_, under ordinary
+circumstances, at the mouths of the Nile, where a tide can scarcely be
+detected: "When a wave breaks, it deposits an almost imperceptible line
+of fine sand. The next wave brings also its contribution, and shoves the
+preceding line a little higher. As soon as the particles are fairly out
+of the reach of the water they are dried by the heat of the burning sun,
+and immediately seized by the wind and rolled or borne farther inland.
+The gravel is not thrown out by the waves, but rolls backward and
+forward until it is worn down to the state of fine sand, when it, in its
+turn, is cast upon the land and taken up by the wind."[424] This
+description applies only to the common every-day action of wind and
+water; but just in proportion to the increasing force of the wind and
+the waves, there is an increase in the quantity of sand, and in the
+magnitude of the particles carried off from the beach by it, and, of
+course, every storm in a landward direction adds sensibly to the
+accumulation upon the shore.
+
+
+_Sand Banks._
+
+Although dunes, properly so called, are found only on dry land and above
+ordinary high-water mark, and owe their elevation and structure to the
+action of the wind, yet, upon many shelving coasts, accumulations of
+sand much resembling dunes are formed under water at some distance from
+the shore by the oscillations of the waves, and are well known by the
+name of sand banks. They are usually rather ridges than banks, of
+moderate inclination, and with the steepest slope seaward; and their
+form differs from that of dunes only in being lower and more continuous.
+Upon the western coast of the island of Amrum, for example, there are
+three rows of such banks, the summits of which are at a distance of
+perhaps a couple of miles from each other; so that, including the width
+of the banks themselves, the spaces between them, and the breadth of the
+zone of dunes upon the land, the belt of moving sands on that coast is
+probably not less than eight miles wide.
+
+Under ordinary circumstances, sand banks are always rolling landward,
+and they compose the magazine from which the material for the dunes is
+derived. The dunes, in fact, are but aquatic sand banks transferred to
+dry land. The laws of their formation are closely analogous, because the
+action of the two fluids, by which they are respectively accumulated and
+built up, is very similar when brought to bear upon loose particles of
+solid matter. It would, indeed, seem that the slow and comparatively
+regular movements of the heavy, unelastic water ought to affect such
+particles very differently from the sudden and fitful impulses of the
+light and elastic air. But the velocity of the wind currents gives them
+a mechanical force approximating to that of the slower waves, and,
+however difficult it may be to explain all the phenomena that
+characterize the structure of the dunes, observation has proved that it
+is nearly identical with that of submerged sand banks. The differences
+of form are generally ascribable to the greater number and variety of
+surface accidents of the ground on which the sand hills of the land are
+built up, and to the more frequent changes, and wider variety of
+direction, in the courses of the wind.
+
+
+_Dunes on the Coast of America._
+
+Upon the Atlantic coast of the United States, the prevalence of western
+or off-shore winds is unfavorable to the formation of dunes, and, though
+marine currents lodge vast quantities of sand, in the form of banks, on
+that coast, its shores are proportionally more free from sand hills than
+some others of lesser extent. There are, however, very important
+exceptions. The action of the tide throws much sand upon some points of
+the New England coast, as well as upon the beaches of Long Island and
+other more southern shores, and here dunes resembling those of Europe
+are formed. There are also extensive ranges of dunes on the Pacific
+coast of the United States, and at San Francisco they border some of the
+streets of the city.
+
+The dunes of America are far older than her civilization, and the soil
+they threaten or protect possesses, in general, too little value to
+justify any great expenditure in measures for arresting their progress
+or preventing their destruction. Hence, great as is their extent and
+their geographical importance, they have, at present, no such intimate
+relations to human life as to render them objects of special interest in
+the point of view I am taking, and I do not know that the laws of their
+formation and motion have been made a subject of original investigation
+by any American observer.
+
+
+_Dunes of Western Europe._
+
+Upon the western coast of Europe, on the contrary, the ravages
+occasioned by the movement of sand dunes, and the serious consequences
+often resulting from the destruction of them, have long engaged the
+earnest attention of governments and of scientific men, and for nearly a
+century persevering and systematic effort has been made to bring them
+under human control. The subject has been carefully studied in Denmark
+and the adjacent duchies, in Western Prussia, in the Netherlands, and in
+France; and the experiments in the way of arresting the drifting of the
+dunes, and of securing them, and the lands they shelter, from the
+encroachments of the sea, have resulted in the adoption of a system of
+coast improvement substantially the same in all these countries. The
+sands, like the forests, have now their special literature, and the
+volumes and memoirs, which describe them and the processes employed to
+subdue them, are full of scientific interest and of practical
+instruction.[425]
+
+
+_Formation of Dunes._
+
+The laws which govern the formation of dunes are substantially these. We
+have seen that, under certain conditions, sand is accumulated above
+high-water mark on low sea and lake shores. So long as the sand is kept
+wet by the spray or by capillary attraction, it is not disturbed by air
+currents, but as soon as the waves retire sufficiently to allow it to
+dry, it becomes the sport of the wind, and is driven up the gently
+sloping beach until it is arrested by stones, vegetables, or other
+obstructions, and thus an accumulation is formed which constitutes the
+foundation of a dune. However slight the elevation thus created, it
+serves to stop or retard the progress of the sand grains which are
+driven against its shoreward face, and to protect from the further
+influence of the wind the particles which are borne beyond it, or rolled
+over its crest, and fall down behind it. If the shore above the beach
+line were perfectly level and straight, the grass or bushes upon it of
+equal height, the sand thrown up by the waves uniform in size and weight
+of particles as well as in distribution, and if the action of the wind
+were steady and regular, a continuous bank would be formed, everywhere
+alike in height and cross section. But no such constant conditions
+anywhere exist. The banks are curved, broken, unequal in elevation; they
+are sometimes bare, sometimes clothed with vegetables of different
+structure and dimensions; the sand thrown up is variable in quantity and
+character; and the winds are shifting, gusty, vortical, and often
+blowing in very narrow currents. From all these causes, instead of
+uniform hills, there rise irregular rows of sand heaps, and these, as
+would naturally be expected, are of a pyramidal, or rather conical
+shape, and connected at bottom by more or less continuous ridges of the
+same material.
+
+On a receding coast, dunes will not attain so great a height as on more
+secure shores, because they are undermined and carried off before they
+have time to reach their greatest dimensions. Hence, while at sheltered
+points in Southwestern France, there are dunes three hundred feet or
+more in height, those on the Frisic Islands and the exposed parts of the
+coast of Schleswig-Holstein range only from twenty to one hundred feet.
+On the western shores of Africa, it is said that they sometimes attain
+an elevation of six hundred feet. This is one of the very few points
+known to geographers where desert sands are advancing seaward, and here
+they rise to the greatest altitude to which sand grains can be carried
+by the wind.
+
+The hillocks, once deposited, are held together and kept in shape,
+partly by mere gravity, and partly by the slight cohesion of the lime,
+clay, and organic matter mixed with the sand; and it is observed that,
+from capillary attraction, evaporation from lower strata, and retention
+of rain water, they are always moist a little below the surface.[426] By
+successive accumulations, they gradually rise to the height of thirty,
+fifty, sixty, or a hundred feet, and sometimes even much higher. Strong
+winds, instead of adding to their elevation, sweep off loose particles
+from their surface, and these, with others blown over or between them,
+build up a second row of dunes, and so on according to the character of
+the wind, the supply and consistence of the sand, and the face of the
+country. In this way is formed a belt of sand dunes, irregularly
+dispersed and varying much in height and dimensions, and some times many
+miles in breadth. On the Island of Sylt, in the German Sea, where there
+are several rows, the width of the belt is from half a mile to a mile.
+There are similar ranges on the coast of Holland, exceeding two miles in
+breadth, while at the mouths of the Nile they form a zone not less than
+ten miles wide. The base of some of the dunes in the Delta of the Nile
+is reached by the river during the annual inundation, and the
+infiltration of the water, which contains lime, has converted the lower
+strata into a silicious limestone, or rather a calcareous sandstone, and
+thus afforded an opportunity of studying the structure of that rock in a
+locality where its origin and mode of aggregation and solidification are
+known.
+
+
+_Character of Dune Sand._
+
+"Dune sand," says Staring, "consists of well-rounded grains of quartz,
+more or less colored by iron, and often mingled with fragments of
+shells, small indeed, but still visible to the naked eye.[427] These
+fragments are not constant constituents of dune sand. They are sometimes
+found at the very summits of the hillocks, as at Overveen; in the King's
+Dune, near Egmond, they form a coarse calcareous gravel very largely
+distributed through the sand, while the interior dunes between Haarlem
+and Warmond exhibit no trace of them. It is yet undecided whether the
+presence or absence of these fragments is determined by the period of
+the formation of the dunes, or whether it depends on a difference in the
+process by which different dunes have been accumulated. Land shells,
+such as snails, for example, are found on the surface of the dunes in
+abundance, and many of the shelly fragments in the interior of the
+hillocks may be derived from the same source."[428]
+
+J. G. Kohl has some poetical thoughts upon the origin and character of
+the dune sands, which are worth quoting:
+
+"The sand was composed of pure transparent quartz. I could not observe
+this sand without the greatest admiration. If it is the product of the
+waves, breaking and crushing flints and fragments of quartz against each
+other, it is a result which could be brought about only in the course of
+countless ages. We need not lift ourselves to the stars, to their
+incalculable magnitudes and distances and numbers, in order to feel the
+giddiness of astonishment. Here, upon earth, in the simple sand, we find
+miracle enough. Think of the number of sand grains contained in a single
+dune, then of all the dunes upon this widely extended coast--not to
+speak of the innumerable grains in the Arabian, African, and Prussian
+deserts--this, of itself, is sufficient to overwhelm a thoughtful fancy.
+How long, how many times must the waves have risen and sunk in order to
+reduce these vast heaps to powder!
+
+"During the whole time I spent on this coast, I had always some sand in
+my fingers, was rubbing and rolling it about, examining it on all sides,
+holding a little shining grain on the tip of my finger, and thinking to
+myself how, in its corners, its angles, its whole configuration, it
+might very probably have a history longer than that of the old German
+nation--possibly longer than that of the human race. Where was the
+original quartz crystal, of which this is a fragment, first formed? To
+what was it once fixed? What power broke it loose? How was it beaten
+smaller and ever smaller by the waves? They tossed it, for aeons, to and
+fro upon the beach, rolled it up and down, forced it to make thousands
+and thousands of daily voyages for millions and millions of days. Then
+the wind bore it away, and used it in building up a dune; there it lay
+for centuries, packed in with its fellows, protecting the marshes and
+cherished by the inhabitants, till, seized again by the pursuing sea, it
+fell once more into the water, there to begin the endless dance
+anew--and again to be swept away by the wind--and again to find rest in
+the dunes, a protection and a blessing to the coast. There is something
+mysterious about such a grain of sand, and at last I went so far as to
+fancy a little immortal spark linked with each one, presiding over its
+destiny, and sharing its vicissitudes. Could we arm our eyes with a
+microscope, and then dive, like a sparling, into one of these dunes, the
+pile, which is in fact only a heap of countless little crystal blocks,
+would strike us as the most marvellous building upon earth. The sunbeams
+would pass, with illuminating power, through all these little
+crystalline bodies. We should see how every sand grain is formed, by
+what multifarious little facets it is bounded, we should even discover
+that it is itself composed of many distinct particles."[429]
+
+Sand concretions form within the dunes and especially in the depressions
+between them. These are sometimes so extensive and impervious as to
+retain a sufficient supply of water to feed perennial springs, and to
+form small permanent ponds, and they are a great impediment to the
+penetration of roots, and consequently to the growth of trees planted,
+or germinating from self-sown seeds, upon the dunes.[430]
+
+
+_Interior Structure of Dunes._
+
+The interior structure of the dunes, the arrangement of their particles,
+is not, as might be expected, that of an unorganized, confused heap, but
+they show a strong tendency to stratification. This is a point of much
+geological interest, because it indicates that sandstone may owe its
+stratified character to the action of wind as well as of water. The
+origin and peculiar character of these layers are due to a variety of
+causes. A southwest wind and current may deposit upon a dune a stratum
+of a given color and mineral composition, and this may be succeeded by a
+northwest wind and current, bringing with them particles of a different
+hue, constitution, and origin.
+
+Again, if we suppose a violent tempest to strew the beach with sand
+grains very different in magnitude and specific gravity, and, after the
+sand is dry, to be succeeded by a gentle breeze, it is evident that only
+the lighter particles will be taken up and carried to the dunes. If,
+after some time, the wind freshens, heavier grains will be transported
+and deposited on the former, and a still stronger succeeding gale will
+roll up yet larger kernels. Each of these deposits will form a stratum.
+If we suppose the tempest to be followed, after the sand is dry, not by
+a gentle breeze, but by a wind powerful enough to lift at the same time
+particles of very various magnitudes and weights, the heaviest will
+often lodge on the dune while the lighter will be carried farther. This
+would produce a stratum of coarse sand, and the same effect might result
+from the blowing away of light particles out of a mixed layer, while the
+heavier remained undisturbed.[431] Still another cause of
+stratification may be found in the occasional interposition of a thin
+layer of leaves or other vegetable remains between successive deposits,
+and this I imagine to be more frequent than has been generally supposed.
+
+The eddies of strong winds between the hillocks must also occasion
+disturbances and re-arrangements of the sand layers, and it seems
+possible that the irregular thickness and the strange contortions of the
+strata of the sandstone at Petra may be due to some such cause. A
+curious observation of Professor Forchhammer suggests an explanation of
+another peculiarity in the structure of the sandstone of Mount Seir. He
+describes dunes in Jutland, composed of yellow quartzose sand intermixed
+with black titanian iron. When the wind blows over the surface of the
+dunes, it furrows the sand with alternate ridges and depressions,
+ripples, in short, like those of water. The swells, the dividing ridges
+of the system of sand ripples, are composed of the light grains of
+quartz, while the heavier iron rolls into the depressions between, and
+thus the whole surface of the dune appears as if covered with a fine
+black network.
+
+
+_Form of Dunes._
+
+The sea side of dunes, being more exposed to the caprices of the wind,
+is more irregular in form than the lee or land side, where the
+arrangement of the particles is affected by fewer disturbing and
+conflicting influences. Hence, the stratification of the windward slope
+is somewhat confused, while the sand on the lee side is found to be
+disposed in more regular beds, inclining landward, and with the largest
+particles lowest, where their greater weight would naturally carry them.
+The lee side of the dunes, being thus formed of sand deposited according
+to the laws of gravity, is very uniform in its slope, which, according
+to Forchhammer, varies little from an angle of 30 deg. with the horizon,
+while the more exposed and irregular weather side lies at an inclination
+of from 5 deg. to 10 deg.. When, however, the outer tier of dunes is formed so
+near the waterline as to be exposed to the immediate action of the
+waves, it is undermined, and the face of the hill is very steep and
+sometimes nearly perpendicular.
+
+
+_Geological Importance of Dunes._
+
+These observations, and other facts which a more attentive study on the
+spot would detect, might furnish the means of determining interesting
+and important questions concerning geological formations in localities
+very unlike those where dunes are now thrown up. For example, Studer
+supposes that the drifting sand hills of the African desert were
+originally coast dunes, and that they have been transported to their
+present position far in the interior, by the rolling and shifting
+leeward movement to which all dunes not covered with vegetation are
+subject. The present general drift of the sands of that desert appears
+to be to the southwest and west, the prevailing winds blowing from the
+northeast and east; but it has been doubted whether the shoals of the
+western coast of Northern Africa, and the sands upon that shore, are
+derived from the bottom of the Atlantic, in the usual manner, or, by an
+inverse process, from those of the Sahara. The latter, as has been
+before remarked, is probably the truth, though observations are wanting
+to decide the question.[432] There is nothing violently improbable in
+the supposition that they may have been first thrown up by the
+Mediterranean on its Libyan coast, and thence blown south and west over
+the vast space they now cover. But whatever has been their source and
+movement, they can hardly fail to have left on their route some
+sandstone monuments to mark their progress, such, for example, as we
+have seen are formed from the dune sand at the mouth of the Nile; and it
+is conceivable that the character of the drifting sands themselves, and
+of the conglomerates and sandstones to whose formation they have
+contributed, might furnish satisfactory evidence as to their origin,
+their starting point, and the course by which they have wandered so far
+from the sea.[433]
+
+If the sand of coast dunes is, as Staring describes it, composed chiefly
+of well-rounded quartzose grains, fragments of shells, and other
+constant ingredients, it would often be recognizable as coast sand, in
+its agglutinate state of sandstone. The texture of this rock varies from
+an almost imperceptible fineness of grain to great coarseness, and
+affords good facilities for microscopic observation of its structure.
+There are sandstones, such, for example, as are used for grindstones,
+where the grit, as it is called, is of exceeding sharpness; others where
+the angles of the grains are so obtuse that they scarcely act at all on
+hard metals. The former may be composed of grains of rock, disintegrated
+indeed, and recemented together, but not, in the meanwhile, much rolled;
+the latter, of sands long washed by the sea, and drifted by land winds.
+There is, indeed, so much resemblance between the effects of driving
+winds and of rolling water upon light bodies, that there would be
+difficulty in distinguishing them;[434] but after all, it is not
+probable that sandstone, composed of grains thrown up from the salt sea,
+and long tossed by the winds, would be identical in its structure with
+that formed from fragments of rock crushed by mechanical force, or
+disintegrated by heat, and again agglutinated without much exposure to
+the action of moving water.[435]
+
+
+_Inland Dunes._
+
+I have met with some observations indicating a structural difference
+between interior and coast dunes, which might perhaps be recognized in
+the sandstones formed from these two species of sand hills respectively.
+In the great American desert between the Andes and the Pacific, Meyen
+found sand heaps of a perfect falciform shape.[436] They were from seven
+to fifteen feet high, the chord of their arc measuring from twenty to
+seventy paces. The slope of the convex face is described as very small,
+that of the concave as high as 70 deg. or 80 deg., and their surfaces were
+rippled. No smaller dunes were observed, nor any in the process of
+formation. The concave side uniformly faced the northwest, except toward
+the centre of the desert, where, for a distance of one or two hundred
+paces, they gradually opened to the west, and then again gradually
+resumed the former position.
+
+Poeppig ascribes a falciform shape to the movable, a conical to the fixed
+dunes, or _medanos_, of the same desert. "The medanos," he observes,
+"are hillock-like elevations of sand, some having a firm, others a loose
+base. The former [latter], which are always crescent shaped, are from
+ten to twenty feet high, and have an acute crest. The inner side is
+perpendicular, and the outer or bow side forms an angle with a steep
+inclination downward. When driven by violent winds, the medanos pass
+rapidly over the plains. The smaller and lighter ones move quickly
+forward, before the larger; but the latter soon overtake and crush them,
+whilst they are themselves shivered by the collision. These medanos
+assume all sorts of extraordinary figures, and sometimes move along the
+plain in rows forming most intricate labyrinths. * * A plain often
+appears to be covered with a row of medanos, and some days afterward it
+is again restored to its level and uniform aspect. * * *
+
+"The medanos with immovable bases are formed on the blocks of rocks
+which are scattered about the plain. The sand is driven against them by
+the wind, and as soon as it reaches the top point, it descends on the
+other side until that is likewise covered; thus gradually arises a
+conical-formed hill. Entire hillock chains with acute crests are formed
+in a similar manner. * * * On their southern declivities are found vast
+masses of sand, drifted thither by the mid-day gales. The northern
+declivity, though not steeper than the southern, is only sparingly
+covered with sand. If a hillock chain somewhat distant from the sea
+extends in a line parallel with the Andes, namely, from S. S. E. to N.
+N. W., the western declivity is almost entirely free of sand, as it is
+driven to the plain below by the southeast wind, which constantly
+alternates with the wind from the south."[437]
+
+It is difficult to reconcile this description with that of Meyen, but if
+confidence is to be reposed in the accuracy of either observer, the
+formation of the sand hills in question must be governed by very
+different laws from those which determine the structure of coast dunes.
+Captain Gilliss, of the American navy, found the sand hills of the
+Peruvian desert to be in general crescent shaped, as described by Meyen,
+and a similar structure is said to characterize the inland dunes of the
+Llano Estacado and other plateaus of the North American desert, though
+these latter are of greater height and other dimensions than those
+described by Meyen. There is no very obvious explanation of this
+difference in form between maritime and inland sand hills, and the
+subject merits investigation.[438]
+
+
+_Age, Character, and Permanence of Dunes._
+
+The origin of most great lines of dunes goes back past all history.
+There are on many coasts, several distinct ranges of sand hills which
+seem to be of very different ages, and to have been formed under
+different relative conditions of land and water.[439] In some cases,
+there has been an upheaval of the coast line since the formation of the
+oldest hillocks, and these have become inland dunes, while younger rows
+have been thrown up on the new beach laid bare by elevation of the sea
+bed. Our knowledge of the mode of their first accumulation is derived
+from observation of the action of wind and water in the few instances
+where, with or without the aid of man, new coast dunes have been
+accumulated, and of the influence of wind alone in elevating new sand
+heaps inland of the coast tier, when the outer rows are destroyed by the
+sea, as also when the sodded surface of ancient sands has been broken,
+and the subjacent strata laid open to the air.
+
+It is a question of much interest, in what degree the naked condition of
+most dunes is to be ascribed to the improvidence and indiscretion of
+man. There are, in Western France, extensive ranges of dunes covered
+with ancient and dense forests, while the recently formed sand hills
+between them and the sea are bare of vegetation, and are rapidly
+advancing upon the wooded dunes, which they threaten to bury beneath
+their drifts. Between the old dunes and the new, there is no
+discoverable difference in material or in structure; but the modern sand
+hills are naked and shifting, the ancient, clothed with vegetation and
+fixed. It has been conjectured that artificial methods of confinement
+and plantation were employed by the primitive inhabitants of Gaul; and
+Laval, basing his calculations on the rate of annual movement of the
+shifting dunes, assigns the fifth century of the Christian era as the
+period when these processes were abandoned.[440]
+
+There is no historical evidence that the Gauls were acquainted with
+artificial methods of fixing the sands of the coast, and we have little
+reason to suppose that they were advanced enough in civilization to be
+likely to resort to such processes, especially at a period when land
+could have had but a moderate value.
+
+In other countries, dunes have spontaneously clothed themselves with
+forests, and the rapidity with which their surface is covered by various
+species of sand plants, and finally by trees, where man and cattle and
+burrowing animals are excluded from them, renders it highly probable
+that they would, as a general rule, protect themselves, if left to the
+undisturbed action of natural causes. The sand hills of the Frische
+Nehrung, on the coast of Prussia, were formerly wooded down to the
+water's edge, and it was only in the last century that, in consequence
+of the destruction of their forests, they became moving sands.[441]
+There is every reason to believe that the dunes of the Netherlands were
+clothed with trees until after the Roman invasion. The old geographers,
+in describing these countries, speak of vast forests extending to the
+very brink of the sea; but drifting coast dunes are first mentioned by
+the chroniclers of the Middle Ages, and so far as we know they have
+assumed a destructive character in consequence of the improvidence of
+man.[442] The history of the dunes of Michigan, so far as I have been
+able to learn from my own observation, or that of others, is the same.
+Thirty years ago, when that region was scarcely inhabited, they were
+generally covered with a thick growth of trees, chiefly pines, and
+underwood, and there was little appearance of undermining and wash on
+the lake side, or of shifting of the sands, except where the trees had
+been cut or turned up by the roots.[443]
+
+Nature, as she builds up dunes for the protection of the sea shore,
+provides, with similar conservatism, for the preservation of the dunes
+themselves; so that, without the interference of man, these hillocks
+would be, not perhaps absolutely perpetual, but very lasting in
+duration, and very slowly altered in form or position. When once covered
+with the trees, shrubs, and herbaceous growths adapted to such
+localities, dunes undergo no apparent change, except the slow occasional
+undermining of the outer tier, and accidental destruction by the
+exposure of the interior, from the burrowing of animals, or the
+upturning of trees with their roots, and all these causes of
+displacement are very much less destructive when a vegetable covering
+exists in the immediate neighborhood of the breach.
+
+Before the occupation of the coasts by civilized and therefore
+destructive man, dunes, at all points where they have been observed,
+seem to have been protected in their rear by forests, which served to
+break the force of the winds in both directions,[444] and to have
+spontaneously clothed themselves with a dense growth of the various
+plants, grasses, shrubs, and trees, which nature has assigned to such
+soils. It is observed in Europe that dunes, though now without the
+shelter of a forest country behind them, begin to protect themselves as
+soon as human trespassers are excluded, and grazing animals denied
+access to them. Herbaceous and arborescent plants spring up almost at
+once, first in the depressions, and then upon the surface of the sand
+hills. Every seed that sprouts, binds together a certain amount of sand
+by its roots, shades a little ground with its leaves, and furnishes food
+and shelter for still younger or smaller growths. A succession of a very
+few favorable seasons suffices to bind the whole surface together with a
+vegetable network, and the power of resistance possessed by the dunes
+themselves, and the protection they afford to the fields behind them,
+are just in proportion to the abundance and density of the plants they
+support.
+
+The growth of the vegetable covering can, of course, be much accelerated
+by judicious planting and watchful care, and this species of improvement
+is now carried on upon a vast scale, wherever the value of land is
+considerable and the population dense. In the main, the dunes on the
+coast of the German Sea, notwithstanding the great quantity of often
+fertile land they cover, and the evils which result from their
+movement, are, upon the whole, a protective and beneficial agent, and
+their maintenance is an object of solicitude with the governments and
+people of the shores they protect.[445]
+
+
+_Use of Dunes as a Barrier against the Sea._
+
+Although the sea throws up large quantities of sand on flat lee-shores,
+there are, as we have seen, many cases where it continually encroaches
+on those same shores and washes them away. At all points of the shallow
+North Sea where the agitation of the waves extends to the bottom, banks
+are forming and rolling eastward. Hence the sea sand tends to accumulate
+upon the coast of Schleswig-Holstein and Jutland, and were there no
+conflicting influences, the shore would rapidly extend itself westward.
+But the same waves which wash the sand to the coast undermine the beach
+they cover, and still more rapidly degrade the shore at points where it
+is too high to receive partial protection by the formation of dunes upon
+it. The earth of the coast is generally composed of particles finer,
+lighter, and more transportable by water than the sea sand. While,
+therefore, the billows raised by a heavy west wind may roll up and
+deposit along the beach thousands of tons of sand, the same waves may
+swallow up even a larger quantity of fine shore earth. This earth, with
+a portion of the sand, is swept off by northwardly and southwardly
+currents, and let fall at other points of the coast, or carried off,
+altogether, out of the reach of causes which might bring it back to its
+former position.
+
+Although, then, the eastern shore of the German Ocean here and there
+advances into the sea, it in general retreats before it, and but for the
+protection afforded it by natural arrangements seconded by the art and
+industry of man, whole provinces would soon be engulfed by the waters.
+This protection consists in an almost unbroken chain of sand banks and
+dunes, extending from the northernmost point of Jutland to the Elbe, a
+distance of not much less than three hundred miles, and from the Elbe
+again, though with more frequent and wider interruptions, to the
+Atlantic borders of France and Spain.[446] So long as the dunes are
+maintained by nature or by human art, they serve, like any other
+embankment or dike, as a partial or a complete protection against the
+encroachments of the sea; and on the other hand, when their drifts are
+not checked by natural processes, or by the industry of man, they become
+a cause of as certain, if not of as sudden, destruction as the ocean
+itself whose advance they retard.
+
+
+_Encroachments of the Sea._
+
+The eastward progress of the sea on the Danish and Netherlandish coast,
+and on certain shores of the Atlantic, depends so much on local
+geological structure, on the force and direction of tidal and other
+marine currents, on the volume and rapidity of coast rivers, on the
+contingencies of the weather and on other varying circumstances, that no
+general rate can he assigned to it.
+
+At Agger, near the western end of the Liimfjord, in Jutland, the coast
+was washed away, between the years 1815 and 1839, at the rate of more
+than eighteen feet a year. The advance of the sea appears to have been
+something less rapid for a century before; but from 1840 to 1857, it
+gained upon the land no less than thirty feet a year. At other points of
+the shore of Jutland, the loss is smaller, but the sea is encroaching
+generally upon the whole line of the coast.[447]
+
+
+_The Liimfjord._
+
+The irruption of the sea into the fresh-water lagoon of Liimfjord in
+Jutland, in 1825--one of the most remarkable encroachments of the ocean
+in modern times--is expressly ascribed to "mismanagement of the dunes"
+on the narrow neck of land which separated the fjord from the North Sea.
+At earlier periods, the sea had swept across the isthmus, and even burst
+through it, but the channel had been filled up again, sometimes by
+artificial means, sometimes by the operation of natural causes, and on
+all these occasions effects were produced very similar to those
+resulting from the formation of the new channel in 1825, which still
+remains open.[448] Within comparatively recent historical ages, the
+Liimfjord has thus been several times alternately filled with fresh and
+with salt water, and man has produced, by neglecting the dunes, or at
+least might have prevented by maintaining them, changes identical with
+those which are usually ascribed to the action of great geological
+causes, and sometimes supposed to have required vast periods of time for
+their accomplishment.
+
+"This breach," says Forchhammer, "which converted the Liimfjord into a
+sound, and the northern part of Jutland into an island, occasioned
+remarkable changes. The first and most striking phenomenon was the
+sudden destruction of almost all the fresh-water fish previously
+inhabiting this lagoon, which was famous for its abundant fisheries.
+Millions of fresh-water fish were thrown on shore, partly dead and
+partly dying, and were carted off by the people. A few only survived,
+and still frequent the shores at the mouth of the brooks. The eel,
+however, has gradually accommodated itself to the change of
+circumstances, and is found in all parts of the fjord, while to all
+other fresh-water fish, the salt water of the ocean seems to have been
+fatal. It is more than probable that the sand washed in by the irruption
+covers, in many places, a layer of dead fish, and has thus prepared the
+way for a petrified stratum similar to those observed in so many older
+formations.
+
+"As it seems to be a law of nature that animals whose life is suddenly
+extinguished while yet in full vigor, are the most likely to be
+preserved by petrification, we find here one of the conditions favorable
+to the formation of such a petrified stratum. The bottom of the
+Liimfjord was covered with a vigorous growth of aquatic plants,
+belonging both to fresh and to salt water, especially _Zostera marina_.
+This vegetation totally disappeared after the irruption, and, in some
+instances, was buried by the sand; and here again we have a familiar
+phenomenon often observed in ancient strata--the indication of a given
+formation by a particular vegetable species--and when the strata
+deposited at the time of the breach shall be accessible by upheaval, the
+period of eruption will be marked by a stratum of _Zostera_, and
+probably by impressions of fresh-water fishes.
+
+"It is very remarkable that the _Zostera marina_, a sea plant, was
+destroyed even where no sand was deposited. This was probably in
+consequence of the sudden change from brackish to salt water. * * It is
+well established that the Liimfjord communicated with the German Ocean
+at some former period. To that era belong the deep beds of oyster shells
+and _Cardium edule_, which are still found at the bottom of the fjord.
+And now, after an interval of centuries, during which the lagoon
+contained no salt-water shell fish, it again produces great numbers of
+_Mytilus edulis_. Could we obtain a deep section of the bottom, we
+should find beds of _Ostrea edulis_ and _Cardium edule_, then a layer of
+_Zostera marina_ with fresh-water fish, and then a bed of _Mytilus
+edulis_. If, in course of time, the new channel should be closed, the
+brooks would fill the lagoon again with fresh water; fresh-water fish
+and shell fish would reappear, and thus we should have a repeated
+alternation of organic inhabitants of the sea and of the waters of the
+land.
+
+"These events have been accompanied with but a comparatively
+insignificant change of land surface, while the formations in the bed of
+this inland sea have been totally revolutionized in character."[449]
+
+
+_Coasts of Schleswig-Holstein, Holland, and France._
+
+On the islands on the coast of Schleswig-Holstein, the advance of the
+sea has been more unequivocal and more rapid. Near the beginning of the
+last century, the dunes which had protected the western coast of the
+island of Sylt began to roll to the east, and the sea followed closely
+as they retired. In 1757, the church of Rantum, a village upon that
+island, was obliged to be taken down in consequence of the advance of
+the sand hills; in 1791, these hills had passed beyond its site, the
+waves had swallowed up its foundations, and the sea gained so rapidly,
+that, fifty years later, the spot where they lay was seven hundred feet
+from the shore.[450]
+
+The most prominent geological landmark on the coast of Holland is the
+Huis te Britten, _Arx Britannica_, a fortress built by the Romans, in
+the time of Caligula, on the main land near the mouth of the Rhine. At
+the close of the seventeenth century, the sea had advanced sixteen
+hundred paces beyond it. The older Dutch annalists record, with much
+parade of numerical accuracy, frequent encroachments of the sea upon
+many parts of the Netherlandish coast. But though the general fact of an
+advance of the ocean upon the land is established beyond dispute, the
+precision of the measurements which have been given is open to question.
+Staring, however, who thinks the erosion of the coast much exaggerated
+by popular geographers, admits a loss of more than a million and a half
+acres, chiefly worthless morass;[451] and it is certain that but for the
+resistance of man, but for his erection of dikes and protection of
+dunes, there would now be left of Holland little but the name. It is, as
+has been already seen, still a debated question among geologists whether
+the coast of Holland now is, and for centuries has been, subsiding. I
+believe most investigators maintain the affirmative; and if the fact is
+so, the advance of the sea upon the land is, in part, due to this cause.
+But the rate of subsidence is at all events very small, and therefore
+the encroachments of the ocean upon the coast are mainly to be ascribed
+to the erosion and transportation of the soil by marine waves and
+currents.
+
+The sea is fast advancing at several points of the western coast of
+France, and unknown causes have given a new impulse to its ravages since
+the commencement of the present century. Between 1830 and 1842, the
+Point de Grave, on the north side of the Gironde, retreated one hundred
+and eighty metres, or about fifty feet per year; from the latter year to
+1846, the rate was increased to more than three times that quantity, and
+the loss in those four years was above six hundred feet. All the
+buildings at the extremity of the peninsula have been taken down and
+rebuilt farther landward, and the lighthouse of the Grave now occupies
+its third position. The sea attacked the base of the peninsula also, and
+the Point de Grave and the adjacent coasts have been for twenty years
+the scene of one of the most obstinately contested struggles between man
+and the ocean recorded in the annals of modern engineering.
+
+It cannot, indeed, be affirmed that human power is able to arrest
+altogether the incursions of the waves on sandy coasts, by planting the
+beach, and clothing the dunes with wood. On the contrary, both in
+Holland and on the French coast, it has been found necessary to protect
+the dunes themselves by piling and by piers and sea walls of heavy
+masonry. But experience has amply shown that the processes referred to
+are entirely successful in preventing the movement of the dunes, and the
+drifting of their sands over cultivated lands behind them; and that, at
+the same time, the plantations very much retard the landward progress of
+the waters.[452]
+
+
+_Drifting of Dune Sands._
+
+Besides their importance as a barrier against the inroads of the ocean,
+dunes are useful by sheltering the cultivated ground behind them from
+the violence of the sea wind, from salt spray, and from the drifts of
+beach sand which would otherwise overwhelm them. But the dunes
+themselves, unless their surface sands are kept moist, and confined by
+the growth of plants, or at least by a crust of vegetable earth, are
+constantly rolling inward; and thus, while, on one side, they lay bare
+the traces of ancient human habitations or other evidences of the social
+life of primitive man, they are, on the other, burying fields, houses,
+churches, and converting populous districts into barren and deserted
+wastes.
+
+Especially destructive are they when, by any accident, a cavity is
+opened into them to a considerable depth, thereby giving the wind access
+to the interior, where the sand is thus first dried, and then scooped
+out and scattered far over the neighboring soil. The dune is now a
+magazine of sand, no longer a rampart against it, and mischief from this
+source seems more difficult to resist than from almost any other drift,
+because the supply of material at the command of the wind, is more
+abundant and more concentrated than in its original thin and widespread
+deposits on the beach. The burrowing of conies in the dunes is, in this
+way, not unfrequently a cause of their destruction and of great injury
+to the fields behind them. Drifts, and even inland sand hills, sometimes
+result from breaking the surface of more level sand deposits, far within
+the range of the coast dunes. Thus we learn from Staring, that one of
+the highest inland dunes in Friesland owes its origin to the opening of
+the drift sand by the uprooting of a large oak.[453]
+
+Great as are the ravages produced by the encroachment of the sea upon
+the western shores of continental Europe, they have been in some degree
+compensated by spontaneous marine deposits at other points of the coast,
+and we have seen in a former chapter that the industry of man has
+reclaimed a large territory from the bosom of the ocean. These latter
+triumphs are not of recent origin, and the incipient victories which
+paved the way for them date back perhaps as far as ten centuries. In the
+mean time, the dunes had been left to the operation of the laws of
+nature, or rather freed, by human imprudence, from the fetters with
+which nature had bound them, and it is scarcely three generations since
+man first attempted to check their destructive movements. As they
+advanced, he unresistingly yielded and retreated before them, and they
+have buried under their sandy billows many hundreds of square miles of
+luxuriant cornfields and vineyards and forests.
+
+
+_Dunes of Gascony._
+
+On the west coast of France, a belt of dunes, varying in width from a
+quarter of a mile to five miles, extends from the Adour to the estuary
+of the Gironde, and covers an area of three hundred and seventy-five
+square miles. When not fixed by vegetable growths, they advance eastward
+at a mean rate of about one rod, or sixteen and a half feet, a year. We
+do not know historically when they began to drift, but if we suppose
+their motion to have been always the same as at present, they would have
+passed over the space between the sea coast and their eastern boundary,
+and covered the large area above mentioned, in fourteen hundred years.
+We know, from written records, that they have buried extensive fields
+and forests and thriving villages, and changed the courses of rivers,
+and that the lighter particles carried from them by the winds, even
+where not transported in sufficient quantities to form sand hills, have
+rendered sterile much land formerly fertile.[454] They have also
+injuriously obstructed the natural drainage of the maritime districts by
+choking up the beds of the streams, and forming lakes and pestilential
+swamps of no inconsiderable extent. In fact, so completely do they
+embank the coast, that between the Gironde and the village of Mimizan, a
+distance of one hundred miles, there are but two outlets for the
+discharge of all the waters which flow from the land to the sea; and the
+eastern front of the dunes is bordered by a succession of stagnant
+pools, some of which are more than six miles in length and breadth.[455]
+
+
+_The Dunes of Denmark and Prussia._
+
+In the small kingdom of Denmark, inclusive of the duchies of Schleswig
+and Holstein, the dunes cover an area of more than two hundred and sixty
+square miles. The breadth of the chain is very various, and in some
+places it consists only of a single row of sand hills, while in others,
+it is more than six miles wide. The general rate of eastward movement of
+the drifting dunes is from three to twenty-four feet per annum. If we
+adopt the mean of thirteen feet and a half for the annual motion, the
+dunes have traversed the widest part of the belt in about twenty-five
+hundred years. Historical data are wanting as to the period of the
+formation of these dunes and of the commencement of their drifting; but
+there is recorded evidence that they have buried a vast extent of
+valuable land within three or four centuries, and further proof is found
+in the fact that the movement of the sands is constantly uncovering
+ruins of ancient buildings, and other evidences of human occupation, at
+points far within the present limits of the uninhabitable desert.
+Andresen estimates the average depth of the sand deposited over this
+area at thirty feet, which would give a cubic mile and a half for the
+total quantity.[456]
+
+The drifting of the dunes on the coast of Prussia commenced not much
+more than a hundred years ago. The Frische Nehrung is separated from the
+mainland by the Frische Haff, and there is but a narrow strip of arable
+land along its eastern borders. Hence its rolling sands have covered a
+comparatively small extent of dry land, but fields and villages have
+been buried and valuable forests laid waste by them. The loose coast row
+has drifted over the inland ranges, which, as was noticed in the
+description of these dunes on a former page, were protected by a surface
+of different composition, and the sand has thus been raised to a height
+which it could not have reached upon level ground. This elevation has
+enabled it to advance upon and overwhelm woods, which, upon a plain,
+would have checked its progress, and, in one instance, a forest of many
+hundred acres of tall pines was destroyed by the drifts between 1804 and
+1827.
+
+
+_Control of Dunes by Man._
+
+There are three principal modes in which the industry of man is brought
+to bear upon the dunes. First, the creation of them, at points where,
+from changes in the currents or other causes, new encroachments of the
+sea are threatened; second, the maintenance and protection of them where
+they have been naturally formed; and third, the removal of the inner
+rows where the belt is so broad that no danger is to be apprehended from
+the loss of them.
+
+
+_Artificial Formation of Dunes._
+
+In describing the natural formation of dunes, it was said that they
+began with an accumulation of sand around some vegetable or other
+accidental obstruction to the drifting of the particles. A high,
+perpendicular cliff, which deadens the wind altogether, prevents all
+accumulation of sand; but, up to a certain point, the higher and broader
+the obstruction, the more sand will heap up in front of it, and the more
+will that which falls behind it be protected from drifting farther. This
+familiar observation has taught the inhabitants of the coast that an
+artificial wall or dike will, in many situations, give rise to a broad
+belt of dunes. Thus a sand dike or wall, of three or four miles in
+length, thrown in 1610 across the Koegras, a tide-washed flat between
+the Zuiderzee and the North Sea, has occasioned the formation of rows of
+dunes a mile in breadth, and thus excluded the sea altogether from the
+Koegras. A similar dike, called the Zijperzeedijk, has produced another
+scarcely less extensive belt in the course of two centuries.
+
+A few years since, the sea was threatening to cut through the island of
+Ameland, and, by encroachment on the southern side and the blowing off
+of the sand from a low flat which connected the two higher parts of the
+island, it had made such progress, that in heavy storms the waves
+sometimes rolled quite across the isthmus. The construction of a
+breakwater and a sand dike have already checked the advance of the sea,
+and a large number of sand hills has been formed, the rapid growth of
+which promises complete future security against both wind and wave.
+Similar effects have been produced by the erection of plank fences, and
+even of simple screens of wattling and reeds.[457]
+
+
+_Protection of Dunes._
+
+The dunes of Holland are sometimes protected from the dashing of the
+waves by a _revetement_ of stone, or by piles; and the lateral
+high-water currents, which wash away their base, are occasionally
+checked by transverse walls running from the foot of the dunes to
+low-water mark; but the great expense of such constructions has
+prevented their adoption on a large scale.[458] The principal means
+relied on for the protection of the sand hills are the planting of their
+surfaces and the exclusion of burrowing and grazing animals. There are
+grasses, creeping plants, and shrubs of spontaneous growth, which
+flourish in loose sand, and, if protected, spread over considerable
+tracts, and finally convert their face into a soil capable of
+cultivation, or, at least, of producing forest trees. Krause enumerates
+one hundred and seventy-one plants as native to the coast sands of
+Prussia, and the observations of Andresen in Jutland carry the number of
+these vegetables up to two hundred and thirty-four.
+
+Some of these plants, especially the _Arundo arenaria_ or _arenosa_, or
+_Psamma_ or _Psammophila arenaria_--Klittetag, or Hjelme in Danish, helm
+in Dutch, Duenenhalm, Sandschilf, or Huegelrohr in German, gourbet in
+French, and marram in English--are exclusively confined to sandy soils,
+and thrive well only in a saline atmosphere.[459] The arundo grows to
+the height of about twenty-four inches, but sends its strong roots with
+their many rootlets to a distance of forty or fifty feet. It has the
+peculiar property of nourishing best in the loosest soil, and a sand
+shower seems to refresh it as the rain revives the thirsty plants of the
+common earth. Its roots bind together the dunes, and its leaves protect
+their surface. When the sand ceases to drift, the arundo dies, its
+decaying roots fertilizing the sand, and the decomposition of its leaves
+forming a layer of vegetable earth over it. Then follows a succession of
+other plants which gradually fit the sand hills, by growth and decay,
+for forest planting, for pasturage, and sometimes for ordinary
+agricultural use.
+
+But the protection and gradual transformation of the dunes is not the
+only service rendered by this valuable plant. Its leaves are nutritious
+food for sheep and cattle, its seeds for poultry;[460] cordage and
+netting twine are manufactured from its fibres, it makes a good material
+for thatching, and its dried roots furnish excellent fuel. These useful
+qualities, unfortunately, are too often prejudicial to its growth. The
+peasants feed it down with their cattle, cut it for rope making, or dig
+it up for fuel, and it has been found necessary to resort to severe
+legislation to prevent them from bringing ruin upon themselves by thus
+improvidently sacrificing their most effectual safeguard against the
+drifting of the sands.[461]
+
+In 1539, a decree of Christian III, king of Denmark, imposed a fine upon
+persons convicted of destroying certain species of sand plants upon the
+west coast of Jutland. This ordinance was renewed and made more
+comprehensive in 1558, and in 1569 the inhabitants of several districts
+were required, by royal rescript, to do their best to check the sand
+drifts, though the specific measures to be adopted for that purpose are
+not indicated. Various laws against stripping the dunes of their
+vegetation were enacted in the following century, but no active measures
+were taken for the subjugation of the sand drifts until 1779, when a
+preliminary system of operation for that purpose was adopted. This
+consisted in little more than the planting of the _Arundo arenaria_ and
+other sand plants, and the exclusion of animals destructive to these
+vegetables.[462] Ten years later, plantations of forest trees, which
+have since proved so valuable a means of fixing the dunes and rendering
+them productive, were commenced, and have been continued ever
+since.[463] During this latter period, Bremontier, without any knowledge
+of what was doing in Denmark, experimented upon the cultivation of
+forest trees on the dunes of Gascony, and perfected a system, which,
+with some improvements in matters of detail, is still largely pursued
+on those shores. The example of Denmark was soon followed in the
+neighboring kingdom of Prussia, and in the Netherlands; and, as we shall
+see hereafter, these improvements have been everywhere crowned with most
+flattering success.
+
+Under the administration of Reventlov, a little before the close of the
+last century, the Danish Government organized a regular system of
+improvement in the economy of the dunes. They were planted with the
+arundo and other vegetables of similar habits, protected against
+trespassers, and at last partly covered with forest trees. By these
+means much waste soil has been converted into arable ground, a large
+growth of valuable timber obtained, and the further spread of the
+drifts, which threatened to lay waste the whole peninsula of Jutland, to
+a considerable extent arrested.
+
+In France, the operations for fixing and reclaiming the dunes--which
+began under the direction of Bremontier about the same time as in
+Denmark, and which are, in principle and in many of their details,
+similar to those employed in the latter kingdom--have been conducted on
+a far larger scale, and with greater success, than in any other country.
+This is partly owing to a climate more favorable to the growth of
+suitable forest trees than that of Northern Europe, and partly to the
+liberality of the Government, which, having more important landed
+interests to protect, has put larger means at the disposal of the
+engineers than Denmark and Prussia have found it convenient to
+appropriate to that purpose. The area of the dunes already secured from
+drifting, and planted by the processes invented by Bremontier and
+perfected by his successors, is about 100,000 acres.[464] This amount of
+productive soil, then, has been added to the resources of France, and a
+still greater quantity of valuable land has been thereby rescued from
+the otherwise certain destruction with which it was threatened by the
+advance of the rolling sand hills.
+
+The improvements of the dunes on the coast of West Prussia began in
+1795, under Soeren Bjoern, a native of Denmark, and, with the exception of
+the ten years between 1807 and 1817, they have been prosecuted ever
+since. The methods do not differ essentially from those employed in
+Denmark and France, though they are modified by local circumstances,
+and, with respect to the trees selected for planting, by climate. In
+1850, between the mouth of the Vistula and Kahlberg, 6,300 acres,
+including about 1,900 acres planted with pines and birches, had been
+secured from drifting; between Kahlberg and the eastern boundary of
+West-Prussia, 8,000 acres; and important preliminary operations had been
+carried on for subduing the dunes on the west coast.[465]
+
+
+_Trees suited to Dune Plantations._
+
+The tree which has been found to thrive best upon the sand hills of the
+French coast, and at the same time to confine the sand most firmly and
+yield the largest pecuniary returns, is the maritime pine, _Pinus
+maritima_, a species valuable both for its timber and for its resinous
+products. It is always grown from seed, and the young shoots require to
+be protected for several seasons, by the branches of other trees,
+planted in rows, or spread over the surface and staked down, by the
+growth of the _Arundo arenaria_ and other small sand plants, or by
+wattled hedges. The beach, from which the sand is derived, has been
+generally planted with the arundo, because the pine does not thrive well
+so near the sea; but it is thought that a species of tamarisk is likely
+to succeed in that latitude even better than the arundo. The shade and
+the protection offered by the branching top of this pine are favorable
+to the growth of deciduous trees, and, while still young, of shrubs and
+smaller plants, which contribute more rapidly to the formation of
+vegetable mould, and thus, when the pine has once taken root, the
+redemption of the waste is considered as effectually secured.
+
+In France, the maritime pine is planted on the sands of the interior as
+well as on the dunes of the sea coast, and with equal advantage. This
+tree resembles the pitch pine of the Southern American States in its
+habits, and is applied to the same uses. The extraction of turpentine
+from it begins at the age of about twenty years, or when it has attained
+a diameter of from nine to twelve inches. Incisions are made up and down
+the trunk, to the depth of about half an inch in the wood, and it is
+insisted that if not more than two such slits are cut, the tree is not
+sensibly injured by the process. The growth, indeed, is somewhat
+checked, but the wood becomes superior to that of trees from which the
+turpentine is not extracted. Thus treated, the pine continues to
+flourish to the age of one hundred or one hundred and twenty years, and
+up to this age the trees on a hectare yield annually 350 kilogrammes of
+essence of turpentine, and 280 kilogrammes of resin, worth together 110
+francs. The expense of extraction and distillation is calculated at 44
+francs, and a clear profit of 66 francs per hectare, or more than five
+dollars per acre, is left.[466] This is exclusive of the value of the
+timber, when finally cut, which, of course, amounts to a very
+considerable sum.
+
+In Denmark, where the climate is much colder, hardier conifers, as well
+as the birch and other northern trees, are found to answer a better
+purpose than the maritime pine, and it is doubtful whether this tree
+would be able to resist the winter on the dunes of Massachusetts.
+Probably the pitch pine of the Northern States, in conjunction with some
+of the American oaks, birches, and poplars, and especially the robinia
+or locust, would prove very suitable to be employed on the sand hills of
+Cape Cod and Long Island. The ailanthus, now coming into notice as a
+sand-loving tree, may, perhaps, serve a better purpose than any of them.
+
+
+_Extent of Dunes in Europe._
+
+The dunes of Denmark, as we have seen, cover an area of two hundred and
+sixty square miles, or one hundred and sixty-six thousand acres; those
+of the Prussian coast are vaguely estimated at from eighty-five to one
+hundred and ten thousand acres; those of Holland at one hundred and
+forty thousand acres;[467] those of Gascony at about three hundred
+thousand acres.[468] I do not find any estimate of their extent in other
+provinces of France, in the duchies of Schleswig and Holstein, or in the
+Baltic provinces of Russia, but it is probable that the entire quantity
+of dune land upon the eastern shores of the Atlantic and the Baltic does
+not fall much short of a million of acres.[469] This vast deposit of sea
+sand extends along the coast for a distance of several hundred miles,
+and from the time of the destruction of the forests which covered it, to
+the year 1789, the whole line was rolling inward and burying the soil
+beneath it, or rendering the fields unproductive by the sand which
+drifted from it. At the same time, as the sand hills moved eastward, the
+ocean was closely following their retreat and swallowing up the ground
+they had covered, as fast as their movement left it bare.
+
+Planting the dunes has completely prevented the surface sands from
+blowing over the soil to the leeward of the plantations, and though it
+has not, in all cases, arrested the encroachments of the sea, it has so
+greatly retarded the rapidity of their advance, that sandy coasts, when
+once covered with forests, may be considered as substantially secure, so
+long as proper measures are taken for the protection of the woods.
+
+
+_Dune Vineyards of Cap Breton._
+
+In the vicinity of Cap Breton in France, a peculiar process is
+successfully employed, both for preventing the drifting of dunes, and
+for rendering the sands themselves immediately productive; but this
+method is applicable only in exceptional cases of favorable climate and
+exposure. It consists in planting vineyards upon the dunes, and
+protecting them by hedges of broom, _Erica scoparia_, so disposed as to
+form rectangles about thirty feet by forty. The vines planted in these
+enclosures thrive admirably, and the grapes produced by them are among
+the best grown in France. The dunes are so far from being an unfavorable
+soil for the vine, that fresh sea-sand is regularly employed as a
+fertilizer for it, alternating every other season with ordinary manure.
+The quantity of sand thus applied every second year, raises the surface
+of the vineyard about four or five inches. The vines are cut down every
+year to three or four shoots, and the raising of the soil rapidly
+covers the old stocks. As fast as buried, they send out new roots near
+the surface, and thus the vineyard is constantly renewed, and has always
+a youthful appearance, though it may have been already planted a couple
+of generations. This practice is ascertained to have been followed for
+two centuries, and is among the oldest well-authenticated attempts of
+man to resist and vanquish the dunes.[470]
+
+
+_Removal of Dunes._
+
+The artificial removal of dunes, no longer necessary as a protection,
+does not appear to have been practised upon a large scale except in the
+Netherlands, where the numerous canals furnish an easy and economical
+means of transporting the sand, and where the construction and
+maintenance of sea and river dikes, and of causeways and other
+embankments and fillings, create a great demand for that material. Sand
+is also employed in Holland, in large quantities, for improving the
+consistence of the tough clay bordering upon or underlying diluvial
+deposits, and for forming an artificial soil for the growth of certain
+garden and ornamental vegetables. When the dunes are removed, the ground
+they covered is restored to the domain of industry; and the quantity of
+land, recovered in the Netherlands by the removal of the barren sands
+which encumbered it, amounts to hundreds and perhaps thousands of
+acres.[471]
+
+
+_Inland Sand Plains._
+
+The inland sand plains of Europe are either derived from the drifting of
+dunes or other beach sands, or consist of diluvial deposits. As we have
+seen, when once the interior of a dune is laid open to the wind, its
+contents are soon scattered far and wide over the adjacent country, and
+the beach sands, no longer checked by the rampart which nature had
+constrained them to build against their own encroachments, are also
+carried to considerable distances from the coast. Few regions have
+suffered so much from this cause in proportion to their extent, as the
+peninsula of Jutland. So long as the woods, with which nature had
+planted the Danish dunes, were spared, they seem to have been
+stationary, and we have no historical evidence, of an earlier date than
+the sixteenth century, that they had become in any way injurious. From
+that period, there are frequent notices of the invasions of cultivated
+grounds by the sands; and excavations are constantly bringing to light
+proof of human habitation and of agricultural industry, in former ages,
+on soils now buried beneath deep drifts from the dunes and beaches of
+the sea coast.[472]
+
+Extensive tracts of valuable plain land in the Netherlands and in France
+have been covered in the same way with a layer of sand deep enough to
+render them infertile, and they can be restored to cultivation only by
+processes analogous to those employed for fixing and improving the
+dunes.[473] Diluvial sand plains, also, have been reclaimed by these
+methods in the Duchy of Austria, between Vienna and the Semmering ridge,
+in Jutland, and in the great champaign country of Northern Germany,
+especially the Mark Brandenburg, where artificial forests can be
+propagated with great ease, and where, consequently, this branch of
+industry has been pursued on a great scale, and with highly beneficial
+results, both as respects the supply of forest products and the
+preparation of the soil for agricultural use.
+
+As a general rule, inland sands are looser, dryer, and more inclined to
+drift, than those of the sea coast, where the moist and saline
+atmosphere of the ocean keeps them always more or less humid and
+cohesive. No shore dunes are so movable as the medanos of Peru described
+in a passage quoted from Poeppig on a former page, or as the sand hills
+of Poland, both of which seem better entitled to the appellation of sand
+waves than those of the Sahara or of the Arabian desert. The sands of
+the valley of the Lower Euphrates--themselves probably of submarine
+origin, and not derived from dunes--are advancing to the northwest with
+a rapidity which seems fabulous when compared with the slow movement of
+the sand hills of Gascony and the Low German coasts. Loftus, speaking of
+Niliyya, an old Arab town a few miles east of the ruins of Babylon, says
+that, "in 1848, the sand began to accumulate around it, and in six
+years, the desert, within a radius of six miles, was covered with
+little, undulating domes, while the ruins of the city were so buried
+that it is now impossible to trace their original form or extent."[474]
+Loftus considers this sand flood as the "vanguard of those vast drifts
+which, advancing from the southeast, threaten eventually to overwhelm
+Babylon and Baghdad."
+
+An observation of Layard, cited by Loftus, appears to me to furnish a
+possible explanation of this irruption. He "passed two or three places
+where the sand, issuing from the earth like water, is called
+'Aioun-er-rummal,' sand springs." These "springs" are very probably
+merely the drifting of sand from the ancient subsoil, where the
+protecting crust of aquatic deposit and vegetable earth has been broken
+through, as in the case of the drift which arose from the upturning of
+an oak mentioned on a former page. When the valley of the Euphrates was
+regularly irrigated and cultivated, the underlying sands were bound by
+moisture, alluvial slime, and vegetation; but now, that all improvement
+is neglected, and the surface, no longer watered, has become parched,
+powdery, and naked, a mere accidental fissure in the superficial stratum
+may soon be enlarged to a wide opening, that will let loose sand enough
+to overwhelm a province.
+
+
+_The Landes of Gascony._
+
+The most remarkable sand plain of France lies at the southwestern
+extremity of the empire, and is generally known as the Landes, or
+heaths, of Gascony. Clave thus describes it: "Composed of pure sand,
+resting on an impermeable stratum called _alios_, the soil of the Landes
+was, for centuries, considered incapable of cultivation. Parched in
+summer, drowned in winter, it produced only ferns, rushes, and heath,
+and scarcely furnished pasturage for a few half-starved flocks. To crown
+its miseries, this plain was continually threatened by the encroachments
+of the dunes. Vast ridges of sand, thrown up by the waves, for a
+distance of more than fifty leagues along the coast, and continually
+renewed, were driven inland by the west wind, and, as they rolled over
+the plain, they buried the soil and the hamlets, overcame all
+resistance, and advanced with fearful regularity. The whole province
+seemed devoted to certain destruction, when Bremontier invented his
+method of fixing the dunes by plantations of the maritime pine."[475]
+
+Although the Landes had been almost abandoned for ages, they show
+numerous traces of ancient cultivation and prosperity, and it is
+principally by means of the encroachments of the sands that they have
+become reduced to their present desolate condition. The destruction of
+the coast towns and harbors, which furnished markets for the products of
+the plains, the damming up of the rivers, and the obstruction of the
+smaller channels of natural drainage by the advance of the dunes, were
+no doubt very influential causes; and if we add the drifting of the sea
+sand over the soil, we have at least a partial explanation of the
+decayed agriculture and diminished population of this great waste. When
+the dunes were once arrested, and the soil to the east of them was felt
+to be secure against invasion by them, experiments, in the way of
+agricultural improvement, by drainage and plantation, were commenced,
+and they have been attended with such signal success, that the complete
+recovery of one of the dreariest and most extensive wastes in Europe may
+be considered as both a probable and a near event.[476]
+
+
+_The Belgian Campine._
+
+In the northern part of Belgium, and extending across the confines of
+Holland, is another very similar heath plain, called the Campine. This
+is a vast sand flat, interspersed with marshes and inland dunes, and,
+until recently, considered wholly incapable of cultivation. Enormous
+sums have been expended in reclaiming it by draining and other familiar
+agricultural processes, but without results at all proportional to the
+capital invested. In 1849, the unimproved portion of the Campine was
+estimated at little less than three hundred and fifty thousand acres.
+The example of France has prompted experiments in the planting of trees,
+especially the maritime pine, upon this barren waste, and the results
+have been such as to show that its sands may both be fixed and made
+productive, not only without loss, but with positive pecuniary
+advantage.[477]
+
+
+_Sands and Steppes of Eastern Europe._
+
+There are still unsubdued sand wastes in many parts of interior Europe
+not familiarly known to tourists or even geographers. "Olkuez and
+Schiewier in Poland," says Naumann, "lie in true sand deserts, and a
+boundless plain of sand stretches around Ozenstockau, on which there
+grows neither tree nor shrub. In heavy winds, this plain resembles a
+rolling sea, and the sand hills rise and disappear like the waves of the
+ocean. The heaps of waste from the Olkuez mines are covered with sand to
+the depth of four fathoms."[478] No attempts have yet been made to
+subdue the sands of Poland, but when peace and prosperity shall be
+restored to that unhappy country, there is no reasonable doubt that the
+measures, which have proved so successful on similar formations in
+Germany, may be employed with advantage in the Polish deserts.
+
+There are sand drifts in parts of the steppes of Russia, but in general
+the soil of those vast plains is of a different, though very varied,
+composition, and is covered with vegetation. The steppes, however, have
+many points of analogy with the sand plains of Northern Germany, and if
+they are ever fitted for civilized occupation, it must be by the same
+means, that is, by planting forests. It is disputed whether the steppes
+were ever wooded. They were certainly bare of forest growth at a very
+remote period; for Herodotus describes the country of the Scythians
+between the Ister and the Tanais as woodless, with the exception of the
+small province of Xylaea between the Dnieper and the Gulf of Perekop.
+They are known to have been occupied by a large nomade and pastoral
+population down to the sixteenth century, though these tribes are now
+much reduced in numbers. The habits of such races are scarcely less
+destructive to the forest than those of civilized life. Pastoral tribes
+do not employ much wood for fuel or for construction, but they
+carelessly or recklessly burn down the forests, and their cattle
+effectually check the growth of young trees wherever their range
+extends.
+
+At present, the furious winds which sweep over the plains, the droughts
+of summer, and the rights and abuses of pasturage, constitute very
+formidable obstacles to the employment of measures which have been
+attended with so valuable results on the sand wastes of France and
+Germany. The Russian Government has, however, attempted the wooding of
+the steppes, and there are thriving plantations in the neighborhood of
+Odessa, where the soil is of a particularly loose and sandy
+character.[479] The trees best suited to this locality, and, as there is
+good reason to suppose, to sand plains in general, is the _Ailanthus
+glandulosa_, or Japan varnish tree.[480] The remarkable success which
+has crowned the experiments with the ailanthus at Odessa, will, no
+doubt, stimulate to similar trials elsewhere, and it seems not
+improbable that the arundo and the maritime pine, which have fixed so
+many thousand acres of drifting sands in Western Europe, will be,
+partially at least, superseded by the tamarisk and the varnish tree.
+
+
+_Advantages of Reclaiming the Sands._
+
+If we consider the quantity of waste land which has been made productive
+by the planting of the sand hills and plains, and the extent of fertile
+soil, the number of villages and other human improvements, and the value
+of the harbors, which the same process has saved from being buried under
+the rolling dunes, and at last swallowed up forever by the invasions of
+the sea, we shall be inclined to rank Bremontier and Reventlov among the
+greatest benefactors of their race. With the exception of the dikes of
+the Netherlands, their labors are the first deliberate and direct
+attempts of man to make himself, on a great scale, a geographical power,
+to restore natural balances which earlier generations had disturbed, and
+to atone, by acts guided by foreseeing and settled purpose, for the
+waste which thoughtless improvidence had created.
+
+
+_Government Works._
+
+There is an important political difference between these latter works
+and the diking system of the Netherlandish and German coasts. The dikes
+originally were, and in modern times very generally have been, private
+enterprises, undertaken with no other aim than to add a certain quantity
+of cultivable soil to the former possessions of their proprietor, or
+sometimes of the state. In short, with few exceptions, they have been
+merely a pecuniary investment, a mode of acquiring land not economically
+different from purchase. The planting of the dunes, on the contrary, has
+always been a public work, executed, not with the expectation of reaping
+a regular direct percentage of income from the expenditure, but dictated
+by higher views of state economy--by the same governmental principles,
+in fact, which animate all commonwealths in repelling invasion by
+hostile armies, or in repairing the damages that invading forces may
+have inflicted on the general interests of the people. The restoration
+of the forests in the southern part of France, as now conducted by the
+Government of that empire, is a measure of the same elevated character
+as the fixing of the dunes. In former ages, forests were formed or
+protected simply for the sake of the shelter they afforded to game, or
+for the timber they yielded; but the recent legislation of France, and
+of some other Continental countries, on this subject, looks to more
+distant as well as nobler ends, and these are among the public acts
+which most strongly encourage the hope that the rulers of Christendom
+are coming better to understand the true duties and interests of
+civilized government.
+
+
+
+
+CHAPTER VI.
+
+PROJECTED OR POSSIBLE GEOGRAPHICAL CHANGES BY MAN.
+
+CUTTING OF MARINE ISTHMUSES--THE SUEZ CANAL--CANAL ACROSS ISTHMUS OF
+DARIEN--CANALS TO THE DEAD SEA--MARITIME CANALS IN GREECE--CANAL OF
+SAROS--CAPE COD CANAL--DIVERSION OF THE NILE--CHANGES IN THE CASPIAN--
+IMPROVEMENTS IN NORTH AMERICAN HYDROGRAPHY--DIVERSION OF RHINE--
+DRAINING OF THE ZUIDERZEE--WATERS OF THE KARST--SUBTERRANEAN WATERS
+OF GREECE--SOIL BELOW ROCK--COVERING ROCKS WITH EARTH--WADIES OF ARABIA
+PETRAEA--INCIDENTAL EFFECTS OF HUMAN ACTION--RESISTANCE TO GREAT NATURAL
+FORCES--EFFECTS OF MINING--ESPY'S THEORIES--RIVER SEDIMENT--NOTHING
+SMALL IN NATURE.
+
+
+_Cutting of Marine Isthmuses._
+
+Besides the great enterprises of physical transformation of which I have
+already spoken, other works of internal improvement or change have been
+projected in ancient and modern times, the execution of which would
+produce considerable, and, in some cases, extremely important,
+revolutions in the face of the earth. Some of the schemes to which I
+refer are evidently chimerical; others are difficult, indeed, but cannot
+be said to be impracticable, though discouraged by the apprehension of
+disastrous consequences from the disturbance of existing natural or
+artificial arrangements; and there are still others, the accomplishment
+of which is ultimately certain, though for the present forbidden by
+economical considerations.
+
+When we consider the number of narrow necks or isthmuses which separate
+gulfs and bays of the sea from each other, or from the main ocean, and
+take into account the time and cost, and risks of navigation which
+would be saved by executing channels to connect such waters, and thus
+avoiding the necessity of doubling long capes and promontories, or even
+continents, it seems strange that more of the enterprise and money which
+have been so lavishly expended in forming artificial rivers for internal
+navigation should not have been bestowed upon the construction of
+maritime canals. Many such have been projected in early and in recent
+ages, and some trifling cuts between marine waters have been actually
+made, but no work of this sort, possessing real geographical or even
+commercial importance, has yet been effected.
+
+These enterprises are attended with difficulties and open to objections,
+which are not, at first sight, obvious. Nature guards well the chains by
+which she connects promontories with mainlands, and binds continents
+together. Isthmuses are usually composed of adamantine rock or of
+shifting sands--the latter being much the more refractory material to
+deal with. In all such works there is a necessity for deep excavation
+below low-water mark--always a matter of great difficulty; the
+dimensions of channels for sea-going ships must be much greater than
+those of canals of inland navigation; the height of the masts or smoke
+pipes of that class of vessels would often render bridging impossible,
+and thus a ship canal might obstruct a communication more important than
+that which it was intended to promote; the securing of the entrances of
+marine canals and the construction of ports at their termini would in
+general be difficult and expensive, and the harbors and the channel
+which connected them would be extremely liable to fill up by deposits
+washed in from sea and shore. Besides all this, there is, in many cases,
+an alarming uncertainty as to the effects of joining together waters
+which nature has put asunder. A new channel may deflect strong currents
+from safe courses, and thus occasion destructive erosion of shores
+otherwise secure, or promote the transportation of sand or slime to
+block up important harbors, or it may furnish a powerful enemy with
+dangerous facilities for hostile operations along the coast.
+
+Nature sometimes mocks the cunning and the power of man by spontaneously
+performing, for his benefit, works which he shrinks from undertaking,
+and the execution of which by him she would resist with unconquerable
+obstinacy. A dangerous sand bank, that all the enginery of the world
+could not dredge out in a generation, may be carried off in a night by a
+strong river flood, or a current impelled by a violent wind from an
+unusual quarter, and a passage scarcely navigable by fishing boats may
+be thus converted into a commodious channel for the largest ship that
+floats upon the ocean. In the remarkable gulf of Liimfjord in Jutland,
+nature has given a singular example of a canal which she alternately
+opens as a marine strait, and, by shutting again, converts into a
+fresh-water lagoon. The Liimfjord was doubtless originally an open
+channel from the Atlantic to the Baltic between two islands, but the
+sand washed up by the sea blocked up the western entrance, and built a
+wall of dunes to close it more firmly. This natural dike, as we have
+seen, has been more than once broken through, and it is perhaps in the
+power of man, either permanently to maintain the barrier, or to remove
+it and keep a navigable channel constantly open. If the Liimfjord
+becomes an open strait, the washing of sea sand through it would perhaps
+block up some of the belts and small channels now important for the
+navigation of the Baltic, and the direct introduction of a tidal current
+might produce very perceptible effects on the hydrography of the
+Cattegat.
+
+
+_The Suez Canal._
+
+If the Suez Canal--the greatest and most truly cosmopolite physical
+improvement ever undertaken by man--shall prove successful, it will
+considerably affect the basins of the Mediterranean and of the Red Sea,
+though in a different manner, and probably in a less degree than the
+diversion of the current of the Nile from the one to the other--to which
+I shall presently refer--would do. It is, indeed, conceivable, that if a
+free channel be once cut from sea to sea, the coincidence of a high tide
+and a heavy south wind might produce a hydraulic force that would
+convert the narrow canal into an open strait. In such a case, it is
+impossible to estimate, or even to foresee, the consequences which might
+result from the unobstructed mingling of the flowing and ebbing currents
+of the Red Sea with the almost tideless waters of the Mediterranean.
+There can be no doubt, however, that they would be of a most important
+character as respects the simply geographical features and the organic
+life of both. But the shallowness of the two seas at the termini of the
+canal, the action of the tides of the one and the currents of the other,
+and the nature of the intervening isthmus, render the occurrence of such
+a cataclysm in the highest degree improbable. The obstruction of the
+canal by sea sand at both ends is a danger far more difficult to guard
+against and avert, than an irruption of the waters of either sea.
+
+There is, then, no reason to expect any change of coast lines or of
+natural navigable channels as a direct consequence of the opening of the
+Suez Canal, but it will, no doubt, produce very interesting revolutions
+in the animal and vegetable population of both basins. The
+Mediterranean, with some local exceptions--such as the bays of
+Calabria, and the coast of Sicily so picturesquely described by
+Quatrefages[481]--is comparatively poor in marine vegetation, and in
+shell as well as in fin fish. The scarcity of fish in some of its gulfs
+is proverbial, and you may scrutinize long stretches of beach on its
+northern shores, after every south wind for a whole winter, without
+finding a dozen shells to reward your search. But no one who has not
+looked down into tropical or subtropical seas can conceive the amazing
+wealth of the Red Sea in organic life. Its bottom is carpeted or paved
+with marine plants, with zoophytes and with shells, while its waters are
+teeming with infinitely varied forms of moving life. Most of its
+vegetables and its animals, no doubt, are confined by the laws of their
+organization to warmer temperatures than that of the Mediterranean, but
+among them there must be many, whose habitat is of a wider range, many
+whose powers of accommodation would enable them to acclimate themselves
+in a colder sea.
+
+We may suppose the less numerous aquatic fauna and flora of the
+Mediterranean to be equally capable of climatic adaptation, and hence,
+when the canal shall be opened, there will be an interchange of the
+organic population not already common to both seas. Destructive species,
+thus newly introduced, may diminish the numbers of their proper prey in
+either basin, and, on the other hand, the increased supply of
+appropriate food may greatly multiply the abundance of others, and at
+the same time add important contributions to the aliment of man in the
+countries bordering on the Mediterranean.
+
+A collateral feature of this great project deserves notice as possessing
+no inconsiderable geographical importance. I refer to the conduit or
+conduits constructed from the Nile to the isthmus, primarily to supply
+fresh water to the laborers on the great canal, and ultimately to serve
+as aqueducts for the city of Suez, and for the irrigation and
+reclamation of a large extent of desert soil. In the flourishing days of
+the Egyptian empire, the waters of the Nile were carried over important
+districts east of the river. In later ages, most of this territory
+relapsed into a desert, from the decay of the canals which once
+fertilized it. There is no difficulty in restoring the ancient channels,
+or in constructing new, and thus watering not only all the soil that the
+wisdom of the Pharaohs had improved, but much additional land. Hundreds
+of square miles of arid sand waste would thus be converted into fields
+of perennial verdure, and the geography of Lower Egypt would be thereby
+sensibly changed. If the canal succeeds, considerable towns will grow up
+at once at both ends of the channel, and at intermediate points, all
+depending on the maintenance of aqueducts from the Nile, both for water
+and for the irrigation of the neighboring fields which are to supply
+them with bread. Important interests will thus be created, which will
+secure the permanence of the hydraulic works and of the geographical
+changes produced by them, and Suez, or Port Said, or the city at Lake
+Timsah, may become the capital of the government which has been so long
+established at Cairo.
+
+
+_Canal across the Isthmus of Darien._
+
+The most colossal project of canalization ever suggested, whether we
+consider the physical difficulties of its execution, the magnitude and
+importance of the waters proposed to be united, or the distance which
+would be saved in navigation, is that of a channel between the Gulf of
+Mexico and the Pacific, across the Isthmus of Darien. I do not now speak
+of a lock canal, by way of the Lake of Nicaragua or any other route--for
+such a work would not differ essentially from other canals, and would
+scarcely possess a geographical character--but of an open cut between
+the two seas. It has been by no means shown that the construction of
+such a channel is possible, and, if it were opened, it is highly
+probable that sand bars would accumulate at both entrances, so as to
+obstruct any powerful current through it. But if we suppose the work to
+be actually accomplished, there would be, in the first place, such a
+mixture of the animal and vegetable life of the two great oceans as I
+have stated to be likely to result from the opening of the Suez Canal
+between two much smaller basins. In the next place, if the channel were
+not obstructed by sand bars, it might sooner or later be greatly widened
+and deepened by the mechanical action of the current through it, and
+consequences, not inferior in magnitude to any physical revolution which
+has taken place since man appeared upon the earth, might result from it.
+
+What those consequences would be is in a great degree matter of pure
+conjecture, and there is much room for the exercise of the imagination
+on the subject; but, as more than one geographer has suggested, there is
+one possible result which throws all other conceivable effects of such a
+work quite into the shade. I refer to changes in the course of the two
+great oceanic rivers, the Gulf Stream and the corresponding current on
+the Pacific side of the isthmus. The warm waters which the Gulf Stream
+transports to high latitudes and then spreads out, like an expanded
+hand, along the eastern shores of the Atlantic, give out, as they cool,
+heat enough to raise the mean temperature of Western Europe several
+degrees. In fact, the Gulf Stream is the principal cause of the
+superiority of the climate of Western Europe over those of Eastern
+America and Eastern Asia in the corresponding latitudes. All the
+meteorological conditions of the former region are in a great measure
+regulated by it, and hence it is the grandest and most beneficent of all
+purely geographical phenomena. We do not yet know enough of the laws
+which govern the movements of this mighty flood of warmth and life to be
+able to say whether its current would be perceptibly affected by the
+severance of the Isthmus of Darien; but as it enters and sweeps round
+the Gulf of Mexico, it is possible that the removal of the resistance of
+the land which forms the western shore of that sea, might allow the
+stream to maintain its original westward direction, and join itself to
+the tropical current of the Pacific.
+
+The effect of such a change would be an immediate depression of the mean
+temperature of Western Europe to the level of that of Eastern America,
+and perhaps the climate of the former continent might become as
+excessive as that of the latter, or even a new "ice period" be
+occasioned by the withdrawal of so important a source of warmth from the
+northern zones. Hence would result the extinction of vast multitudes of
+land and sea plants and animals, and a total revolution in the domestic
+and rural economy of human life in all those countries from which the
+New World has received its civilized population. Other scarcely less
+startling consequences may be imagined as possible; but the whole
+speculation is too dreary, distant, and improbable to deserve to be long
+indulged in.[482]
+
+
+_Canals to the Dead Sea._
+
+The project of Captain Allen for opening a new route to India by cuts
+between the Mediterranean and the Dead Sea, and between the Dead Sea and
+the Red Sea, presents many interesting considerations.[483] The
+hypsometrical observations of Bertou, Roth, and others, render it highly
+probable, if not certain, that the watershed in the Wadi-el-Araba
+between the Dead Sea and the Red Sea is not less than three hundred feet
+above the mean level of the latter, and if this is so, the execution of
+a canal from the one sea to the other is quite out of the question. But
+the summit level between the Mediterranean and the Jordan, near Jezreel,
+is believed to be little, if at all, more than one hundred feet above
+the sea, and the distance is so short that the cutting of a channel
+through the dividing ridge would probably be found by no means an
+impracticable undertaking. Although, therefore, we have no reason to
+believe it possible to open a navigable channel to the east by way of
+the Dead Sea, there is not much doubt that the basin of the latter might
+be made accessible from the Mediterranean.
+
+The level of the Dead Sea lies 1,316.7 feet below that of the ocean. It
+is bounded east and west by mountain ridges, rising to the height of
+from 2,000 to 4,000 feet above the ocean. From its southern end, a
+depression called the Wadi-el-Araba extends to the Gulf of Akaba, the
+eastern arm of the Red Sea. The Jordan empties into its northern
+extremity, after having passed through the Lake of Tiberias at an
+elevation of 663.4 feet above the Dead Sea, or 653.3 below the
+Mediterranean, and drains a considerable valley north of the lake, as
+well as the plain of Jericho, which lies between the lake and the sea.
+If the waters of the Mediterranean were admitted freely into the basin
+of the Dead Sea, they would raise its surface to the general level of
+the ocean, and consequently flood all the dry land below that level
+within the basin.
+
+I do not know that accurate levels have been taken in the valley of the
+Jordan above the Lake of Tiberias, and our information is very vague as
+to the hypsometry of the northern part of the Wadi-el-Araba. As little
+do we know where a contour line, carried around the basin at the level
+of the Mediterranean, would strike its eastern and western borders. We
+cannot, therefore, accurately compute the extent of now dry land which
+would be covered by the admission of the waters of the Mediterranean, or
+the area of the inland sea which would be thus created. Its length,
+however, would certainly exceed one hundred and fifty miles, and its
+mean breadth, including its gulfs and bays, could scarcely be less than
+fifteen, perhaps even twenty. It would cover very little ground now
+occupied by civilized or even uncivilized man, though some of the soil
+which would be submerged--for instance, that watered by the Fountain of
+Elisha and other neighboring sources--is of great fertility, and, under
+a wiser government and better civil institutions, might rise to
+importance, because, from its depression, it possesses a very warm
+climate, and might supply Southeastern Europe with tropical products
+more readily than they can be obtained from any other source. Such a
+canal and sea would be of no present commercial importance, because they
+would give access to no new markets or sources of supply; but when the
+fertile valleys and the deserted plains east of the Jordan shall be
+reclaimed to agriculture and civilization, these waters would furnish a
+channel of communication which might become the medium of a very
+extensive trade.
+
+Whatever might be the economical results of the opening and filling of
+the Dead Sea basin, the creation of a new evaporable area, adding not
+less than 2,000 or perhaps 3,000 square miles to the present fluid
+surface of Syria, could not fail to produce important meteorological
+effects. The climate of Syria would be tempered, its precipitation and
+its fertility increased, the courses of its winds and the electrical
+condition of its atmosphere modified. The present organic life of the
+valley would be extinguished, and many tribes of plants and animals
+would emigrate from the Mediterranean to the new home which human art
+had prepared for them. It is possible, too, that the addition of 1,300
+feet, or forty atmospheres, of hydrostatic pressure upon the bottom of
+the basin might disturb the equilibrium between the internal and the
+external forces of the crust of the earth at this point of abnormal
+configuration, and thus produce geological convulsions the intensity of
+which cannot be even conjectured.
+
+
+_Maritime Canals in Greece._
+
+A maritime canal executed and another projected in ancient times, the
+latter of which is again beginning to excite attention, deserve some
+notice, though their importance is of a commercial rather than a
+geographical character. The first of these is the cut made by Xerxes
+through the rock which connects the promontory of Mount Athos with the
+mainland; the other, a navigable canal through the Isthmus of Corinth.
+In spite of the testimony of Herodotus and Thucydides, the Romans
+classed the canal of Xerxes among the fables of "mendacious Greece," and
+yet traces of it are perfectly distinct at the present day through its
+whole extent, except at a single point where, after it had become so
+choked as to be no longer navigable, it was probably filled up to
+facilitate communication by land between the promontory and the country
+in the rear of it.
+
+If the fancy kingdom of Greece shall ever become a sober reality, escape
+from its tutelage and acquire such a moral as well as political status
+that its own capitalists--who now prefer to establish themselves and
+employ their funds anywhere else rather than in their native land--have
+any confidence in the permanency of its institutions, a navigable
+channel will no doubt be opened between the gulfs of Lepanto and AEgina.
+The annexation of the Ionian Islands to Greece will make such a work
+almost a political necessity, and it would not only furnish valuable
+facilities for domestic intercourse, but become an important channel of
+communication between the Levant and the countries bordering on the
+Adriatic, or conducting their trade through that sea.
+
+As I have said, the importance of this latter canal and of a navigable
+channel between Mount Athos and the continent would be chiefly
+commercial, but both of them would be conspicuous instances of the
+control of man over nature in a field where he has thus far done little
+to interfere with her spontaneous arrangements. If they were constructed
+upon such a scale as to admit of the free passage of the water through
+them, in either direction, as the prevailing winds should impel it, they
+would exercise a certain influence on the coast currents, which are
+important as hydrographical elements, and also as producing abrasion of
+the coast and a drift at the bottom of seas, and hence would be entitled
+to a higher rank than simply as artificial means of transit.
+
+
+_Canal of Saros._
+
+It has been thought practicable to cut a canal across the peninsula of
+Gallipoli from the outlet of the Sea of Marmora into the Gulf of Saros.
+It may be doubted whether the mechanical difficulties of such a work
+would not be found insuperable; but when Constantinople shall recover
+the important political and commercial rank which naturally belongs to
+her, the execution of such a canal will be recommended by strong reasons
+of military expediency, as well as by the interests of trade. An open
+channel across the peninsula would divert a portion of the water which
+now flows through the Dardanelles, diminish the rapidity of that
+powerful current, and thus in part remove the difficulties which
+obstruct the navigation of the strait. It would considerably abridge the
+distance by water between Constantinople and the northern coast of the
+AEgean, and it would have the important advantage of obliging an enemy to
+maintain two blockading fleets instead of one.
+
+
+_Cape Cod Canal._
+
+The opening of a navigable cut through the narrow neck which separates
+the southern part of Cape Cod Bay in Massachusetts from the Atlantic,
+was long ago suggested, and there are few coast improvements on the
+Atlantic shores of the United States which are recommended by higher
+considerations of utility. It would save the most important coasting
+trade of the United States the long and dangerous navigation around Cape
+Cod, afford a new and safer entrance to Boston harbor for vessels from
+Southern ports, secure a choice of passages, thus permitting arrivals
+upon the coast and departures from it at periods when wind and weather
+might otherwise prevent them, and furnish a most valuable internal
+communication in case of coast blockade by a foreign power. The
+difficulties of the undertaking are no doubt formidable, but the expense
+of maintenance and the uncertainty of the effects of currents setting
+through the new strait are still more serious objections.
+
+
+_Diversion of the Nile._
+
+Perhaps the most remarkable project of great physical change, proposed
+or threatened in earlier ages, is that of the diversion of the Nile from
+its natural channel, and the turning of its current into either the
+Libyan desert or the Red Sea. The Ethiopian or Abyssinian princes more
+than once menaced the Memlouk sultans with the execution of this
+alarming project, and the fear of so serious an evil is said to have
+induced the Moslems to conciliate the Abyssinian kings by large
+presents, and by some concessions to the oppressed Christians of
+Egypt.[484] Indeed, Arabic historians affirm that in the tenth century
+the Ethiopians dammed the river, and, for a whole year, cut off its
+waters from Egypt. The probable explanation of this story is to be found
+in a season of extreme drought, such as have sometimes occurred in the
+valley of the Nile. About the beginning of the sixteenth century,
+Albuquerque the "Terrible" revived the scheme of turning the Nile into
+the Red Sea, with the hope of destroying the transit trade through Egypt
+by way of Kesseir. In 1525 the King of Portugal was requested by the
+Emperor of Abyssinia to send him engineers for that purpose; a successor
+of that prince threatened to attempt the project about the year 1700,
+and even as late as the French occupation of Egypt, the possibility of
+driving out the intruder by this means was suggested in England.
+
+It cannot be positively affirmed that the diversion of the waters of the
+Nile to the Red Sea is impossible. In the chain of mountains which
+separates the two valleys, Brown found a deep depression or wadi,
+extending from the one to the other, at no great elevation above the bed
+of the river. The Libyan desert is so much higher than the Nile below
+the junction of the two principal branches at Khartum, that there is no
+reason to believe a new channel for their united waters could be found
+in that direction; but the Bahr-el-Abiad flows through, if it does not
+rise in, a great table land, and some of its tributaries are supposed to
+communicate in the rainy season with branches of great rivers flowing in
+quite another direction. Hence it is probable that a portion at least of
+the waters of this great arm of the Nile--and perhaps a quantity the
+abstraction of which would be sensibly felt in Egypt--might be sent to
+the Atlantic by the Niger, lost in the inland lakes of Central Africa,
+or employed to fertilize the Libyan sand wastes.
+
+Admitting the possibility of turning the whole river into the Red Sea,
+let us consider the probable effect of the change. First and most
+obvious is the total destruction of the fertility of Middle and Lower
+Egypt, the conversion of that part of the valley into a desert, and the
+extinction of its imperfect civilization, if not the absolute
+extirpation of its inhabitants. This is the calamity threatened by the
+Abyssinian princes and the ferocious Portuguese warrior, and feared by
+the sultans of Egypt. Beyond these immediate and palpable consequences
+neither party then looked; but a far wider geographical area, and far
+more extensive and various human interests, would be affected by the
+measure. The spread of the Nile during the annual inundation covers, for
+many weeks, several thousand square miles with water, and at other
+seasons of the year pervades the same and even a larger area with
+moisture by infiltration. The abstraction of so large an evaporable
+surface from the southern shores of the Mediterranean could not but
+produce important effects on many meteorological phenomena, and the
+humidity, the temperature, the electrical condition and the atmospheric
+currents of Northeastern Africa might be modified to a degree that would
+sensibly affect the climate of Europe.
+
+The Mediterranean, deprived of the contributions of the Nile, would
+require a larger supply, and of course a stronger current, of water from
+the Atlantic through the Straits of Gibraltar; the proportion of salt it
+contains would be increased, and the animal life of at least its
+southern borders would be consequently modified; the current which winds
+along its southern, eastern, and northeastern shores would be diminished
+in force and volume, if not destroyed altogether, and its basin and its
+harbors would be shoaled by no new deposits from the highlands of inner
+Africa.
+
+In the much smaller Red Sea, more immediately perceptible, if not
+greater, effects, would be produced. The deposits of slime would reduce
+its depth, and perhaps, in the course of ages, divide it into an inland
+and an open sea; its waters would be more or less freshened, and its
+immensely rich marine fauna and flora changed in character and
+proportion, and, near the mouth of the river, perhaps even destroyed
+altogether; its navigable channels would be altered in position and
+often quite obstructed; the flow of its tides would be modified by the
+new geographical conditions; the sediment of the river would form new
+coast lines and lowlands, which would be covered with vegetation, and
+probably thereby produce sensible climatic changes.
+
+
+_Changes in the Caspian._
+
+The Russian Government has contemplated the establishment of a nearly
+direct water communication between the Caspian Sea and the Sea of Azoff,
+partly by natural and partly by artificial channels, and there are now
+navigable canals between the Don and the Volga; but these works, though
+not wanting in commercial and political interest, do not possess any
+geographical importance. It is, however, very possible to produce
+appreciable geographical changes in the basin of the Caspian by the
+diversion of the great rivers which flow from Central Russia. The
+surface of the Caspian is eighty-three feet below the level of the Sea
+of Azoff, and its depression has been explained upon the hypothesis that
+the evaporation exceeds the supply derived, directly and indirectly,
+from precipitation, though able physicists now maintain that the sinking
+of this sea is due to a subsidence of its bottom from geological causes.
+At Tsaritsin, the Don, which empties into the Sea of Azoff, and the
+Volga, which pours into the Caspian, approach each other within ten
+miles. Near this point, by means of open or subterranean canals, the Don
+might be turned into the Volga, or the Volga into the Don. If we suppose
+the whole or a large proportion of the waters of the Don to be thus
+diverted from their natural outlet and sent down to the Caspian, the
+equilibrium between the evaporation from that sea and its supply of
+water might be restored, or its level even raised above its ancient
+limits. If the Volga were turned into the Sea of Azoff, the Caspian
+would be reduced in dimensions until the balance between loss and gain
+should be reestablished, and it would occupy a much smaller area than at
+present. Such changes in the proportion of solid and fluid surface would
+have some climatic effects in the territory which drains into the
+Caspian, and on the other hand, the introduction of a greater quantity
+of fresh water into the Sea of Azoff would render that gulf less saline,
+affect the character and numbers of its fish, and perhaps be not wholly
+without sensible influence on the water of the Black Sea.
+
+
+_Improvements in North American Hydrography._
+
+We are not yet well enough acquainted with the geography of Central
+Africa, or of the interior of South America, to conjecture what
+hydrographical revolutions might there be wrought; but from the fact
+that many important rivers in both continents drain extensive table
+lands, of very moderate inclination, there is reason to suppose that
+important changes in the course of rivers might be accomplished. Our
+knowledge of the drainage of North America is much more complete, and it
+is certain that there are numerous points where the courses of great
+rivers, or the discharge of considerable lakes, might be completely
+diverted, or at least partially directed into different channels.
+
+The surface of Lake Erie is 565 feet above that of the Hudson at Albany,
+and it is so near the level of the great plain lying east of it, that it
+was found practicable to supply the western section of the canal, which
+unites it with the Hudson, with water from the lake, or rather from the
+Niagara which flows out of it. Hence a channel might be constructed,
+which would draw off into the valley of the Genesee any desirable
+proportion of the water naturally discharged by the Niagara. The
+greatest depth of water yet sounded in Lake Erie is but two hundred and
+seventy feet, the mean depth one hundred and twenty. Open canals
+parallel with the Niagara, or directly toward the Genesee, might be
+executed upon a scale which would exercise an important influence on the
+drainage of the lake, if there were any adequate motive for such an
+undertaking. Still easier would it be to create additional outlets for
+the waters of Lake Superior at the Saut St. Mary--where the river which
+drains the lake descends twenty-two feet in a single mile--and thus
+produce incalculable effects, both upon that lake and upon the great
+chain of inland waters which communicate with it.
+
+The summit level between Lake Michigan and the Des Plaines, a tributary
+of the Mississippi, is only twenty-seven feet above the lake, and the
+intervening distance is but a very few miles. It has often been proposed
+to cut an open channel across this ridge, and there is no doubt of the
+practicability of the project. Were this accomplished, although such a
+cut would not, of itself, form a navigable canal, a part of the waters
+of Lake Michigan would be contributed to the Gulf of Mexico, instead of
+to that of St. Lawrence, and the flow might be so regulated as to keep
+the Illinois and the Mississippi at flood at all seasons of the year.
+The increase in the volume of these rivers would augment their velocity
+and their transporting power, and consequently, the erosion of their
+banks and the deposit of slime in the Gulf of Mexico, while the
+introduction of a larger body of cold water into the beds of these
+rivers would very probably produce a considerable effect on the animal
+life that peoples them. The diversion of water from the common basin of
+the great lakes through a new channel, in a direction opposite to their
+natural discharge, would not be absolutely without influence on the St.
+Lawrence, though probably the effect would be too small to be in any way
+perceptible.
+
+
+_Diversion of the Rhine._
+
+The interference of physical improvements with vested rights and ancient
+arrangements, is a more formidable obstacle in old countries than in
+new, to enterprises involving anything approaching to a geographical
+revolution. Hence such projects meet with stronger opposition in Europe
+than in America, and the number of probable changes in the face of
+nature in the former continent is proportionally less. I have noticed
+some important hydraulic improvements as already executed or in progress
+in Europe, and I may refer to some others as contemplated or suggested.
+One of these is the diversion of the Rhine from its present channel
+below Ragatz, by a cut through the narrow ridge near Sargans, and the
+consequent turning of its current into the Lake of Wallenstadt. This
+would be an extremely easy undertaking, for the ridge is but twenty
+feet above the level of the Rhine, and hardly two hundred yards wide.
+There is no present adequate motive for this diversion, but it is easy
+to suppose that it may become advisable within no long period. The
+navigation of the Lake of Constance is rapidly increasing in importance,
+and the shoaling of the eastern end of that lake by the deposits of the
+Rhine may require a remedy which can be found by no other so ready means
+as the discharge of that river into the Lake of Wallenstadt. The
+navigation of this latter lake is not important, nor is it ever likely
+to become so, because the rocky and precipitous character of its shores
+renders their cultivation impossible. It is of great depth, and its
+basin is capacious enough to receive and retain all the sediment which
+the Rhine would carry into it for thousands of years.
+
+
+_Draining of the Zuiderzee._
+
+I have referred to the draining of the Lake of Haarlem as an operation
+of great geographical as well as economical and mechanical interest. A
+much more gigantic project, of a similar character, is now engaging the
+attention of the Netherlandish engineers. It is proposed to drain the
+great salt-water basin called the Zuiderzee. This inland sea covers an
+area of not less than two thousand square miles, or about one million
+three hundred thousand acres. The seaward half, or that portion lying
+northwest of a line drawn from Enkhuizen to Stavoren, is believed to
+have been converted from a marsh to an open bay since the fifth century
+after Christ, and this change is ascribed, partly if not wholly, to the
+interference of man with the order of nature. The Zuiderzee communicates
+with the sea by at least six considerable channels, separated from each
+other by low islands, and the tide rises within the basin to the height
+of three feet. To drain the Zuiderzee, these channels must first be
+closed and the passage of the tidal flood through them cut off. If this
+be done, the coast currents will be restored approximately to the lines
+they followed fourteen or fifteen centuries ago, and there can be little
+doubt that an appreciable effect will thus be produced upon all the
+tidal phenomena of that coast, and, of course, upon the maritime
+geography of Holland.
+
+A ring dike and canal must then be constructed around the landward side
+of the basin, to exclude and carry off the fresh-water streams which now
+empty into it. One of these, the Ijssel, a considerable river, has a
+course of eighty miles, and is, in fact, one of the outlets of the
+Rhine, though augmented by the waters of several independent
+tributaries. These preparations being made, and perhaps transverse dikes
+erected at convenient points for dividing the gulf into smaller
+portions, the water must be pumped out by machinery, in substantially
+the same way as in the case of the Lake of Haarlem. No safe calculations
+can be made as to the expenditure of time and money required for the
+execution of this stupendous enterprise, but I believe its
+practicability is not denied by competent judges, though doubts are
+entertained as to its financial expediency. The geographical results of
+this improvement would be analogous to those of the draining of the Lake
+of Haarlem, but many times multiplied in extent, and its meteorological
+effects, though perhaps not perceptible on the coast, could hardly fail
+to be appreciable in the interior of Holland.
+
+
+_Waters of the Karst._
+
+The singular structure of the Karst, the great limestone plateau lying
+to the north of Trieste, has suggested some engineering operations which
+might be attended with sensible effects upon the geography of the
+province. I have described this table land as, though now bare of
+forests, and almost of vegetation, having once been covered with woods,
+and as being completely honeycombed by caves through which the drainage
+of that region is conducted. Schmidl has spent years in studying the
+subterranean geography and hydrography of this singular district, and
+his discoveries, and those of earlier cave-hunters, have led to various
+proposals of physical improvement of a novel character. Many of the
+underground water courses of the Karst are without visible outlet, and,
+in some instances at least, they, no doubt, send their waters, by deep
+channels, to the Adriatic.[485] The city of Trieste is very
+insufficiently provided with fresh water. It has been thought
+practicable to supply this want by tunnelling through the wall of the
+plateau, which rises abruptly in the rear of the town, until some
+subterranean stream is encountered, the current of which can be
+conducted to the city. More visionary projectors have gone further, and
+imagined that advantage might be taken of the natural tunnels under the
+Karst for the passage of roads, railways, and even navigable canals. But
+however chimerical these latter schemes may seem, there is every reason
+to believe that art might avail itself of these galleries for improving
+the imperfect drainage of the champaign country bounded by the Karst,
+and that stopping or opening the natural channels might very much modify
+the hydrography of an extensive region.
+
+
+_Subterranean Waters of Greece._
+
+There are parts of continental Greece which resemble the Karst and the
+adjacent plains in being provided with a natural subterranean drainage.
+The superfluous waters run off into limestone caves called _catavothra_
+([Greek: katabothra]). In ancient times, the entrances to the catavothra
+were enlarged or partially closed as the convenience of drainage or
+irrigation required, and there is no doubt that similar measures might
+be adopted at the present day with great advantage both to the salubrity
+and the productiveness of the regions so drained.
+
+
+_Soil below Rock._
+
+One of the most singular changes of natural surface effected by man is
+that observed by Beechey and by Barth at Lin Tefla, and near Gebel
+Genunes, in the district of Ben Gasi, in Northern Africa. In this region
+the superficial stratum originally consisted of a thin sheet of rock
+covering a layer of fertile earth. This rock has been broken up, and,
+when not practicable to find use for it in fences, fortresses, or
+dwellings, heaped together in high piles, and the soil, thus bared of
+its stony shell, has been employed for agricultural purposes.[486] If we
+remember that gunpowder was unknown at the period when these remarkable
+improvements were executed, and of course that the rock could have been
+broken only with the chisel and wedge, we must infer that land had at
+that time a very great pecuniary value, and, of course, that the
+province, though now exhausted, and almost entirely deserted by man, had
+once a dense population.
+
+
+_Covering Rock with Earth._
+
+If man has, in some cases, broken up rock to reach productive ground
+beneath, he has, in many other instances, covered bare ledges, and
+sometimes extensive surfaces of solid stone, with fruitful earth,
+brought from no inconsiderable distance. Not to speak of the Campo Santo
+at Pisa, filled, or at least coated, with earth from the Holy Land, for
+quite a different purpose, it is affirmed that the garden of the
+monastery of St. Catherine at Mount Sinai is composed of Nile mud,
+transported on the backs of camels from the banks of that river. Parthey
+and older authors state that all the productive soil of the Island of
+Malta was brought over from Sicily.[487] The accuracy of the
+information may be questioned in both cases, but similar practices, on a
+smaller scale, are matter of daily observation in many parts of Southern
+Europe. Much of the wine of the Moselle is derived from grapes grown on
+earth carried high up the cliffs on the shoulders of men. In China, too,
+rock has been artificially covered with earth to an extent which gives
+such operations a real geographical importance, and the accounts of the
+importation of earth at Malta, and the fertilization of the rocks on
+Mount Sinai with slime from the Nile, may be not wholly without
+foundation.
+
+
+_Wadies of Arabia, Petraea._
+
+In the latter case, indeed, river sediment might be very useful as a
+manure, but it could hardly be needed as a soil; for the growth of
+vegetation in the wadies of the Sinaitic Peninsula shows that the
+disintegrated rock of its mountains requires only water to stimulate it
+to considerable productiveness. The wadies present, not unfrequently,
+narrow gorges, which might easily be closed, and thus accumulations of
+earth, and reservoirs of water to irrigate it, might be formed which
+would convert many a square mile of desert into flourishing date gardens
+and cornfields. Not far from Wadi Feiran, on the most direct route to
+Wadi Esh-Sheikh, is a very narrow pass called by the Arabs El Bueb (El
+Bab) or, The Gate, which might be securely closed to a very considerable
+height, with little labor or expense. Above this pass is a wide and
+nearly level expanse, containing a hundred acres, perhaps much more.
+This is filled up to a certain regular level with deposits brought down
+by torrents before the Gate, or Bueb, was broken through, and they have
+now worn down a channel in the deposits to the bed of the wadi. If a dam
+were constructed at the pass, and reservoirs built to retain the winter
+rains, a great extent of valley might be rendered cultivable.
+
+
+_Incidental Effects of Human Action._
+
+I have more than once alluded to the collateral and unsought
+consequences of human action as being often more momentous than the
+direct and desired results. There are cases where such incidental, or,
+in popular speech, accidental, consequences, though of minor importance
+in themselves, serve to illustrate natural processes; others, where, by
+the magnitude and character of the material traces they leave behind
+them, they prove that man, in primary or in more advanced stages of
+social life, must have occupied particular districts for a longer period
+than has been supposed by popular chronology. "On the coast of Jutland,"
+says Forchhammer, "wherever a bolt from a wreck or any other fragment of
+iron is deposited in the beach sand, the particles are cemented
+together, and form a very solid mass around the iron. A remarkable
+formation of this sort was observed a few years ago in constructing the
+sea wall of the harbor of Elsineur. This stratum, which seldom exceeded
+a foot in thickness, rested upon common beach sand, and was found at
+various depths, less near the shore, greater at some distance from it.
+It was composed of pebbles and sand, and contained a great quantity of
+pins, and some coins of the reign of Christian IV, between the beginning
+and the middle of the seventeenth century. Here and there, a coating of
+metallic copper had been deposited by galvanic action, and the presence
+of completely oxydized metallic iron was often detected. An
+investigation undertaken by Councillor Reinhard and myself, at the
+instance of the Society of Science, made it in the highest degree
+probable that this formation owed its origin to the street sweepings of
+the town, which had been thrown upon the beach, and carried off and
+distributed by the waves over the bottom of the harbor."[488] These and
+other familiar observations of the like sort show that a sandstone reef,
+of no inconsiderable magnitude, might originate from the stranding of a
+ship with a cargo of iron,[489] or from throwing the waste of an
+establishment for working metals into running water which might carry it
+to the sea.
+
+Parthey records a singular instance of unforeseen mischief from an
+interference with the arrangements of nature. A landowner at Malta
+possessed a rocky plateau sloping gradually toward the sea, and
+terminating in a precipice forty or fifty feet high, through natural
+openings in which the sea water flowed into a large cave under the rock.
+The proprietor attempted to establish salt works on the surface, and cut
+shallow pools in the rock for the evaporation of the water. In order to
+fill the salt pans more readily, he sank a well down to the cave
+beneath, through which he drew up water by a windlass and buckets. The
+speculation proved a failure, because the water filtered through the
+porous bottom of the pans, leaving little salt behind. But this was a
+small evil, compared with other destructive consequences that followed.
+When the sea was driven into the cave by violent west or northwest
+winds, it shot a _jet d'eau_ through the well to the height of sixty
+feet, the spray of which was scattered far and wide over the neighboring
+gardens and blasted the crops. The well was now closed with stones, but
+the next winter's storms hurled them out again, and spread the salt
+spray over the grounds in the vicinity as before. Repeated attempts were
+made to stop the orifice, but at the time of Parthey's visit the sea had
+thrice burst through, and it was feared that the evil was without
+remedy.[490]
+
+I have mentioned the great extent of the heaps of oyster and other
+shells left by the American Indians on the Atlantic coast of the United
+States. Some of the Danish kitchen-middens, which closely resemble them,
+are a thousand feet long, from one hundred and fifty to two hundred
+wide, and from six to ten high. These piles have an importance as
+geological witnesses, independent of their bearing upon human history.
+Wherever the coast line appears, from other evidence, to have remained
+unchanged in outline and elevation since they were accumulated, they are
+found near the sea, and not more than about ten feet above its level. In
+some cases they are at a considerable distance from the beach, and in
+these instances, so far as yet examined, there are proofs that the coast
+has advanced in consequence of upheaval or of fluviatile or marine
+deposit. Where they are altogether wanting, the coast seems to have sunk
+or been washed away by the sea. The constancy of these observations
+justifies geologists in arguing, where other evidence is wanting, the
+advance of land or sea respectively, or the elevation or depression of
+the former, from the position or the absence of these heaps alone.
+
+Every traveller in Italy is familiar with Monte Testaccio, the mountain
+of potsherds, at Rome; but this deposit, large as it is, shrinks into
+insignificance when compared with masses of similar origin in the
+neighborhood of older cities. The castaway pottery of ancient towns in
+Magna Graecia composes strata of such extent and thickness that they have
+been dignified with the appellation of the ceramic formation. The Nile,
+as it slowly changes its bed, exposes in its banks masses of the same
+material, so vast that the population of the world during the whole
+historical period would seem to have chosen this valley as a general
+deposit for its broken vessels.
+
+The fertility imparted to the banks of the Nile by the water and the
+slime of the inundations, is such that manures are little employed.
+Hence much domestic waste, which would elsewhere be employed to enrich
+the soil, is thrown out into vacant places near the town. Hills of
+rubbish are thus piled up which astonish the traveller almost as much as
+the solid pyramids themselves. The heaps of ashes and other household
+refuse collected on the borders and within the limits of Cairo were so
+large, that the removal of them by Ibrahim Pacha has been looked upon as
+one of the great works of the age.
+
+The soil near cities, the street sweepings of which are spread upon the
+ground as manure, is perceptibly raised by them and by other effects of
+human industry, and in spite of all efforts to remove the waste, the
+level of the ground on which large towns stand is constantly elevated.
+The present streets of Rome are twenty feet above those of the ancient
+city. The Appian way between Rome and Albano, when cleared out a few
+years ago, was found buried four or five feet deep, and the fields along
+the road were elevated nearly or quite as much. The floors of many
+churches in Italy, not more than six or seven centuries old, are now
+three or four feet below the adjacent streets, though it is proved by
+excavations that they were built as many feet above them.
+
+
+_Resistance to Great Natural Forces._
+
+I have often spoken of the greater and more subtile natural forces, and
+especially of geological agencies, as powers beyond human guidance or
+resistance. This is no doubt at present true in the main, but man has
+shown that he is not altogether impotent to struggle with even these
+mighty servants of nature, and his unconscious as well as his deliberate
+action may in some cases have increased or diminished the intensity of
+their energies. It is a very ancient belief that earthquakes are more
+destructive in districts where the crust of the earth is solid and
+homogeneous, than where it is of a looser and more interrupted
+structure. Aristotle, Pliny the elder, and Seneca believed that not only
+natural ravines and caves, but quarries, wells, and other human
+excavations, which break the continuity of the terrestrial strata and
+facilitate the escape of elastic vapors, have a sensible influence in
+diminishing the violence and preventing the propagation of the earth
+waves. In all countries subject to earthquakes this opinion is still
+maintained, and it is asserted that, both in ancient and in modern
+times, buildings protected by deep wells under or near them have
+suffered less from earthquakes than those the architects of which have
+neglected this precaution.[491]
+
+If the commonly received theory of the cause of earthquakes is
+true--that, namely, which ascribes them to the elastic force of gases
+accumulated or generated in subterranean reservoirs--it is evident that
+open channels of communication between such reservoirs and the
+atmosphere might serve as a harmless discharge of gases that would
+otherwise acquire destructive energy. The doubt is whether artificial
+excavations can be carried deep enough to reach the laboratory where the
+elastic fluids are distilled. There are, in many places, small natural
+crevices through which such fluids escape, and the source of them
+sometimes lies at so moderate a depth that they pervade the superficial
+soil and, as it were, transpire from it, over a considerable area. When
+the borer of an ordinary artesian well strikes into a cavity in the
+earth, imprisoned air often rushes out with great violence, and this has
+been still more frequently observed in sinking mineral-oil wells. In
+this latter case, the discharge of a vehement current of inflammable
+fluid sometimes continues for hours and even longer periods. These facts
+seem to render it not wholly improbable that the popular belief of the
+efficacy of deep wells in mitigating the violence of earthquakes is well
+founded.
+
+In general, light, wooden buildings are less injured by earthquakes than
+more solid structures of stone or brick, and it is commonly supposed
+that the power put forth by the earth wave is too great to be resisted
+by any amount of weight or solidity of mass that man can pile up upon
+the surface. But the fact that in countries subject to earthquakes many
+very large and strongly constructed palaces, temples, and other
+monuments have stood for centuries, comparatively uninjured, suggests a
+doubt whether this opinion is sound. The earthquake of the first of
+November, 1755, which was felt over a twelfth part of the earth's
+surface, was probably the most violent of which we have any clear and
+distinct account, and it seems to have exerted its most destructive
+force at Lisbon. It has often been noticed as a remarkable fact, that
+the mint, a building of great solidity, was almost wholly unaffected by
+the shock which shattered every house and church in the city, and its
+escape from the common ruin can hardly be accounted for except upon the
+supposition that its weight, compactness, and strength of material
+enabled it to resist an agitation of the earth which overthrew all
+weaker structures. On the other hand, a stone pier in the harbor of
+Lisbon, on which thousands of people had taken refuge, sank with its
+foundations to a great depth during the same earthquake; and it is plain
+that where subterranean cavities exist, at moderate depths, the erection
+of heavy masses upon them would tend to promote the breaking down of the
+strata which roof them over.
+
+No physicist, I believe, has supposed that man can avert the eruption of
+a volcano or diminish the quantity of melted rock which it pours out of
+the bowels of the earth; but it is not always impossible to divert the
+course of even a large current of lava. "The smaller streams of lava
+near Catania," says Ferrara, in describing the great eruption of 1669,
+"were turned from their course by building dry walls of stone as a
+barrier against them. * * * It was proposed to divert the main current
+from Catania, and fifty men, protected by hides, were sent with hooks
+and iron bars to break the flank of the stream near Belpasso.[492] When
+the opening was made, fluid lava poured forth and flowed rapidly toward
+Paterno; but the inhabitants of that place, not caring to sacrifice
+their own town to save Catania, rushed out in arms and put a stop to the
+operation."[493] In the eruption of Vesuvius in 1794, the viceroy saved
+from impending destruction the town of Portici, and the valuable
+collection of antiquities then deposited there but since removed to
+Naples, by employing several thousand men to dig a ditch above the town,
+by which the lava current was carried off in another direction.[494]
+
+
+_Effects of Mining._
+
+The excavations made by man, for mining and other purposes, may
+sometimes occasion disturbance of the surface by the subsidence of the
+strata above them, as in the case of the mine of Fahlun, but such
+accidents must always be too inconsiderable in extent to deserve notice
+in a geographical point of view. Such excavations, however, may
+interfere materially with the course of subterranean waters, and it has
+even been conjectured that the removal of large bodies of metallic ore
+from their original deposits might, at least locally, affect the
+magnetic and electrical condition of the earth's crust to a sensible
+degree.
+
+Accidental fires in mines of coal or lignite sometimes lead to
+consequences not only destructive to large quantities of valuable
+material, but may, directly or indirectly, produce results important in
+geography. The coal occasionally takes fire from the miners' lights or
+other fires used by them, and, if long exposed to air in deserted
+galleries, may be spontaneously kindled. Under favorable circumstances,
+a stratum of coal will burn till it is exhausted, and a cavity may be
+burnt out in a few months which human labor could not excavate in many
+years. Wittwer informs us that a coal mine at St. Etienne in Dauphiny
+has been burning ever since the fourteenth century, and that a mine near
+Duttweiler, another near Epterode, and a third at Zwickau, have been on
+fire for two hundred years. Such conflagrations not only produce
+cavities in the earth, but communicate a perceptible degree of heat to
+the surface, and the author just quoted cites cases where this heat has
+been advantageously employed in forcing vegetation.[495]
+
+
+_Espy's Theories._
+
+Espy's well known suggestion of the possibility of causing rain
+artificially, by kindling great fires, is not likely to be turned to
+practical account, but the speculations of this able meteorologist are
+not, for that reason, to be rejected as worthless. His labors exhibit
+great industry in the collection of facts, much ingenuity in dealing
+with them, remarkable insight into the laws of nature, and a ready
+perception of analogies and relations not obvious to minds less
+philosophically constituted. They have unquestionably contributed very
+essentially to the advancement of meteorological science. The
+possibility that the distribution and action of electricity may be
+considerably modified by long lines of iron railways and telegraph
+wires, is a kindred thought, and in fact rests much on the same
+foundation as the belief in the utility of lightning rods, but such
+influence is too obscure and too small to have been yet detected.
+
+
+_River Sediment._
+
+The manifestation of the internal heat of the earth at any given point
+is conditioned by the thickness of the crust at such point. The deposits
+of rivers tend to augment that thickness at their estuaries. The
+sediment of slowly flowing rivers emptying into shallow seas is spread
+over so great a surface that we can hardly imagine the foot or two of
+slime they let fall over a wide area in a century to form an element
+among even the infinitesimal quantities which compose the terms of the
+equations of nature. But some swift rivers, rolling mountains of fine
+earth, discharge themselves into deeply scooped gulfs or bays, and in
+such cases the deposit amounts, in the course of a few years, to a mass
+the transfer of which from the surface of a large basin, and its
+accumulation at a single point, may be supposed to produce other
+effects than those measurable by the sounding line. Now, almost all the
+operations of rural life, as I have abundantly shown, increase the
+liability of the soil to erosion by water. Hence, the clearing of the
+valley of the Ganges by man must have much augmented the quantity of
+earth transported by that river to the sea, and of course have
+strengthened the effects, whatever they may be, of thickening the crust
+of the earth in the Bay of Bengal. In such cases, then, human action
+must rank among geological influences.
+
+
+_Nothing Small in Nature._
+
+It is a legal maxim that "the law concerneth not itself with trifles,"
+_de minimus non curat lex_; but in the vocabulary of nature, little and
+great are terms of comparison only; she knows no trifles, and her laws
+are as inflexible in dealing with an atom as with a continent or a
+planet.[496] The human operations mentioned in the last few paragraphs,
+therefore, do act in the ways ascribed to them, though our limited
+faculties are at present, perhaps forever, incapable of weighing their
+immediate, still more their ultimate consequences. But our inability to
+assign definite values to these causes of the disturbance of natural
+arrangements is not a reason for ignoring the existence of such causes
+in any general view of the relations between man and nature, and we are
+never justified in assuming a force to be insignificant because its
+measure is unknown, or even because no physical effect can now be traced
+to it as its origin. The collection of phenomena must precede the
+analysis of them, and every new fact, illustrative of the action and
+reaction between humanity and the material world around it, is another
+step toward the determination of the great question, whether man is of
+nature or above her.
+
+
+
+
+FOOTNOTES:
+
+
+[1] In the Middle Ages, feudalism, and a nominal Christianity whose
+corruptions had converted the most beneficent of religions into the most
+baneful of superstitions, perpetuated every abuse of Roman tyranny, and
+added new oppressions and new methods of extortion to those invented by
+older despotisms. The burdens in question fell most heavily on the
+provinces that had been longest colonized by the Latin race, and these
+are the portions of Europe which have suffered the greatest physical
+degradation. "Feudalism," says Blanqui, "was a concentration of
+scourges. The peasant, stripped of the inheritance of his fathers,
+became the property of inflexible, ignorant, indolent masters; he was
+obliged to travel fifty leagues with their carts whenever they required
+it; he labored for them three days in the week, and surrendered to them
+half the product of his earnings during the other three; without their
+consent he could not change his residence, or marry. And why, indeed,
+should he wish to marry, when he could scarcely save enough to maintain
+himself? The Abbot Alcuin had twenty thousand slaves, called _serfs_,
+who were forever attached to the soil. This is the great cause of the
+rapid depopulation observed in the Middle Ages, and of the prodigious
+multitude of monasteries which sprang up on every side. It was doubtless
+a relief to such miserable men to find in the cloisters a retreat from
+oppression; but the human race never suffered a more cruel outrage,
+industry never received a wound better calculated to plunge the world
+again into the darkness of the rudest antiquity. It suffices to say that
+the prediction of the approaching end of the world, industriously spread
+by the rapacious monks at this time, was received without
+terror."--_Resume de l'Histoire du Commerce_, p. 156.
+
+The abbey of Saint-Germain-des-Pres, which, in the time of Charlemagne,
+had possessed a million of acres, was, down to the Revolution,
+still so wealthy, that the personal income of the abbot was 300,000
+livres. The abbey of Saint-Denis was nearly as rich as that of
+Saint-Germain-des-Pres.--LAVERGNE, _Economie Rurale de la France_,
+p. 104.
+
+Paul Louis Courier quotes from La Bruyere the following striking picture
+of the condition of the French peasantry in his time: "One sees certain
+dark, livid, naked, sunburnt, wild animals, male and female, scattered
+over the country and attached to the soil, which they root and turn over
+with indomitable perseverance. They have, as it were, an articulate
+voice, and when they rise to their feet, they show a human face. They
+are, in fact, men; they creep at night into dens, where they live on
+black bread, water, and roots. They spare other men the labor of
+ploughing, sowing, and harvesting, and therefore deserve some small
+share of the bread they have grown." "These are his own words," adds
+Courier; "he is speaking of the fortunate peasants, of those who had
+work and bread, and they were then the few."--_Petition a la Chambre des
+Deputis pour les Villageois que l'on empeche de danser._
+
+Arthur Young, who travelled in France from 1787 to 1789, gives, in the
+twenty-first chapter of his Travels, a frightful account of the burdens
+of the rural population even at that late period. Besides the regular
+governmental taxes, and a multitude of heavy fines imposed for trifling
+offences, he enumerates about thirty seignorial rights, the very origin
+and nature of some of which are now unknown, while those of some others,
+claimed and enforced by ecclesiastical as well as by temporal lords, are
+as repulsive to humanity and morality, as the worst abuses ever
+practised by heathen despotism. Most of these, indeed, had been commuted
+for money payments, and were levied on the peasantry as pecuniary
+imposts for the benefit of prelates and lay lords, who, by virtue of
+their nobility, were exempt from taxation. Who can wonder at the
+hostility of the French plebeian classes toward the aristocracy in the
+days of the Revolution?
+
+[2] The temporary depopulation of an exhausted soil may be, in some
+cases, a physical, though, like fallows in agriculture, a dear-bought
+advantage. Under favorable circumstances, the withdrawal of man and his
+flocks allows the earth to clothe itself again with forests, and in a
+few generations to recover its ancient productiveness. In the Middle
+Ages, worn-out fields were depopulated, in many parts of the Continent,
+by civil and ecclesiastical tyrannies, which insisted on the surrender
+of the half of a loaf already too small to sustain its producer. Thus
+abandoned, these lands often relapsed into the forest state, and, some
+centuries later, were again brought under cultivation with renovated
+fertility.
+
+[3] The subject of climatic change, with and without reference to human
+action as a cause, has been much discussed by Moreau de Jonnes, Dureau,
+de la Malle, Arago, Humboldt, Fuster, Gasparin, Becquerel, and many
+other writers in Europe, and by Noah Webster, Forry, Drake, and others
+in America. Fraas has endeavored to show, by the history of vegetation
+in Greece, not merely that clearing and cultivation have affected
+climate, but that change of climate has essentially modified the
+character of vegetable life. See his _Klima und Pflanzenwelt in der
+Zeit_.
+
+[4]
+
+ Gods Almagt wenkte van den troon,
+ En schiep elk volk een land ter woon:
+ Hier vestte Zij een grondgebied,
+ Dat Zij ons zelven scheppen liet.
+
+[5] The udometric measurements of Belgrand, reported in the _Annales
+Forestieres_ for 1854, and discussed by Valles in chap. vi of his
+_Etudes sur les Inondations_, constitute the earliest, and, in some
+respects, the most remarkable series known to me, of persevering and
+systematic observations bearing directly and exclusively upon the
+influence of human action on climate, or, to speak more accurately,
+on precipitation and natural drainage. The conclusions of Belgrand,
+however, and of Valles, who adopts them, have not been generally
+accepted by the scientific world, and they seem to have been, in part
+at least, refuted by the arguments of Hericourt and the observations
+of Cantegril, Jeandel, and Belland. See chapter iii: _The Woods_.
+
+[6] Verses addressed by G. C. to Sir Walter Raleigh.--HAKLUYT, i, p.
+668.
+
+[7]
+
+ ----I troer, at Synets Sands er lagt i Oeiet,
+ Mens dette kun er Redskab. Synet stroemmer
+ Fra Sjaelens Dyb, og Oeiets fine Nerver
+ Gaae ud fra Hjernens hemmelige Vaerksted.
+ HENRIK HERTZ, _Kong Rene's Datter_, sc. ii.
+
+ In the material eye, you think, sight lodgeth!
+ The _eye_ is but an organ. _Seeing_ streameth
+ From the soul's inmost depths. The fine perceptive
+ Nerve springeth from the brain's mysterious workshop.
+
+[8] Skill in marksmanship, whether with firearms or with other
+projectile weapons, depends more upon the training of the eye than is
+generally supposed, and I have often found particularly good shots to
+possess an almost telescopic vision. In the ordinary use of the rifle,
+the barrel serves as a guide to the eye, but there are sportsmen who
+fire with the but of the gun at the hip. In this case, as in the use of
+the sling, the lasso, and the bolas, in hurling the knife (see BABINET,
+_Lectures_, vii, p. 84), in throwing the boomerang, the javelin, or a
+stone, and in the employment of the blow pipe and the bow, the movements
+of the hand and arm are guided by that mysterious sympathy which exists
+between the eye and the unseeing organs of the body.
+
+In shooting the tortoises of the Amazon and its tributaries, the Indians
+use an arrow with a long twine and a float attached to it. Ave-Lallemant
+(_Die Benutzung der Palmen am Amazonenstrom_, p. 32) thus describes
+their mode of aiming: "As the arrow, if aimed directly at the floating
+tortoise, would strike it at a small angle, and glance from its flat and
+wet shell, the archers have a peculiar method of shooting. They are able
+to calculate exactly their own muscular effort, the velocity of the
+stream, the distance and size of the tortoise, and they shoot the arrow
+directly up into the air, so that it falls almost vertically upon the
+shell of the tortoise, and sticks in it." Analogous calculations--if
+such physico-mental operations can properly be so called--are made in
+the use of other missiles; for no projectile flies in a right line to
+its mark. But the exact training of the eye lies at the bottom of all of
+them, and marksmanship depends almost wholly upon the power of that
+organ, whose directions the blind muscles implicitly follow. It is
+perhaps not out of place to observe here that our English word aim comes
+from the Latin aestimo, I calculate or estimate. See WEDGWOOD'S
+_Dictionary of English Etymology_, and the note to the American edition,
+under _Aim_.
+
+Another proof of the control of the limbs by the eye has been observed
+in deaf-and-dumb schools, and others where pupils are first taught to
+write on large slates or blackboards. The writing is in large
+characters, the small letters being an inch or more high. They are
+formed with chalk or a slate pencil firmly grasped in the fingers, and
+by appropriate motions of the wrist, elbow, and shoulder, not of the
+finger joints. Nevertheless, when a pen is put into the hand of a pupil
+thus taught, his handwriting, though produced by a totally different set
+of muscles and muscular movements, is identical in character with that
+which he has practised on the blackboard.
+
+It has been much doubted whether the artists of the classic ages
+possessed a more perfect sight than those of modern times, or whether,
+in executing their minute mosaics and gem engravings, they used
+magnifiers. Glasses ground convex have been found at Pompeii, but they
+are too rudely fashioned and too imperfectly polished to have been of
+any practical use for optical purposes. But though the ancient artists
+may have had a microscopic vision, their astronomers cannot have had a
+telescopic power of sight; for they did not discover the satellites of
+Jupiter, which are often seen with the naked eye at Oormeeah, in Persia,
+and sometimes, as I can testify by personal observation, at Cairo.
+
+For a very remarkable account of the restoration of vision impaired from
+age, by judicious training, see _Lessons in Life_, by TIMOTHY TITCOMB,
+lesson xi.
+
+[9] _Antiquity of Man_, p. 377.
+
+[10] "One of them [the Indians] seated himself near me, and made from a
+fragment of quartz, with a simple piece of round bone, one end of which
+was hemispherical, with a small crease in it (as if worn by a thread)
+the sixteenth of an inch deep, an arrow head which was very sharp and
+piercing, and such as they use on all their arrows. The skill and
+rapidity with which it was made, without a blow, but by simply breaking
+the sharp edges with the creased bone by the strength of his hands--for
+the crease merely served to prevent the instrument from slipping,
+affording no leverage--was remarkable."--_Reports of Explorations and
+Surveys for Pacific Railroad_, vol. ii, 1855, _Lieut._ BECKWITH'S
+_Report_, p. 43.
+
+It has been said that stone weapons are not found in Sicily, except in
+certain caves half filled with the skeletons of extinct animals. If they
+have not been found in that island in more easily accessible localities,
+I suspect it is because eyes familiar with such objects have not sought
+for them. In January, 1854, I picked up an arrow head of quartz in a
+little ravine or furrow just washed out by a heavy rain, in a field near
+the Simeto. It is rudely fashioned, but its artificial character and its
+special purpose are quite unequivocal.
+
+[11] Probably no cultivated vegetable affords so good an opportunity of
+studying the laws of acclimation of plants as maize or Indian corn.
+Maize is grown from the tropics to at least lat. 47 deg. in Northeastern
+America, and farther north in Europe. Every two or three degrees of
+latitude brings you to a new variety, with new climatic adaptations, and
+the capacity of the plant to accommodate itself to new conditions of
+temperature and season seems almost unlimited. We may easily suppose a
+variety of this grain, which had become acclimated in still higher
+latitudes, to have been lost, and in such case the failure to raise a
+crop from seed brought from some distance to the south would not prove
+that the climate had become colder.
+
+Many persons now living remember that, when the common tomato was first
+introduced into Northern New England, it often failed to ripen; but, in
+the course of a very few years, it completely adapted itself to the
+climate, and now not only matures both its fruit and its seeds with as
+much certainty as any cultivated vegetable, but regularly propagates
+itself by self-sown seed. Meteorological observations, however, do not
+show any amelioration of the summer climate in those States within that
+period. See _Appendix_, No. 1.
+
+Maize and the tomato, if not new to human use, have not been long known
+to civilization, and were, very probably, reclaimed and domesticated at
+a much more recent period than the plants which form the great staples
+of agricultural husbandry in Europe and Asia. Is the great power of
+accomodation to climate possessed by them due to this circumstance?
+There is some reason to suppose that the character of maize has been
+sensibly changed by cultivation in South America; for, according to
+Poeppig, the ears of this grain found in old Peruvian tombs belong to
+varieties not now known in Peru.--_Travels in Peru_, chap. vii.
+
+[12] The cultivation of madder is said to have been introduced into
+Europe by an Oriental in the year 1765, and it was first planted in the
+neighborhood of Avignon. Of course, it has been grown in that district
+for less than a century; but upon soils where it has been a frequent
+crop, it is already losing much of its coloring properties.--LAVERGNE,
+_Economie Rurale de la France_, pp. 259-291.
+
+I believe there is no doubt that the cultivation of madder in the
+vicinity of Avignon is of recent introduction; but it appears from
+Fuller and other evidence, that this plant was grown in Europe before
+the middle of the seventeenth century. The madder brought to France from
+Persia may be of a different species, or, at least, variety. "Some two
+years since," says Fuller, "madder was sown by Sir Nicholas Crispe at
+Debtford, and I hope will have good success; first because it groweth in
+Zeland in the same (if not a more _northern_) _latitude_. Secondly,
+because _wild madder_ grows here in abundance; and why may not _tame
+madder_ if _cicurated_ by art. Lastly, because as good as any grew some
+thirty years since at Barn-Elms, in Surrey, though it quit not cost
+through some error in the first planter thereof, which now we hope will
+be rectified."--FULLER, _Worthies of England_, ii, pp. 57, 58.
+
+Perhaps the recent diseases of the olive, the vine, and the
+silkworm--the prevailing malady of which insect is supposed by some to
+be the effect of an incipient decay of the mulberry tree--may be, in
+part, due to changes produced in the character of the soil by exhaustion
+through long cultivation.
+
+[13] In many parts of New England there are tracts, miles in extent, and
+presenting all varieties of surface and exposure, which were partially
+cleared sixty or seventy years ago, and where little or no change in the
+proportion of cultivated ground, pasturage, and woodland has taken place
+since. In some cases, these tracts compose basins apparently scarcely at
+all exposed to any local influence in the way of percolation or
+infiltration of water toward or from neighboring valleys. But in such
+situations, apart from accidental disturbances, the ground is growing
+drier and drier, from year to year, springs are still disappearing, and
+rivulets still diminishing in their summer supply of water. A probable
+explanation of this is to be found in the rapid drainage of the surface
+of cleared ground, which prevents the subterranean natural reservoirs,
+whether cavities or merely strata of bibulous earth, from filling up.
+How long this process is to last before an equilibrium is reached, none
+can say. It may be, for years; it may be, for centuries.
+
+Livingstone states facts which favor the supposition that a secular
+desiccation is still going on in central Africa. When the regions where
+the earth is growing drier were cleared of wood, or, indeed, whether
+forests ever grew there, we are unable to say, but the change appears to
+have been long in progress. There is reason to suspect a similar
+revolution in Arabia Petraea. In many of the wadis, and particularly in
+the gorges between Wadi Feiran and Wadi Esh Sheikh, there are water-worn
+banks showing that, at no very remote period, the winter floods must
+have risen fifty feet in channels where the growth of acacias and
+tamarisks and the testimony of the Arabs concur to prove that they have
+not risen six feet within the memory or tradition of the present
+inhabitants. There is little probability that any considerable part of
+the Sinaitic peninsula has been wooded since its first occupation by
+man, and we must seek the cause of its increasing dryness elsewhere than
+in the removal of the forest.
+
+[14] The soil of newly subdued countries is generally in a high degree
+favorable to the growth of the fruits of the garden and the orchard, but
+usually becomes much less so in a very few years. Plums, of many
+varieties, were formerly grown, in great perfection and abundance, in
+many parts of New England where at present they can scarcely be reared
+at all; and the peach, which, a generation or two ago, succeeded
+admirably in the southern portion of the same States, has almost ceased
+to be cultivated there. The disappearance of these fruits is partly due
+to the ravages of insects, which have in later years attacked them; but
+this is evidently by no means the sole, or even the principal cause of
+their decay. In these cases, it is not to the exhaustion of the
+particular acres on which the fruit trees have grown that we are to
+ascribe their degeneracy, but to a general change in the condition of
+the soil or the air; for it is equally impossible to rear them
+successfully on absolutely new land in the neighborhood of grounds
+where, not long since, they bore the finest fruit.
+
+I remember being told, many years ago, by one of the earliest settlers
+of the State of Ohio, a very intelligent and observing person, that the
+apple trees raised there from seed sown soon after the land was cleared,
+bore fruit in less than half the time required to bring to bearing those
+reared from seed sown when the ground had been twenty years under
+cultivation.
+
+In the peat mosses of Denmark, Scotch firs and other trees not now
+growing in the same localities, are found in abundance. Every generation
+of trees leaves the soil in a different state from that in which it
+found it; every tree that springs up in a group of trees of another
+species than its own, grows under different influences of light and
+shade and atmosphere from its predecessors. Hence the succession of
+crops, which occurs in all natural forests, seems to be due rather to
+changes of condition than of climate. See chapter iii, _post_.
+
+[15] The nomenclature of meteorology is vague and sometimes equivocal.
+Not long since, it was suspected that the observers reporting to a
+scientific institution did not agree in their understanding of the mode
+of expressing the direction of the wind prescribed by their
+instructions. It was found, upon inquiry, that very many of them used
+the names of the compass-points to indicate the quarter _from_ which the
+wind blew, while others employed them to signify the quarter _toward_
+which the atmospheric currents were moving. In some instances, the
+observers were no longer within the reach of inquiry, and of course
+their tables of the wind were of no value.
+
+"Winds," says Mrs. Somerville, "are named from the points whence they
+blow, currents exactly the reverse. An easterly wind comes from the
+east; whereas an easterly current comes from the west, and flows toward
+the east."--_Physical Geography_, p. 229.
+
+There is no philological ground for this distinction, and it probably
+originated in a confusion of the terminations _-wardly_ and _-erly_,
+both of which are modern. The root of the former ending implies the
+direction _to_ or _to-ward_ which motion is supposed. It corresponds to,
+and is probably allied with, the Latin _versus_. The termination _-erly_
+is a corruption or softening of _-ernly_, easterly for easternly, and
+many authors of the seventeenth century so write it. In Hakluyt (i, p.
+2), _easterly_ is applied to place, "_easterly_ bounds," and means
+_eastern_. In a passage in Drayton, "_easterly_ winds" must mean winds
+_from_ the east; but the same author, in speaking of nations, uses
+_northerly_ for _northern_. Hakewell says: "The sonne cannot goe more
+_southernely_ from vs, nor come more _northernely_ towards vs." Holland,
+in his translation of Pliny, referring to the moon has: "When shee is
+_northerly_," and "shee is gone _southerly_." Richardson, to whom I am
+indebted for the above citations, quotes a passage from Dampier where
+_westerly_ is applied to the wind, but the context does not determine
+the direction. The only example of the termination in _-wardly_ given by
+this lexicographer is from Donne, where it means _toward_ the west.
+
+Shakspeare, in _Hamlet_ (v. ii), uses _northerly_ wind for wind _from_
+the north. Milton does not employ either of these terminations, nor were
+they known to the Anglo-Saxons, who, however, had adjectives of
+direction in _-an_ or _-en_, _-ern_ and _-weard_, the last always
+meaning the point _toward_ which motion is supposed, the others that
+_from_ which it proceeds.
+
+We use an _east_ wind, an _eastern_ wind, and an _easterly_ wind, to
+signify the same thing. The two former expressions are old, and constant
+in meaning; the last is recent, superfluous, and equivocal. See
+_Appendix_, No. 2.
+
+[16] I do not here speak of the vast prairie region of the Mississippi
+valley, which cannot properly be said ever to have been a field of
+British colonization; but of the original colonies, and their
+dependencies in the territory of the present United States, and in
+Canada. It is, however, equally true of the Western prairies as of the
+Eastern forest land, that they had arrived at a state of equilibrium,
+though under very different conditions.
+
+[17] The great fire of Miramichi in 1825, probably the most extensive
+and terrific conflagration recorded in authentic history, spread its
+ravages over nearly six thousand square miles, chiefly of woodland, and
+was of such intensity that it seemed to consume the very soil itself.
+But so great are the recuperative powers of nature, that, in twenty-five
+years, the ground was thickly covered again with trees of fair
+dimensions, except where cultivation and pasturage kept down the forest
+growth.
+
+[18] The English nomenclature of this geographical feature does not seem
+well settled. We have _bog_, _swamp_, _marsh_, _morass_,_ moor_, _fen_,
+_turf moss_, _peat moss_, _quagmire_, all of which, though sometimes
+more or less accurately discriminated, are often used interchangeably,
+or are perhaps employed, each exclusively, in a particular district. In
+Sweden, where, especially in the Lappish provinces, this terr-aqueous
+formation is very extensive and important, the names of its different
+kinds are more specific in their application. The general designation of
+all soils permanently pervaded with water is _Kaerr_. The elder Laestadius
+divides the _Kaerr_ into two genera: _Myror_ (sing. _myra_), and _Mossar_
+(sing. _mosse_). "The former," he observes, "are grass-grown, and
+overflowed with water through almost the whole summer; the latter are
+covered with mosses and always moist, but very seldom overflowed." He
+enumerates the following species of _Myra_, the character of which will
+perhaps be sufficiently understood by the Latin terms into which he
+translates the vernacular names, for the benefit of strangers not
+altogether familiar with the language and the subject: 1. _Hoemyror_,
+paludes graminosae. 2. _Dy_, paludes profundae. 3. _Flarkmyror_, or proper
+_kaerr_, paludes limosae. 4. _Fjaellmyror_, paludes uliginosae. 5.
+_Tufmyror_, paludes caespitosae. 6. _Rismyror_, paludes virgatae. 7.
+_Starraengar_, prata irrigata, with their subdivisions, dry _starraengar_
+or _risaengar_, wet _starraengar_ and _fraekengropar_. 8. _Poelar_, laeunae.
+9. _Goelar_, fossae inundatae. The _Mossar_, paludes turfosae, which are of
+great extent, have but two species: 1. _Torfmossar_, called also
+_Mossmyror_ and _Snottermyror_, and, 2. _Bjoernmossar_.
+
+The accumulations of stagnant or stagnating water originating in bogs
+are distinguished into _Tr[=a]sk_, stagna, and _Tjernar_ or _Tjaernar_
+(sing. _Tjern_ or _Tjaern_), stagnatiles. _Tr[=a]sk_ are pools fed by
+bogs, or water emanating from them, and their bottoms are slimy;
+_Tjernar_ are small _Traesk_ situated within the limits of _Mossar_.--L.
+L. LAESTADIUS, _om Moejligheten af Uppodlingar i Lappmarken_, pp. 23, 24.
+
+[19] Although the quantity of bog land in New England is less than in
+many other regions of equal area, yet there is a considerable extent of
+this formation in some of the Northeastern States. Dana (_Manual of
+Geology_, p. 614) states that the quantity of peat in Massachusetts is
+estimated at 120,000,000 cords, or nearly 569,000,000 cubic yards, but
+he does not give either the area or the depth of the deposits. In any
+event, however, bogs cover but a small percentage of the territory in
+any of the Northern States, while it is said that one tenth of the whole
+surface of Ireland is composed of bogs, and there are still extensive
+tracts of undrained marsh in England.
+
+Bogs, independently of their importance in geology as explaining the
+origin of some kinds of mineral coal, have a present value as
+repositories of fuel. Peat beds have sometimes a thickness of ten or
+twelve yards, or even more. A depth of ten yards would give 48,000 cubic
+yards to the acre. The greatest quantity of firewood yielded by the
+forests of New England to the acre is 100 cords solid measure, or 474
+cubic yards; but this comprises only the trunks and larger branches. If
+we add the small branches and twigs, it is possible that 600 cubic yards
+might, in some cases, be cut on an acre. This is only one eightieth part
+of the quantity of peat sometimes found on the same area. It is true
+that a yard of peat and a yard of wood are not the equivalents of each
+other, but the fuel on an acre of deep peat is worth much more than that
+on an acre of the best woodland. Besides this, wood is perishable, and
+the quantity on an acre cannot be increased beyond the amount just
+stated; peat is indestructible, and the beds are always growing.
+
+[20] "Aquatic plants have a utility in raising the level of marshy
+grounds, which renders them very valuable, and may well be called a
+geological function. * * *
+
+"The engineer drains ponds at a great expense by lowering the surface of
+the water; nature attains the same end, gratuitously, by raising the
+level of the soil without depressing that of the water; but she proceeds
+more slowly. There are, in the Landes, marshes where this natural
+filling has a thickness of four metres, and some of them, at first lower
+than the sea, have been thus raised and drained so as to grow summer
+crops, such, for example, as maize."--BOITEL, _Mise en valeur des Terres
+pauvres_, p. 227.
+
+The bogs of Denmark--the examination of which by Steenstrup and Vaupell
+has presented such curious results with respect to the natural
+succession of forest trees--appear to have gone through this gradual
+process of drying, and the birch, which grows freely in very wet soils,
+has contributed very effectually by its annual deposits to raise the
+surface above the water level, and thus to prepare the ground for the
+oak.--VAUPELL, _Boegens Indvandring_, pp. 39, 40.
+
+[21] Careful examination of the peat mosses in North Sjaelland--which are
+so abundant in fossil wood that, within thirty years, they have yielded
+above a million of trees--shows that the trees have generally fallen
+from age and not from wind. They are found in depressions on the
+declivities of which they grew, and they lie with the top lowest, always
+falling toward the bottom of the valley.--VAUPELL, _Boegens Indvandring i
+de Danske Skove_, pp. 10, 14.
+
+[22] The locust insect, _Clitus pictus_, which deposits its eggs in the
+American locust, _Robinia pseudacacia_, is one of these, and its ravages
+have been and still are most destructive to that very valuable tree, so
+remarkable for combining rapidity of growth with strength and durability
+of wood. This insect, I believe, has not yet appeared in Europe, where,
+since the so general employment of the _Robinia_ to clothe and protect
+embankments and the scarps of deep cuts on railroads, it would do
+incalculable mischief. As a traveller, however, I should find some
+compensation for this evil in the destruction of these acacia hedges,
+which as completely obstruct the view on hundreds of miles of French and
+Italian railways, as the garden walls of the same countries do on the
+ordinary roads. See _Appendix_, No. 4.
+
+[23] In the artificial woods of Europe, insects are far more numerous
+and destructive to trees than in the primitive forests of America, and
+the same remark may be made of the smaller rodents, such as moles, mice,
+and squirrels. In the dense native wood, the ground and the air are too
+humid, the depth of shade too great for many tribes of these creatures,
+while near the natural meadows and other open grounds, where
+circumstances are otherwise more favorable for their existence and
+multiplication, their numbers are kept down by birds, serpents, foxes,
+and smaller predacious quadrupeds. In civilized countries, these natural
+enemies of the worm, the beetle and the mole, are persecuted, sometimes
+almost exterminated, by man, who also removes from his plantations the
+decayed or wind-fallen trees, the shrubs and underwood, which, in a
+state of nature, furnished food and shelter to the borer and the rodent,
+and often also to the animals that preyed upon them. Hence the insect
+and the gnawing quadruped are allowed to increase, from the expulsion of
+the police which, in the natural wood, prevent their excessive
+multiplication, and they become destructive to the forest because they
+are driven to the living tree for nutriment and cover. The forest of
+Fontainebleau is almost wholly without birds, and their absence is
+ascribed by some writers to the want of water, which, in the thirsty
+sands of that wood, does not gather into running brooks; but the want of
+undergrowth is perhaps an equally good reason for their scarcity. In a
+wood of spontaneous growth, ordered and governed by nature, the squirrel
+does not attack trees, or at least the injury he may do is too trifling
+to be perceptible, but he is a formidable enemy to the plantation. "The
+squirrels bite the cones of the pine and consume the seed which might
+serve to restock the wood; they do still more mischief by gnawing off,
+near the leading shoot, a strip of bark, and thus often completely
+girdling the tree. Trees so injured must be felled, as they would never
+acquire a vigorous growth. The squirrel is especially destructive to the
+pine in Sologne, where he gnaws the bark of tress twenty or twenty-five
+years old." But even here, nature sometimes provides a compensation, by
+making the appetite of this quadruped serve to prevent an excessive
+production of seed cones, which tends to obstruct the due growth of the
+leading shoot. "In some of the pineries of Brittany which produce cones
+so abundantly as to strangle the development of the leading shoot of the
+maritime pine, it has been observed that the pines are most vigorous
+where the squirrels are most numerous, a result attributed to the
+repression of the cones by this rodent."--BOITEL, _Mise en valeur des
+Terres pauvres_, p. 50. See _Appendix_, No. 5.
+
+[24] The terrible destructiveness of man is remarkably exemplified in
+the chase of large mammalia and birds for single products, attended with
+the entire waste of enormous quantities of flesh, and of other parts of
+the animal, which are capable of valuable uses. The wild cattle of South
+America are slaughtered by millions for their hides and horns; the
+buffalo of North America for his skin or his tongue; the elephant, the
+walrus, and the narwhal for their tusks; the cetacea, and some other
+marine animals, for their oil and whalebone; the ostrich and other large
+birds, for their plumage. Within a few years, sheep have been killed in
+New England by whole flocks, for their pelts and suet alone, the flesh
+being thrown away; and it is even said that the bodies of the same
+quadrupeds have been used in Australia as fuel for limekilns. What a
+vast amount of human nutriment, of bone, and of other animal products
+valuable in the arts, is thus recklessly squandered! In nearly all these
+cases, the part which constitutes the motive for this wholesale
+destruction, and is alone saved, is essentially of insignificant value
+as compared with what is thrown away. The horns and hide of an ox are
+not economically worth a tenth part as much as the entire carcass.
+
+One of the greatest benefits to be expected from the improvements of
+civilization is, that increased facilities of communication will render
+it possible to transport to places of consumption much valuable material
+that is now wasted because the price at the nearest market will not pay
+freight. The cattle slaughtered in South America for their hides would
+feed millions of the starving population of the Old World, if their
+flesh could be economically preserved and transported across the ocean.
+
+We are beginning to learn a better economy in dealing with the inorganic
+world. The utilization--or, as the Germans more happily call it, the
+Verwerthung, the _beworthing_--of waste from metallurgical, chemical,
+and manufacturing establishments, is among the most important results of
+the application of science to industrial purposes. The incidental
+products from the laboratories of manufacturing chemists often become
+more valuable than those for the preparation of which they were erected.
+The slags from silver refineries, and even from smelting houses of the
+coarser metals, have not unfrequently yielded to a second operator a
+better return than the first had derived from dealing with the natural
+ore; and the saving of lead carried off in the smoke of furnaces has, of
+itself, given a large profit on the capital invested in the works. A few
+years ago, an officer of an American mint was charged with embezzling
+gold committed to him for coinage. He insisted, in his defence, that
+much of the metal was volatilized and lost in refining and melting, and
+upon scraping the chimneys of the melting furnaces and the roofs of the
+adjacent houses, gold enough was found in the soot to account for no
+small part of the deficiency.
+
+[25] It is an interesting and not hitherto sufficiently noticed fact,
+that the domestication of the organic world, so far as it has yet been
+achieved, belongs, not indeed to the savage state, but to the earliest
+dawn of civilization, the conquest of inorganic nature almost as
+exclusively to the most advanced stages of artificial culture. It is
+familiarly known to all who have occupied themselves with the psychology
+and habits of the ruder races, and of persons with imperfectly developed
+intellects in civilized life, that although these humble tribes and
+individuals sacrifice, without scruple, the lives of the lower animals
+to the gratification of their appetites and the supply of their other
+physical wants, yet they nevertheless seem to cherish with brutes, and
+even with vegetable life, sympathies which are much more feebly felt by
+civilized men. The popular traditions of the simpler peoples recognize a
+certain community of nature between man, brute animals, and even plants;
+and this serves to explain why the apologue or fable, which ascribes the
+power of speech and the faculty of reason to birds, quadrupeds, insects,
+flowers, and trees, is one of the earliest forms of literary
+composition.
+
+In almost every wild tribe, some particular quadruped or bird, though
+persecuted as a destroyer of more domestic beasts, or hunted for food,
+is regarded with peculiar respect, one might almost say, affection. Some
+of the North American aboriginal nations celebrate a propitiatory feast
+to the manes of the intended victim before they commence a bear hunt;
+and the Norwegian peasantry have not only retained an old proverb which
+ascribes to the same animal "_ti M[oe]nds Styrke og tolv M[oe]nds Vid_,"
+ten men's strength and twelve men's cunning, but they still pay to him
+something of the reverence with which ancient superstition invested him.
+The student of Icelandic literature will find in the saga of _Finnbogi
+hinn rami_ a curious illustration of this feeling, in an account of a
+dialogue between a Norwegian bear and an Icelandic champion--dumb show
+on the part of Bruin, and chivalric words on that of Finnbogi--followed
+by a duel, in which the latter, who had thrown away his arms and armor
+in order that the combatants might meet on equal terms, was victorious.
+Drummond Hay's very interesting work on Morocco contains many amusing
+notices of a similar feeling entertained by the Moors toward the
+redoubtable enemy of their flocks--the lion.
+
+This sympathy helps us to understand how it is that most if not all the
+domestic animals--if indeed they ever existed in a wild state--were
+appropriated, reclaimed and trained before men had been gathered into
+organized and fixed communities, that almost every known esculent plant
+had acquired substantially its present artificial character, and that
+the properties of nearly all vegetable drugs and poisons were known at
+the remotest period to which historical records reach. Did nature bestow
+upon primitive man some instinct akin to that by which she teaches the
+brute to select the nutritious and to reject the noxious vegetables
+indiscriminately mixed in forest and pasture?
+
+This instinct, it must be admitted, is far from infallible, and, as has
+been hundreds of times remarked by naturalists, it is in many cases not
+an original faculty but an acquired and transmitted habit. It is a fact
+familiar to persons engaged in sheep husbandry in New England--and I
+have seen it confirmed by personal observation--that sheep bred where
+the common laurel, as it is called, _Kalmia angustifolia_, abounds,
+almost always avoid browsing upon the leaves of that plant, while those
+brought from districts where laurel is unknown, and turned into pastures
+where it grows, very often feed upon it and are poisoned by it. A
+curious acquired and hereditary instinct, of a different character, may
+not improperly be noticed here. I refer to that by which horses bred in
+provinces where quicksands are common avoid their dangers or extricate
+themselves from them. See BREMONTIER, _Memoire sur les Dunes, Annales
+des Ponts et Chaussees_, 1833: _premier semestre_, pp. 155-157.
+
+It is commonly said in New England, and I believe with reason, that the
+crows of this generation are wiser than their ancestors. Scarecrows
+which were effectual fifty years ago are no longer respected by the
+plunderers of the cornfield, and new terrors must from time to time be
+invented for its protection. See _Appendix_, No. 6.
+
+Civilization has added little to the number of vegetable or animal
+species grown in our fields or bred in our folds, while, on the
+contrary, the subjugation of the inorganic forces, and the consequent
+extension of man's sway over, not the annual products of the earth only,
+but her substance and her springs of action, is almost entirely the work
+of highly refined and cultivated ages. The employment of the elasticity
+of wood and of horn, as a projectile power in the bow, is nearly
+universal among the rudest savages. The application of compressed air to
+the same purpose, in the blowpipe, is more restricted, and the use of
+the mechanical powers, the inclined plane, the wheel and axle, and even
+the wedge and lever, seems almost unknown except to civilized man. I
+have myself seen European peasants to whom one of the simplest
+applications of this latter power was a revelation.
+
+[26] The difference between the relations of savage life, and of
+incipient civilization, to nature, is well seen in that part of the
+valley of the Mississippi which was once occupied by the mound builders
+and afterward by the far less developed Indian tribes. When the tillers
+of the fields, which must have been cultivated to sustain the large
+population that once inhabited those regions perished, or were driven
+out, the soil fell back to the normal forest state, and the savages who
+succeeded the more advanced race interfered very little, if at all, with
+the ordinary course of spontaneous nature.
+
+[27] There is a possible--but only a possible--exception in the case of
+the American bison. See note on that subject in chap. iii, _post_.
+
+[28] Whatever may be thought of the modification of organic species by
+natural selection, there is certainly no evidence that animals have
+exerted upon any form of life an influence analogous to that of
+domestication upon plants, quadrupeds, and birds reared artificially by
+man; and this is as true of unforeseen as of purposely effected
+improvements accomplished by voluntary selection of breeding animals.
+
+[29] ----"And it may be remarked that, as the world has passed through
+these several stages of strife to produce a Christendom, so by relaxing
+in the enterprises it has learnt, does it tend downwards, through
+inverted steps, to wildness and the waste again. Let a people give up
+their contest with moral evil; disregard the injustice, the ignorance,
+the greediness, that may prevail among them, and part more and more with
+the Christian element of their civilization; and in declining this
+battle with sin, they will inevitably get embroiled with men. Threats of
+war and revolution punish their unfaithfulness; and if then, instead of
+retracing their steps, they yield again, and are driven before the
+storm, the very arts they had created, the structures they had raised,
+the usages they had established, are swept away; 'in that very day their
+thoughts perish.' The portion they had reclaimed from the young earth's
+ruggedness is lost; and failing to stand fast against man, they finally
+get embroiled with nature, and are thrust down beneath her ever-living
+hand."--MARTINEAU'S _Sermon_, "_The Good Soldier of Jesus Christ_."
+
+[30] The dependence of man upon the aid of spontaneous nature, in his
+most arduous material works, is curiously illustrated by the fact that
+one of the most serious difficulties to be encountered in executing the
+proposed gigantic scheme of draining the Zuiderzee in Holland, is that
+of procuring brushwood for the fascines to be employed in the
+embankments. See DIGGELEN'S pamphlet, "_Groote Werken in Nederland_."
+
+[31] In heavy storms, the force of the waves as they strike against a
+sea wall is from one and a half to two tons to the square foot, and
+Stevenson, in one instance at Skerryvore, found this force equal to
+three tons per foot.
+
+The seaward front of the breakwater at Cherbourg exposes a surface of
+about 2,500,000 square feet. In rough weather the waves beat against
+this whole face, though at the depth of twenty-two yards, which is the
+height of the breakwater, they exert a very much less violent motive
+force than at and near the surface of the sea, because this force
+diminishes in geometrical, as the distance below the surface increases
+in arithmetical proportion. The shock of the waves is received several
+thousand times in the course of twenty-four hours, and hence the sum of
+impulse which the breakwater resists in one stormy day amounts to many
+thousands of millions of tons. The breakwater is entirely an artificial
+construction. If then man could accumulate and control the forces which
+he is able effectually to resist, he might be said to be, physically
+speaking, omnipotent.
+
+[32] Some well known experiments show that it is quite possible to
+accumulate the solar heat by a simple apparatus, and thus to obtain a
+temperature which might be economically important even in the climate of
+Switzerland. Saussure, by receiving the sun's rays in a nest of boxes
+blackened within and covered with glass, raised a thermometer enclosed
+in the inner box to the boiling point; and under the more powerful sun
+of the cape of Good Hope, Sir John Herschel cooked the materials for a
+family dinner by a similar process, using, however, but a single box,
+surrounded with dry sand and covered with two glasses. Why should not so
+easy a method of economizing fuel be resorted to in Italy, and even in
+more northerly climates?
+
+The unfortunate John Davidson records in his journal that he saved fuel
+in Morocco by exposing his teakettle to the sun on the roof of his
+house, where the water rose to the temperature of one hundred and forty
+degrees, and, of course, needed little fire to bring it to boil. But
+this was the direct and simple, not the accumulated heat of the sun.
+
+[33] In the successive stages of social progress, the most destructive
+periods of human action upon nature are the pastoral condition, and that
+of incipient stationary civilization, or, in the newly discovered
+countries of modern geography, the colonial, which corresponds to the
+era of early civilization in older lands. In more advanced states of
+culture, conservative influences make themselves felt; and if highly
+civilized communities do not always restore the works of nature, they at
+least use a less wasteful expenditure than their predecessors in
+consuming them.
+
+[34] The character of geological formation is an element of very great
+importance in determining the amount of erosion produced by running
+water, and, of course, in measuring the consequences of clearing off the
+forests. The soil of the French Alps yields very readily to the force of
+currents, and the declivities of the northern Apennines are covered with
+earth which becomes itself a fluid when saturated with water. Hence the
+erosion of such surfaces is vastly greater than on many other mountains
+of equal steepness of inclination. This point is fully considered by the
+authors referred to in chap. iii, _post_.
+
+[35] The Travels of Dr. Dwight, president of Yale College, which embody
+the results of his personal observations, and of his inquiries among the
+early settlers, in his vacation excursions in the Northern States of the
+American Union, though presenting few instrumental measurements or
+tabulated results, are of value for the powers of observation they
+exhibit, and for the sound common sense with which many natural
+phenomena, such for instance as the formation of the river meadows,
+called "intervales," in New England, are explained. They present a true
+and interesting picture of physical conditions, many of which have long
+ceased to exist in the theatre of his researches, and of which few other
+records are extant.
+
+[36] The general law of temperature is that it decreases as we ascend.
+But, in hilly regions, the law is reversed in cold, still weather, the
+cold air descending, by reason of its greater gravity, into the valleys.
+If there be wind enough, however, to produce a disturbance and
+intermixture of higher and lower atmospheric strata, this exception to
+the general law does not take place. These facts have long been familiar
+to the common people of Switzerland and of New England, but their
+importance has not been sufficiently taken into account in the
+discussion of meteorological observations. The descent of the cold air
+and the rise of the warm affect the relative temperatures of hills and
+valleys to a much greater extent than has been usually supposed. A
+gentleman well known to me kept a thermometrical record for nearly half
+a century, in a New England country town, at an elevation of at least
+1,500 feet above the sea. During these years his thermometer never fell
+lower than 26 deg. Fahrenheit, while at the shire town of the county,
+situated in a basin one thousand feet lower, and ten miles distant, as
+well as at other points in similar positions, the mercury froze several
+times in the same period.
+
+[37] Railroad surveys must be received with great caution where any
+motive exists for _cooking_ them. Capitalists are shy of investments in
+roads with steep grades, and of course it is important to make a fair
+show of facilities in obtaining funds for new routes. Joint-stock
+companies have no souls; their managers, in general, no consciences.
+Cases can be cited where engineers and directors of railroads, with long
+grades above one hundred feet to the mile, have regularly sworn in their
+annual reports, for years in succession, that there were no grades upon
+their routes exceeding half that elevation. In fact, every person
+conversant with the history of these enterprises knows that in their
+public statements falsehood is the rule, truth the exception.
+
+What I am about to remark is not exactly relevant to my subject; but it
+is hard to "get the floor" in the world's great debating society, and
+when a speaker who has anything to say once finds access to the public
+ear, he must make the most of his opportunity, without inquiring too
+nicely whether his observations are "in order." I shall harm no honest
+man by endeavoring, as I have often done elsewhere, to excite the
+attention of thinking and conscientious men to the dangers which
+threaten the great moral and even political interests of Christendom,
+from the unscrupulousness of the private associations that now control
+the monetary affairs, and regulate the transit of persons and property,
+in almost every civilized country. More than one American State is
+literally governed by unprincipled corporations, which not only defy the
+legislative power, but have, too often, corrupted even the
+administration of justice. Similar evils have become almost equally rife
+in England, and on the Continent; and I believe the decay of commercial
+morality, and indeed of the sense of all higher obligations than those
+of a pecuniary nature, on both sides of the Atlantic, is to be ascribed
+more to the influence of joint-stock banks and manufacturing and railway
+companies, to the workings, in short, of what is called the principle of
+"associate action," than to any other one cause of demoralization.
+
+The apophthegm, "the world is governed too much," though unhappily too
+truly spoken of many countries--and perhaps, in some aspects, true of
+all--has done much mischief whenever it has been too unconditionally
+accepted as a political axiom. The popular apprehension of being
+over-governed, and, I am afraid, more emphatically the fear of being
+over-taxed, has had much to do with the general abandonment of certain
+governmental duties by the ruling powers of most modern states. It is
+theoretically the duty of government to provide all those public
+facilities of intercommunication and commerce, which are essential to
+the prosperity of civilized commonwealths, but which individual means
+are inadequate to furnish, and for the due administration of which
+individual guaranties are insufficient. Hence public roads, canals,
+railroads, postal communications, the circulating medium of exchange,
+whether metallic or representative, armies, navies, being all matters in
+which the nation at large has a vastly deeper interest than any private
+association can have, ought legitimately to be constructed and provided
+only by that which is the visible personification and embodiment of the
+nation, namely, its legislative head. No doubt the organization and
+management of these institutions by government are liable, as are all
+things human, to great abuses. The multiplication of public
+placeholders, which they imply, is a serious evil. But the corruption
+thus engendered, foul as it is, does not strike so deep as the
+rottenness of private corporations; and official rank, position, and
+duty have, in practice, proved better securities for fidelity and
+pecuniary integrity in the conduct of the interests in question, than
+the suretyships of private corporate agents, whose bondsmen so often
+fail or abscond before their principal is detected.
+
+Many theoretical statesmen have thought that voluntary associations for
+strictly pecuniary and industrial purposes, and for the construction and
+control of public works, might furnish, in democratic countries, a
+compensation for the small and doubtful advantages, and at the same time
+secure an exemption from the great and certain evils, of aristocratic
+institutions. The example of the American States shows that private
+corporations--whose rule of action is the interest of the association,
+not the conscience of the individual--though composed of
+ultra-democratic elements, may become most dangerous enemies to rational
+liberty, to the moral interests of the commonwealth, to the purity of
+legislation and of judicial action, and to the sacredness of private
+rights.
+
+[38] It is impossible to say how far the abstraction of water from the
+earth by broad-leaved field and garden plants--such as maize, the gourd
+family, the cabbage, &c.--is compensated by the condensation of dew,
+which sometimes pours from them in a stream, by the exhalation of
+aqueous vapor from their leaves, which is directly absorbed by the
+ground, and by the shelter they afford the soil from sun and wind, thus
+preventing evaporation. American farmers often say that after the leaves
+of Indian corn are large enough to "shade the ground," there is little
+danger that the plants will suffer from drought; but it is probable that
+the comparative security of the fields from this evil is in part due to
+the fact that, at this period of growth, the roots penetrate down to a
+permanently humid stratum of soil, and draw from it the moisture they
+require. Stirring the ground between the rows of maize with a light
+harrow or cultivator, in very dry seasons, is often recommended as a
+preventive of injury by drought. It would seem, indeed, that loosening
+and turning over the surface earth might aggravate the evil by promoting
+the evaporation of the little remaining moisture; but the practice is
+founded partly on the belief that the hygroscopicity of the soil is
+increased by it to such a degree that it gains more by absorption than
+it loses by evaporation, and partly on the doctrine that to admit air to
+the rootlets, or at least to the earth near them, is to supply directly
+elements of vegetable growth.
+
+[39] The vine-wood planks of the ancient great door of the cathedral at
+Ravenna, which measured thirteen feet in length by a foot and a quarter
+in width, are traditionally said to have been brought from the Black
+Sea, by way of Constantinople, about the eleventh or twelfth century. No
+vines of such dimensions are now found in any other part of the East,
+and, though I have taken some pains on the subject, I never found in
+Syria or in Turkey a vine stock exceeding six inches in diameter, bark
+excluded.
+
+[40] The Northmen who--as I think it has been indisputably established
+by Professor Rafn of Copenhagen--visited the coast of Massachusetts
+about the year 1000, found grapes growing there in profusion, and the
+vine still flourishes in great variety and abundance in the southeastern
+counties of that State. The townships in the vicinity of the Dighton
+rock, supposed by many--with whom, however, I am sorry I cannot
+agree--to bear a Scandinavian inscription, abound in wild vines, and I
+have never seen a region which produced them so freely. I have no doubt
+that the cultivation of the grape will become, at no distant day, one of
+the most important branches of rural industry in that district.
+
+[41] _Les Etats Unis d'Amerique en 1863_, p. 360. By "improved" land, in
+the reports on the census of the United States, is meant "cleared land
+used for grazing, grass, or tillage, or which is now fallow, connected
+with or belonging to a farm."--_Instructions to Marshals and Assistants,
+Census of 1850_, schedule 4, Sec.Sec. 2, 3.
+
+[42] Cotton, though cultivated in Asia and Africa from the remotest
+antiquity, and known as a rare and costly product to the Latins and the
+Greeks, was not used by them to any considerable extent, nor did it
+enter into their commerce as a regular article of importation. The early
+voyagers found it in common use in the West Indies and in the provinces
+first colonized by the Spaniards; but it was introduced into the
+territory of the United States by European settlers, and did not become
+of any importance until after the Revolution. Cotton seed was sown in
+Virginia as early as 1621, but was not cultivated with a view to profit
+for more than a century afterward. Sea-island cotton was first grown on
+the coast of Georgia in 1786, the seed having been brought from the
+Bahamas, where it had been introduced from Anguilla.--BIGELOW, _Les
+Etats Unis en 1863_, p. 370.
+
+[43] The sugar cane was introduced by the Arabs into Sicily and Spain as
+early as the ninth century, and though it is now scarcely grown in those
+localities, I am not aware of any reason to doubt that its cultivation
+might be revived with advantage. From Spain it was carried to the West
+Indies, though different varieties have since been introduced into those
+islands from other sources. Tea is now cultivated with a certain success
+in Brazil, and promises to become an important crop in the Southern
+States of the American Union. The lemon is, I think, readily
+recognizable, by Pliny's description, as known to the ancients, but it
+does not satisfactorily appear that they were acquainted with the
+orange.
+
+[44] John Smith mentions, in his _Historie of Virginia_, 1624, pease and
+beans as having been cultivated by the natives before the arrival of the
+whites, and there is no doubt, I believe, that the pumpkin and several
+other cucurbitaceous plants are of American origin; but most, if not all
+the varieties of pease, beans, and other pod fruits now grown in
+American gardens, are from European and other foreign seed. See
+_Appendix_, No, 8.
+
+[45] There are some usages of polite society which are inherently low in
+themselves, and debasing in their influence and tendency, and which no
+custom or fashion can make respectable or fit to be followed by
+self-respecting persons. It is essentially vulgar to smoke or chew
+tobacco, and especially to take snuff; it is unbecoming a gentleman, to
+perform the duties of his coachman; it is indelicate in a lady to wear
+in the street skirts so long that she cannot walk without grossly
+soiling them. Not that all these things are not practised by persons
+justly regarded as gentlemen and ladies; but the same individuals would
+be, and feel themselves to be, much more emphatically gentlemen and
+ladies, if they abstained from them.
+
+[46] The name _portogallo_, so generally applied to the orange in Italy,
+seems to favor this claim. The orange, however, was known in Europe
+before the discovery of the Cape of Good Hope, and, therefore, before
+the establishment of direct relations between Portugal and the East.
+
+A correspondent of the _Athenaeum_, in describing the newly excavated
+villa, which has been named Livia's Villa, near the Porta del Popolo at
+Rome, states that: "The walls of one of the rooms are, singularly
+enough, decorated with landscape paintings, a grove of palm and _orange_
+trees, with fruits and birds on the branches--the colors all as fresh
+and lively as if painted yesterday." The writer remarks on the character
+of this decoration as something very unusual in Roman architecture; and
+if the trees in question are really orange, and not lemon trees, this
+circumstance may throw some doubt on the antiquity of the painting. If,
+on the other hand, it proves really ancient, it shows that the orange
+was known to the Roman painters, if not gardeners. The landscape may
+perhaps represent Oriental, not European scenery. The accessories of the
+picture would probably determine that question.--_Athenaeum_, No. 1859,
+June 13, 1863.
+
+MUeLLER, _Das Buch der Pflanzenwelt_, p. 86, asserts that in 1802 the
+ancestor of all the mulberries in France, planted in 1500, was still
+standing in a garden in the village of Allan-Montelimart.
+
+[47] The vegetables which, so far as we know their history, seem to have
+been longest the objects of human care, can, by painstaking industry, be
+made to grow under a great variety of circumstances, and some of
+them--the vine for instance--prosper nearly equally well, when planted
+and tended, on soils of almost any geological character; but their seeds
+vegetate only in artificially prepared ground, they have little
+self-sustaining power, and they soon perish when the nursing hand of man
+is withdrawn from them. In range of climate, wild plants are much more
+limited than domestic, but much less so with regard to the state of the
+soil in which they germinate and grow. See _Appendix_, No. 9.
+
+Dr. Dwight remarks that the seeds of American forest trees will not
+vegetate when dropped on grassland. This is one of the very few errors
+of personal observation to be found in that author's writings. There are
+seasons, indeed, when few tree seeds germinate in the meadows and the
+pastures, and years favorable to one species are not always propitious
+to another; but there is no American forest tree known to me which does
+not readily propagate itself by seed in the thickest greensward, if its
+germs are not disturbed by man or animals.
+
+[48] Some years ago I made a collection of weeds in the wheatfields of
+Upper Egypt, and another in the gardens on the Bosphorus. Nearly all the
+plants were identical with those which grow under the same conditions in
+New England. I do not remember to have seen in America the scarlet wild
+poppy so common in European grainfields. I have heard, however, that it
+has lately crossed the Atlantic, and I am not sorry for it. With our
+abundant harvests of wheat, we can well afford to pay now and then a
+loaf of bread for the cheerful radiance of this brilliant flower.
+
+[49] Josselyn, who wrote about fifty years after the foundation of the
+first British colony in New England, says that the settlers at Plymouth
+had observed more than twenty English plants springing up spontaneously
+near their improvements.
+
+Every country has many plants not now, if ever, made use of by man, and
+therefore not designedly propagated by him, but which cluster around his
+dwelling, and continue to grow luxuriantly on the ruins of his rural
+habitation after he has abandoned it. The site of a cottage, the very
+foundation stones of which have been carried off, may often be
+recognized, years afterward, by the rank weeds which cover it, though no
+others of the same species are found for miles.
+
+"Mediaeval Catholicism," says Vaupell, "brought us the red
+horsehoof--whose reddish-brown flower buds shoot up from the ground when
+the snow melts, and are followed by the large leaves--_laegekulsukker_
+and snake-root, which grow only where there were convents and other
+dwellings in the Middle Ages."--_Boegens Indvandring i de Danske Skove_,
+pp. 1, 2.
+
+[50] VAUPELL, _Boegens Indvandring i de Danske Skove_, p. 2.
+
+[51] It is, I believe, nearly certain that the Turks inflicted tobacco
+upon Hungary, and probable that they in some measure compensated the
+injury by introducing maize also, which, as well as tobacco, has been
+claimed as Hungarian by patriotic Magyars.
+
+[52] Accidents sometimes limit, as well as promote, the propagation of
+foreign vegetables in countries new to them. The Lombardy poplar is a
+di[oe]cious tree, and is very easily grown from cuttings. In most of the
+countries into which it has been introduced the cuttings have been taken
+from the male, and as, consequently, males only have grown from them,
+the poplar does not produce seed in those regions. This is a fortunate
+circumstance, for otherwise this most worthless and least ornamental of
+trees would spread with a rapidity that would make it an annoyance to
+the agriculturist. See _Appendix_, No. 10.
+
+[53] Tempests, violent enough to destroy all cultivated plants, often
+spare those of spontaneous growth. During the present summer, I have
+seen in Northern Italy, vineyards, maize fields, mulberry and fruit
+trees completely stripped of their foliage by hail, while the forest
+trees scattered through the meadows, and the shrubs and brambles which
+sprang up by the wayside, passed through the ordeal with scarcely the
+loss of a leaflet.
+
+[54] The boar spear is provided with a short crossbar, to enable the
+hunter to keep the infuriated animal at bay after he has transfixed him.
+
+[55] Some botanists think that a species of water lily represented in
+many Egyptian tombs has become extinct, and the papyrus, which must have
+once been abundant in Egypt, is now found only in a very few localities
+near the mouth of the Nile. It grows very well and ripens its seeds in
+the waters of the Anapus near Syracuse, and I have seen it in garden
+ponds at Messina and in Malta. There is no apparent reason for believing
+that it could not be easily cultivated in Egypt, to any extent, if there
+were any special motive for encouraging its growth.
+
+[56] Although it is not known that man has extirpated any vegetable, the
+mysterious diseases which have, for the last twenty years, so
+injuriously affected the potato, the vine, the orange, the olive, and
+silk husbandry--whether in this case the malady resides in the mulberry
+or in the insect--are ascribed by some to a climatic deterioration
+produced by excessive destruction of the woods. As will be seen in the
+next chapter, a retardation in the period of spring has been observed in
+numerous localities in Southern Europe, as well as in the United States.
+This change has been thought to favor the multiplication of the obscure
+parasites which cause the injury to the vegetables just mentioned.
+
+Babinet supposes the parasites which attack the grape and the potato to
+be animal, not vegetable, and he ascribes their multiplication to
+excessive manuring and stimulation of the growth of the plants on which
+they live. They are now generally, if not universally, regarded as
+vegetable, and if they are so, Babinet's theory would be even more
+plausible than on his own supposition.--_Etudes et Lectures_, ii, p.
+269.
+
+It is a fact of some interest in agricultural economy, that the oidium,
+which is so destructive to the grape, has produced no pecuniary loss to
+the proprietors of the vineyards in France. "The price of wine," says
+Lavergne, "has quintupled, and as the product of the vintage has not
+diminished in the same proportion, the crisis has been, on the whole,
+rather advantageous than detrimental to the country."--_Economie Rurale
+de la France_, pp. 263, 264.
+
+France produces a considerable surplus of wines for exportation, and the
+sales to foreign consumers are the principal source of profit to French
+vinegrowers. In Northern Italy, on the contrary, which exports little
+wine, there has been no such increase in the price of wine as to
+compensate the great diminution in the yield of the vines, and the loss
+of this harvest is severely felt. In Sicily, however, which exports much
+wine, prices have risen as rapidly as in France. Waltershausen informs
+us that in the years 1838-'42, the red wine of Mount Etna sold at the
+rate of one kreuzer and a half, or one cent the bottle, and sometimes
+even at but two thirds that price, but that at present it commands five
+or six times as much.
+
+The grape disease has operated severely on small cultivators whose
+vineyards only furnished a supply for domestic use, but Sicily has
+received a compensation in the immense increase which it has occasioned
+in both the product and the profits of the sulphur mines. Flour of
+sulphur is applied to the vine as a remedy against the disease, and the
+operation is repeated from two to three or four--and even, it is said,
+eight or ten times--in a season. Hence there is a great demand for
+sulphur in all the vine-growing countries of Europe, and Waltershausen
+estimates the annual consumption of that mineral for this single purpose
+at 850,000 _centner_, or more than forty thousand tons. The price of
+sulphur has risen in about the same proportion as that of
+wine.--WALTERSHAUSEN, _Ueber den Sicilianischen Ackerbau_, pp. 19, 20.
+
+[57] Some recent observations of the learned traveller Wetzstein are
+worthy of special notice. "The soil of the Hauran," he remarks,
+"produces, in its primitive condition, much wild rye, which is not known
+as a cultivated plant in Syria, and much wild barley and oats. These
+cereals precisely resemble the corresponding cultivated plants in leaf,
+ear, size, and height of straw, but their grains are sensibly flatter
+and poorer in flour."--_Reisebericht ueber Hauran und die Trachonen_, p.
+40.
+
+[58] This remark is much less applicable to fruit trees than to garden
+vegetables and the cerealia. The wild orange of Florida, though once
+considered indigenous, is now generally thought by botanists to be
+descended from the European orange introduced by the early colonists.
+The fig and the olive are found growing wild in every country where
+those trees are cultivated. The wild fig differs from the domesticated
+in its habits, its season of fructification, and its insect population,
+but is, I believe, not specifically distinguishable from the garden fig,
+though I do not know that it is reclaimable by cultivation. The wild
+olive, which is so abundant in the Tuscan Maremma, produces good fruit
+without further care, when thinned out and freed from the shade of other
+trees, and is particularly suited for grafting. See SALVAGNOLI, _Memorie
+sulle Maremme_, pp. 63-73. See _Appendix_, No. 12.
+
+FRAAS, _Klima und Pflanzenwelt in der Zeit_, pp. 35-38, gives, upon the
+authority of Link and other botanical writers, a list of the native
+habitats of most cereals and of many fruits, or at least of localities
+where these plants are said to be now found wild; but the data do not
+appear to rest, in general, upon very trustworthy evidence.
+Theoretically, there can be little doubt that all our cultivated plants
+are modified forms of spontaneous vegetation, but the connection is not
+historically shown, nor are we able to say that the originals of some
+domesticated vegetables may not be now extinct and unrepresented in the
+existing wild flora. See, on this subject, HUMBOLDT, _Ansichten der
+Natur_, i, pp. 208, 209. The following are interesting incidents: "A
+negro slave of the great Cortez was the first who sowed wheat in New
+Spain. He found three grains of it among the rice which had been brought
+from Spain as food for the soldiers. In the Franciscan monastery at
+Quito, I saw the earthen pot which contained the first wheat sown there
+by Friar Jodoco Rixi, of Ghent. It was preserved as a relic."
+
+The Adams of modern botany and zoology have been put to hard shifts in
+finding names for the multiplied organisms which the Creator has brought
+before them, "to see what they would call them;" and naturalists and
+philosophers have shown much moral courage in setting at naught the laws
+of philology in the coinage of uncouth words to express scientific
+ideas. It is much to be wished that some bold neologist would devise
+English technical equivalents for the German _verwildert_, run-wild, and
+_veredelt_, improved by cultivation.
+
+[59] Could the bones and other relics of the domestic quadrupeds
+destroyed by disease or slaughtered for human use in civilized countries
+be collected into large deposits, as obscure causes have gathered
+together those of extinct animals, they would soon form aggregations
+which might almost be called mountains. There were in the United States,
+in 1860, as we shall see hereafter, nearly one hundred and two millions
+of horses, black cattle, sheep, and swine. There are great numbers of
+all the same animals in the British American Provinces, and in Mexico,
+and there are large herds of wild horses on the plains, and of tamed
+among the independent Indian tribes of North America. It would perhaps
+not be extravagant to suppose that all those cattle may amount to two
+thirds as many as those of the United States, and thus we have in North
+America a total of 170,000,000 domestic quadrupeds belonging to species
+introduced by European colonization, besides dogs, cats, and other
+four-footed household pets and pests, also of foreign origin.
+
+If we allow half a solid foot to the skeleton and other slowly
+destructible parts of each animal, the remains of these herds would form
+a cubical mass measuring not much short of four hundred and fifty feet
+to the side, or a pyramid equal in dimensions to that of Cheops, and as
+the average life of these animals does not exceed six or seven years,
+the accumulations of their bones, horns, hoofs, and other durable
+remains would amount to at least fifteen times as great a volume in a
+single century. It is true that the actual mass of solid matter, left by
+the decay of dead domestic quadrupeds and permanently added to the crust
+of the earth, is not so great as this calculation makes it. The greatest
+proportion of the soft parts of domestic animals, and even of the bones,
+is soon decomposed, through direct consumption by man and other
+carnivora, industrial use, and employment as manure, and enters into new
+combinations in which its animal origin is scarcely traceable; there is,
+nevertheless, a large annual residuum, which, like decayed vegetable
+matter, becomes a part of the superficial mould; and in any event, brute
+life immensely changes the form and character of the superficial strata,
+if it does not sensibly augment the quantity of the matter composing
+them.
+
+The remains of man, too, add to the earthy coating that covers the face
+of the globe. The human bodies deposited in the catacombs during the
+long, long ages of Egyptian history, would perhaps build as large a pile
+as one generation of the quadrupeds of the United States. In the
+barbarous days of old Moslem warfare, the conquerors erected large
+pyramids of human skulls. The soil of cemeteries in the great cities of
+Europe has sometimes been raised several feet by the deposit of the dead
+during a few generations. In the East, Turks and Christians alike bury
+bodies but a couple of feet beneath the surface. The grave is respected
+as long as the tombstone remains, but the sepultures of the ignoble
+poor, and of those whose monuments time or accident has removed, are
+opened again and again to receive fresh occupants. Hence the ground in
+Oriental cemeteries is pervaded with relics of humanity, if not wholly
+composed of them; and an examination of the soil of the lower part of
+the _Petit Champ des Morts_ at Pera, by the naked eye alone, shows the
+observer that it consists almost exclusively of the comminuted bones of
+his fellow man.
+
+[60] It is asserted that the bones of mammoths and mastodons, in many
+instances, appear to have been grazed or cut by flint arrow-heads or
+other stone weapons. These accounts have often been discredited, because
+it has been assumed that the extinction of these animals was more
+ancient than the existence of man. Recent discoveries render it highly
+probable, if not certain, that this conclusion has been too hastily
+adopted. Lyell observes: "These stories * * must in future be more
+carefully inquired into, for we can scarcely doubt that the mastodon in
+North America lived down to a period when the mammoth coexisted with man
+in Europe."--_Antiquity of Man_, p. 354.
+
+On page 143 of the volume just quoted, the same very distinguished
+writer remarks that man "no doubt played his part in hastening the era
+of the extinction" of the large pachyderms and beasts of prey; but, as
+contemporaneous species of other animals, which man cannot be supposed,
+to have extirpated, have also become extinct, he argues that the
+disappearance of the quadrupeds in question cannot be ascribed to human
+action alone.
+
+On this point it may be observed that, as we cannot know what precise
+physical conditions were necessary to the existence of a given extinct
+organism, we cannot say how far such conditions may have been modified
+by the action of man, and he may therefore have influenced the life of
+such organisms in ways, and to an extent, of which we can form no just
+idea.
+
+[61] Evelyn thought the depasturing of grass by cattle serviceable to
+its growth. "The biting of cattle," he remarks, "gives a gentle
+loosening to the roots of the herbage, and makes it to grow fine and
+sweet, and their very breath and treading as well as soil, and the
+comfort of their warm bodies, is wholesome and marvellously
+cherishing."--_Terra, or Philosophical Discourse of Earth_, p. 36.
+
+In a note upon this passage, Hunter observes: "Nice farmers consider the
+lying of a beast upon the ground, for one night only, as a sufficient
+tilth for the year. The breath of graminivorous quadrupeds does
+certainly enrich the roots of grass; a circumstance worthy of the
+attention of the philosophical farmer."--_Terra_, same page.
+
+The "philosophical farmer" of the present day will not adopt these
+opinions without some qualification.
+
+[62] The rat and the mouse, though not voluntarily transported, are
+passengers by every ship that sails from Europe to a foreign port, and
+several species of these quadrupeds have, consequently, much extended
+their range and increased their numbers in modern times. From a story of
+Heliogabalus related by Lampridius, _Hist. Aug. Scriptores_, ed.
+Casaubon, 1690, p. 110, it would seem that mice at least were not very
+common in ancient Rome. Among the capricious freaks of that emperor, it
+is said that he undertook to investigate the statistics of the arachnoid
+population of the capital, and that 10,000 pounds of spiders (or
+spiders' webs--for aranea is equivocal) were readily collected; but when
+he got up a mouse show, he thought ten thousand mice a very fair number.
+I believe as many might almost be found in a single palace in modern
+Rome. Rats are not less numerous in all great cities, and in Paris,
+where their skins are used for gloves, and their flesh, it is whispered,
+in some very complex and equivocal dishes, they are caught by legions. I
+have read of a manufacturer who contracted to buy of the rat catchers,
+at a high price, all the rat skins they could furnish before a certain
+date, and failed, within a week, for want of capital, when the stock of
+peltry had run up to 600,000.
+
+[63] BIGELOW, _Les Etats Unis en_ 1863, pp. 379, 380. In the same
+paragraph this volume states the number of animals slaughtered in the
+United States by butchers, in 1859, at 212,871,653. This is an error of
+the press. Number is confounded with value. A reference to the tables of
+the census shows that the animals slaughtered that year were estimated
+at 212,871,653 _dollars_; the number of head is not given. The wild
+horses and horned cattle of the prairies and the horses of the Indians
+are not included in the returns.
+
+[64] Of this total number, 2,240,000, or nearly nine per cent., are
+reported as working oxen. This would strike European, and especially
+English agriculturists, as a large proportion; but it is explained by
+the difference between a new country and an old, in the conditions which
+determine the employment of animal labor. Oxen are very generally used
+in the United States and Canada for hauling timber and firewood through
+and from the forests; for ploughing in ground still full of rocks,
+stumps, and roots; for breaking up the new soil of the prairies with its
+strong matting of native grasses, and for the transportation of heavy
+loads over the rough roads of the interior. In all these cases, the
+frequent obstructions to the passage of the timber, the plough, and the
+sled or cart, are a source of constant danger to the animals, the
+vehicles, and the harness, and the slow and steady step of the ox is
+attended with much less risk than the swift and sudden movements of the
+impatient horse. It is surprising to see the sagacity with which the
+dull and clumsy ox--hampered as he is by the rigid yoke, the most absurd
+implement of draught ever contrived by man--picks his way, when once
+trained to forest work, among rocks and roots, and even climbs over
+fallen trees, not only moving safely, but drawing timber over ground
+wholly impracticable for the light and agile horse.
+
+Cows, so constantly employed for draught in Italy, are never yoked or
+otherwise used for labor in America, except in the Slave States.
+
+[65] "About five miles from camp we ascended to the top of a high hill,
+and for a great distance ahead every square mile seemed to have a herd
+of buffalo upon it. Their number was variously estimated by the members
+of the party; by some as high as half a million. I do not think it any
+exaggeration to set it down at 200,000."--STEVENS'S _Narrative and Final
+Report. Reports of Explorations and Surveys for Railroad to Pacific_,
+vol. xii, book i, 1860.
+
+The next day, the party fell in with a "buffalo trail," where at least
+100,000 were thought to have crossed a slough.
+
+[66] The most zealous and successful New England hunter of whom I have
+any personal knowledge, and who continued to indulge his favorite
+passion much beyond the age which generally terminates exploits in
+woodcraft, lamented on his deathbed that he had not lived long enough to
+carry up the record of his slaughtered deer to the number of one
+thousand, which he had fixed as the limit of his ambition. He was able
+to handle the rifle, for sixty years, at a period when the game was
+still nearly as abundant as ever, but had killed only nine hundred and
+sixty of these quadrupeds, of all species. The exploits of this Nimrod
+have been far exceeded by prairie hunters, but I doubt whether, in the
+originally wooded territory of the Union, any single marksman has
+brought down a larger number.
+
+[67] _Erdkunde_, viii. _Asien, 1ste Abtheilung_, pp. 660, 758.
+
+[68] See chapter iii, _post_; also HUMBOLDT, _Ansichten der Natur_, i,
+p. 71. From the anatomical character of the bones of the urus, or
+auerochs, found among the relics of the lacustrine population of ancient
+Switzerland, and from other circumstances, it is inferred that this
+animal had been domesticated by that people; and it is stated, I know
+not upon what authority, in _Le Alpi che cingono l'Italia_, that it had
+been tamed by the Veneti also. See LYELL, _Antiquity of Man_, pp. 24,
+25, and the last-named work, p. 489. This is a fact of much interest,
+because it is, I believe, the only known instance of the extinction of a
+domestic quadruped, and the extreme improbability of such an event gives
+some countenance to the theory of the identity of the domestic ox with,
+and its descent from, the urus.
+
+[69] In maintaining the recent existence of the lion in the countries
+named in the text, naturalists have, perhaps, laid too much weight on
+the frequent occurrence of representations of this animal in sculptures
+apparently of a historical character. It will not do to argue, twenty
+centuries hence, that the lion and the unicorn were common in Great
+Britain in Queen Victoria's time, because they are often seen "fighting
+for the crown" in the carvings and paintings of that period.
+
+[70]
+
+ Dar nach sloger schiere, einen wisent bat elch.
+ Starcher bore biere. but einen grimmen schelch.
+ _XVI Auentiure._
+
+The testimony of the _Nibelungen-Lied_ is not conclusive evidence that
+these quadrupeds existed in Germany at the time of the composition of
+that poem. It proves too much; for, a few lines above those just quoted,
+Sigfrid is said to have killed a lion, an animal which the most
+patriotic Teuton will hardly claim as a denizen of mediaeval Germany.
+
+[71] The wild turkey takes readily to the water, and is able to cross
+rivers of very considerable width by swimming. By way of giving me an
+idea of the former abundance of this bird, an old and highly respectable
+gentleman who was among the early white settlers of the West, told me
+that he once counted, in walking down the northern bank of the Ohio
+River, within a distance of four miles, eighty-four turkeys as they
+landed singly, or at most in pairs, after swimming over from the
+Kentucky side.
+
+[72] The wood pigeon has been observed to increase in numbers in Europe
+also, when pains have been taken to exterminate the hawk. The pigeons,
+which migrated in flocks so numerous that they were whole days in
+passing a given point, were no doubt injurious to the grain, but
+probably less so than is generally supposed; for they did not confine
+themselves exclusively to the harvests for their nourishment.
+
+[73] Pigeons were shot near Albany, in New York, a few years ago, with
+green rice in their crops, which it was thought must have been growing,
+a very few hours before, at the distance of seven or eight hundred
+miles.
+
+[74] Professor Treadwell, of Massachusetts, found that a half-grown
+American robin in confinement ate in one day sixty-eight earthworms,
+weighing together nearly once and a half as much as the bird himself,
+and another had previously starved upon a daily allowance of eight or
+ten worms, or about twenty per cent. of his own weight. The largest of
+these numbers appeared, so far as could be judged by watching parent
+birds of the same species, as they brought food to their young, to be
+much greater than that supplied to them when fed in the nest; for the
+old birds did not return with worms or insects oftener than once in ten
+minutes on an average. If we suppose the parents to hunt for food twelve
+hours in a day, and a nest to contain four young, we should have
+seventy-two worms, or eighteen each, as the daily supply of the brood.
+It is probable enough that some of the food collected by the parents may
+be more nutritious than the earthworms, and consequently that a smaller
+quantity sufficed for the young in the nest than when reared under
+artificial conditions.
+
+The supply required by growing birds is not the measure of their wants
+after they have arrived at maturity, and it is not by any means certain
+that great muscular exertion always increases the demand for
+nourishment, either in the lower animals or in man. The members of the
+English Alpine Club are not distinguished for appetites which would make
+them unwelcome guests to Swiss landlords, and I think every man who has
+had the personal charge of field or railway hands, must have observed
+that laborers who spare their strength the least are not the most
+valiant trencher champions. During the period when imprisonment for debt
+was permitted in New England, persons confined in country jails had no
+specific allowance, and they were commonly fed without stint. I have
+often inquired concerning their diet, and been assured by the jailers
+that their prisoners, who were not provided with work or other means of
+exercise, consumed a considerably larger supply of food than common
+out-door laborers.
+
+[75] I hope Michelet has good authority for this statement, but I am
+unable to confirm it.
+
+[76] Apropos of the sparrow--a single pair of which, according to
+Michelet, p. 315, carries to the nest four thousand and three hundred
+caterpillars or coleoptera in a week--I take from the _Record_, an
+English religious newspaper, of December 15, 1862, the following article
+communicated to a country paper by a person who signs himself "A real
+friend to the farmer:"
+
+"_Crawley Sparrow Club._--The annual dinner took place at the George Inn
+on Wednesday last. The first prize was awarded to Mr. I. Redford, Worth,
+having destroyed within the last year 1,467. Mr. Heayman took the second
+with 1,448 destroyed. Mr. Stone, third, with 982 affixed. Total
+destroyed, 11,944. Old birds, 8,663; young ditto, 722; eggs, 2,556."
+
+This trio of valiant fowlers, and their less fortunate--or rather less
+unfortunate, but not therefore less guilty--associates, have rescued by
+their prowess, it may be, a score of pecks of grain from being devoured
+by the voracious sparrow, but every one of the twelve thousand hatched
+and unhatched birds, thus sacrificed to puerile vanity and ignorant
+prejudice, would have saved his bushel of wheat by preying upon insects
+that destroy the grain. Mr. Redford, Mr. Heayman, and Mr. Stone ought to
+contribute the value of the bread they have wasted to the fund for the
+benefit of the Lancashire weavers; and it is to be hoped that the next
+Byron will satirize the sparrowcide as severely as the first did the
+prince of anglers, Walton, in the well known lines:
+
+ "The quaint, old, cruel coxcomb in his gullet
+ Should have a hook, and a small trout to pull it."
+
+[77] SALVAGNOLI, _Memorie sulle Maremme Toscane_, p. 143. The country
+about Naples is filled with slender towers fifteen or twenty feet high,
+which are a standing puzzle to strangers. They are the stations of the
+fowlers who watch from them the flocks of small birds and drive them
+down in to the nets by throwing stones over them. See _Appendix_, No.
+14.
+
+Tschudi has collected in his little work, _Ueber die
+Landwirthschaftliche Bedeutung der Voegel_, many interesting facts
+respecting the utility of birds, and the wanton destruction of them in
+Italy and elsewhere. Not only the owl, but many other birds more
+familiarly known as predacious in their habits, are useful by destroying
+great numbers of mice and moles. The importance of this last service
+becomes strikingly apparent when it is known that the burrows of the
+mole are among the most frequent causes of rupture in the dikes of the
+Po, and, consequently, of inundations which lay many square miles under
+water.--_Annales des Ponts et Chaussees_, 1847, 1re semestre, p. 150.
+See also VOGT, _Nuetzliche u. schaedliche Thiere_.
+
+[78] Wild birds are very tenacious in their habits. The extension of
+particular branches of agriculture introduces new birds; but unless in
+the case of such changes in physical conditions, particular species seem
+indissolubly attached to particular localities. The migrating tribes
+follow almost undeviatingly the same precise line of flight in their
+annual journeys, and establish themselves in the same breeding places
+from year to year. The stork is a strong-winged bird and roves far for
+food, but very rarely establishes new colonies. He is common in Holland,
+but unknown in England. Not above five or six pairs of storks commonly
+breed in the suburbs of Constantinople along the European shore of the
+narrow Bosphorus, while--much to the satisfaction of the Moslems, who
+are justly proud of the marked partiality of so orthodox a bird--dozens
+of chimneys of the true believers on the Asiatic side are crowned with
+his nests. See _App._ No. 15.
+
+[79] It is not the unfledged and the nursing bird alone that are exposed
+to destruction by severe weather. Whole flocks of adult and
+strong-winged tribes are killed by hail. Severe winters are usually
+followed by a sensible diminution in the numbers of the non-migrating
+birds, and a cold storm in summer often proves fatal to the more
+delicate species. On the 10th of June, 184-, five or six inches of snow
+fell in Northern Vermont. The next morning I found a humming bird killed
+by the cold, and hanging by its claws just below a loose clapboard on
+the wall of a small wooden building where it had sought shelter.
+
+[80] LYELL, _Antiquity of Man_, p. 409, observes: "Of birds it is
+estimated that the number of those which die every year equals the
+aggregate number by which the species to which they respectively belong
+is, on the average, permanently represented."
+
+A remarkable instance of the influence of new circumstances upon birds
+was observed upon the establishment of a lighthouse on Cape Cod some
+years since. The morning after the lamps were lighted for the first
+time, more than a hundred dead birds of several different species,
+chiefly water fowl, were found at the foot of the tower. They had been
+killed in the course of the night by flying against the thick glass or
+grating of the lantern. See _Appendix_, No. 16.
+
+Migrating birds, whether for greater security from eagles, hawks, and
+other enemies, or for some unknown reason, perform a great part of their
+annual journeys by night; and it is observed in the Alps that they
+follow the high roads in their passage across the mountains. This is
+partly because the food in search of which they must sometimes descend
+is principally found near the roads. It is, however, not altogether for
+the sake of consorting with man, or of profiting by his labors, that
+their line of flight conforms to the paths he has traced, but rather
+because the great roads are carried through the natural depressions in
+the chain, and hence the birds can cross the summit by these routes
+without rising to a height where at the seasons of migration the cold
+would be excessive.
+
+The instinct which guides migratory birds in their course is not in all
+cases infallible, and it seems to be confounded by changes in the
+condition of the surface. I am familiar with a village in New England,
+at the junction of two valleys, each drained by a mill stream, where the
+flocks of wild geese which formerly passed, every spring and autumn,
+were very frequently lost, as it was popularly phrased, and I have often
+heard their screams in the night as they flew wildly about in perplexity
+as to the proper course. Perhaps the village lights embarrassed them, or
+perhaps the constant changes in the face of the country, from the
+clearings then going on, introduced into the landscape features not
+according with the ideal map handed down in the anserine family, and
+thus deranged its traditional geography.
+
+[81] The cappercailzie, or tjaeder, as he is called in Sweden, is a bird
+of singular habits, and seems to want some of the protective instincts
+which secure most other wild birds from destruction. The younger
+Laestadius frequently notices the tjaeder, in his very remarkable account
+of the Swedish Laplanders--a work wholly unsurpassed as a genial picture
+of semi-barbarian life, and not inferior in minuteness of detail to
+Schlatter's description of the manners of the Nogai Tartars, or even to
+Lane's admirable and exhaustive work on the Modern Egyptians. The
+tjaeder, though not a bird of passage, is migratory, or rather wandering
+in domicile, and appears to undertake very purposeless and absurd
+journeys. "When he flits," says Laestadius, "he follows a straight
+course, and sometimes pursues it quite out of the country. It is said
+that, in foggy weather, he sometimes flies out to sea, and, when tired,
+falls into the water and is drowned. It is accordingly observed that,
+when he flies westwardly, toward the mountains, he soon comes back
+again; but when he takes an eastwardly course, he returns no more, and
+for a long time is very scarce in Lapland. From this it would seem that
+he turns back from the bald mountains, when he discovers that he has
+strayed from his proper home, the wood; but when he finds himself over
+the Baltic, where he cannot alight to rest and collect himself, he flies
+on until he is exhausted and falls into the sea."--PETRUS LAESTADIUS,
+_Journal af foersta aret, etc._, p. 325.
+
+[82] _Die Herzogthuemer Schleswig und Holstein_, i, p. 203.
+
+[83] Gulls hover about ships in port, and often far out at sea,
+diligently watching for the waste of the caboose. "While the four great
+fleets, English, French, Turkish, and Egyptian, were lying in the
+Bosphorus, in the summer and autumn of 1853, a young lady of my family
+called my attention to the fact that the gulls were far more numerous
+about the ships of one of the fleets than about the others. This was
+verified by repeated observation, and the difference was owing no doubt
+to the greater abundance of the refuse from the cookrooms of the naval
+squadron most frequented by the birds. Persons acquainted with the
+economy of the navies of the states in question, will be able to
+conjecture which fleet was most favored with these delicate attentions.
+
+[84] Birds do not often voluntarily take passage on board ships bound
+for foreign countries, but I can testify to one such case. A stork,
+which had nested near one of the palaces on the Bosphorus, had, by some
+accident, injured a wing, and was unable to join his follows when they
+commenced their winter migration to the banks of the Nile. Before he was
+able to fly again, he was caught, and the flag of the nation to which
+the palace belonged was tied to his leg, so that he was easily
+identified at a considerable distance. As his wing grow stronger, he
+made several unsatisfactory experiments at flight, and at last, by a
+vigorous effort, succeeded in reaching a passing ship bound southward,
+and perched himself on a topsail yard. I happened to witness this
+movement, and observed him quietly maintaining his position as long as I
+could discern him with a spyglass. I suppose he finished the voyage, for
+he certainly did not return to the palace.
+
+[85] The enthusiasm of naturalists is not always proportioned to the
+magnitude or importance of the organisms they concern themselves with.
+It is not recorded that Adams, who found the colossal antediluvian
+pachyderm in a thick-ribbed mountain of Siberian ice, ran wild over his
+_trouvaille_; but Schmidl, in describing the natural history of the
+caves of the Karst, speaks of an eminent entomologist as "_der
+glueckliche Entdecker_," the _happy_ discoverer of a new coleopteron, in
+one of those dim caverns. How various are the sources of happiness!
+Think of a learned German professor, the bare enumeration of whose
+Rath-ships and scientific Mitglied-ships fills a page, made famous in
+the annals of science, immortal, happy, by the discovery of a beetle!
+Had that imperial _ennuye_, who offered a premium for the invention of a
+new pleasure, but read Schmidl's _Hoehlen des Karstes_, what splendid
+rewards would he not have heaped upon Kirby and Spence!
+
+[86] I believe there is no foundation for the supposition that
+earthworms attack the tuber of the potato. Some of them, especially one
+or two species employed by anglers as bait, if natives of the woods, are
+at least rare in shaded grounds, but multiply very rapidly after the
+soil is brought under cultivation. Forty or fifty years ago they were so
+scarce in the newer parts of New England, that the rustic fishermen of
+every village kept secret the few places where they were to be found in
+their neighborhood, as a professional mystery, but at present one can
+hardly turn over a shovelful of rich moist soil anywhere, without
+unearthing several of them. A very intelligent lady, born in the woods
+of Northern New England, told me that, in her childhood, these worms
+were almost unknown in that region, though anxiously sought for by the
+anglers, but that they increased as the country was cleared, and at last
+became so numerous in some places, that the water of springs, and even
+of shallow wells, which had formerly been excellent, was rendered
+undrinkable by the quantity of dead worms that fell into them. The
+increase of the robin and other small birds which follow the settler
+when he has prepared a suitable home for them, at last checked the
+excessive multiplication of the worms, and abated the nuisance.
+
+[87] I have already remarked that the remains of extant animals are
+rarely, if ever, gathered in sufficient quantities to possess any
+geographical importance by their mere mass; but the decayed exuviae of
+even the smaller and humbler forms of life are sometimes abundant enough
+to exercise a perceptible influence on soil and atmosphere. "The plain
+of Cumana," says Humboldt, "presents a remarkable phenomenon, after
+heavy rains. The moistened earth, when heated by the rays of the sun,
+diffuses the musky odor common in the torrid zone to animals of very
+different classes, to the jaguar, the small species of tiger cat, the
+cabiai, the gallinazo vulture, the crocodile, the viper, and the
+rattlesnake. The gaseous emanations, the vehicles of this aroma, appear
+to be disengaged in proportion as the soil, which contains the remains
+of an innumerable multitude of reptiles, worms, and insects, begins to
+be impregnated with water. Wherever we stir the earth, we are struck
+with the mass of organic substances which in turn are developed and
+become transformed or decomposed. Nature in these climes seems more
+active, more prolific, and so to speak, more prodigal of life."
+
+[88] It is remarkable that Palissy, to whose great merits as an acute
+observer I am happy to have frequent occasion to bear testimony, had
+noticed that vegetation was necessary to maintain the purity of water in
+artificial reservoirs, though he mistook the rationale of its influence,
+which he ascribed to the elemental "salt" supposed by him to play an
+important part in all the operations of nature. In his treatise upon
+Waters and Fountains, p. 174, of the reprint of 1844, he says: "And in
+special, thou shalt note one point, the which is understood of few: that
+is to say, that the leaves of the trees which fall upon the parterre,
+and the herbs growing beneath, and singularly the fruits, if any there
+be upon the trees, being decayed, the waters of the parterre shall draw
+unto them the salt of the said fruits, leaves, and herbs, the which
+shall greatly better the water of thy fountains, and hinder the
+putrefaction thereof."
+
+[89] Between the years 1851 and 1853, both inclusive, the United States
+exported 2,665,857 pounds of beeswax, besides a considerable quantity
+employed in the manufacture of candles for exportation. This is an
+average of more than 330,000 pounds per year. The census of 1850 gave
+the total production of wax and honey for that year at 14,853,128
+pounds. In 1860, it amounted to 26,370,813 pounds, the increase being
+partly due to the introduction of improved races of bees from Italy and
+Switzerland.--BIGELOW, _Les Etats Unis en 1863_, p. 376.
+
+[90] A few years ago, a laborer, employed at a North American port in
+discharging a cargo of hides from the opposite extremity of the
+continent, was fatally poisoned by the bite or the sting of an unknown
+insect, which ran out from a hide he was handling.
+
+[91] In many insects, some of the stages of life regularly continue for
+several years, and they may, under peculiar circumstances, be almost
+indefinitely prolonged. Dr. Dwight mentions the following remarkable
+case of this sort, which may be new to many readers: "While I was here
+[at Williamstown, Mass.], Dr. Fitch showed me an insect, about an inch
+in length, of a brown color tinged with orange, with two antennae, not
+unlike a rosebug. This insect came out of a tea table, made of the
+boards of an apple tree." Dr. Dwight examined the table, and found the
+"cavity whence the insect had emerged into the light," to be "about two
+inches in length, nearly horizontal, and inclining upward very little,
+except at the mouth. Between the hole, and the outside of the leaf of
+the table, there were forty grains of the wood." It was supposed that
+the sawyer and the cabinet maker must have removed at least thirteen
+grains more, and the table had been in the possession of its proprietor
+for twenty years.
+
+[92] It does not appear to be quite settled whether the termites of
+France are indigenous or imported. See QUATREFAGES, _Souvenirs d'un
+Naturaliste_, ii, pp. 400, 542, 543.
+
+[93] I have seen the larva of the dragon fly in an aquarium, bite off
+the head of a young fish as long as itself.
+
+[94] Insects and fish--which prey upon and feed each other--are the only
+forms of animal life that are numerous in the native woods, and their
+range is, of course, limited by the extent of the waters. The great
+abundance of the trout, and of other more or less allied genera in the
+lakes of Lapland, seems to be due to the supply of food provided for
+them by the swarms of insects which in the larva state inhabit the
+waters, or, in other stages of their life, are accidentally swept into
+them. All travellers in the north of Europe speak of the gnat and the
+mosquito as very serious drawbacks upon the enjoyments of the summer
+tourist, who visits the head of the Gulf of Bothnia to see the midnight
+sun, and the brothers Laestadius regard them as one of the great plagues
+of sub-Arctic life. "The persecutions of these insects," says Lars Levi
+Laestadius [_Culex pipiens_, _Culex reptans_, and _Culex pulicaris_],
+"leave not a moment's peace, by day or night, to any living creature.
+Not only man, but cattle, and even birds and wild beasts, suffer
+intolerably from their bite." He adds in a note, "I will not affirm that
+they have ever devoured a living man, but many young cattle, such as
+lambs and calves, have been worried out of their lives by them. All the
+people of Lapland declare that young birds are killed by them, and this
+is not improbable, for birds are scarce after seasons when the midge,
+the gnat, and the mosquito are numerous."--_Om Uppodlingar i
+Lappmarken_, p. 50.
+
+Petrus Laestadius makes similar statements in his _Journal foer foersta
+aret_, p. 285.
+
+[95] It is very questionable whether there is any foundation for the
+popular belief in the hostility of swine and of deer to the rattlesnake,
+and careful experiments as to the former quadruped seem to show that the
+supposed enmity is wholly imaginary. Observing that the starlings,
+_stornelli_, which bred in an old tower in Piedmont, carried something
+from their nests and dropped it upon the ground, about as often as they
+brought food to their young, I watched their proceedings, and found
+every day lying near the tower numbers of dead or dying slowworms, and,
+in a few cases, small lizards, which had, in every instance, lost about
+two inches of the tail. This part I believe the starlings gave to their
+nestlings, and threw away the remainder.
+
+[96] Russell denies the existence of poisonous snakes in Northern Syria,
+and states that the last instance of death known to have occurred from
+the bite of a serpent near Aleppo took place a hundred years before his
+time. In Palestine, the climate, the thinness of population, the
+multitude of insects and of lizards, all circumstances, in fact, seem
+very favorable to the multiplication of serpents, but the venomous
+species, at least, are extremely rare, if at all known, in that country.
+I have, however, been assured by persons very familiar with Mount
+Lebanon, that cases of poisoning from the bite of snakes had occurred
+within a few years, near Hasbeiyeh, and at other places on the southern
+declivities of Lebanon and Hermon. In Egypt, on the other hand, the
+cobra, the asp, and the cerastes are as numerous as ever, and are much
+dreaded by all the natives, except the professional snake charmers. See
+_Appendix_, No. 18.
+
+[97] I use _whale_ not in a technical sense, but as a generic term for
+all the large inhabitants of the sea popularly grouped under that name.
+
+[98] From the narrative of Ohther, introduced by King Alfred into his
+translation of Orosius, it is clear that the Northmen pursued the whale
+fishery in the ninth century, and it appears, both from the poem called
+The Whale, in the Codex Exoniensis, and from the dialogue with the
+fisherman in the Colloquies of Aelfric, that the Anglo-Saxons followed
+this dangerous chase at a period not much later. I am not aware of any
+evidence to show that any of the Latin nations engaged in this fishery
+until a century or two afterward, though it may not be easy to disprove
+their earlier participation in it. In mediaeval literature, Latin and
+Romance, very frequent mention is made of a species of vessel called in
+Latin, _baleneria_, _balenerium_, _balenerius_, _balaneria_, etc.; in
+Catalan, _balener_; in French, _balenier_; all of which words occur in
+many other forms. The most obvious etymology of these words would
+suggest the meaning, _whaler_, _baleinier_; but some have supposed that
+the name was descriptive of the great size of the ships, and others have
+referred it to a different root. From the fourteenth century, the word
+occurs oftener, perhaps, in old Catalan, than in any other language; but
+Capmany does not notice the whale fishery as one of the maritime
+pursuits of the very enterprising Catalan people, nor do I find any of
+the products of the whale mentioned in the old Catalan tariffs. The
+_whalebone_ of the mediaeval writers, which is described as very white,
+is doubtless the ivory of the walrus or of the narwhale.
+
+[99] In consequence of the great scarcity of the whale, the use of coal
+gas for illumination, the substitution of other fatty and oleaginous
+substances, such as lard, palm oil, and petroleum, for right-whale oil
+and spermaceti, the whale fishery has rapidly fallen off within a few
+years. The great supply of petroleum, which is much used for lubricating
+machinery as well as for numerous other purposes, has produced a more
+perceptible effect on the whale fishery than any other single
+circumstance. According to Bigelow, _Les Etats Unis en 1863_, p. 346,
+the American whaling fleet was diminished by 29 in 1858, 57 in 1860, 94
+in 1861, and 65 in 1862. The present number of American ships employed
+in that fishery is 353.
+
+[100] The Origin and History of the English Language, &c., pp. 423, 424.
+
+[101] Among the unexpected results of human action, the destruction or
+multiplication of fish, as well as of other animals, is a not unfrequent
+occurrence. I shall have occasion to mention on a following page the
+extermination of the fish in a Swedish river by a flood occasioned by
+the sudden discharge of the waters of a pond. Williams, in his _History
+of Vermont_, i, p. 149, quoted in Thompson's _Natural History of
+Vermont_, p. 142, records a case of the increase of trout from an
+opposite cause. In a pond formed by damming a small stream to obtain
+water power for a sawmill, and covering one thousand acres of primitive
+forest, the increased supply of food brought within reach of the fish
+multiplied them to that degree, that, at the head of the pond, where, in
+the spring, they crowded together in the brook which supplied it, they
+were taken by the hands at pleasure, and swine caught them without
+difficulty. A single sweep of a small scoopnet would bring up half a
+bushel, carts were filled with them as fast as if picked up on dry land,
+and in the fishing season they were commonly sold at a shilling
+(eightpence halfpenny, or about seventeen cents) a bushel. The increase
+in the size of the trout was as remarkable as the multiplication of
+their numbers.
+
+[102] BABINET, _Etudes et Lectures_, ii, pp. 108, 110.
+
+[103] THOMPSON, _Natural History of Vermont_, p. 38, and Appendix,
+p. 13. There is no reason to believe that the seal breeds in Lake
+Champlain, but the individual last taken there must have been some
+weeks, at least, in its waters. It was killed on the ice in the widest
+part of the lake, on the 23d of February, thirteen days after the
+surface was entirely frozen, except the usual small cracks, and a month
+or two after the ice closed at all points north of the place where the
+seal was found.
+
+[104] See page 89, note, _ante_.
+
+[105] According to Hartwig, the United Provinces of Holland had, in
+1618, three thousand herring busses and nine thousand vessels engaged in
+the transport of these fish to market. The whole number of persons
+employed in the Dutch herring fishery was computed at 200,000.
+
+In the latter part of the eighteenth century, this fishery was most
+successfully prosecuted by the Swedes, and in 1781, the town of
+Gottenburg alone exported 136,649 barrels, each containing 1,200
+herrings, making a total of about 164,000,000; but so rapid was the
+exhaustion of the fish, from this keen pursuit, that in 1799 it was
+found necessary to prohibit the exportation of them altogether.--_Das
+Leben des Meeres_, p. 182.
+
+In 1855, the British fisheries produced 900,000 barrels, or enough to
+supply a fish to every human inhabitant of the globe.
+
+On the shores of Long Island Sound, the white fish, a species of herring
+too bony to be easily eaten, is used as manure in very great quantities.
+Ten thousand are employed as a dressing for an acre, and a single net
+has sometimes taken 200,000 in a day.--DWIGHT's _Travels_, ii, pp. 512,
+515.
+
+[106] The indiscriminate hostility of man to inferior forms of animated
+life is little creditable to modern civilization, and it is painful to
+reflect that it becomes keener and more unsparing in proportion to the
+refinement of the race. The savage slays no animal, not even the
+rattlesnake, wantonly; and the Turk, whom we call a barbarian, treats
+the dumb beast as gently as a child. One cannot live many weeks in
+Turkey without witnessing touching instances of the kindness of the
+people to the lower animals, and I have found it very difficult to
+induce even the boys to catch lizards and other reptiles for
+preservation as specimens. See _Appendix_, No. 19.
+
+The fearless confidence in man, so generally manifested by wild animals
+in newly discovered islands, ought to have inspired a gentler treatment
+of them; but a very few years of the relentless pursuit, to which they
+are immediately subjected, suffice to make them as timid as the wildest
+inhabitants of the European forest. This timidity, however, may easily
+be overcome. The squirrels introduced by Mayor Smith into the public
+parks of Boston are so tame as to feed from the hands of passengers, and
+they not unfrequently enter the neighboring houses.
+
+[107] A fact mentioned by Schubert--and which in its causes and many of
+its results corresponds almost precisely with those connected with the
+escape of Barton Pond in Vermont, so well known to geological
+students--is important, as showing that the diminution of the fish in
+rivers exposed to inundations is chiefly to be ascribed to the
+mechanical action of the current, and not mainly, as some have supposed,
+to changes of temperature occasioned by clearing. Our author states
+that, in 1796, a terrible inundation was produced in the Indalself,
+which rises in the Storsjoe in Jemtland, by drawing off into it the
+waters of another lake near Ragunda. The flood destroyed houses and
+fields; much earth was swept into the channel, and the water made turbid
+and muddy; the salmon and the smaller fish forsook the river altogether,
+and never returned. The banks of the river have never regained their
+former solidity, and portions of their soil are still continually
+falling into the water.--_Resa genom Sverge_, ii, p. 51.
+
+[108] WITTWER, _Physikalische Geographie_, p. 142.
+
+[109] To vary the phrase, I make occasional use of _animalcule_, which,
+as a popular designation, embraces all microscopic organisms. The name
+is founded on the now exploded supposition that all of them are
+animated, which was the general belief of naturalists when attention was
+first drawn to them. It was soon discovered that many of them were
+unquestionably vegetable, and there are numerous genera the true
+classification of which is matter of dispute among the ablest observers.
+There are cases in which objects formerly taken for living animalcules
+turn out to be products of the decomposition of matter once animated,
+and it is admitted that neither spontaneous motion nor even apparent
+irritability are sure signs of animal life.
+
+[110] See an interesting report on the coral fishery, by Sant' Agabio,
+Italian Consul-General at Algiers, in the _Bollettino Consolare_,
+published by the Department of Foreign Affairs, 1862, pp. 139, 151, and
+in the _Annali di Agricoltura, Industria e Commercio_, No. ii, pp. 360,
+373.
+
+[111] The fermentation of liquids, and in many cases the decomposition
+of semi-solids, formerly supposed to be owing purely to chemical action,
+are now ascertained to be due to vital processes of living minute
+organisms both vegetable and animal, and consequently to physiological,
+as well as to chemical forces. Even alcohol is stated to be an animal
+product. See an interesting article by Auguste Laugel on the recent
+researches of Pasteur, in the _Revue des Deux Mondes_, for September
+15th, 1863.
+
+[112] The recorded evidence in support of the proposition in the text
+has been collected by L. F. Alfred Maury, in his _Histoire des grandes
+Forets de la Gaule et de l'ancienne France_, and by Becquerel, in his
+important work, _Des climats et de l'Influence qu'exercent les Sols
+boises et non boises_, livre ii, chap. i to iv.
+
+We may rank among historical evidences on this point, if not technically
+among historical records, old geographical names and terminations
+etymologically indicating forest or grove, which are so common in many
+parts of the Eastern Continent now entirely stripped of woods--such as,
+in Southern Europe, Breuil, Broglio, Brolio, Brolo; in Northern, Bruehl,
+-wald, -wold, -wood, -shaw, -skeg, and -skov.
+
+[113] The island of Madeira, whose noble forests were devastated by fire
+not long after its colonization by European settlers, derives its name
+from the Portuguese word for wood.
+
+[114] Browsing animals, and most of all the goat, are considered by
+foresters as more injurious to the growth of young trees, and,
+therefore, to the reproduction of the forest, than almost any other
+destructive cause. "According to Beatson's _Saint Helena_, introductory
+chapter, and Darwin's _Journal of Researches in Geology and Natural
+History_, pp. 582, 583," says Emsmann, in the notes to his translation
+of Foissac, p. 654, "it was the goats which destroyed the beautiful
+forests that, three hundred and fifty years ago, covered a continuous
+surface of not less than two thousand acres in the interior of the
+island [of St. Helena], not to mention scattered groups of trees. Darwin
+observes: 'During our stay at Valparaiso, I was most positively assured
+that sandal wood formerly grew in abundance on the island of Juan
+Fernandez, but that this tree had now become entirely extinct there,
+having been extirpated by the goats which early navigators had
+introduced. The neighboring islands, to which goats have not been
+carried, still abound in sandal wood.'"
+
+In the winter, the deer tribe, especially the great American moose deer,
+subsists much on the buds and young sprouts of trees; yet--though from
+the destruction of the wolves or from some not easily explained cause,
+these latter animals have recently multiplied so rapidly in some parts
+of North America, that, not long since, four hundred of them are said to
+have been killed, in one season, on a territory in Maine not comprising
+more than one hundred and fifty square miles--the wild browsing
+quadrupeds are rarely, if ever, numerous enough in regions uninhabited
+by man to produce any sensible effect on the condition of the forest. A
+reason why they are less injurious than the goat to young trees may be
+that they resort to this nutriment only in the winter, when the grasses
+and shrubs are leafless or covered with snow, whereas the goat feeds
+upon buds and young shoots principally in the season of growth. However
+this may be, the natural law of consumption and supply keeps the forest
+growth, and the wild animals which live on its products, in such a state
+of equilibrium as to insure the indefinite continuance of both, and the
+perpetuity of neither is endangered until man, who is above natural law,
+interferes and destroys the balance.
+
+When, however, deer are bred and protected in parks, they multiply like
+domestic cattle, and become equally injurious to trees. "A few years
+ago," says Clave, "there were not less than two thousand deer of
+different ages in the forest of Fontainebleau. For want of grass, they
+are driven to the trees, and they do not spare them. * * It is
+calculated that the browsing of these animals, and the consequent
+retardation of the growth of the wood, diminishes the annual product
+of the forest to the amount of two hundred thousand cubic feet per
+year, * * and besides this, the trees thus mutilated are soon exhausted
+and die. The deer attack the pines, too, tearing off the bark in long
+strips, or rubbing their heads against them when shedding their horns;
+and sometimes, in groves of more than a hundred hectares, not one pine
+is found uninjured by them."--_Revue des Deux Mondes_, Mai, 1863, p.
+157. See also _Appendix_, No. 21.
+
+Beckstein computes that a park of 2,500 acres, containing 250 acres of
+marsh, 250 of fields and meadows, and the remaining 2,000 of wood, may
+keep 364 deer of different species, 47 wild boars, 200 hares, 100
+rabbits, and an indefinite number of pheasants. These animals would
+require, in winter, 123,000 pounds of hay, and 22,000 pounds of
+potatoes, besides what they would pick up themselves. The natural forest
+most thickly peopled with wild animals would not, in temperate climates,
+contain, upon the average, one tenth of these numbers to the same extent
+of surface.
+
+[115] Even the volcanic dust of Etna remains very long unproductive.
+Near Nicolosi is a great extent of coarse black sand, thrown out in
+1669, which, for almost two centuries, lay entirely bare, and can be
+made to grow plants only by artificial mixtures and much labor.
+
+The increase in the price of wines, in consequence of the diminution of
+the product from the grape disease, however, has brought even these
+ashes under cultivation. "I found," says Waltershausen, referring to the
+years 1861-'62, "plains of volcanic sand and half-subdued lava streams,
+which twenty years ago lay utterly waste, now covered with fine
+vineyards. The ashfield of ten square miles above Nicolosi, created by
+the eruption of 1669, which was entirely barren in 1835, is now planted
+with vines almost to the summits of Monte Rosso, at a height of three
+thousand feet."--_Ueber den Sicilianischen Ackerbau_, p. 19.
+
+[116] _A Relation of a Journey Begun An. Dom._ 1610, lib. 4, p. 260,
+edition of 1627. The testimony of Sandys on this point is confirmed by
+that of Pighio, Braccini, Magliocco, Salimbeni, and Nicola di Rubeo, all
+cited by Roth, _Der Vesuv._, p. 9. There is some uncertainty about the
+date of the last eruption previous to the great one of 1631. Ashes,
+though not lava, appear to have been thrown out about the year 1500, and
+some chroniclers have recorded an eruption in the year 1306; but this
+seems to be an error for 1036, when a great quantity of lava was
+ejected. In 1139, ashes were thrown out for many days. I take those
+dates from the work of Roth just cited.
+
+[117] Except upon the banks of rivers or of lakes, the woods of the
+interior of North America, far from the habitations of man, are almost
+destitute of animal life. Dr. Newberry, describing the vast forests of
+the yellow pine of the West, _Pinus ponderosa_, remarks: "In the arid
+and desert regions of the interior basin, we made whole days' marches in
+forests of yellow pine, of which neither the monotony was broken by
+other forms of vegetation, nor its stillness by the flutter of a bird or
+the hum of an insect."--_Pacific Railroad Report_, vol. vi, 1857. Dr.
+NEWBERRY's _Report on Botany_, p. 37.
+
+The wild fruit and nut trees, the Canada plum, the cherries, the many
+species of walnut, the butternut, the hazel, yield very little,
+frequently nothing, so long as they grow in the woods; and it is only
+when the trees around them are cut down, or when they grow in pastures,
+that they become productive. The berries, too--the strawberry, the
+blackberry, the raspberry, the whortleberry, scarcely bear fruit at all
+except in cleared ground.
+
+The North American Indians did not inhabit the interior of the forests.
+Their settlements were upon the shores of rivers and lakes, and their
+weapons and other relics are found only in the narrow open grounds which
+they had burned over and cultivated, or in the margin of the woods
+around their villages.
+
+The rank forests of the tropics are as unproductive of human aliment as
+the less luxuriant woods of the temperate zone. In Strain's unfortunate
+expedition across the great American isthmus, where the journey lay
+principally through thick woods, several of the party died of
+starvation, and for many days the survivors were forced to subsist on
+the scantiest supplies of unnutritious vegetables perhaps never before
+employed for food by man. See the interesting account of that expedition
+in _Harper's Magazine_ for March, April, and May, 1855.
+
+Clave, as well as many earlier writers, supposes that primitive man
+derived his nutriment from the spontaneous productions of the wood. "It
+is to the forests," says he, "that man was first indebted for the means
+of subsistence. Exposed alone, without defence, to the rigor of the
+seasons, as well as to the attacks of animals stronger and swifter than
+himself, he found in them his first shelter, drew from them his first
+weapons. In the first period of humanity, they provided for all his
+wants: they furnished him wood for warmth, fruits for food, garments to
+cover his nakedness, arms for his defence."--_Etudes sur l'Economie
+Forestiere_, p. 13.
+
+But the history of savage life, as far as it is known to us, presents
+man in that condition as inhabiting only the borders of the forest and
+the open grounds that skirt the waters and the woods, and as finding
+only there the aliments which make up his daily bread.
+
+[118] The origin of the great natural meadows, or prairies as they are
+called, of the valley of the Mississippi, is obscure. There is, of
+course, no historical evidence on the subject, and I believe that
+remains of forest vegetation are seldom or never found beneath the
+surface, even in the _sloughs_, where the perpetual moisture would
+preserve such remains indefinitely. The want of trees upon them has been
+ascribed to the occasional long-continued droughts of summer, and the
+excessive humidity of the soil in winter; but it is, in very many
+instances, certain that, by whatever means the growth of forests upon
+them was first prevented or destroyed, the trees have been since kept
+out of them only by the annual burning of the grass, by grazing animals,
+or by cultivation. The groves and belts of trees which are found upon
+the prairies, though their seedlings are occasionally killed by drought,
+or by excess of moisture, extend themselves rapidly over them when the
+seeds and shoots are protected against fire, cattle, and the plough. The
+prairies, though of vast extent, must be considered as a local, and, so
+far as our present knowledge extends, abnormal exception to the law
+which clothes all suitable surfaces with forest; for there are many
+parts of the United States--Ohio, for example--where the physical
+conditions appear to be nearly identical with those of the States lying
+farther west, but where there were comparatively few natural meadows.
+The prairies were the proper feeding grounds of the bison, and the vast
+number of those animals is connected, as cause or consequence, with the
+existence of those vast pastures. The bison, indeed, could not convert
+the forest into a pasture, but he would do much to prevent the pasture
+from becoming a forest.
+
+There is positive evidence that some of the American tribes possessed
+large herds of domesticated bisons. See HUMBOLDT, _Ansichten der Natur_,
+i, pp. 71-73. What authorizes us to affirm that this was simply the wild
+bison reclaimed, and why may we not, with equal probability, believe
+that the migratory prairie buffalo is the progeny of the domestic animal
+run wild?
+
+There are, both on the prairies, as in Wisconsin, and in deep forests,
+as in Ohio, extensive remains of a primitive people, who must have been
+more numerous and more advanced in art than the present Indian tribes.
+There can be no doubt that the woods where such earthworks are found in
+Ohio were cleared by them, and that the vicinity of these fortresses or
+temples was inhabited by a large population. Nothing forbids the
+supposition that the prairies were cleared by the same or a similar
+people, and that the growth of trees upon them has been prevented by
+fires and grazing, while the restoration of the woods in Ohio may be due
+to the abandonment of that region by its original inhabitants. The
+climatic conditions unfavorable to the spontaneous growth of trees on
+the prairies may be an effect of too extensive clearings, rather than a
+cause of the want of woods. See _Appendix_, No. 22.
+
+[119] In many parts of the North American States, the first white
+settlers found extensive tracts of thin woods, of a very park-like
+character, called "oak openings," from the predominance of different
+species of that tree upon them. These were the semi-artificial pasture
+grounds of the Indians, brought into that state, and so kept, by partial
+clearing, and by the annual burning of the grass. The object of this
+operation was to attract the deer to the fresh herbage which sprang up
+after the fire. The oaks bore the annual scorching, at least for a
+certain time; but if it had been indefinitely continued, they would very
+probably have been destroyed at last. The soil would have then been much
+in the prairie condition, and would have needed nothing but grazing for
+a long succession of years to make the resemblance perfect. That the
+annual fires alone occasioned the peculiar character of the oak
+openings, is proved by the fact, that as soon as the Indians had left
+the country, young trees of many species sprang up and grew luxuriantly
+upon them. See a very interesting account of the oak openings in
+DWIGHT's _Travels_, iv, pp. 58-63.
+
+[120] The practice of burning over woodland, at once to clear and manure
+the ground, is called in Swedish _svedjande_, a participial noun from
+the verb _att svedja_, to burn over. Though used in Sweden as a
+preparation for crops of rye or other grain, it is employed in Lapland
+more frequently to secure an abundant growth of pasturage, which follows
+in two or three years after the fire; and it is sometimes resorted to as
+a mode of driving the Laplanders and their reindeer from the vicinity of
+the Swedish backwoodsman's grass grounds and haystacks, to which they
+are dangerous neighbors. The forest, indeed, rapidly recovers itself,
+but it is a generation or more before the reindeer moss grows again.
+When the forest consists of pine, _tall_, the ground, instead of being
+rendered fertile by this process, becomes hopelessly barren, and for a
+long time afterward produces nothing but weeds and briers.--LAESTADIUS,
+_Om Uppodlingar i Lappmarken_, p. 15. See also SCHUBERT, _Resa i
+Sverge_, ii, p. 375.
+
+In some parts of France this practice is so general that Clave says: "In
+the department of Ardennes it (_le sartage_) is the basis of
+agriculture. The northern part of the department, comprising the
+arrondissements of Rocroi and Mezieres, is covered by steep wooded
+mountains with an argillaceous, compact, moist and cold soil; it is
+furrowed by three valleys, or rather three deep ravines, at the bottom
+of which roll the waters of the Meuse, the Semoy, and the Sormonne, and
+villages show themselves wherever the walls of the valleys retreat
+sufficiently from the rivers to give room to establish them. Deprived of
+arable soil, since the nature of the ground permits neither regular
+clearing nor cultivation, the peasant of the Ardennes, by means of
+burning, obtains from the forest a subsistence which, without this
+resource, would fail him. After the removal of the disposable wood, he
+spreads over the soil the branches, twigs, briars, and heath, sets fire
+to them in the dry weather of July and August, and sows in September a
+crop of rye, which he covers by a light ploughing. Thus prepared, the
+ground yields from seventeen to twenty bushels an acre, besides a ton
+and a half or two tons of straw of the best quality for the manufacture
+of straw hats."--CLAVE, _Etudes sur l'Economie Forestiere_, p. 21.
+
+Clave does not expressly condemn the _sartage_, which indeed seems the
+only practicable method of obtaining crops from the soil he describes,
+but, as we shall see hereafter, it is regarded by most writers as a
+highly pernicious practice.
+
+[121] The remarkable mounds and other earthworks constructed in the
+valley of the Ohio and elsewhere in the territory of the United States,
+by a people apparently more advanced in culture than the modern Indian,
+were overgrown with a dense clothing of forest when first discovered by
+the whites. But though the ground where they were erected must have been
+occupied by a large population for a considerable length of time, and
+therefore entirely cleared, the trees which grew upon the ancient
+fortresses and the adjacent lands were not distinguishable in species,
+or even in dimensions and character of growth, from the neighboring
+forests, where the soil seemed never to have been disturbed. This
+apparent exception to the law of change of crop in natural forest growth
+was ingeniously explained by General Harrison's suggestion, that the
+lapse of time since the era of the mound builders was so great as to
+have embraced several successive generations of trees, and occasioned,
+by their rotation, a return to the original vegetation.
+
+The successive changes in the spontaneous growth of the forest, as
+proved by the character of the wood found in bogs, is not unfrequently
+such as to suggest the theory of a considerable change of climate during
+the human period. But the laws which govern the germination and growth
+of forest trees must be further studied, and the primitive local
+conditions of the sites where ancient woods lie buried must be better
+ascertained, before this theory can be admitted upon the evidence in
+question. In fact, the order of succession--for a rotation or
+alternation is not yet proved--may move in opposite directions in
+different countries with the same climate and at the same time. Thus in
+Denmark and in Holland the spike-leaved firs have given place to the
+broad-leaved beech, while in Northern Germany the process has been
+reversed, and evergreens have supplanted the oaks and birches of
+deciduous foliage. The principal determining cause seems to be the
+influence of light upon the germination of the seeds and the growth of
+the young tree. In a forest of firs, for instance, the distribution of
+the light and shade, to the influence of which seeds and shoots are
+exposed, is by no means the same as in a wood of beeches or of oaks, and
+hence the growth of different species will be stimulated in the two
+forests. See BERG, _Das Verdraengen der Laubwaelder im Noerdlichen
+Deutschland_, 1844. HEYER, _Das Verhalten der Waldbaeume gegen Licht und
+Schatten_, 1852. STARING, _De Bodem van Nederland_, 1856, i, pp.
+120-200. VAUPELL, _Om Boegens Indvandring i de Danske Skove_, 1857.
+KNORR, _Studien ueber die Buchen-Wirthschaft_, 1863.
+
+[122] There are, in Northern Italy and in Switzerland, joint-stock
+companies which insure against damage by hail, as well as by fire and
+lightning. Between the years 1854 and 1861, a single one of these
+companies, La Riunione Adriatica, paid, for damage by hail in Piedmont,
+Venetian Lombardy, and the Duchy of Parma, above 6,500,000 francs, or
+nearly $200,000 per year.
+
+[123] The _paragrandine_, or, as it is called in French, the
+_paragrele_, is a species of conductor by which it has been hoped to
+protect the harvests in countries particularly exposed to damage by
+hail. It was at first proposed to employ for this purpose poles
+supporting sheaves of straw connected with the ground by the same
+material; but the experiment was afterward tried in Lombardy on a large
+scale, with more perfect electrical conductors, consisting of poles
+secured to the top of tall trees and provided with a pointed wire
+entering the ground and reaching above the top of the pole. It was at
+first thought that this apparatus, erected at numerous points over an
+extent of several miles, was of some service as a protection against
+hail, but this opinion was soon disputed, and does not appear to be
+supported by well-ascertained facts. The question of a repetition of the
+experiment over a wide area has been again agitated within a very few
+years in Lombardy; but the doubts expressed by very able physicists as
+to its efficacy, and as to the point whether hail is an electrical
+phenomenon, have discouraged its advocates from attempting it.
+
+[124] _Cenni sulla Importanza e Coltura dei Boschi_, p. 6.
+
+[125] _Memoria sui Boschi, etc._, p. 44.
+
+[126] _Travels in Italy_, chap. iii.
+
+[127] _Le Alpi che cingono l'Italia_, i, p. 377.
+
+[128] "Long before the appearance of man, * * * they [the forests] had
+robbed the atmosphere of the enormous quantity of carbonic acid it
+contained, and thereby transformed it into respirable air. Trees heaped
+upon trees had already filled up the ponds and marshes, and buried with
+them in the bowels of the earth--to restore it to us after thousands of
+ages in the form of bituminous coal and of anthracite--the carbon which
+was destined to become, by this wonderful condensation, a precious store
+of future wealth."--CLAVE, _Etudes sur l'Economie Forestiere_, p. 13.
+
+This opinion of the modification of the atmosphere by vegetation is
+contested.
+
+[129] Schacht ascribes to the forest a specific, if not a measurable,
+influence upon the constitution of the atmosphere. "Plants imbibe from
+the air carbonic acid and other gaseous or volatile products exhaled by
+animals or developed by the natural phenomena of decomposition. On the
+other hand, the vegetable pours into the atmosphere oxygen, which is
+taken up by animals and appropriated by them. The tree, by means of its
+leaves and its young herbaceous twigs, presents a considerable surface
+for absorption and evaporation; it abstracts the carbon of carbonic
+acid, and solidifies it in wood, fecula, and a multitude of other
+compounds. The result is that a forest withdraws from the air, by its
+great absorbent surface, much more gas than meadows or cultivated
+fields, and exhales proportionally a considerably greater quantity of
+oxygen. The influence of the forests on the chemical composition of the
+atmosphere is, in a word, of the highest importance."--_Les Arbres_, p.
+111. See _Appendix_, No. 23.
+
+[130] Composition, texture and color of soil are important elements to
+be considered in estimating the effects of the removal of the forest
+upon its thermoscopic action. "Experience has proved," says Becquerel,
+"that when the soil is bared, it becomes more or less heated [by the
+rays of the sun] according to the nature and the color of the particles
+which compose it, and according to its humidity, and that, in the
+refrigeration resulting from radiation, we must take into the account
+the conducting power of those particles also. Other things being equal,
+silicious and calcareous sands, compared in equal volumes with different
+argillaceous earths, with calcareous powder or dust, with humus, with
+arable and with garden earth, are the soils which least conduct heat. It
+is for this reason that sandy ground, in summer, maintains a high
+temperature even during the night. We may hence conclude that when a
+sandy soil is stripped of wood, the local temperature will be raised.
+After the sands follow successively argillaceous, arable, and garden
+ground, then humus, which occupies the lowest rank. If we represent the
+power of calcareous sand to retain heat by 100, we have, according to
+Schubler,
+
+ For [silicious?] sand 95.6
+ " arable calcareous soil 74.8
+ " argillaceous earth 68.4
+ " garden earth 64.8
+ " humus 49.0
+
+"The retentive power of humus, then, is but half as great as that of
+calcareous sand. We will add that the power of retaining heat is
+proportional to the density. It has also a relation to the magnitude of
+the particles. It is for this reason that ground covered with silicious
+pebbles cools more slowly than silicious sand, and that pebbly soils are
+best suited to the cultivation of the vine, because they advance the
+ripening of the grape more rapidly than chalky and clayey earths, which
+cool quickly. Hence we see that in examining the calorific effects of
+clearing forests, it is important to take into account the properties of
+the soil laid bare."--BECQUEREL, _Des Climats et des Sols boises_, p.
+137.
+
+[131] "The Washington elm at Cambridge--a tree of no extraordinary
+size--was some years ago estimated to produce a crop of seven millions
+of leaves, exposing a surface of two hundred thousand square feet, or
+about five acres of foliage."--GRAY, _First Lessons in Botany and
+Vegetable Physiology_, as quoted by COULTAS, _What may be learned from a
+Tree_, p. 34.
+
+[132] See, on this particular point, and on the general influence of the
+forest on temperature, HUMBOLDT, _Ansichten der Natur_, i, 158.
+
+[133] The radiating and refrigerating power of objects by no means
+depends on their form alone. Melloni cut sheets of metal into the shape
+of leaves and grasses, and found that they produced little cooling
+effect, and were not moistened under atmospheric conditions which
+determined a plentiful deposit of dew on the leaves of vegetables.
+
+[134] BECQUEREL, _Des Climats, etc., Discours Prelim._ vi.
+
+[135] _Travels_, i, p. 61.
+
+[136] _Le Alpi che cingono l'Italia_, pp. 370, 371.
+
+[137] BERGSOeE, _Reventlovs Virksomhed_, ii, p. 125.
+
+[138] BECQUEREL, _Des Climats, etc._, p. 179.
+
+[139] Ibid., p. 116.
+
+[140] The following well-attested instance of a local change of climate
+is probably to be referred to the influence of the forest as a shelter
+against cold winds. To supply the extraordinary demand for Italian iron
+occasioned by the exclusion of English iron in the time of Napoleon I,
+the furnaces of the valleys of Bergamo were stimulated to great
+activity. "The ordinary production of charcoal not sufficing to feed the
+furnaces and the forges, the woods were felled, the copses cut before
+their time, and the whole economy of the forest was deranged. At
+Piazzatorre there was such a devastation of the woods, and consequently
+such an increased severity of climate, that maize no longer ripened.
+An association, formed for the purpose, effected the restoration
+of the forest, and maize flourishes again in the fields of
+Piazzatorre."--Report by G. ROSA, in _Il Politecnico_, Dicembre, 1861,
+p. 614.
+
+Similar ameliorations have been produced by plantations in Belgium. In
+an interesting series of articles by Baude, entitled "Les Cotes de la
+Manche," in the _Revue des Deux Mondes_, I find this statement: "A
+spectator placed on the famous bell tower of the cathedral of Antwerp,
+saw, not long since, on the opposite side of the Schelde only a vast
+desert plain; now he sees a forest, the limits of which are confounded
+with the horizon. Let him enter within its shade. The supposed forest is
+but a system of regular rows of trees, the oldest of which is not forty
+years of age. These plantations have ameliorated the climate which had
+doomed to sterility the soil where they are planted. While the tempest
+is violently agitating their tops, the air a little below is still, and
+sands far more barren than the plateau of La Hague have been
+transformed, under their protection, into fertile fields."--_Revue des
+Deux Mondes_, January, 1859, p. 277.
+
+[141] _Cenni sulla Importanza e Coltura dei Boschi_, p. 31.
+
+[142] _La Provence au point de vue des Torrents et des Inondations_, p.
+19.
+
+[143] _Ueber die Entwaldung der Gebirge_, p. 28.
+
+[144] BECQUEREL, _Des Climats, etc._, p. 9.
+
+[145] SALVAGNOLI, _Rapporto sul Bonificamento delle Maremme Toscane_,
+pp. xli, 124.
+
+[146] _Il Politecnico, Milano, Aprile e Maggio_, 1863, p. 35.
+
+[147] SALVAGNOLI, _Memorie sulle Maremme Toscane_, pp. 213, 214.
+
+[148] Except in the seething marshes of the tropics, where vegetable
+decay is extremely rapid, the uniformity of temperature and of
+atmospheric humidity renders all forests eminently healthful. See
+HOHENSTEIN's observations on this subject, _Der Wald_, p. 41.
+
+There is no question that open squares and parks conduce to the
+salubrity of cities, and many observers are of opinion that the trees
+and other vegetables with which such grounds are planted contribute
+essentially to their beneficial influence. See an article in _Aus der
+Natur_, xxii, p. 813.
+
+[149] _Memoria sui Boschi di Lombardia_, p. 45.
+
+[150] _Economie Rurale_, i, p. 22.
+
+[151] ROSSMAeSSLER, _Der Wald_, p. 158.
+
+[152] Ibid., p. 160.
+
+[153] The low temperature of air and soil at which, in the frigid zone,
+as well as in warmer latitudes under special circumstances, the
+processes of vegetation go on, seems to necessitate the supposition that
+all the manifestations of vegetable life are attended with an evolution
+of heat. In the United States, it is common to protect ice, in
+icehouses, by a covering of straw, which naturally sometimes contains
+kernels of grain. These often sprout, and even throw out roots and
+leaves to a considerable length, in a temperature very little above the
+freezing point. Three or four years since, I saw a lump of very clear
+and apparently solid ice, about eight inches long by six thick, on which
+a kernel of grain had sprouted in an icehouse, and sent half a dozen or
+more very slender roots into the pores of the ice and through the whole
+length of the lump. The young plant must have thrown out a considerable
+quantity of heat; for though the ice was, as I have said, otherwise
+solid, the pores through which the roots passed were enlarged to perhaps
+double the diameter of the fibres, but still not so much as to prevent
+the retention of water in them by capillary attraction. See _App._ 24.
+
+[154] BECQUEREL, _Des Climats, etc._, pp. 139-141.
+
+[155] Dr. Williams made some observations on this subject in 1789, and
+in 1791, but they generally belonged to the warmer months, and I do not
+know that any extensive series of comparisons between the temperature of
+the ground in the woods and the fields has been attempted in America.
+Dr. Williams's thermometer was sunk to the depth of ten inches, and gave
+the following results:
+
+ +-------------+--------------+--------------+-------------+
+ | | Temperature | Temperature | |
+ | TIME. | of ground in | of ground in | Difference. |
+ | | pasture. | woods. | |
+ +-------------+--------------+--------------+-------------+
+ | May 23 | 52 | 46 | 6 |
+ | " 28 | 57 | 48 | 9 |
+ | June 15 | 64 | 51 | 13 |
+ | " 27 | 62 | 51 | 11 |
+ | July 16 | 62 | 51 | 11 |
+ | " 30 | 651/2 | 551/2 | 10 |
+ | Aug. 15 | 68 | 58 | 10 |
+ | " 31 | 591/2 | 55 | 41/2 |
+ | Sept. 15 | 591/2 | 55 | 41/2 |
+ | Oct. 1 | 591/2 | 55 | 41/2 |
+ | " 15 | 49 | 49 | 0 |
+ | Nov. 1 | 43 | 43 | 0 |
+ | " 16 | 431/2 | 431/2 | 0 |
+ +-------------+--------------+--------------+-------------+
+
+On the 14th of January, 1791, in a winter remarkable for its extreme
+severity, he found the ground, on a plain open field where the snow had
+been blown away, frozen to the depth of three feet and five inches; in
+the woods where the snow was three feet deep, and where the soil had
+frozen to the depth of six inches before the snow fell, the thermometer,
+at six inches below the surface of the ground, stood at 39 deg.. In
+consequence of the covering of the snow, therefore, the previously
+frozen ground had been thawed and raised to seven degrees above the
+freezing point.--WILLIAMS'S _Vermont_, i, p. 74.
+
+Bodies of fresh water, so large as not to be sensibly affected by local
+influences of narrow reach or short duration, would afford climatic
+indications well worthy of special observation. Lake Champlain, which
+forms the boundary between the States of New York and Vermont, presents
+very favorable conditions for this purpose. This lake, which drains a
+basin of about 6,000 square miles, covers an area, excluding its
+islands, of about 500 square miles. It extends from lat. 43 deg. 30' to 45 deg.
+20', in very nearly a meridian line, has a mean width of four and a half
+miles, with an extreme breadth, excluding bays almost land-locked, of
+thirteen miles. Its mean depth is not well known. It is, however, 400
+feet deep in some places, and from 100 to 200 in many, and has few
+shoals or flats. The climate is of such severity that it rarely fails to
+freeze completely over, and to be safely crossed upon the ice, with
+heavy teams, for several weeks every winter. THOMPSON (_Vermont_, p. 14,
+and Appendix, p. 9) gives the following table of the times of the
+complete closing and opening of the ice, opposite Burlington, about the
+centre of the lake, and where it is ten miles wide.
+
+ +------+-------------+------------+-------+
+ | Year.| Closing. | Opening. | Days |
+ | | | |closed.|
+ +------+-------------+------------+-------+
+ | 1816 | February 9 | | |
+ | 1817 | January 29 | April 16 | 78 |
+ | 1818 | February 2 | April 15 | 72 |
+ | 1819 | March 4 | April 17 | 44 |
+ | 1820 |{February 3 | February | } 4 |
+ | |{March 8 | March 12 | } |
+ | 1821 | January 15 | April 21 | 95 |
+ | 1822 | January 24 | March 30 | 75 |
+ | 1823 | February 7 | April 5 | 57 |
+ | 1824 | January 22 | February 11| 20 |
+ | 1825 | February 9 | | |
+ | 1826 | February 1 | March 24 | 51 |
+ | 1827 | January 21 | March 31 | 68 |
+ | 1828 | not closed | | |
+ | 1829 | January 31 | April | |
+ | 1832 | February 6 | April 17 | 70 |
+ | 1833 | February 2 | April 6 | 63 |
+ | 1834 | February 13 | February 20| 7 |
+ | 1835 |{January 10 | January 23 | 18 |
+ | |{February 7 | April 12 | 64 |
+ | 1836 | January 27 | April 21 | 85 |
+ | 1837 | January 15 | April 26 | 101 |
+ | 1838 | February 2 | April 13 | 70 |
+ | 1839 | January 25 | April 6 | 71 |
+ | 1840 | January 25 | February 20| 26 |
+ | 1841 | February 18 | April 19 | 61 |
+ | 1842 | not closed | | |
+ | 1843 | February 16 | April 22 | 65 |
+ | 1844 | January 25 | April 11 | 77 |
+ | 1845 | February 3 | March 26 | 51 |
+ | 1846 | February 10 | March 26 | 44 |
+ | 1847 | February 15 | April 23 | 68 |
+ | 1848 | February 13 | February 26| 13 |
+ | 1849 | February 7 | March 23 | 44 |
+ | 1850 | not closed | | |
+ | 1851 | February 1 | March 12 | 89 |
+ | 1852 | January 18 | April 10 | 92 |
+ +------+-------------+------------+-------+
+
+In 1847, although, at the point indicated, the ice broke up on the 23d
+of April, it remained frozen much later at the North, and steamers were
+not able to traverse the whole length of the lake until May 6th.
+
+[156] We are not, indeed, to suppose that condensation of vapor and
+evaporation of water are going on in the same stratum of air at the same
+time, or, in other words, that vapor is condensed into raindrops, and
+raindrops evaporated, under the same conditions; but rain formed in one
+stratum, may fall through another, where vapor would not be condensed.
+Two saturated strata of different temperatures may be brought into
+contact in the higher regions, and discharge large raindrops, which, if
+not divided by some obstruction, will reach the ground, though passing
+all the time through strata which would vaporize them if they were in a
+state of more minute division.
+
+[157] It is perhaps too much to say that the influence of trees upon the
+wind is strictly limited to the mechanical resistance of their trunks,
+branches, and foliage. So far as the forest, by dead or by living
+action, raises or lowers the temperature of the air within it, so far it
+creates upward or downward currents in the atmosphere above it, and,
+consequently, a flow of air toward or from itself. These air streams
+have a certain, though doubtless a very small influence on the force and
+direction of greater atmospheric movements.
+
+[158] As a familiar illustration of the influence of the forest in
+checking the movement of winds, I may mention the well-known fact, that
+the sensible cold is never extreme in thick woods, where the motion of
+the air is little felt. The lumbermen in Canada and the Northern United
+States labor in the woods, without inconvenience, when the mercury
+stands many degrees below the zero of Fahrenheit, while in the open
+grounds, with only a moderate breeze, the same temperature is almost
+insupportable. The engineers and firemen of locomotives, employed on
+railways running through forests of any considerable extent, observe
+that, in very cold weather, it is much easier to keep up the steam while
+the engine is passing through the woods than in the open ground. As soon
+as the train emerges from the shelter of the trees the steam gauge
+falls, and the stoker is obliged to throw in a liberal supply of fuel to
+bring it up again.
+
+Another less frequently noticed fact, due, no doubt, in a great measure
+to the immobility of the air, is, that sounds are transmitted to
+incredible distances in the unbroken forest. Many instances of this have
+fallen under my own observation, and others, yet more striking, have
+been related to me by credible and competent witnesses familiar with a
+more primitive condition of the Anglo-American world. An acute observer
+of natural phenomena, whose childhood and youth were spent in the
+interior of one of the newer New England States, has often told me that
+when he established his home in the forest, he always distinctly heard,
+in still weather, the plash of horses' feet, when they forded a small
+brook nearly seven-eighths of a mile from his house, though a portion of
+the wood that intervened consisted of a ridge seventy or eighty feet
+higher than either the house or the ford.
+
+I have no doubt that, in such cases, the stillness of the air is the
+most important element in the extraordinary transmissibility of sound;
+but it must be admitted that the absence of the multiplied and confused
+noises, which accompany human industry in countries thickly peopled by
+man, contributes to the same result. We become, by habit, almost
+insensible to the familiar and never-resting voices of civilization in
+cities and towns; but the indistinguishable drone, which sometimes
+escapes even the ear of him who listens for it, deadens and often quite
+obstructs the transmission of sounds which would otherwise be clearly
+audible. An observer, who wishes to appreciate that hum of civic life
+which he cannot analyze, will find an excellent opportunity by placing
+himself on the hill of Capo di Monte at Naples, in the line of
+prolongation of the street called Spaccanapoli.
+
+It is probably to the stillness of which I have spoken, that we are to
+ascribe the transmission of sound to great distances at sea in calm
+weather. In June, 1853, I and my family were passengers on board a ship
+of war bound up the AEgean. On the evening of the 27th of that month, as
+we were discussing, at the tea table, some observations of Humboldt on
+this subject, the captain of the ship told us that he had once heard a
+single gun at sea at the distance of ninety nautical miles. The nest
+morning, though a light breeze had sprung up from the north, the sea was
+of glassy smoothness when we went on deck. As we came up, an officer
+told us that he had heard a gun at sunrise, and the conversation of the
+previous evening suggested the inquiry whether it could have been fired
+from the combined French and English fleet then lying at Beshika Bay.
+Upon examination of our position we were found to have been, at sunrise,
+ninety sea miles from that point. We continued beating up northward, and
+between sunrise and twelve o'clock meridian of the 28th, we had made
+twelve miles northing, reducing our distance from Beshika Bay to
+seventy-eight sea miles. At noon we heard several guns so distinctly
+that we were able to count the number. On the 29th we came up with the
+fleet, and learned from an officer who came on board that a royal salute
+had been fired at noon on the 28th, in honor of the day as the
+anniversary of the Queen of England's coronation. The report at sunrise
+was evidently the morning gun, those at noon the salute.
+
+Such cases are rare, because the sea is seldom still, and the
+[Greek: kymaton anerithmon gelasma] rarely silent, over so great a space
+as ninety or even seventy-eight nautical miles. I apply the epithet
+_silent_ to [Greek: gelasma] advisedly. I am convinced that AEschylus
+meant the audible laugh of the waves, which is indeed of _countless_
+multiplicity, not the visible smile of the sea, which, belonging to the
+great expanse as one impersonation, is single, though, like the human
+smile, made up of the play of many features.
+
+[159] "The presence of watery vapor in the air is general. * * *
+Vegetable surfaces are endowed with the power of absorbing gases,
+vapors, and also, no doubt, the various soluble bodies which are
+presented to them. The inhalation of humidity is carried on by the
+leaves upon a large scale; the dew of a cold summer night revives the
+groves and the meadows, and a single shower of rain suffices to refresh
+the verdure of a forest which a long drought had parched."--SCHACHT,
+_Les Arbres_, ix, p. 340.
+
+The absorption of the vapor of water by leaves is disputed. "The
+absorption of watery vapor by the leaves of plants is, according to
+Unger's experiments, inadmissible."--WILHELM, _Der Boden und das
+Wasser_, p. 19. If this latter view is correct, the apparently
+refreshing effects of atmospheric humidity upon vegetation must be
+ascribed to moisture absorbed by the ground from the air and supplied to
+the roots. In some recent experiments by Dr. Sachs, a porous flower-pot,
+with a plant growing in it, was left unwatered until the earth was dry,
+and the plant began to languish. The pot was then placed in a glass case
+containing air, which was kept always saturated with humidity, but no
+water was supplied, and the leaves of the plant were exposed to the open
+atmosphere. The soil in the flower pot absorbed from the air moisture
+enough to revive the foliage, and keep it a long time green, but not
+enough to promote development of new leaves.--Id., ibid., p. 18.
+
+[160] The experiments of Hales and others, on the absorption and
+exhalation of water by vegetables, are of the highest physiological
+interest; but observations on sunflowers, cabbages, hops, and single
+branches of isolated trees, growing in artificially prepared soils and
+under artificial conditions, furnish no trustworthy data for computing
+the quantity of water received and given off by the natural wood.
+
+[161] In the primitive forest, except where the soil is too wet for the
+dense growth of trees, the ground is generally too thickly covered with
+leaves to allow much room for ground mosses. In the more open woods of
+Europe, this form of vegetation is more frequent--as, indeed, are many
+other small plants of a more inviting character--than in the native
+American forest. See, on the cryptogams and wood plants, ROSSMAeSSLER,
+_Der Wald_, pp. 33 _et seqq._
+
+[162] Emerson (_Trees of Massachusetts_, p. 493) mentions a maple six
+feet in diameter, as having yielded a barrel, or thirty-one and a half
+gallons of sap in twenty-four hours, and another, the dimensions of
+which are not stated, as having yielded one hundred and seventy-five
+gallons in the course of the season. The _Cultivator_, an American
+agricultural journal, for June, 1842, states that twenty gallons of sap
+were drawn in eighteen hours from a single maple, two and a half feet in
+diameter, in the town of Warner, New Hampshire, and the truth of this
+account has been verified by personal inquiry made in my behalf. This
+tree was of the original forest growth, and had been left standing when
+the ground around it was cleared. It was tapped only every other year,
+and then with six or eight incisions. Dr. Williams (_History of
+Vermont_, i, p. 91) says: "A man much employed in making maple sugar,
+found that, for twenty-one days together, a maple tree discharged seven
+and a half gallons per day."
+
+An intelligent correspondent, of much experience in the manufacture of
+maple sugar, writes me that a second-growth maple, of about two feet in
+diameter, standing in open ground, tapped with four incisions, has, for
+several seasons, generally run eight gallons per day in fair weather. He
+speaks of a very large tree, from which sixty gallons were drawn in the
+course of a season, and of another, something more than three feet
+through, which made forty-two pounds of wet sugar, and must have yielded
+not less than one hundred and fifty gallons.
+
+[163] "The buds of the maple," says the same correspondent, "do not
+start till toward the close of the sugar season. As soon as they begin
+to swell, the sap seems less sweet, and the sugar made from it is of a
+darker color, and with less of the distinctive maple flavor."
+
+[164] "In this region, maples are usually tapped with a three-quarter
+inch bit, boring to the depth of one and a half or two inches. In the
+smaller trees, one incision only is made, two in those of eighteen
+inches in diameter, and four in trees of larger size. Two 3/4-inch holes
+in a tree twenty-two inches in diameter = 1/46 of the circumference, and
+1/169 of the area of section."
+
+"Tapping does not check the growth, but does injure the quality of the
+wood of maples. The wood of trees often tapped is lighter and less dense
+than that of trees which have not been tapped, and gives less heat in
+burning. No difference has been observed in the starting of the buds of
+tapped and untapped trees."--_Same correspondent._
+
+[165] Dr. Rush, in a letter to Jefferson, states the number of maples
+fit for tapping on an acre at from thirty to fifty. "This," observes my
+correspondent, "is correct with regard to the original growth, which is
+always more or less intermixed with other trees; but in second growth,
+composed of maples alone, the number greatly exceeds this. I have had
+the maples on a quarter of an acre, which I thought about an average of
+second-growth 'maple orchards,' counted. The number was found to be
+fifty-two, of which thirty-two were ten inches or more in diameter, and,
+of course, large enough to tap. This gives two hundred and eight trees
+to the acre, one hundred and twenty-eight of which were of proper size
+for tapping."
+
+According to the census returns, the quantity of maple sugar made
+in the United States in 1850 was 34,253,436 pounds; in 1860, it was
+38,863,884 pounds, besides 1,944,594 gallons of molasses. The cane
+sugar made in 1850 amounted to 237,133,000 pounds; in 1859, to
+302,205,000.--_Preliminary Report on the Eighth Census_, p. 88.
+
+According to Bigelow, _Les Etats Unis d'Amerique en 1863_, chap. iv, the
+sugar product of Louisiana alone for 1862 is estimated at 528,321,500
+pounds.
+
+[166] The correspondent already referred to informs me that a black
+birch, tapped about noon with two incisions, was found the next morning
+to have yielded sixteen gallons. Dr. Williams (_History of Vermont_, i,
+p. 91) says: "A large birch, tapped in the spring, ran at the rate of
+five gallons an hour when first tapped. Eight or nine days after, it was
+found to run at the rate of about two and a half gallons an hour, and at
+the end of fifteen days the discharge continued in nearly the same
+quantity. The sap continued to flow for four or five weeks, and it was
+the opinion of the observers that it must have yielded as much as sixty
+barrels [1,890 gallons]."
+
+[167] "The best state of weather for a good run," says my correspondent,
+"is clear days, thawing fast in the daytime and freezing well at night,
+with a gentle west or northwest wind; though we sometimes have clear,
+fine, thawing days followed by frosty nights, without a good run of sap,
+I have thought it probable that the irregular flow of sap on different
+days in the same season is connected with the variation in atmospheric
+pressure; for the atmospheric conditions above mentioned as those most
+favorable to a free flow of sap are also those in which the barometer
+usually indicates pressure considerably above the mean. With a south or
+southeast wind, and in lowering weather, which causes a fall in the
+barometer, the flow generally ceases, though the sap sometimes runs till
+after the beginning of the storm. With a _gentle_ wind, south of west,
+maples sometimes run all night. When this occurs, it is oftenest shortly
+before a storm. Last spring, the sap of a sugar orchard in a neighboring
+town flowed the greater part of the time for two days and two nights
+successively, and did not cease till after the commencement of a rain
+storm."
+
+The cessation of the flow of sap at night is perhaps in part to be
+ascribed to the nocturnal frost, which checks the melting of the snow,
+of course diminishing the supply of moisture in the ground, and
+sometimes congeals the strata from which the rootlets suck in water.
+From the facts already mentioned, however, and from other well-known
+circumstances--such, for example, as the more liberal flow of sap from
+incisions on the south side of the trunk--it is evident that the
+withdrawal of the stimulating influences of the sun's light and heat is
+the principal cause of the suspension of the circulation in the night.
+
+[168] "The flow ceases altogether soon after the buds begin to
+swell."--_Letter before quoted._
+
+[169] We might obtain a contribution to an approximate estimate of the
+quantity of moisture abstracted by forest vegetation from the earth and
+the air, by ascertaining, as nearly as possible, the quantity of wood on
+a given area, the proportion of assimilable matter contained in the
+fluids of the tree at different seasons of the year, the ages of the
+trees respectively, and the quantity of leaf and seed annually shed by
+them. The results would, indeed, be very vague, but they might serve to
+check or confirm estimates arrived at by other processes. The following
+facts are items too loose perhaps to be employed as elements in such a
+computation.
+
+Dr. Williams, who wrote when the woods of Northern New England were
+generally in their primitive condition, states the number of trees
+growing on an acre at from one hundred and fifty to six hundred and
+fifty, according to their size and the quality of the soil; the quantity
+of wood, at from fifty to two hundred cords, or from 238 to 952 cubic
+yards, but adds that on land covered with pines, the quantity of wood
+would be much greater. Whether he means to give the entire solid
+contents of the tree, or, as is usual in ordinary estimates in New
+England, the marketable wood only, the trunks and larger branches, does
+not appear. Next to the pine, the maple would probably yield a larger
+amount to a given area than any of the other trees mentioned by Dr.
+Williams, but mixed wood, in general, measures most. In a good deal of
+observation on this subject, the largest quantity of marketable wood I
+have ever known cut on an acre of virgin forest was one hundred and four
+cords, or 493 cubic yards, and half that amount is considered a very
+fair yield. The smaller trees, branches, and twigs would not increase
+the quantity more than twenty-five per cent., and if we add as much more
+for the roots, we should have a total of about 750 cubic yards. I think
+Dr. Williams's estimate too large, though it would fall much below the
+product of the great trees of the Mississippi Valley, of Oregon, and of
+California. It should be observed that these measurements are those of
+the wood as it lies when 'corded' or piled up for market, and exceed the
+real solid contents by not less than fifteen per cent.
+
+"In a soil of medium quality," says Clave, quoting the estimates of
+Pfeil, for the climate of Prussia, "the volume of a hectare of pines
+twenty years old, would exceed 80 cubic metres [421/2 cubic yards to
+the acre]; it would amount to but 24 in a meagre soil. This tree attains
+its maximum of mean growth at the age of seventy-five years. At that
+age, in the sandy earth of Prussia, it produces annually about 5 cubic
+metres, with a total volume of 311 cubic metres per hectare [166 cubic
+yards per acre]. After this age the volume increases, but the mean rate
+of growth diminishes. At eighty years, for instance, the volume is 335
+cubic metres, the annual production 4 only. The beech reaches its
+maximum of annual growth at one hundred and twenty years. It then has a
+total volume of 633 cubic metres to the hectare [335 cubic yards to the
+acre], and produces 5 cubic metres per year."--CLAVE, _Etudes_, p. 151.
+
+These measures, I believe, include the entire ligneous product of the
+tree, exclusive of the roots, and express the actual solid contents. The
+specific gravity of maple wood is stated to be 75. Maple sap yields
+sugar at the rate of about one pound _wet_ sugar to three gallons of
+sap, and wet sugar is to dry sugar in about the proportion of nineteen
+to sixteen. Besides the sugar, there is a small residuum of "sand,"
+composed of phosphate of lime, with a little silex, and it is certain
+that by the ordinary hasty process of manufacture, a good deal of sugar
+is lost; for the drops, condensed from the vapor of the boilers on the
+rafters of the rude sheds where the sap is boiled, have a decidedly
+sweet taste.
+
+[170] "The elaborated sap, passing out of the leaves, is received into
+the inner bark, * * * and a part of what descends finds its way even to
+the ends of the roots, and is all along diffused laterally into the
+stem, where it meets and mingles with the ascending crude sap or raw
+material. So there is no separate circulation of the two kinds of sap;
+and no crude sap exists separately in any part of the plant. Even in the
+root, where it enters, this mingles at once with some elaborated sap
+already there."--GRAY, _How Plants Grow_, Sec. 273.
+
+[171] Ward's tight glazed cases for raising, and especially for
+transporting plants, go far to prove that water only circulates through
+vegetables, and is again and again absorbed and transpired by organs
+appropriated to these functions. Seeds, growing grasses, shrubs, or
+trees planted in proper earth, moderately watered and covered with a
+glass bell or close frame of glass, live for months and even years, with
+only the original store of air and water. In one of Ward's early
+experiments, a spire of grass and a fern, which sprang up in a corked
+bottle containing a little moist earth introduced as a bed for a snail,
+lived and flourished for eighteen years without a new supply of either
+fluid. In these boxes the plants grow till the enclosed air is exhausted
+of the gaseous constituents of vegetation, and till the water has
+yielded up the assimilable matter it held in solution, and dissolved and
+supplied to the roots the nutriment contained in the earth in which they
+are planted. After this, they continue for a long time in a state of
+vegetable sleep, but if fresh air and water be introduced into the
+cases, or the plants be transplanted into open ground, they rouse
+themselves to renewed life, and grow vigorously, without appearing to
+have suffered from their long imprisonment. The water transpired by the
+leaves is partly absorbed by the earth directly from the air, partly
+condensed on the glass, along which it trickles down to the earth,
+enters the roots again, and thus continually repeats the circuit. See
+_Aus der Natur_, 21, B. S. 537.
+
+[172] WILHELM, _Der Boden und das Wasser_, p. 18. It is not ascertained
+in what proportions the dew is evaporated, and in what it is absorbed by
+the earth, in actual nature, but there can be no doubt that the amount
+of water taken up by the ground, both from vapor suspended in the air
+and from dew, is large. The annual fall of dew in England is estimated
+at five inches, but this quantity is much exceeded in many countries
+with a clearer sky. "In many of our Algerian campaigns," says Babinet,
+"when it was wished to punish the brigandage of the unsubdued tribes, it
+was impossible to set their grain fields on fire until a late hour of
+the day; for the plants were so wet with the night dew that it was
+necessary to wait until the sun had dried them."--_Etudes et Lectures_,
+ii, p. 212.
+
+[173] "It has been concluded that the dry land occupies about 49,800,000
+square statute miles. This does not include the recently discovered
+tracts of land in the vicinity of the poles, and allowing for yet
+undiscovered land (which, however, can only exist in small quantity), if
+we assign 51,000,000 to the land, there will remain about 146,000,000 of
+square miles for the extent of surface occupied by the ocean."--Sir J.
+F. W. HERSCHEL, _Physical Geography_, 1861, p. 19.
+
+It does not appear to which category Herschel assigns the inland seas
+and the fresh-water lakes and rivers of the earth; and Mrs. Somerville,
+who states that the "dry land occupies an area of 38,000,000 of square
+miles," and that "the ocean covers nearly three fourths of the surface
+of the globe," is equally silent on this point.--_Physical Geography_,
+fifth edition, p. 30. On the following page, Mrs. Somerville, in a note,
+cites Mr. Gardner as her authority, and says that, "according to his
+computation, the extent of land is about 37,673,000 square British
+miles, independently of Victoria Continent; and the sea occupies
+110,849,000. Hence the land is to the sea as 1 to 4 nearly." Sir John F.
+W. Herschel makes the area of dry land and ocean together 197,000,000
+square miles; Mrs. Somerville, or rather Mr. Gardner, 148,522,000. I
+suppose Sir John Herschel includes the islands in his aggregate of the
+"dry land," and the inland waters under the general designation of the
+"ocean," and that Mrs. Somerville excludes both.
+
+[174] It has been observed in Sweden that the spring, in many districts
+where the forests have been cleared off, now comes on a fortnight later
+than in the last century.--ASBJOeRNSEN, _Om Skovene i Norge_, p. 101.
+
+The conclusion arrived at by Noah Webster, in his very learned and able
+paper on the supposed change in the temperature of winter, read before
+the Connecticut Academy of Arts and Sciences in 1799, was as follows:
+"From a careful comparison of these facts, it appears that the weather,
+in modern winters, in the United States, is more inconstant than when
+the earth was covered with woods, at the first settlement of Europeans
+in the country; that the warm weather of autumn extends further into the
+winter months, and the cold weather of winter and spring encroaches upon
+the summer; that, the wind being more variable, snow is less permanent,
+and perhaps the same remark may be applicable to the ice of the rivers.
+These effects seem to result necessarily from the greater quantity of
+heat accumulated in the earth in summer since the ground has been
+cleared of wood and exposed to the rays of the sun, and to the greater
+depth of frost in the earth in winter by the exposure of its uncovered
+surface to the cold atmosphere."--_Collection of Papers by_ NOAH
+WEBSTER, p. 162.
+
+[175] I have seen, in Northern New England, the surface of the open
+ground frozen to the depth of twenty-two inches, in the month of
+November, when in the forest earth no frost was discoverable; and later
+in the winter, I have known an exposed sand knoll to remain frozen six
+feet deep, after the ground in the woods was completely thawed.
+
+[176]
+
+ ----Det golde Stroeg i Afrika,
+ Der Intet voxe kan, da ei det regner,
+ Og, omvendt, ingen Regn kan falde, da
+ Der Intet voxer.
+ PALUDAN-MUeLLER, _Adam Homo_, ii, 408.
+
+[177]
+
+ Und Stuerme brausen um die Wette
+ Vom Meer aufs Land, vom Land aufs Meer.
+ GOETHE, _Faust, Song of the Archangels_.
+
+[178] _Etudes sur l'Economie Forestiere_, pp. 45, 46.
+
+[179] I am not aware of any evidence to show that Malta had any woods of
+importance at any time since the cultivation of cotton was introduced
+there; and if it is true, as has been often asserted, that its present
+soil was imported from Sicily, it can certainly have possessed no
+forests since a very remote period. In Sandys's time, 1611, there were
+no woods in the island, and it produced little cotton. He describes it
+as "a country altogether champion, being no other than a rocke couered
+ouer with earth, but two feete deepe where the deepest; hauing but few
+trees but such as beare fruite. * * * So that their wood they haue from
+Sicilia." They have "an indifferent quantity of cotton wooll, but that
+the best of all other."--SANDYS, _Travels_, p. 228.
+
+[180] SCHACHT, _Les Arbres_, p. 412.
+
+[181] _What may be learned from a Tree_, p. 117.
+
+[182] _Der Wald_, p. 13.
+
+[183] _Om Skovene og deres Forhold til National[oe]conomien_, pp.
+131-133.
+
+[184] _Om Skovene og om et ordnet Skovbrug i Norge_, p. 106.
+
+[185] _Etudes et Lectures_, iv. p. 114.
+
+[186] The supposed increase in the frequency and quantity of rain in
+Lower Egypt is by no means established. I have heard it disputed on the
+spot by intelligent Franks, whose residence in that country began before
+the plantations of Mehemet Aali and Ibrahim Pacha, and I have been
+assured by them that meteorological observations, made at Alexandria
+about the beginning of this century, show an annual fall of rain as
+great as is usual at this day. The mere fact, that it did not rain
+during the French occupation, is not conclusive. Having experienced a
+gentle shower of nearly twenty-four hours' duration in Upper Egypt, I
+inquired of the local governor in relation to the frequency of this
+phenomenon, and was told by him that not a drop of rain had fallen at
+that point for more than two years previous.
+
+The belief in the increase of rain in Egypt rests almost entirely on the
+observations of Marshal Marmont, and the evidence collected by him in
+1836. His conclusions have been disputed, if not confuted, by Jomard and
+others, and are probably erroneous. See, FOISSAC, _Meteorologie_, German
+translation, pp. 634-639.
+
+It certainly sometimes rains briskly at Cairo, but evaporation is
+exceedingly rapid in Egypt--as any one, who ever saw a Fellah woman wash
+a napkin in the Nile, and dry it by shaking it a few moments in the air,
+can testify; and a heap of grain, wet a few inches below the surface,
+would probably dry again without injury. At any rate, the Egyptian
+Government often has vast quantities of wheat stored at Boulak, in
+uncovered yards through the winter, though it must be admitted that the
+slovenliness and want of foresight in Oriental life, public and private,
+are such that we cannot infer the safety of any practice followed in the
+East, merely from its long continuance.
+
+Grain, however, may be long kept in the open air in climates much less
+dry than that of Egypt, without injury, except to the superficial
+layers; for moisture does not penetrate to a great depth in a heap of
+grain once well dried, and kept well aired. When Louis IX was making his
+preparations for his campaign in the East, he had large quantities of
+wine and grain purchased in the Island of Cyprus, and stored up, for two
+years, to await his arrival. "When we were come to Cyprus," says
+Joinville, _Histoire de Saint Louis_, Sec.Sec. 72, 73, "we found there greate
+foison of the Kynge's purveyance. * * The wheate and the barley they had
+piled up in greate heapes in the feeldes, and to looke vpon, they were
+like vnto mountaynes; for the raine, the whyche hadde beaten vpon the
+wheate now a longe whyle, had made it to sproute on the toppe, so that
+it seemed as greene grasse. And whanne they were mynded to carrie it to
+Egypte, they brake that sod of greene herbe, and dyd finde under the
+same the wheate and the barley, as freshe as yf menne hadde but nowe
+thrashed it."
+
+[187] _Etude sur les Eaux au point de vue des Inondations_, p. 91.
+
+[188] _Economie Rurale_, ii, chap. xx, Sec. 4, pp. 756-759. See also p.
+733.
+
+[189] Jacini, speaking of the great Italian lakes, says: "A large
+proportion of the water of the lakes, instead of discharging itself by
+the Ticino, the Adda, the Oglio, the Mincio, filters through the
+silicious strata which underlie the hills, and follows subterranean
+channels to the plain, where it collects in the _fontanili_, and being
+thence conducted into the canals of irrigation, becomes a source of
+great fertility."--_La Proprieta Fondiaria, etc._, p. 144.
+
+[190] _Meteorologie_, German translation by EMSMANN, p. 605.
+
+[191] _Handbuch der Physischen Geographie_, p. 658.
+
+[192] _Annales des Ponts et Chaussees_, 1854, 1st semestre, pp. 21 _et
+seqq._ See the comments of VALLES on these observations, in his _Etudes
+sur les Inondations_, pp. 441 _et seqq._
+
+[193] The passage in Pliny is as follows: "Nascuntur fontes, decisis
+plerumque silvis, quos arborum alimenta consumebant, sicut in Haemo,
+obsidente Gallos Cassandro, quum valli gratia cecidissent. Plerumque
+vero damnosi torrentes corrivantur, detracta collibus silva continere
+nimbos ac digerere consueta."--_Nat. Hist._, xxxi, 30.
+
+Seneca cites this case, and another similar one said to have been
+observed at Magnesia, from a passage in Theophrastus, not to be found in
+the extant works of that author; but he adds that the stories are
+incredible, because shaded grounds abound most in water: fere
+aquosissima sunt quaecumque umbrosissima.--_Quaest. Nat._, iii, 11. _See
+Appendix_, No. 26.
+
+[194] "Why go so far for the proof of a phenomenon that is repeated
+every day under our own eyes, and of which every Parisian may convince
+himself, without venturing beyond the Bois de Boulogne or the forest of
+Meudon? Let him, after a few rainy days, pass along the Chevreuse road,
+which is bordered on the right by the wood, on the left by cultivated
+fields. The fall of water and the continuance of the rain have been the
+same on both sides; but the ditch on the side of the forest will remain
+filled with water proceeding from the infiltration through the wooded
+soil, long after the other, contiguous to the open ground, has performed
+its office of drainage and become dry. The ditch on the left will have
+discharged in a few hours a quantity of water, which the ditch on the
+right requires several days to receive and carry down to the
+valley."--CLAVE, _Etudes, etc._, pp. 53, 54.
+
+[195] VALLES, _Etudes sur les Inondations_, p. 472.
+
+[196] _Economie Rurale_, p. 730.
+
+[197] _Ueber die Entwaldung der Gebirge_, pp. 20 _et seqq._
+
+[198] _Physische Geographie_, p. 32.
+
+[199] _The Trees of America_, pp. 50, 51.
+
+[200] THOMPSON's _Vermont_, appendix, p. 8.
+
+[201] _Trees of America_, p. 48.
+
+[202] Dumont, following Dansse, gives an interesting extract from the
+Misopogon of the Emperor Julian, showing that, in the fourth century,
+the Seine--the level of which now varies to the extent of thirty feet
+between extreme high and extreme low water mark--was almost wholly
+exempt from inundations, and flowed with a uniform current through the
+whole year. "Ego olim eram in hibernis apud caram Lutetiam, [sic] enim
+Galli Parisiorum oppidum appellant, quae insula est non magna, in fluvio
+sita, qui eam omni ex parte eingit. Pontes sublicii utrinque ad eam
+ferunt, raroque fluvius minuitur ae crescit; sed qualis aestate, talis
+esse solet hyeme."--_Des Travaux Publics dans leur Rapports avec
+l'Agriculture_, p. 361, note.
+
+As Julian was six years in Gaul, and his principal residence was at
+Paris, his testimony as to the habitual condition of the Seine, at a
+period when the provinces where its sources originate were well wooded,
+is very valuable.
+
+[203] Almost every narrative of travel in those countries which were the
+earliest seats of civilization, contains evidence of the truth of these
+general statements, and this evidence is presented with more or less
+detail in most of the special works on the forest which I have occasion
+to cite. I may refer particularly to HOHENSTEIN, _Der Wald_, 1860, as
+full of important facts on this subject. See also CAIMI, _Cenni sulla
+Importanza dei Boschi_, for some statistics not readily found elsewhere,
+on this and other topics connected with the forest.
+
+[204] Stanley, citing SELDEN, _De Jure Naturali_, book vi, and
+FABRICIUS, _Cod. Pseudap._ V. T., i, 874, mentions a remarkable Jewish
+tradition of uncertain but unquestionably ancient date, which is among
+the oldest evidences of public respect for the woods, and of enlightened
+views of their importance and proper treatment:
+
+"To Joshua a fixed Jewish tradition ascribed ten decrees, laying down
+precise rules, which were instituted to protect the property of each
+tribe and of each householder from lawless depredation. Cattle, of a
+smaller kind, were to be allowed to graze in thick woods, not in thin
+woods; in woods, no kind of cattle without the owner's consent. Sticks
+and branches might be gathered by any Hebrew, but not cut. * * * Woods
+might be pruned, provided they were not olives or fruit trees, and that
+there was sufficient shade in the place."--_Lectures on the History of
+the Jewish Church_, part i, p. 271.
+
+[205] There seems to have been a tendency to excessive clearing in
+Central and Western, earlier than in Southeastern France. Wise and good
+Bernard Palissy--one of those persecuted Protestants of the sixteenth
+century, whose heroism, virtue, refinement, and taste shine out in such
+splendid contrast to the brutality, corruption, grossness, and barbarism
+of their oppressors--in the _Recepte Veritable_, first printed in 1563,
+thus complains: "When I consider the value of the least clump of trees,
+or even of thorns, I much marvel at the great ignorance of men, who, as
+it seemeth, do nowadays study only to break down, fell, and waste the
+fair forests which their forefathers did guard so choicely. I would
+think no evil of them for cutting down the woods, did they but replant
+again some part of them; but they care nought for the time to come,
+neither reck they of the great damage they do to their children which
+shall come after them."--_[OE]uvres Completes de Bernard Palissy_, 1844,
+p. 88.
+
+[206] The great naval and commercial marines of Venice and of Genoa must
+have occasioned an immense consumption of lumber in the Middle Ages, and
+the centuries immediately succeeding those commonly embraced in that
+designation. The marine construction of that period employed larger
+timbers than the modern naval architecture of most commercial countries,
+but apparently without a proportional increase of strength. The old
+modes of ship building have been, to a considerable extent, handed down
+to the present day in the Mediterranean, and an American or an
+Englishman looks with astonishment at the huge beams and thick planks so
+often employed in the construction of very small vessels navigating that
+sea. According to Hummel, the desolation of the Karst, the high plateau
+lying north of Trieste, now one of the most parched and barren districts
+in Europe, is owing to the felling of its woods to build the navies of
+Venice. "Where the miserable peasant of the Karst now sees nothing but
+bare rock swept and scoured by the raging Bora, the fury of this wind
+was once subdued by mighty firs, which Venice recklessly cut down to
+build her fleets."--_Physische Geographie_, p. 32. See _Appendix_, No.
+27.
+
+[207] _Le Alpi che cingono l'Italia_, i, p. 367.
+
+[208] See the periodical _Politecnico_, published at Milan, for the
+month of May, 1862, p. 234.
+
+[209] _Annali di Agricoltura, Industria e Commercio_, vol. i, p. 77.
+
+[210] HOLINSHED, reprint of 1807, i, pp. 357, 358. It is evident from
+this passage, and from another on page 397 of the same volume, that,
+though sea coal was largely exported to the Continent, it had not yet
+come into general use in England. It is a question of much interest,
+when coal was first employed in England for fuel. I can find no evidence
+that it was used as a combustible until more than a century after the
+Norman conquest. It has been said that it was known to the Anglo-Saxon
+population, but I am acquainted with no passage in the literature of
+that people which proves this. The dictionaries explain the Anglo-Saxon
+word _graefa_ by sea coal. I have met with this word in no Anglo-Saxon
+work, except in the _Chronicle_, A. D. 852, from a manuscript certainly
+not older than the twelfth century, and in that passage it may as
+probably mean peat as coal, and quite as probably something else as
+either. Coal is not mentioned in King Alfred's Bede, in Glanville, or in
+Robert of Gloucester, though all these writers speak of jet as found in
+England, and are full in their enumeration of the mineral products of
+the island.
+
+England was anciently remarkable for its forests, but Caesar says it
+wanted the _fagus_ and the _abies_. There can be no doubt that _fagus_
+means the beech, which, as the remains in the Danish peat mosses show,
+is a tree of late introduction into Denmark, where it succeeded the fir,
+a tree not now native to that country. The succession of forest crops
+seems to have been the same in England; for Harrison, p. 359, speaks of
+the "great store of firre" found lying "at their whole lengths" in the
+"fens and marises" of Lancashire and other counties, where not even
+bushes grew in his time. We cannot be sure what species of evergreen
+Caesar intended by _abies_. The popular designations of spike-leaved
+trees are always more vague and uncertain in their application than
+those of broad-leaved trees. _Pinus_, _pine_, has been very loosely
+employed even in botanical nomenclature, and _Kiefer_, _Fichte_, and
+_Tanne_ are often confounded in German.--ROSSMAeSSLER, _Der Wald_, pp.
+256, 289, 324. If it were certain that the _abies_ of Caesar was the fir
+formerly and still found in peat mosses, and that he was right in
+denying the existence of the beech in England in his time, the
+observation would be very important, because it would fix a date at
+which the fir had become extinct, and the beech had not yet appeared in
+the island.
+
+The English oak, though strong and durable, was not considered generally
+suitable for finer work in the sixteenth century. There were, however,
+exceptions. "Of all in Essex," observes HARRISON, _Holinshed_, i, p.
+357, "that growing in Bardfield parke is the finest for ioiners craft:
+for oftentimes haue I seene of their workes made of that oke so fine and
+faire, as most of the wainescot that is brought hither out of Danske;
+for our wainescot is not made in England. Yet diuerse haue assaied to
+deale without [with our] okes to that end, but not with so good successe
+as they haue hoped, bicause the ab or iuice will not so soone be remoued
+and cleane drawne out, which some attribute to want of time in the salt
+water."
+
+This passage is also of interest as showing that soaking in salt water,
+as a mode of seasoning, was practised in Harrison's time.
+
+But the importation of wainscot, or boards for ceiling, panelling, and
+otherwise finishing rooms, which was generally of oak, commenced three
+centuries before the time of Harrison. On page 204 of the _Liber
+Albus_--a book which could have been far more valuable if the editor had
+given us the texts, with his learned notes, instead of a
+translation--mention is made of "squared oak timber," brought in from
+the country by carts, and of course of domestic growth, as free of city
+duty or octroi, and of "planks of oak" coming in in the same way as
+paying one plank a cartload. But in the chapter on the "Customs of
+Billyngesgate," pp. 208, 209, relating to goods imported from foreign
+countries, a duty of one halfpenny is imposed on every hundred of boards
+called "weynscotte," and of one penny on every hundred of boards called
+"Rygholt." The editor explains "Rygholt" as "wood of Riga." This was
+doubtless pine or fir. The year in which these provisions were made does
+not appear, but they belong to the reign of Henry III.
+
+[211] In a letter addressed to the Minister of Public Works, after the
+terrible inundations of 1857, the Emperor thus happily expressed
+himself: "Before we seek the remedy for an evil, we inquire into its
+cause. Whence come the sudden floods of our rivers? From the water which
+falls on the mountains, not from that which falls on the plains. The
+waters which fall on our fields produce but few rivulets, but those
+which fall on our roofs and are collected in the gutters, form small
+streams at once. Now, the roofs are mountains--the gutters are valleys."
+
+"To continue the comparison," observes D'Hericourt, "roofs are smooth
+and impermeable, and the rain water pours rapidly off from their
+surfaces; but this rapidity of flow would be greatly diminished if the
+roofs were carpeted with mosses and grasses; more still, if they were
+covered with dry leaves, little shrubs, strewn branches, and other
+impediments--in short, if they were wooded."--_Annales Forestieres,
+Dec._, 1857, p. 311.
+
+[212] "The roots of vegetables," says D'Hericourt, "perform the office
+of a perpendicular drainage analogous to that which has been practised
+with success in Holland and in some parts of the British Islands. This
+system consists in driving down three or four thousand stakes upon a
+hectare; the rain water filters down along the stakes, and, in certain
+cases, as favorable results are obtained by this method as by horizontal
+drains."--_Annales Forestieres_, 1857, p. 312.
+
+[213] The productiveness of Egypt has been attributed too exclusively to
+the fertilizing effects of the slime deposited by the inundations of the
+Nile; for in that climate a liberal supply of water would produce good
+crops on almost any ordinary sand, while, without water, the richest
+soil would yield nothing. The sediment deposited annually is but a very
+small fraction of an inch in thickness. It is alleged that in quantity
+it would be hardly sufficient for a good top dressing, and that in
+quality it is not chemically distinguishable from the soil inches or
+feet below the surface. But to deny, as some writers have done, that the
+slime has any fertilizing properties at all, is as great an error as the
+opposite one of ascribing all the agricultural wealth of Egypt to that
+single cause of productiveness. Fine soils deposited by water are almost
+uniformly rich in all climates; those brought down by rivers, carried
+out into salt water, and then returned again by the tide, seem to be
+more permanently fertile than any others. The polders of the Netherland
+coast are of this character, and the meadows in Lincolnshire, which have
+been covered with slime by _warping_, as it is called, or admitting
+water over them at high tide, are remarkably productive. See _Appendix_,
+No. 28.
+
+[214] "The laws against clearing have never been able to prevent these
+operations when the proprietor found his advantage in them, and the long
+series of royal ordinances and decrees of parliaments, proclaimed from
+the days of Charlemagne to our own, with a view of securing forest
+property, have served only to show the impotence of legislative notion
+on this subject."--CLAVE, _Etudes sur l'Economie Forestiere_, p. 32.
+
+"A proprietor can always contrive to clear his woods, whatever may be
+done to prevent him; it is a mere question of time, and a few imprudent
+cuttings, a few abuses of the right of pasturage, suffice to destroy a
+forest in spite of all regulations to the contrary."--DUNOYER, _De la
+Liberte du Travail_, ii, p. 452, as quoted by Clave, p. 353.
+
+Both authors agree that the preservation of the forests in France is
+practicable only by their transfer to the state, which alone can protect
+them and secure their proper treatment. It is much to be feared that
+even this measure would be inadequate to save the forests of the
+American Union. There is little respect for public property in America,
+and the Federal Government, certainly, would not be the proper agent of
+the nation for this purpose. It proved itself unable to protect the
+live-oak woods of Florida, which were intended to be preserved for the
+use of the navy, and it more than once paid contractors a high price for
+timber stolen from its own forests. The authorities of the individual
+States might be more efficient.
+
+[215] See the lively account of the sale of a communal wood in
+BERLEPSCH, _Die Alpen, Holzschlaeger und Floesser_.
+
+[216] Streffleur (_Ueber die Natur und die Wirkungen der Wildbaeche_, p.
+3) maintains that all the observations and speculations of French
+authors on the nature of torrents had been anticipated by Austrian
+writers. In proof of this assertion he refers to the works of Franz von
+Zallinger, 1778, Von Arretin, 1808, Franz Duile, 1826, all published at
+Innsbruck, and HAGEN's _Beschreibung neuerer Wasserbauwerke_,
+Koenigsberg, 1826, none of which works are known to me. It is evident,
+however, that the conclusions of Surell and other French writers whom I
+cite, are original results of personal investigation, and not borrowed
+opinions.
+
+[217] Whether Palissy was acquainted with this ancient practice, or
+whether it was one of those original suggestions of which his works are
+so full, I know not; but in his treatise, _Des Eaux et Fontaines_, he
+thus recommends it, by way of reply to the objections of "Theorique,"
+who had expressed the fear that "the waters which rush violently down
+from the heights of the mountain would bring with them much earth, sand,
+and other things," and thus spoil the artificial fountain that
+"Practique" was teaching him to make: "And for hindrance of the
+mischiefs of great waters which may be gathered in few hours by great
+storms, when thou shalt have made ready thy parterre to receive the
+water, thou must lay great stones athwart the deep channels which
+lead to thy parterre. And so the force of the rushing currents
+shall be deadened, and thy water shall flow peacefully into his
+cisterns."--_[OE]uvres Completes_, p. 173.
+
+[218] Ladoucette says the peasant of Devoluy "often goes a distance of
+five hours over rocks and precipices for a single [man's] load of wood;"
+and he remarks on another page, that "the justice of peace of that
+canton had, in the course of forty-three years, but once heard the voice
+of the nightingale."--_Histoire, etc., des Hautes Alpes_, pp. 220, 434.
+
+[219] The valley of Embrun, now almost completely devastated, was once
+remarkable for its fertility. In 1806, Hericart de Thury said of it: "In
+this magnificent valley nature had been prodigal of her gifts. Its
+inhabitants have blindly revelled in her favors, and fallen asleep in
+the midst of her profusion."--BECQUEREL, _Des Climats, etc._, p. 314.
+
+[220] In the days of the Roman empire the Durance was a navigable river,
+with a commerce so important that the boatmen upon it formed a distinct
+corporation.--LADOUCETTE, _Histoire, etc., des Hautes Alpes_, p. 354.
+
+Even as early as 1789, the Durance was computed to have already covered
+with gravel and pebbles not less than 130,000 acres, "which, but for its
+inundations, would have been the finest land in the province."--ARTHUR
+YOUNG, _Travels in France_, vol. i, ch. i.
+
+[221] Between 1851 and 1856 the population of Languedoc and Provence had
+increased by 101,000 souls. The augmentation, however, was wholly in the
+provinces of the plains, where all the principal cities are found. In
+these provinces the increase was 204,000, while in the mountain
+provinces there was a diminution of 103,000. The reduction of the area
+of arable land is perhaps even more striking. In 1842, the department of
+the Lower Alps possessed 99,000 hectares, or nearly 245,000 acres, of
+cultivated soil. In 1852, it had but 74,000 hectares. In other words, in
+ten years 25,000 hectares, or 61,000 acres, had been washed away or
+rendered worthless for cultivation, by torrents and the abuses of
+pasturage.--CLAVE, _Etudes_, pp. 66, 67.
+
+[222] The Skalaera-Tobel, for instance, near Coire. See the description
+in BERLEPSCH, _Die Alpen_, pp. 169 _et seqq_, or in Stephen's English
+translation.
+
+The recent change in the character of the Mella--a river anciently so
+remarkable for the gentleness of its current that it was specially
+noticed by Catullus as flowing _molli flumine_--deserves more than a
+passing remark. This river rises in the mountain chain east of Lake
+Iseo, and traversing the district of Brescia, empties into the Oglio
+after a course of about seventy miles. The iron works in the upper
+valley of the Mella had long created a considerable demand for wood, but
+their operations were not so extensive as to occasion any very sudden or
+general destruction of the forests, and the only evil experienced from
+the clearings was the gradual diminution of the volume of the river.
+Within the last twenty years, the superior quality of the arms
+manufactured at Brescia has greatly enlarged the sale of them, and very
+naturally stimulated the activity of both the forges and of the colliers
+who supply them, and the hillsides have been rapidly stripped of their
+timber. Up to 1850, no destructive inundation of the Mella had been
+recorded. Buildings in great numbers had been erected upon its margin,
+and its valley was conspicuous for its rural beauty and its fertility.
+But when the denudation of the mountains had reached a certain point,
+avenging nature began the work of retribution. In the spring and summer
+of 1850 several new torrents were suddenly formed in the upper tributary
+valleys, and on the 14th and 15th of August in that year, a fall of
+rain, not heavier than had been often experienced, produced a flood
+which not only inundated much ground never before overflowed, but
+destroyed a great number of bridges, dams, factories, and other valuable
+structures, and, what was a far more serious evil, swept off from the
+rocks an incredible extent of soil, and converted one of the most
+beautiful valleys of the Italian Alps into a ravine almost as bare and
+as barren as the savagest gorge of Southern France. The pecuniary damage
+was estimated at many millions of francs, and the violence of the
+catastrophe was deemed so extraordinary, even in a country subject to
+similar visitations, that the sympathy excited for the sufferers
+produced, in five months, voluntary contributions for their relief to
+the amount of nearly $200,000--_Delle Inondazioni del Mella, etc., nella
+notte del 14 al 15 Agosto_, 1850.
+
+The author of this remarkable pamphlet has chosen as a motto a passage
+from the Vulgate translation of Job, which is interesting as showing
+accurate observation of the action of the torrent: "Mons cadens definit,
+et saxum transfertur de loco suo; lapides excavant aquae et alluvione
+paullatim terra consumitur."--_Job_ xiv, 18, 19.
+
+The English version is much less striking, and gives a different sense.
+
+[223] Streffleur quotes from Duile the following observations: "The
+channel of the Tyrolese brooks is often raised much above the valleys
+through which they flow. The bed of the Fersina is elevated high above
+the city of Trient, which lies near it. The Villerbach flows at a much
+more elevated level than that of the market place of Neumarkt and Vill,
+and threatens to overwhelm both of them with its waters. The Talfer at
+Botzen is at least even with the roofs of the adjacent town, if not
+above them. The tower steeples of the villages of Schlanders, Kortsch,
+and Laas, are lower than the surface of the Gadribach. The Saldurbach at
+Schluderns menaces the far lower village with destruction, and the chief
+town, Schwaz, is in similar danger from the Lahnbach."--STREFFLEUR,
+_Ueber die Wildbaeche, etc._, p. 7.
+
+[224] The snow drifts into the ravines and accumulates to incredible
+depths, and the water resulting from its dissolution and from the
+deluging rains which fall in spring, and sometimes in the summer, being
+confined by rocky walls on both sides, rises to a very great height, and
+of course acquires an immense velocity and transporting power in its
+rapid descent to its outlet from the mountain. In the winter of
+1842--'3, the valley of the Doveria, along which the Simplon road
+passes, was filled with solid snowdrifts to the depth of a hundred feet
+above the carriage road, and the sledge track by which passengers and
+the mails were carried ran at that height.
+
+Other things being equal, the transporting power of the water is
+greatest where its flow is most rapid. This is usually in the direction
+of the axis of the ravine. As the current pours out of the gorge and
+escapes from the lateral confinement of its walls, it spreads and
+divides itself into numerous smaller streams, which shoot out from the
+mouth of the valley, as from a centre, in different directions, like the
+ribs of a fan from the pivot, each carrying with it its quota of stones
+and gravel. The plain below the point of issue from the mountain is
+rapidly raised by newly formed torrents, the elevation depending on the
+inclination of the bed and the form and weight of the matter
+transported. Every flood both increases the height of this central point
+and extends the entire circumference of the deposit. The stream
+retaining most nearly the original direction moves with the greatest
+momentum, and consequently transports the solid matter with which it is
+charged to the greatest distance.
+
+The untravelled reader will comprehend this the better when he is
+informed that the southern slope of the Alps generally rises suddenly
+out of the plain, with no intervening hill to break the abruptness of
+the transition, except those consisting of comparatively small heaps of
+its own debris brought down by ancient glaciers or recent torrents. The
+torrents do not wind down valleys gradually widening to the rivers or
+the sea, but leap at once from the flanks of the mountains upon the
+plains below. This arrangement of surfaces naturally facilitates the
+formation of vast deposits at their points of emergence, and the centre
+of the accumulation in the case of very small torrents is not
+unfrequently a hundred feet high, and sometimes very much more.
+
+Torrents and the rivers that receive them transport mountain debris to
+almost incredible distances. Lorentz, in an official report on this
+subject, as quoted by Marschand from the Memoirs of the Agricultural
+Society of Lyons, says: "The felling of the woods produces torrents
+which cover the cultivated soil with pebbles and fragments of rock, and
+they do not confine their ravages to the vicinity of the mountains, but
+extend them into the fertile fields of Provence and other departments,
+to the distance of forty or fifty leagues."--_Entwaldung der Gebirge_,
+p. 17.
+
+[225] The precipitous walls of the Val de Lys, and more especially of
+the Val Doveria, though here and there shattered, show in many places a
+smoothness of face over a large vertical plane, at the height of
+hundreds of feet above the bottom of the valley, which no known agency
+but glacier ice is capable of producing, and of course they can have
+undergone no sensible change at those points for a vast length of time.
+The beds of the rivers which flow through those valleys suffer lateral
+displacement occasionally, where there is room for the shifting of the
+channel; but if any elevation or depression takes place in them, it is
+too slow to be perceptible except in case of some merely temporary
+obstruction.
+
+[226] Lombardini found, twenty years ago, that the mineral matter
+brought down to the Po by its tributaries was, in general, comminuted to
+about the same degree of fineness as the sands of its bed at their
+points of discharge. In the case of the Trebbia, which rises high in the
+Apennines and empties into the Po at Piacenza, it was otherwise, that
+river rolling pebbles and coarse gravel into the channel of the
+principal stream. The banks of the other affluents--excepting some of
+those which discharge their waters into the great lakes--then either
+retained their woods, or had been so long clear of them, that the
+torrents had removed most of the disintegrated and loose rock in their
+upper basins. The valley of the Trebbia had been recently cleared, and
+all the forces which tend to the degradation and transportation of rock
+were in full activity.--_Notice sur les Rivieres de la Lombardie,
+Annales des Ponts et Chaussees_, 1847, 1er semestre, p. 131.
+
+Since the date of Lombardini's observations, many Alpine valleys have
+been stripped of their woods. It would be interesting to know whether
+any sensible change has been produced in the character or quantity of
+the matter transported by them to the Po.
+
+[227] In proportion as the dikes are improved, and breaches and the
+escape of the water through them are less frequent, the height of the
+annual inundations is increased. Many towns on the banks of the river,
+and of course within the system of parallel embankments, were formerly
+secure from flood by the height of the artificial mounds on which they
+were built; but they have recently been obliged to construct ring dikes
+for their protection.--BAUMGARTEN, after LOMBARDINI, in the paper last
+quoted, pp. 141, 147.
+
+[228] Three centuries ago, when the declivities of the mountains still
+retained a much larger proportion of their woods, the moderate annual
+floods of the Po were occasioned by the melting of the snows, and, as
+appears by a passage of Tasso quoted by Castellani (_Dell' Influenza
+delle Selve_, i, p. 58, note), they took place in May. The much more
+violent inundations of the present century are due to rains, the waters
+of which are no longer retained by a forest soil, but conveyed at once
+to the rivers--and they occur almost uniformly in the autumn or late
+summer. Castellani, on the page just quoted, says that even so late as
+about 1780, the Po required a heavy rain of a week to overflow its
+banks, but that forty years later, it was sometimes raised to full flood
+in a single day.
+
+[229] This change of coast line cannot be ascribed to upheaval, for a
+comparison of the level of old buildings--as, for instance, the church
+of San Vitale and the tomb of Theodoric at Ravenna--with that of the
+sea, tends to prove a depression rather than an elevation of their
+foundations.
+
+A computation by a different method makes the deposits at the mouth of
+the Po 2,123,000 metres less; but as both of them omit the gravel and
+silt rolled, if not floated, down at ordinary and low water, we are safe
+in assuming the larger quantity.--_Article last quoted_, p. 174. (See
+note, p. 329)
+
+[230] Mengotti estimated the mass of solid matter annually "united to
+the waters of the Po" at 822,000,000 cubic metres, or nearly twenty
+times as much as, according to Lombardini, that river delivers into the
+Adriatic. Castellani supposes the computation of Mengotti to fall much
+below the truth, and there can be no doubt that a vastly larger quantity
+of earth and gravel is washed down from the Alps and the Apennines than
+is carried to the sea.--CASTELLANI, _Dell' Immediata Influenza delle
+Selve sul corso delle Acque_, i, pp. 42, 43.
+
+I have contented myself with assuming less than one fifth of Mengotti's
+estimate.
+
+[231] BAUMGARTEN, _An. des Ponts et Chaussees_, 1847, 1er semestre, p.
+175.
+
+[232] The total superficies of the basin of the Po, down to Ponte
+Lagoscuro [Ferrara]--a point where it has received all its affluents--is
+6,938,200 hectares, that is, 4,105,600 in mountain lands, 2,832,600 in
+plain lands.--DUMONT, _Travaux Publics, etc._, p. 272.
+
+These latter two quantities are equal respectively to 10,145,348, and
+6,999,638 acres, or 15,852 and 10,937 square miles.
+
+[233] I do not use the numbers I have borrowed or assumed as factors the
+value of which is precisely ascertained; nor, for the purposes of the
+present argument, is quantitative exactness important. I employ
+numerical statements simply as a means of aiding the imagination to form
+a general and certainly not extravagant idea of the extent of
+geographical revolutions which man has done much to accelerate, if not,
+strictly speaking, to produce.
+
+There is an old proverb, _Dolus latet in generalibus_, and Arthur Young
+is not the only public economist who has warned his readers against the
+deceitfulness of round numbers. I think, on the contrary, that vastly
+more error has been produced by the affectation of precision in cases
+where precision is impossible. In all the great operations of
+terrestrial nature, the elements are so numerous and so difficult of
+exact appreciation, that, until the means of scientific observation and
+measurement are much more perfected than they now are, we must content
+ourselves with general approximations. I say _terrestrial_ nature,
+because in cosmical movements we have fewer elements to deal with, and
+may therefore arrive at much more rigorous accuracy in determination of
+time and place than we can in fixing and predicting the quantities and
+the epochs of variable natural phenomena on the earth's surface.
+
+The value of a high standard of accuracy in scientific observation can
+hardly be overrated; but habits of rigorous exactness will never be
+formed by an investigator who allows himself to trust implicitly to the
+numerical precision of the results of a few experiments. The wonderful
+accuracy of geodetic measurements in modern times is, in general,
+attained by taking the mean of a great number of observations at every
+station, and this final precision is but the mutual balance and
+compensation of numerous errors.
+
+Travellers are often misled by local habits in the use of what may be
+called representative numbers, where a definite is put for an indefinite
+quantity. A Greek, who wished to express the notion of a great, but
+undetermined number, used "myriad, or ten thousand;" a Roman, "six
+hundred;" an Oriental, "forty," or, at present, very commonly, "fifteen
+thousand." Many a tourist has gravely repeated, as an ascertained fact,
+the vague statement of the Arabs and the monks of Mount Sinai, that the
+ascent from the convent of St. Catherine to the summit of Gebel Moosa
+counts "fifteen thousand" steps, though the difference of level is
+barely two thousand feet, and the "Forty" Thieves, the "forty" martyr
+monks of the convent of El Arbain--not to speak of a similar use of this
+numeral in more important cases--have often been understood as
+expressions of a known number, when in fact they mean simply _many_. The
+number "fifteen thousand" has found its way to Rome, and De Quincey
+seriously informs us, on the authority of a lady who had been at much
+pains to ascertain the _exact_ truth, that, including closets large
+enough for a bed, the Vatican contains fifteen thousand rooms. Any one
+who has observed the vast dimensions of most of the apartments of that
+structure will admit that we make a very small allowance of space when
+we assign a square rod, sixteen and a half feet square, to each room
+upon the average. On an acre, there might be one hundred and sixty such
+rooms, including partition walls; and, to contain fifteen thousand of
+them, a building must cover more than nine acres, and be ten stories
+high, or possess other equivalent dimensions, which, as every traveller
+knows, many times exceeds the truth.
+
+That most entertaining writer, About, reduces the number of rooms in the
+Vatican, but he compensates this reduction by increased dimensions, for
+he uses the word _salle_, which cannot be applied to closets barely
+large enough to contain a bed. According to him, there are in that
+"presbytere," as he irreverently calls it, twelve thousand large rooms
+[_salles_], thirty courts, and three hundred staircases.--_Rome
+Contemporaire_, p. 68.
+
+The pretended exactness of statistical tables is generally little better
+than an imposture; and those founded not on direct estimation by
+competent observers, but on the report of persons who have no particular
+interest in knowing, but often have a motive for distorting, the
+truth--such as census returns--are commonly to be regarded as but vague
+guesses at the actual fact.
+
+Fuller, who, for the combination of wit, wisdom, fancy, and personal
+goodness, stands first in English literature, thus remarks on the
+pretentious exactness of historical and statistical writers: "I approve
+the plain, country By-word, as containing much Innocent Simplicity
+therein,
+
+ _'Almost and very nigh
+ Have saved many a Lie.'_
+
+So have the Latines their _prope_, _fere_, _juxta_, _circiter_, _plus
+minus_, used in matters of fact by the most authentic Historians. Yea,
+we may observe that the Spirit of Truth itself, where _Numbers_ and
+_Measures_ are concerned, in Times, Places, and Persons, useth the
+aforesaid Modifications, save in such cases where some mystery contained
+in the number requireth a particular specification thereof:
+
+ In Times. | In Places. | In Person.
+ | |
+ Daniel, 5:33. | Luke, 24:13. | Exodus, 12:37.
+ Luke, 3:23. | John, 6:19. | Acts, 2:41.
+
+None therefore can justly find fault with me, if, on the like occasion,
+I have secured myself with the same Qualifications. Indeed, such
+Historians who grind their Intelligence to the _powder of fraction_,
+pretending to _cleave the pin_, do sometimes _misse the But_. Thus, one
+reporteth, how in the Persecution under _Dioeletian_, there were neither
+under nor over, but just _nine hundred ninety-nine_ martyrs. Yea,
+generally those that trade in such _Retail-ware_, and deal in such small
+parcells, may by the ignorant be commended for their _care_, but
+condemned by the judicious for their ridiculous _curiosity_."--_The
+History of the Worthies of England_, i, p. 59.
+
+[234] SURELL, _Les Torrents des Hautes Alpes_, chap. xxiv. In such
+cases, the clearing of the ground, which, in consequence of a temporary
+diversion of the waters, or from some other cause, has become rewooded,
+sometimes renews the ravages of the torrent. Thus, on the left bank of
+the Durance, a wooded declivity had been formed by the debris brought
+down by torrents, which had extinguished themselves after having swept
+off much of the superficial strata of the mountain of Morgon. "All this
+district was covered with woods, which have now been thinned out and are
+perishing from day to day; consequently, the torrents have recommenced
+their devastations, and if the clearings continue, this declivity, now
+fertile, will be ruined, like so many others."--Id., p. 155.
+
+[235] Where a torrent has not been long in operation, and earth still
+remains mixed with the rocks and gravel it heaps up at its point of
+eruption, vegetation soon starts up and prospers, if protected from
+encroachment. In Provence, "several communes determined, about ten years
+ago, to reserve the soils thus wasted, that is, to abandon them for a
+certain time, to spontaneous vegetation, which was not slow in making
+its appearance."--BECQUEREL, _Des Climats_, p. 315.
+
+[236] Rock is permeable by water to a greater extent than is generally
+supposed. Freshly quarried marble, and even granite, as well as most
+other stones, are sensibly heavier, as well as softer and more easily
+wrought, than after they are dried and hardened by air-seasoning. Many
+sandstones are porous enough to serve as filters for liquids, and much
+of that of Upper Egypt and Nubia hisses audibly when thrown into water,
+from the escape of the air forced out of it by hydrostatic pressure and
+the capillary attraction of the pores for water. See _Appendix_, No. 29.
+
+[237] Palissy had observed the action of frost in disintegrating rock,
+and he thus describes it, in his essay on the formation of ice: "I know
+that the stones of the mountains of Ardennes be harder than marble.
+Nevertheless, the people of that country do not quarry the said stones
+in winter, for that they be subject to frost; and many times the rocks
+have been seen to fall without being cut, by means whereof many people
+have been killed, when the said rocks were thawing." Palissy was
+ignorant of the expansion of water in freezing--in fact he supposed that
+the mechanical force exerted by freezing water was due to compression,
+not dilatation--and therefore he ascribes to thawing alone effects
+resulting not less from congelation.
+
+Various forces combine to produce the stone avalanches of the higher
+Alps, the fall of which is one of the greatest dangers incurred by the
+adventurous explorers of those regions--the direct action of the sun
+upon the stone, the expansion of freezing water, and the loosening of
+masses of rock by the thawing of the ice which supported them or held
+them together.
+
+[238] WESSELY, _Die Oesterreichischen Alpenlaender und ihre Forste_, pp.
+125, 126. Wessely records several other more or less similar occurrences
+in the Austrian Alps. Some of them, certainly, are not to be ascribed to
+the removal of the woods, but in most cases they are clearly traceable
+to that cause.
+
+[239] BIANCHI, Appendix to the Italian translation of Mrs. SOMERVILLE's
+_Physical Geography_, p. xxxvi.
+
+[240] See in KOHL, _Alpenreisen_, i, 120, an account of the ruin of
+fields and pastures, and even of the destruction of a broad belt of
+forest, by the fall of rocks in consequence of cutting a few large
+trees. Cattle are very often killed in Switzerland by rock avalanches,
+and their owners secure themselves from loss by insurance against this
+risk as against damage by fire or hail.
+
+[241] _Entwaldung der Gebirge_, p. 41.
+
+[242] The importance of the wood in preventing avalanches is well
+illustrated by the fact that, where the forest is wanting, the
+inhabitants of localities exposed to snow slides often supply the place
+of the trees by driving stakes through the snow into the ground, and
+thus checking its propensity to slip. The woods themselves are sometimes
+thus protected against avalanches originating on slopes above them, and
+as a further security, small trees are cut down along the upper line of
+the forest, and laid against the trunks of larger trees, transversely to
+the path of the slide, to serve as a fence or dam to the motion of an
+incipient avalanche, which may by this means be arrested before it
+acquires a destructive velocity and force.
+
+[243] The tide rises at Quebec to the height of twenty-five feet, and
+when it is aided by a northeast wind, it flows with almost irresistible
+violence. Rafts containing several hundred thousand cubic feet of timber
+are often caught by the flood tide, torn to pieces, and dispersed for
+miles along the shores.
+
+[244] One of these, the Baron of Renfrew--so named from one of the
+titles of the kings of England--built thirty or forty years ago,
+measured 5,000 tons. They were little else than rafts, being almost
+solid masses of timber designed to be taken to pieces and sold as lumber
+on arriving at their port of destination.
+
+The lumber trade at Quebec is still very large. According to a recent
+article in the _Revue des Deux Mondes_, that city exported, in 1860,
+30,000,000 cubic feet of squared timber, and 400,000,000 square feet of
+"planches." The thickness of the boards is not stated, but I believe
+they are generally cut an inch and a quarter thick for the Quebec trade,
+and as they shrink somewhat in drying, we may estimate ten square for
+one cubic foot of boards. This gives a total of 70,000,000 cubic feet.
+The specific gravity of white pine is .554, and the weight of this
+quantity of lumber, very little of which is thoroughly seasoned, would
+exceed a million of tons, even supposing it to consist wholly of wood as
+light as pine. New Brunswick, too, exports a large amount of lumber.
+
+[245] This name, from the French _chantier_, which has a wider meaning,
+is applied in America to temporary huts or habitations erected for the
+convenience of forest life, or in connection with works of material
+improvement.
+
+[246] Trees differ much in their power of resisting the action of forest
+fires. Different woods vary greatly in combustibility, and even when
+their bark is scarcely scorched, they are, partly in consequence of
+physiological character, and partly from the greater or less depth at
+which their roots habitually lie below the surface, very differently
+affected by running fires. The white pine, _Pinus strobus_, as it is the
+most valuable, is also perhaps the most delicate tree of the American
+forest, while its congener, the Northern pitch pine, _Pinus rigida_, is
+less injured by fire than any other tree of that country. I have heard
+experienced lumbermen maintain that the growth of this pine was even
+accelerated by a fire brisk enough to destroy all other trees, and I
+have myself seen it still flourishing after a conflagration which had
+left not a green leaf but its own in the wood, and actually throwing out
+fresh foliage, when the old had been quite burnt off and the bark almost
+converted into charcoal. The wood of the pitch pine is of comparatively
+little value for the joiner, but it is useful for very many purposes.
+Its rapidity of growth in even poor soils, its hardihood, and its
+abundant yield of resinous products, entitle it to much more
+consideration, as a plantation tree, than it has hitherto received in
+Europe or America.
+
+[247] Between fifty and sixty years ago, a steep mountain with which I
+am very familiar, composed of metamorphic rock, and at that time covered
+with a thick coating of soil and a dense primeval forest, was
+accidentally burnt over. The fire took place in a very dry season, the
+slope of the mountain was too rapid to retain much water, and the
+conflagration was of an extraordinarily fierce character, consuming the
+wood almost entirely, burning the leaves and combustible portion of the
+mould, and in many places cracking and disintegrating the rock beneath.
+The rains of the following autumn carried off much of the remaining
+soil, and the mountain side was nearly bare of wood for two or three
+years afterward. At length, a new crop of trees sprang up and grew
+vigorously, and the mountain is now thickly covered again. But the depth
+of mould and earth is too small to allow the trees to reach maturity.
+When they attain to the diameter of about six inches, they uniformly
+die, and this they will no doubt continue to do until the decay of
+leaves and wood on the surface, and the decomposition of the subjacent
+rock, shall have formed, perhaps hundreds of years hence, a stratum of
+soil thick enough to support a full-grown forest.
+
+[248] The growth of the white pine, on a good soil and in open ground,
+is rather rapid until it reaches the diameter of a couple of feet, after
+which it is much slower. The favorite habitat of this tree is light
+sandy earth. On this soil, and in a dense wood, it requires a century to
+attain the diameter of a yard. Emerson (_Trees of Massachusetts_, p.
+65), says that a pine of this species, near Paris, "thirty years
+planted, is eighty feet high, with a diameter of three feet." He also
+states that ten white pines planted at Cambridge, Massachusetts, in 1809
+or 1810, exhibited, in the winter of 1841 and 1842, an average of twenty
+inches diameter at the ground, the two largest measuring, at the height
+of three feet, four feet eight inches in circumference; and he mentions
+another pine growing in a rocky swamp, which, at the age of thirty-two
+years, "gave seven feet in circumference at the but, with a height of
+sixty-two feet six inches." This latter I suppose to be a seedling, the
+others _transplanted_ trees, which might have been some years old when
+placed where they finally grew.
+
+The following case came under my own observation: In 1824, a pine tree,
+so small that a young lady, with the help of a lad, took it up from the
+ground and carried it a quarter of a mile, was planted near a house in a
+town in Vermont. It was occasionally watered, but received no other
+special treatment. I measured this tree in 1860, and found it, at four
+feet from the ground, and entirely above the spread of the roots, two
+feet and four inches in diameter. It could not have been more than three
+inches through when transplanted, and must have increased its diameter
+twenty-five inches in thirty-six years.
+
+[249] WILLIAMS, _History of Vermont_, ii, p. 53. DWIGHT's _Travels_, iv,
+p. 21, and iii, p. 36. EMERSON, _Trees of Massachusetts_, p. 61. PARISH,
+_Life of President Wheelock_, p. 56.
+
+[250] The forest trees of the Northern States do not attain to extreme
+longevity in the dense woods. Dr. Williams found that none of the huge
+pines, the age of which he ascertained, exceeded three hundred and fifty
+or four hundred years, though he quotes a friend who thought he had
+noticed trees considerably older. The oak lives longer than the pine,
+and the hemlock spruce is perhaps equally long lived. A tree of this
+latter species, cut within my knowledge in a thick wood, counted four
+hundred and eighty-six, or, according to another observer, five hundred
+annual circles.
+
+Great luxuriance of animal and vegetable production is not commonly
+accompanied by long duration of the individual. The oldest men are not
+found in the crowded city; and in the tropics, where life is prolific
+and precocious, it is also short. The most ancient forest trees of which
+we have accounts have not been those growing in thick woods, but
+isolated specimens, with no taller neighbor to intercept the light and
+heat and air, and no rival to share the nutriment afforded by the soil.
+
+The more rapid growth and greater dimensions of trees standing near the
+boundary of the forest, are matters of familiar observation. "Long
+experience has shown that trees growing on the confines of the wood may
+be cut at sixty years of age as advantageously as others of the same
+species, reared in the depth of the forest, at a hundred and twenty. We
+have often remarked, in our Alps, that the trunk of trees upon the
+border of a grove is most developed or enlarged upon the outer or open
+side, where the branches extend themselves farthest, while the
+concentric circles of growth are most uniform in those entirely
+surrounded by other trees, or standing entirely alone."--A. and G.
+VILLA, _Necessita dei Boschi_, pp. 17, 18.
+
+[251] Caimi states that "a single flotation in the Valtelline in 1839,
+caused damages alleged to amount to more than $800,000, and actually
+appraised at $250,000."--_Cenni sulla Importanza e Coltura dei Boschi_,
+p. 65.
+
+[252] Most physicists who have investigated the laws of natural
+hydraulics maintain that, in consequence of direct obstruction and
+frictional resistance to the flow of the water of rivers along their
+banks, there is both an increased rapidity of current and an elevation
+of the water in the middle of the channel, so that a river presents
+always a convex surface. The lumbermen deny this. They affirm that,
+while rivers are rising, the water is highest in the middle of the
+channel, and tends to throw floating objects shoreward; while they are
+falling, it is lowest in the middle, and floating objects incline toward
+the centre. Logs, they say, rolled into the water during the rise, are
+very apt to lodge on the banks, while those set afloat during the
+falling of the waters keep in the current, and are carried without
+hindrance to their destination.
+
+Foresters and lumbermen, like sailors and other persons whose daily
+occupations bring them into contact, and often, into conflict, with
+great natural forces, have many peculiar opinions, not to say
+superstitions. In one of these categories we must rank the universal
+belief of lumbermen, that with a given head of water, and in a given
+number of hours, a sawmill cuts more lumber by night than by day. Having
+been personally interested in several sawmills, I have frequently
+conversed with sawyers on this subject, and have always been assured by
+them that their uniform experience established the fact that, other
+things being equal, the action of the machinery of sawmills is more
+rapid by night than by day. I am sorry--perhaps I ought to be
+ashamed--to say that my scepticism has been too strong to allow me to
+avail myself of my opportunities of testing this question by passing a
+night, watch in hand, counting the strokes of a millsaw. More
+unprejudiced, and I must add, very intelligent and credible persons have
+informed me that they have done so, and found the report of the sawyers
+abundantly confirmed. A land surveyor, who was also an experienced
+lumberman, sawyer, and machinist, a good mathematician and an exact
+observer, has repeatedly told me, that he had very often "timed"
+sawmills, and found the difference in favor of night work above thirty
+per cent. _Sed quaere._
+
+[253] For many instances of this sort, see BECQUEREL, _Des Climats,
+etc._, pp. 301-303. In 1664, the Swedes made an incursion into Jutland
+and felled a considerable extent of forest. After they retired, a survey
+of the damage was had, and the report is still extant. The number of
+trees cut was found to be 120,000, and as an account was kept of the
+numbers of each species of tree, the document is of interest in the
+history of the forest, as showing the relative proportions between the
+different trees which composed the wood. See VAUPELL. _Boegens
+Indvandring_, p. 35, and _Notes_, p. 55.
+
+[254] Since writing this paragraph, I have fallen upon--and that in a
+Spanish author--one of those odd coincidences of thought which every man
+of miscellaneous reading so often meets with. Antonio Ponz (_Viage de
+Espana_, i, prologo, p. lxiii), says: "Nor would this be so great an
+evil, were not some of them declaimers against _trees_, thereby
+proclaiming themselves, in some sort, enemies of the works of God, who
+gave us the leafy abode of Paradise to dwell in, where we should be even
+now sojourning, but for the first sin, which expelled us from it."
+
+I do not know at what period the two Castiles were bared of their woods,
+but the Spaniard's proverbial "hatred of a tree" is of long standing.
+Herrera vigorously combats this foolish prejudice; and Ponz, in the
+prologue to the ninth volume of his journey, says that many carried it
+so far as wantonly to destroy the shade and ornamental trees planted by
+the municipal authorities. "Trees," they contended, and still believe,
+"breed birds, and birds eat up the grain." Our author argues against the
+supposition of the "breeding of birds by trees," which, he says, is as
+absurd as to believe that an elm tree can yield pears; and he charitably
+suggests that the expression is, perhaps, a _maniere de dire_, a popular
+phrase, signifying simply that trees harbor birds.
+
+[255] Religious intolerance had produced similar effects in France
+at an earlier period. "The revocation of the edict of Nantes and
+the dragonnades occasioned the sale of the forests of the unhappy
+Protestants, who fled to seek in foreign lands the liberty of
+conscience which was refused to them in France. The forests were
+soon felled by the purchasers, and the soil in part brought under
+cultivation."'--BECQUEREL, _Des Climats, etc._, p. 303.
+
+[256] The American reader must be reminded that, in the language of the
+chase and of the English law, a "forest" is not necessarily a wood. Any
+large extent of ground, withdrawn from cultivation, reserved for the
+pleasures of the chase, and allowed to clothe itself with a spontaneous
+growth, serving as what is technically called "cover" for wild animals,
+is, in the dialects I have mentioned, a forest. When, therefore, the
+Norman kings afforested the grounds referred to in the text, it is not
+to be supposed that they planted them with trees, though the protection
+afforded to them by the game laws would, if cattle had been kept out,
+soon have converted them into real woods.
+
+[257] _Histoire des Paysans_, ii, p. 190. The work of Bonnemere is of
+great value to those who study the history of mediaeval Europe from a
+desire to know its real character, and not in the hope of finding
+apparent facts to sustain a false and dangerous theory. Bonnemere is one
+of the few writers who, like Michelet, have been honest enough and bold
+enough to speak the truth with regard to the relations between the
+church and the people in the Middle Ages.
+
+[258] It is painful to add that a similar outrage was perpetrated a very
+few years ago, in one of the European states, by a prince of a family
+now dethroned. In this case, however, the prince killed the trespasser
+with his own hand, his sergeants refusing to execute his mandate.
+
+[259] GUILLAUME DE NANGIS, as quoted in the notes to JOINVILLE,
+_Nouvelle Collection des Memoires, etc._, par Michaud et Poujoulat,
+premiere serie, i, p. 335.
+
+Persons acquainted with the character and influence of the mediaeval
+clergy will hardly need to be informed that the ten thousand livres
+never found their way to the royal exchequer. It was easy to prove to
+the simple-minded king that, as the profits of sin were a monopoly of
+the church, he ought not to derive advantage from the commission of a
+crime by one of his subjects; and the priests were cunning enough both
+to secure to themselves the amount of the fine, and to extort from Louis
+large additional grants to carry out the purposes to which they devoted
+the money. "And though the king did take the moneys," says the
+chronicler, "he put them not into his treasury, but turned them into
+good works; for he builded therewith the maison-Dieu of Pontoise, and
+endowed the same with rents and lands; also the schools and the
+dormitory of the friars preachers of Paris, and the monastery of the
+Minorite friars."
+
+[260] _Histoire des Paysans_, ii, p. 200.
+
+[261] The following details from Bonnemere will serve to give a more
+complete idea of the vexatious and irritating nature of the game laws of
+France. The officers of the chase went so far as to forbid the pulling
+up of thistles and weeds, or the mowing of any unenclosed ground before
+St. John's day [24th June], in order that the nests of game birds might
+not be disturbed. It was unlawful to fence-in any grounds in the plains
+where royal residences were situated; thorns were ordered to be planted
+in all fields of wheat, barley, or oats, to prevent the use of ground
+nets for catching the birds which consumed, or were believed to consume,
+the grain, and it was forbidden to cut or pull stubble before the first
+of October, lest the partridge and the quail might be deprived of their
+cover. For destroying the eggs of the quail, a fine of one hundred
+livres was imposed for the first offence, double that amount for the
+second, and for the third the culprit was flogged and banished for five
+years to a distance of six leagues from the forest.--_Histoire des
+Paysans_, ii, p. 202, text and notes.
+
+Neither these severe penalties, nor any provisions devised by the
+ingenuity of modern legislation, have been able effectually to repress
+poaching. "The game laws," says Clave, "have not delivered us from the
+poachers, who kill twenty times as much game as the sportsmen. In the
+forest of Fontainebleau, as in all those belonging to the state,
+poaching is a very common and a very profitable offence. It is in vain
+that the gamekeepers are on the alert night and day, they cannot prevent
+it. Those who follow the trade begin by carefully studying the habits of
+the game. They will lie motionless on the ground, by the roadside or in
+thickets, for whole days, watching the paths most frequented by the
+animals," &c.--_Revue des Deux Mondes_, Mai, 1863, p. 160.
+
+The writer adds many details on this subject, and it appears that, as
+there are "beggars on horseback" in South America, there are poachers in
+carriages in France.
+
+[262] "Whole trees were sacrificed for the most insignificant purposes;
+the peasants would cut down two firs to make a single pair of wooden
+shoes."--MICHELET, as quoted by CLAVE, _Etudes_, p. 24.
+
+A similar wastefulness formerly prevailed in Russia, though not from the
+same cause. In St. Pierre's time, the planks brought to St. Petersburg
+were not sawn, but hewn with the axe, and a tree furnished but a single
+plank.
+
+[263] "A hundred and fifty paces from my house is a hill of drift sand,
+on which stood a few scattered pines. _Pinus sylvestris_, and
+_Sempervivum tectorum_ in abundance, _Statice armeria_, _Ammone
+vernalis_, _Dianthus carthusianorum_, with other sand plants, were
+growing there. I planted the hill with a few birches, and all the plants
+I have mentioned completely disappeared, though there were many naked
+spots of sand between the trees. It should be added, however, that the
+hillock is more thickly wooded than before. * * * It seems then that
+_Sempervivum tectorum_, &c., will not bear the neighborhood of the
+birch, though growing well near the _Pinus sylvestris_. I have found the
+large red variety of _Agaricus deliciosus_ only among the roots of the
+pine; the greenish-blue _Agaricus deliciosus_ among alder roots, but not
+near any other tree. Birds have their partialities among trees and
+shrubs. The _Silviae_ prefer the _Pinus Larix_ to other trees. In my
+garden this _Pinus_ is never without them, but I never saw a bird perch
+on _Thuja occidenialis_ or _Juniperus sabina_, although the thick
+foliage of these latter trees affords birds a better shelter than the
+loose leafage of other trees. Not even a wren ever finds its way to one
+of them. Perhaps the scent of the _Thuja_ and the _Juniperus_ is
+offensive to them. I have spoiled one of my meadows by cutting away the
+bushes. It formerly bore grass four feet high, because many
+umbelliferous plants, such as _Heracleum spondylium_, _Spiraea ulmaria_,
+_Laserpitium latifolia_, &c., grew in it. Under the shelter of the
+bushes these plants ripened and bore seed, but they gradually
+disappeared as the shrubs were extirpated, and the grass now does not
+grow to the height of more than two feet, because it is no longer
+obliged to keep pace with the umbellifera which flourished among it."
+See a paper by J. G. BUeTTNER, of Kurland, in BERGHAUS' _Geographisches
+Jahrbuch_, 1852, No. 4, pp. 14, 15.
+
+These facts are interesting as illustrating the multitude of often
+obscure conditions upon which the life or vigorous growth of smaller
+organisms depends. Particular species of truffles and of mushrooms are
+found associated with particular trees, without being, as is popularly
+supposed, parasites deriving their nutriment from the dying or dead
+roots of those trees. The success of Rousseau's experiments seem
+decisive on this point, for he obtains larger crops of truffles from
+ground covered with young seedling oaks than from that filled with roots
+of old trees. See an article on Mont Ventoux, by Charles Martins, in the
+_Revue des Deux Mondes_, Avril, 1863, p. 626.
+
+It ought to be much more generally known than it is that most, if not,
+all mushrooms, even of the species reputed poisonous, may be rendered
+harmless and healthful as food by soaking them for two hours in
+acidulated or salt water. The water requires two or three spoonfuls of
+vinegar or two spoonfuls of gray salt to the quart, and a quart of water
+is enough for a pound of sliced mushrooms. After thus soaking, they are
+well washed in fresh water, thrown into cold water, which is raised to
+the boiling point, and, after remaining half an hour, taken out and
+again washed. Gerard, to prove that "crumpets is wholesome," ate one
+hundred and seventy-five pounds of the most poisonous mushrooms thus
+prepared, in a single month, fed his family _ad libitum_ with the same,
+and finally administered them, in heroic doses, to the members of a
+committee appointed by the Council of Health of the city of Paris. See
+FIGUIER, _L'Annee Scientifique_, 1862, pp. 353, 384. See _Appendix_, No.
+31.
+
+It has long been known that the Russian peasantry eat, with impunity,
+mushrooms of species everywhere else regarded as very poisonous. Is it
+not probable that the secret of rendering them harmless--which was known
+to Pliny, though since forgotten in Italy--is possessed by the rustic
+Muscovites?
+
+[264] _Physikalische Geographie_, p. 486.
+
+[265] _Origin of Species_, American edition, p. 69.
+
+[266] Writers on vegetable physiology record numerous instances where
+seeds have grown after lying dormant for ages. The following cases,
+mentioned by Dr. Dwight (_Travels_, ii, pp. 438, 439), may be new to
+many readers:
+
+"The lands [in Panton, Vermont], which have here been once cultivated,
+and again permitted to lie waste for several years, yield a rich and
+fine growth of hickory [_Carya porcina_]. Of this wood there is not, I
+believe, a single tree in any original forest within fifty miles from
+this spot. The native growth was here white pine, of which I did not see
+a single stem in a whole grove of hickory."
+
+The hickory is a walnut, bearing a fruit too heavy to be likely to be
+carried fifty miles by birds, and besides, I believe it is not eaten by
+any bird indigenous to Vermont.
+
+"A field, about five miles from Northampton, on an eminence called Rail
+Hill, was cultivated about a century ago. The native growth here, and in
+all the surrounding region, was wholly oak, chestnut, &c. As the field
+belonged to my grandfather, I had the best opportunity of learning its
+history. It contained about five acres, in the form of an irregular
+parallelogram. As the savages rendered the cultivation dangerous, it was
+given up. On this ground there sprang up a grove of white pines covering
+the field and retaining its figure exactly. So far as I remember, there
+was not in it a single oak or chestnut tree. * * * There was not a
+single pine whose seeds were, or, probably, had for ages been,
+sufficiently near to have been planted on this spot. The fact that these
+white pines covered this field exactly, so as to preserve both its
+extent and its figure, and that there were none in the neighborhood, are
+decisive proofs that cultivation brought up the seeds of a former forest
+within the limits of vegetation, and gave them an opportunity to
+germinate."
+
+[267] Quaint old Valvasor had observed the subduing influence of
+nature's solitudes. In describing the lonely Canker-Thal, which, though
+rocky, was in his time well wooded with "fir, larches, beeches, and
+other trees," he says: "Gladsomeness and beauty, which dwell in many
+valleys, may not be looked for there. The journey through it is
+cheerless, melancholy, wearisome, and serveth to temper and mortify
+over-joyousness of thought. * * * In sum it is a very wild, wherein the
+wildness of human pride doth grow tame."--_Ehre der Crain_, i, p. 136,
+b.
+
+[268] Valvasor says, in the same paragraph from which I have just
+quoted, "In my many journeys through this valley, I did never have sight
+of so much as a single bird."
+
+[269] Smela, in the government of Kiew, has, for some years, not
+suffered at all from the locusts, which formerly came every year in vast
+swarms, and the curculio, so injurious to the turnip crops, is less
+destructive there than in other parts of the province. This improvement
+is owing partly to the more thorough cultivation of the soil, partly to
+the groves which are interspersed among the plough lands. * * * When in
+the midst of the plains woods shall be planted and filled with
+insectivorous birds, the locusts will cease to be a plague and a terror
+to the farmer.--RENTZSCH, _Der Wald_, pp. 45, 46.
+
+[270] England is, I believe, the only country where private enterprise
+has pursued sylviculture on a really great scale, though admirable
+examples have been set in many others on both sides of the Atlantic. In
+England the law of primogeniture, and other institutions and national
+customs which tend to keep large estates long undivided and in the same
+line of inheritance, the wealth of the landholders, and the difficulty
+of finding safe and profitable investments of capital, combine to afford
+encouragements for the plantation of forests, which nowhere else exist
+in the same degree. The climate of England, too, is very favorable to
+the growth of forest trees, though the character of surface secures a
+large part of the island from the evils which have resulted from the
+destruction of the woods elsewhere, and therefore their restoration is a
+matter of less geographical importance in England than on the Continent.
+
+[271] The preservation of the woods on the eastern frontier of France,
+as a kind of natural abattis, is also recognized by the Government of
+that country as an important measure of military defence, though there
+have been conflicting opinions on the subject.
+
+[272] Let us take the supply of timber for railroad ties. According to
+Clave (p. 248), France has 9,000 kilometres of railway in operation,
+7,000 in construction, half of which is built with a double track.
+Adding turnouts and extra tracks at stations, the number of ties
+required for a single track is stated at 1,200 to the kilometre, or, as
+Clave computes, for the entire network of France, 58,000,000. As the
+schoolboys say, "this sum does not prove;" for 16,000 + 8,000 for the
+double track halfway = 24,000, and 24,000 x 1,200 = 28,800,000.
+According to Bigelow (_Les Etats Unis en 1863_, p. 439), the United
+States had in operation or construction on the first of January, 1862,
+51,000 miles, or about 81,000 kilometres of railroad, and the military
+operations of the present civil war are rapidly extending the system.
+Allowing the same proportion as in France, the American railroads
+required 97,200,000 ties in 1862. The consumption of timber in Europe
+and America during the present generation, occasioned by this demand,
+has required the sacrifice of many hundred thousand acres of forest, and
+if we add the quantity employed for telegraph posts, we have an amount
+of destruction, for entirely new purposes, which is really appalling.
+
+The consumption of wood for lucifer matches is enormous, and I have
+heard of several instances where tracts of pine forest, hundreds and
+even thousands of acres in extent, have been purchased and felled,
+solely to supply timber for this purpose.
+
+The demand for wood for small carvings and for children's toys is
+incredibly large. Rentzsch states the export of such objects from the
+town of Sonneberg alone to have amounted, in 1853, to 60,000 centner, or
+three thousand tons' weight.--_Der Wald_, p. 68. See _Appendix_, No. 33.
+
+The importance of so managing the forest that it may continue
+indefinitely to furnish an adequate supply of material for naval
+architecture is well illustrated by some remarks of the same author in
+the valuable little work just cited. He suggests that the prosperity of
+modern England is due, in no small degree, to the supplies of wood and
+other material for building and equipping ships, received from the
+forests of her colonies and of other countries with which she has
+maintained close commercial relations, and he adds: "Spain, which by her
+position seemed destined for universal power, and once, in fact,
+possessed it, has lost her political rank, because during the unwise
+administration of the successors of Philip II, the empty exchequer could
+not furnish the means of building new fleets; for the destruction of the
+forests had raised the price of timber above the resources of the
+state."--_Der Wald_, p. 63.
+
+The market price of timber, like that of all other commodities, may be
+said, in a general way, to be regulated by the laws of demand and
+supply, but it is also controlled by those seemingly unrelated accidents
+which so often disappoint the calculations of political economists in
+other branches of commerce. A curious case of this sort is noticed by
+CERINI, _Dell' Impianto e Conservazione dei Boschi_, p. 17: "In the
+mountains on the Lago Maggiore, in years when maize is cheap, the
+woodcutters can provide themselves with corn meal enough for a week by
+three days' labor, and they refuse to work the remaining four. Hence the
+dealers in wood, not being able to supply the demand, for want of
+laborers, are obliged to raise the price for the following season, both
+for timber and for firewood; so that a low price of grain occasions a
+high price of building lumber and of fuel. The consequence is, that
+though the poor have supplied themselves cheaply with food, they must
+pay dear for firewood, and they cannot get work, because the high price
+of lumber has discouraged repairs and building, the expense of which
+landed proprietors cannot undertake when their incomes have been reduced
+by sales of grain at low rates, and hence there is not demand enough for
+lumber to induce the timber merchants to furnish employment to the
+woodmen."
+
+[273] Besides the substitution of iron for wood, a great saving of
+consumption of this latter material has been effected by the revival of
+ancient methods of increasing its durability, and the invention of new
+processes for the same purpose. The most effectual preservative yet
+discovered for wood employed on land, is sulphate of copper, a solution
+of which is introduced into the pores of the wood while green, by
+soaking, by forcing-pumps, or, most economically, by the simple pressure
+of a column of the fluid in a small pipe connected with the end of the
+piece of timber subjected to the treatment. Clave (_Etudes Forestieres_,
+pp. 240-249) gives an interesting account of the various processes
+employed for rendering wood imperishable, and states that railroad ties
+injected with sulphate of copper in 1846, were found absolutely
+unaltered in 1855; and telegraphic posts prepared two years earlier, are
+now in a state of perfect preservation.
+
+For many purposes, the method of injection is too expensive, and some
+simpler process is much to be desired. The question of the proper time
+of felling timber is not settled, and the best modes of air, water, and
+steam seasoning are not yet fully ascertained. Experiments on these
+subjects would be well worth the patronage of governments in new
+countries, where they can be very easily made, without the necessity of
+much waste of valuable material, and without expensive arrangements for
+observation.
+
+The practice of stripping living trees of their bark some years before
+they are felled, is as old as the time of Vitruvius, but is much less
+followed than it deserves, partly because the timber of trees so treated
+inclines to crack and split, and partly because it becomes so hard as to
+be wrought with considerable difficulty.
+
+In America, economy in the consumption of fuel has been much promoted by
+the substitution of coal for wood, the general use of stoves both for
+wood and coal, and recently by the employment of anthracite in the
+furnaces of stationary and locomotive steam-engines. All the objections
+to the use of anthracite for this latter purpose appear to have been
+overcome, and the improvements in its combustion have been attended with
+a great pecuniary saving, and with much advantage to the preservation of
+the woods.
+
+The employment of coal has produced a great reduction in the consumption
+of fire wood in Paris. In 1815, the supply of fire wood for the city
+required 1,200,000 steres, or cubic metres; in 1859, it had fallen to
+501,805, while, in the mean time, the consumption of coal had risen from
+600,000 to 432,000,000 metrical quintals. See CLAVE, _Etudes_, p. 212.
+
+I think there must be some error in this last sum, as 432 millions of
+metrical quintals would amount to 43 millions of tons, a quantity which
+it is difficult to suppose could be consumed in the city of Paris. The
+price of fire wood has scarcely advanced at all in Paris for half a
+century, though that of timber generally has risen enormously.
+
+[274] In the first two years of the present civil war in the United
+States, twenty-eight thousand walnut trees were felled to supply a
+single European manufactory of gunstocks for the American market.
+
+[275] Among the indirect proofs of the comparatively recent existence of
+extensive forests in France, may be mentioned the fact, that wolves were
+abundant, not very long since, in parts of the empire where there are
+now neither wolves nor woods to shelter them. Arthur Young more than
+once speaks of the "innumerable multitudes" of these animals which
+infested France in 1789, and George Sand states, in the _Histoire de ma
+Vie_, that some years after the restoration of the Bourbons, they chased
+travellers on horseback in the Southern provinces, and literally knocked
+at the doors of her father-in-law's country seat.
+
+[276] In the _Recepte Veritable_, Palissy having expressed his
+indignation at the folly of men in destroying the woods, his
+interlocutor defends the policy of felling them, by citing the example
+of "divers bishops, cardinals, priors, abbots, monkeries, and chapters,
+which, by cutting their woods, have made three profits," the sale of the
+timber, the rent of the ground, and the "good portion" they received of
+the grain grown by the peasants upon it. To this argument, Palissy
+replies: "I cannot enough detest this thing, and I call it not an error,
+but a curse and a calamity to all France; for when forests shall be cut,
+all arts shall cease, and they which practise them shall be driven out
+to eat grass with Nebuchadnezzar and the beasts of the field. I have
+divers times thought to set down in writing the arts which shall perish
+when there shall be no more wood; but when I had written down a great
+number, I did perceive that there could be no end of my writing, and
+having diligently considered, I found there was not any which could be
+followed without wood." * * "And truly I could well allege to thee a
+thousand reasons, but 'tis so cheap a philosophy, that the very chamber
+wenches, if they do but think, may see that without wood, it is not
+possible to exercise any manner of human art or cunning."--_[OE]uvres
+de_ BERNARD PALISSY, p. 89.
+
+[277] Since writing the above paragraph, I have found the view I have
+taken of this point confirmed by the careful investigations of Rentzsch,
+who estimates the proper proportion of woodland to entire surface at
+twenty-three per cent. for the interior of Germany, and supposes that
+near the coast, where the air is supplied with humidity by evaporation
+from the sea, it might safely be reduced to twenty per cent. See
+Rentzsch's very valuable prize essay, _Der Wald im Haushalt der Natur
+und der Volkswirthschaft_, cap. viii.
+
+The due proportion in France would considerably exceed that for the
+German States, because France has relatively more surface unfit for any
+growth but that of wood, because the form and geological character of
+her mountains expose her territory to much greater injury from torrents,
+and because at least her southern provinces are more frequently visited
+both by extreme drought and by deluging rains.
+
+[278] _Etudes sur l'Economie Forestiere_, p. 261. Clave adds (p. 262):
+"The Russian forests are very unequally distributed through the
+territory of this vast empire. In the north they form immense masses,
+and cover whole provinces, while in the south they are so completely
+wanting that the inhabitants have no other fuel than straw, dung,
+rushes, and heath." * * * "At Moscow, firewood costs thirty per cent.
+more than at Paris, while, at the distance of a few leagues, it sells
+for a tenth of that price."
+
+This state of things is partly due to the want of facilities of
+transportation, and some parts of the United States are in a similar
+condition. During a severe winter, six or seven years ago, the sudden
+freezing of the canals and rivers, before a large American town had
+received its usual supply of fuel, occasioned an enormous rise in the
+price of wood and coal, and the poor suffered severely for want of it.
+Within a few hours of the city were large forests and an abundant stock
+of firewood felled and prepared for burning. This might easily have been
+carried to town by the railroads which passed through the woods; but the
+managers of the roads refused to receive it as freight, because the
+opening of a new market for wood might raise the price of the fuel they
+employed for their locomotives.
+
+Hohenstein, who was long professionally employed as a forester in
+Russia, describes the consequences of the general war upon the woods in
+that country as already most disastrous, and as threatening still more
+ruinous evils. The river Volga, the life artery of Russian internal
+commerce, is drying up from this cause, and the great Muscovite plains
+are fast advancing to a desolation like that of Persia.--_Der Wald_, p.
+223.
+
+The level of the Caspian Sea is eighty-three feet lower than that of the
+Sea of Azoff, and the surface of Lake Aral is fast sinking. Von Baer
+maintains that the depression of the Caspian was produced by a sudden
+subsidence, from geological causes, and not gradually by excess of
+evaporation over supply. See _Kaspische Studien_, p. 25. But this
+subsidence diminished the area and consequently the evaporation of that
+sea, and the rivers which once maintained its ancient equilibrium ought
+to raise it to its former level, if their own flow had not been
+diminished. It is, indeed, not proved that the laying bare of a wooded
+country diminishes the total annual precipitation upon it; but it is
+certain that the summer evaporation from the surface of a champaign
+region, like that through which the Volga, its tributaries, and the
+feeders of Lake Aral flow, is increased by the removal of its woods.
+Hence, though as much rain may still fall in the valleys of those rivers
+as when their whole surface was covered with forests, a less quantity of
+water may be delivered by them since their basins were cleared, and
+therefore the present condition of the inland waters in question may be
+due to the removal of the forests in their basins.
+
+[279] Rentzsch _(Der Wald, etc._, pp. 123, 124) states the proportions
+of woodland in different European countries as follows:
+
+ ---------------+----------+-----------
+ | |Acres per
+ | Per cent.| head of
+ | |population.
+ ---------------+----------+-----------
+ Germany | 26.58 | 0.6638
+ Great Britain | 5. | 0.1
+ France | 16.79 | 0.3766
+ Russia | 30.90 | 4.28
+ Sweden | 60. | 8.55
+ Norway | 66. | 24.61
+ Denmark | 5.50 | 0.22
+ Switzerland | 15. | 0.396
+ Holland | 7.10 | 0.12
+ Belgium | 18.52 | 0.186
+ Spain | 5.52 | 0.291
+ Portugal | 4.40 | 0.182
+ Sardinia | 12.29 | 0.223
+ Naples | 9.43 | 0.138
+ ---------------+----------+-----------
+
+Probably no European countries can so well dispense with the forests, in
+their capacity of conservative influences, as England and Ireland. Their
+insular position and latitude secure an abundance of atmospheric
+moisture, and the general inclination of surface is not such as to
+expose it to special injury from torrents. The due proportion of
+woodland in England and Ireland is, therefore, almost purely an
+economical question, to be decided by the comparative direct pecuniary
+return from forest growth, pasturage, and plough land.
+
+In Scotland, where the country is for the most part more broken and
+mountainous, the general destruction of the forests has been attended
+with very serious evils, and it is in Scotland that many of the most
+extensive British forest plantations have now been formed. But although
+the inclination of surface in Scotland is rapid, the geological
+constitution of the soil is not of a character to promote such
+destructive degradation by running water as in Southern France, and it
+has not to contend with the parching droughts by which the devastations
+of the torrents are rendered more injurious in that part of the French
+empire.
+
+In giving the proportion of woodland to population, I compute Rentzsch's
+Morgen at .3882 of an English acre, because I find, by Alexander's most
+accurate and valuable Dictionary of Weights and Measures, that this is
+the value of the Dresden Morgen, and Rentzsch is a Saxon writer. In the
+different German States, there are more than twenty different land
+measures known by the name of Morgen, varying from about one third of an
+acre to more than three acres in value. When will the world be wise
+enough to unite in adopting the French metrical and monetary systems? As
+to the latter, never while Christendom continues to be ruled by money
+changers, who can compel you to part with your sovereigns in France at
+twenty-five francs, and in England to accept fifteen shillings for your
+napoleons. I speak as a sufferer. _Experto crede Roberto._
+
+[280] According to the maxims of English jurisprudence, the common law
+consists of general customs so long established that "the memory of man
+runneth not to the contrary." In other words, long custom makes law. In
+new countries, the change of circumstances creates new customs, and, in
+time, new law, without the aid of legislation. Had the American
+colonists observed a more sparing economy in the treatment of their
+woods, a new code of customary forest law would have sprung up and
+acquired the force of a statute. Popular habit was fast elaborating the
+fundamental principles of such a code, when the rapid increase in the
+value of timber, in consequence of the reckless devastation of the
+woodlands, made it the interest of the proprietors to interfere with
+this incipient system of forest jurisprudence, and appeal to the rules
+of English law for the protection of their woods. The courts have
+sustained these appeals, and forest property is now legally as
+inviolable as any other, though common opinion still combats the course
+of judicial decision on such questions.
+
+In the United States, swarms of honey bees, on leaving the parent hive,
+often take up their quarters in hollow trees in the neighboring woods.
+By the early customs of New England, the finder of a "bee tree" on the
+land of another owner was regarded as entitled to the honey by right of
+discovery; and as a necessary incident of that right, he might cut the
+tree, at the proper season, without asking permission of the proprietor
+of the soil. The quantity of "wild honey" in a tree was often large, and
+"bee hunting" was so profitable that it became almost a regular
+profession. The "bee hunter" sallied forth with a small box containing
+honey and a little vermilion. The bees which were attracted by the honey
+marked themselves with the vermilion, and hence were more readily
+followed in their homeward flight, and recognized when they returned a
+second time for booty. When loaded with spoil, this insect returns to
+his hive by the shortest route, and hence a straight line is popularly
+called in America a "bee line." By such a line, the hunter followed the
+bees to their sylvan hive, marked the tree with his initials, and
+returned to secure his prize in the autumn. When the right of the "bee
+hunter" was at last disputed by the land proprietors, it was with
+difficulty that judgments could be obtained, in inferior courts, in
+favor of the latter, and it was only after repeated decisions of the
+higher legal tribunals that the superior right of the owner of the soil
+was at last acquiesced in.
+
+[281] _Etude sur le Reboisement des Montagnes_, p. 5.
+
+[282] "In America," says Clave (p. 124, 125), "where there is a vast
+extent of land almost without pecuniary value, but where labor is dear
+and the rate of interest high, it is profitable to till a large surface
+at the least possible cost; _extensive_ cultivation is there the most
+advantageous. In England, France, and Germany, where every corner of
+soil is occupied, and the least bit of ground is sold at a high price,
+but where labor and capital are comparatively cheap, it is wisest to
+employ _intensive_ cultivation. * * * All the efforts of the cultivator
+ought to be directed to the obtaining of a given result with the least
+sacrifice, and there is equally a loss to the commonwealth if the
+application of improved agricultural processes be neglected where
+they are advantageous, or if they be employed where they are not
+required. * * * In this point of view, sylviculture must follow the same
+laws as agriculture, and, like it, be modified according to the
+economical conditions of different states. In countries abounding in
+good forests, and thinly peopled, elementary and cheap methods must be
+pursued; in civilized regions, where a dense population requires that
+the soil shall be made to produce all it can yield, the regular
+artificial forest, with all the processes that science teaches, should
+be cultivated. It would be absurd to apply to the endless woods of
+Brazil and of Canada the method of the Spessart by "double stages," and
+not less so in our country, where every yard of ground has a high value,
+to leave to nature the task of propagating trees, and to content
+ourselves with cutting, every twenty or twenty-five years, the meagre
+growths that chance may have produced."
+
+[283] It is often laid down as a universal law, that the wood of trees
+of slow vegetation is superior to that of quick growth. This is one of
+those commonplaces by which men love to shield themselves from the labor
+of painstaking observation. It has, in fact, so many exceptions, that it
+may be doubted whether it is in any sense true. Most of the cedars are
+slow of growth; but while the timber of some of them is firm and
+durable, that of others is light, brittle, and perishable. The hemlock
+spruce is slower of growth than the pines, but its wood is of very
+little value. The pasture oak and beech show a breadth of grain--and, of
+course, an annual increment--twice as great as trees of the same species
+grown in the woods; and the American locust, _Robinia pseudacacia_, the
+wood of which is of extreme toughness and durability, is, of all trees
+indigenous to Northeastern America, by far the most rapid in growth.
+
+As an illustration of the mutual interdependence of the mechanic arts, I
+may mention that in Italy, where stone, brick, and plaster are almost
+the only materials used in architecture, and where the "hollow ware"
+kitchen implements are of copper or of clay, the ordinary tools for
+working wood are of a very inferior description, and the locust timber
+is found too hard for their temper. Southey informs us, in "Espriella's
+Letters," that when a small quantity of mahogany was brought to England,
+early in the last century, the cabinetmakers were unable to use it, from
+the defective temper of their tools, until the demand for furniture from
+the new wood compelled them to improve the quality of their implements.
+In America, the cheapness of wood long made it the preferable material
+for almost all purposes to which it could by any possibility be applied.
+The mechanical cutlery and artisans' tools of the United States are of
+admirable temper, finish, and convenience, and no wood is too hard, or
+otherwise too refractory, to be wrought with great facility, both by
+hand tools and by the multitude of ingenious machines which the
+Americans have invented for this purpose.
+
+[284] _Etudes Forestieres_, p. 7.
+
+[285] _Etudes Forestieres_, p. 7.
+
+[286] For very full catalogues of American forest trees, and remarks on
+their geographical distribution, consult papers on the subject by Dr. J.
+G. Cooper, in the Report of the Smithsonian Institution for 1858, and
+the Report of the United States Patent Office, Agricultural Division,
+for 1860.
+
+[287] Although Spenser's catalogue of trees occurs in the first canto of
+the first book of the "Faery Queene"--the only canto of that exquisite
+poem actually read by most students of English literature--it is not so
+generally familiar as to make the quotation of it altogether
+superfluous:
+
+VII.
+
+ Enforst to seeke some covert nigh at hand,
+ A shadie grove not farr away they spide,
+ That promist ayde the tempest to withstand;
+ Whose loftie trees, yelad with sommers pride,
+ Did spred so broad, that heavens light did hide,
+ Not perceable with power of any starr:
+ And all within were pathes and alleies wide,
+ With footing worne, and leading inward farr;
+ Faire harbour that them seems; so in they entred ar.
+
+VIII.
+
+ And foorth they passe, with pleasure forward led,
+ Joying to heare the birdes sweete harmony,
+ Which therein shrouded from the tempest dred,
+ Seemd in their song to scorne the cruell sky.
+ Much can they praise the trees so straight and hy,
+ The sayling pine; the cedar stout and tall;
+ The vine-propp elm; the poplar never dry;
+ The builder oake, sole king of forrests all;
+ The aspine good for staves; the cypresse funerall;
+
+IX.
+
+ The laurell, meed of mightie conquerours
+ And poets sage; the firre that weepeth still;
+ The willow, worne of forlorn paramours;
+ The eugh, obedient to the benders will;
+ The birch for shaftes; the sallow for the mill;
+ The mirrhe sweete-bleeding in the bitter wound;
+ The warlike beech; the ash for nothing ill;
+ The fruitfull olive; and the platane round;
+ The carver holme; the maple seeldom inward sound.
+
+
+[288] The walnut is a more valuable tree than is generally supposed. It
+yields one third of the oil produced in France, and in this respect
+occupies an intermediate position between the olive of the south, and
+the oleaginous seeds of the north. A hectare (about two and a half
+acres), will produce nuts to the value of five hundred francs a year,
+which cost nothing but the gathering. Unfortunately, its maturity must
+be long waited for, and more nut-trees are felled than planted. The
+demand for its wood in cabinet work is the principal cause of its
+destruction. See LAVERGNE, _Economie Rurale de la France_, p. 253.
+
+According to Cosimo Ridolfi (Lezioni Orali, ii. p. 424), France obtains
+three times as much oil from the walnut as from the olive, and nearly as
+much as from all oleaginous seeds together. He states that the walnut
+bears nuts at the age of twenty years, and yields its maximum product at
+seventy, and that a hectare of ground, with thirty trees, or twelve to
+the acre, is equal to a capital of twenty-five hundred francs.
+
+The nut of this tree is known in the United States as the "English
+walnut." The fruit and the wood much resemble those of the American
+black walnut, _Juglans nigra_, but for cabinet work the American is the
+more beautiful material, especially when the large knots are employed.
+The timber of the European species, when straight grained, and _clear_,
+or free from knots, is, for ordinary purposes, better than that of the
+American black walnut, but bears no comparison with the wood of the
+hickory, when strength combined with elasticity is required, and its nut
+is very inferior in taste to that of the shagbark, as well as to the
+butternut, which it somewhat resembles.
+
+"The chestnut is more valuable still, for it produces on a sterile soil,
+which, without it, would yield only ferns and heaths, an abundant
+nutriment for man."--LAVERGNE, _Economie Rurale de la France_, p. 253.
+
+I believe the varieties developed by cultivation are less numerous in
+the walnut than in the chestnut, which latter tree is often grafted in
+Southern Europe.
+
+[289] This fir is remarkable for its tendency to cicatrize or heal over
+its stumps, a property which it possesses in common with some other
+firs, the maritime pine, and the European larch. When these trees grow
+in thick clumps, their roots are apt to unite by a species of natural
+grafting, and if one of them be felled, although its own proper rootlets
+die, the stump may continue, sometimes for a century, to receive
+nourishment from the radicles of the surrounding trees, and a dome of
+wood and bark of considerable thickness be formed over it. The
+cicatrization is, however, only apparent, for the entire stump, except
+the outside ring of annual growth, soon dies, and even decays within its
+covering, without sending out new shoots.
+
+[290] At the age of twelve or fifteen years, the cork tree is stripped
+of its outer bark for the first time. This first yield is of inferior
+quality, and is employed for floats for nets and buoys, or burnt for
+lampblack. After this, a new layer of cork, an inch or an inch and a
+quarter in thickness, is formed about once in ten years, and is removed
+in large sheets without injury to the tree, which lives a hundred and
+fifty years or more. According to Clave (p. 252), the annual product of
+a forest of cork oaks is calculated at about 660 kilogrammes, worth 150
+francs, to the hectare, which, deducting expenses, leaves a profit of
+100 francs. This is about equal to 250 pound weight, and eight dollars
+profit to the acre. The cork oaks of the national domain in Algeria
+cover about 500,000 acres, and are let to individuals at rates which are
+expected, when the whole is rented, to yield to the state a revenue of
+about $2,000,000.
+
+George Sand, in the _Histoire de ma Vie_, speaks of the cork forests in
+Southern France as among the most profitable of rural possessions, and
+states, what I do not remember to have seen noticed elsewhere, that
+Russia is the best customer for cork. The large sheets taken from the
+trees are slit into thin plates, and used to line the walls of
+apartments in that cold climate.
+
+[291] The walnut, the chestnut, the apple, and the pear are common to
+the border between the countries I have mentioned, but the range of the
+other trees is bounded by the Alps, and by a well-defined and sharply
+drawn line to the west of those mountains. I cannot give statistical
+details as to the number of any of the trees in question, or as to the
+area they would cover if brought together in a given country. From some
+peculiarity in the sky of Europe, cultivated plants will thrive, in
+Northern Italy, in Southern France, and even in Switzerland, under a
+depth of shade where no crop, not even grass, worth harvesting, would
+grow in the United States with an equally high summer temperature. Hence
+the cultivation of all these trees is practicable in Europe to a greater
+extent than would be supposed reconcilable with the interests of
+agriculture. Some idea of the importance of the olive orchards may be
+formed from the fact that Sicily alone, an island scarcely exceeding
+10,000 square miles in area, of which one third at least is absolutely
+barren, has exported to the single port of Marseilles more than
+2,000,000 pounds weight of olive oil per year, for the last twenty
+years.
+
+[292] It is hard to say how far the peculiar form of the graceful crown
+of this pine is due to pruning. It is true that the extremities of the
+topmost branches are rarely lopped, but the lateral boughs are almost
+uniformly removed to a very considerable height, and it is not
+improbable that the shape of the top is thereby affected.
+
+[293] Besides this, in a country so diversified in surface--I wish we
+could with the French say _accidented_--as Italy with the exception of
+the champaign region drained by the Po, every new field of view requires
+either an extraordinary _coup d'[oe]il_ in the spectator, or a long
+study, in order to master its relief, its plans, its salient and
+retreating angles. In summer, the universal greenery confounds light and
+shade, distance and foreground; and though the impression upon a
+traveller, who journeys for the sake of "sensations," may be
+strengthened by the mysterious annihilation of all standards for the
+measurement of space, yet the superior intelligibility of the winter
+scenery of Italy is more profitable to those who see with a view to
+analyze.
+
+[294] Copse, or coppice, from the French _couper_, to cut, signifies
+properly a wood the trees of which are cut at certain periods of
+immature growth, and allowed to shoot up again from the roots; but it
+has come to signify, very commonly, a young wood, grove, or thicket,
+without reference to its origin, or to its character of a forest crop.
+
+[295] It has been recently stated, upon the evidence of the Government
+foresters of Greece, and of the queen's gardener, that a large wood has
+been discovered in Arcadia, consisting of a fir which has the property
+of sending up both vertical and lateral shoots from the stump of felled
+trees and forming a new crown. It was at first supposed that this forest
+grew only on the "mountains," of which the hero of About's most amusing
+story, _Le Roi des Montagnes_, was "king;" but it is now said that small
+stumps, with the shoots attached, have been sent to Germany, and
+recognized by able botanists as true natural products.
+
+[296] Natural forests are rarely, if ever, composed of trees of a single
+species, and experience has shown that oaks and other broad-leaved
+trees, planted as artificial woods, require to be mixed, or associated
+with others of different habits.
+
+In the forest of Fontainebleau, "oaks, mingled with beeches in due
+proportion," says Clave, "may arrive at the age of five or six hundred
+years in full vigor, and attain dimensions which I have never seen
+surpassed; when, however, they are wholly unmixed with other trees, they
+begin to decay and die at the top, at the age of forty or fifty years,
+like men, old before their time, weary of the world, and longing only to
+quit it. This has been observed in most of the oak plantations of which
+I have spoken, and they have not been able to attain to full growth.
+When the vegetation was perceived to languish, they were cut, in the
+hope that this operation would restore their vigor, and that the new
+shoots would succeed better than the original trees; and, in fact, they
+seemed to be recovering for the first few years. But the shoots were
+soon attacked by the same decay, and the operation had to be renewed at
+shorter and shorter intervals, until at last it was found necessary to
+treat as coppices plantations originally designed for the full-growth
+system. Nor was this all: the soil, periodically bared by these
+cuttings, became impoverished, and less and less suited to the growth of
+the oak. * * * It was then proposed to introduce the pine and plant with
+it the vacancies and glades. * * * By this means, the forest was saved
+from the ruin which threatened it, and now more than 10,000 acres of
+pines, from fifteen to thirty years old, are disseminated at various
+points, sometimes intermixed with broad-leaved trees, sometimes forming
+groves by themselves."--_Revue des Deux Mondes_, Mai, 1863, pp. 153,
+154.
+
+The forests of Denmark, which, in modern times, have been succeeded by
+the beech--a species more inclined to be exclusive than any other
+broad-leaved tree--were composed of birches, oaks, firs, aspens,
+willows, hazel, and maple, the first three being the leading species. At
+present, the beech greatly predominates.--VAUPELL, _Boegens Indvandring_,
+pp. 19, 20.
+
+[297] _Etudes Forestieres_, p. 89.
+
+[298] The grounds which it is most important to clothe with wood as a
+conservative influence, and which, also, can best be spared from
+agricultural use, are steep hillsides. But the performance of all the
+offices of the forester to the tree--seeding, planting, thinning, and
+finally felling and removing for consumption--is more laborious upon a
+rapid declivity than on a level soil, and at the same time it is
+difficult to apply irrigation or manures to trees so situated.
+Experience has shown that there is great advantage in terracing the face
+of a hill before planting it, both as preventing the wash of the earth
+by checking the flow of water down its slope, and as presenting a
+surface favorable for irrigation, as well as for manuring and
+cultivating the tree. But even without so expensive a process, very
+important results have been obtained by simply ditching declivities. "In
+order to hasten the growth of wood on the flanks of a mountain, Mr.
+Eugene Chevandier divided the slope into zones forty or fifty feet wide,
+by horizontal ditches closed at both ends, and thereby obtained, from
+firs of different ages, shoots double the dimensions of those which grew
+on a dry soil of the same character, where the water was allowed to run
+off without obstruction."--DUMONT, _Des Travaux Publics, etc._, pp.
+94-96.
+
+The ditches were about two feet and a half deep, and three feet and a
+half wide, and they cost about forty francs the hectare, or three
+dollars the acre. This extraordinary growth was produced wholly by the
+retention of the rain water in the ditches, whence it filtered through
+the whole soil and supplied moisture to the roots of the trees. It may
+be doubted whether in a climate cold enough to freeze the entire
+contents of the ditches in winter, it would not be expedient to draw off
+the water in the autumn, as the presence of so large a quantity of ice
+in the soil might prove injurious to trees too young and small to
+shelter the ground effectually against frost.
+
+Chevandier computes that, if the annual growth of the pine in the marshy
+soil of the Vosges be represented by one, it will equal two in dry
+ground, four or five on slopes so ditched or graded as to retain the
+water flowing upon them from roads or steep declivities, and six where
+the earth is kept constantly moist by infiltration from running
+brooks.--_Comptes Rendus a l'Academie des Sciences_--t. xix, Juillet,
+Dec., 1844, p. 167.
+
+The effect of accidental irrigation is well shown in the growth of the
+trees planted along the canals of irrigation which traverse the fields
+in many parts of Italy. They flourish most luxuriantly, in spite of
+continual lopping, and yield a very important contribution to the stock
+of fuel for domestic use; while trees, situated so far from canals as to
+be out of the reach of infiltration from them, are of much slower
+growth, under circumstances otherwise equally favorable.
+
+In other experiments of Chevandier, under better conditions, the yield
+of wood was increased, by judicious irrigation, in the ratio of seven to
+one, the profits in that of twelve to one. At the Exposition of 1855,
+Chambrelent exhibited young trees, which, in four years from the seed,
+had grown to the height of sixteen and twenty feet, and the diameter of
+ten and twelve inches. Chevandier experimented with various manures, and
+found that some of them might be profitably applied to young, but not to
+old trees, the quantity required in the latter case being too great.
+Wood ashes and the refuse of soda factories are particularly
+recommended. I have seen an extraordinary growth produced in fir trees
+by the application of soapsuds.
+
+[299] Although the economy of the forest has received little attention
+in the United States, no lover of American nature can have failed to
+observe a marked difference between a native wood from which cattle are
+excluded and one where they are permitted to browse. A few seasons
+suffice for the total extirpation of the "underbrush," including the
+young trees on which alone the reproduction of the forest depends, and
+all the branches of those of larger growth which hang within reach of
+the cattle are stripped of their buds and leaves, and soon wither and
+fall off. These effects are observable at a great distance, and a wood
+pasture is recognized, almost as far as it can be seen, by the
+regularity with which its lower foliage terminates at what Ruskin
+somewhere calls the "cattle line." This always runs parallel to the
+surface of the ground, and is determined by the height to which domestic
+quadrupeds can reach to feed upon the leaves. In describing a visit to
+the grand-ducal farm of San Rossore near Pisa, where a large herd of
+camels is kept, Chateauvieux says: "In passing through a wood of
+evergreen oaks, I observed that all the twigs and foliage of the trees
+were clipped up to the height of about twelve feet above the ground,
+without leaving a single spray below that level. I was informed that the
+browsing of the camels had trimmed the trees as high as they could
+reach."--LULLIN DE CHATEAUVIEUX, _Lettres sur l'Italie_, p. 113.
+
+The removal of the shelter afforded by the brushwood and the pendulous
+branches of trees permits drying and chilling winds to parch and cool
+the ground, and of course injuriously affects the growth of the wood.
+But this is not all. The tread of quadrupeds exposes and bruises the
+roots of the trees, which often die from this cause, as any one may
+observe by following the paths made by cattle through woodlands.
+
+[300] I have remarked elsewhere that most insects which deposit and
+hatch their eggs in the wood of the natural forest confine themselves to
+dead trees. Not only is this the fact, but it is also true that many of
+the borers attack only freshly cut timber. Their season of labor is a
+short one, and unless the tree is cut during this period, it is safe
+from them. In summer you may hear them plying their augers in the wood
+of a young pine with soft green bark, as you sit upon its trunk, within
+a week after it has been felled, but the windfalls of the winter lie
+uninjured by the worm and even undecayed for centuries. In the pine
+woods of New England, after the regular lumberman has removed the
+standing trees, these old trunks are hauled out from the mosses and
+leaves which half cover them, and often furnish excellent timber. The
+slow decay of such timber in the woods, it may be remarked, furnishes
+another proof of the uniformity of temperature and humidity in the
+forest, for the trunk of a tree lying on grass or plough land, and of
+course exposed to all the alternations of climate, hardly resists
+complete decomposition for a generation. The forests of Europe exhibit
+similar facts. Wessely, in a description of the primitive wood of
+Neuwald in Lower Austria, says that the windfalls required from 150 to
+200 years for entire decay.-_-Die Oesterreichischen Alpenlaender und ihre
+Forste_, p. 312.
+
+[301] VAUPELL, _Boegens Indvandring i de Danske Skove_, pp. 29, 46.
+Vaupell further observes, on the page last quoted: "The removal of
+leaves is injurious to the forest, not only because it retards the
+growth of trees, but still more because it disqualifies the soil for the
+production of particular species. When the beech languishes, and the
+development of its branches is less vigorous and its crown less
+spreading, it becomes unable to resist the encroachments of the fir.
+This latter tree thrives in an inferior soil, and being no longer
+stifled by the thick foliage of the beech, it spreads gradually through
+the wood, while the beech retreats before it and finally perishes."
+
+The study of the natural order of succession in forest trees is of the
+utmost importance in sylviculture, because it guides us in the selection
+of the species to be employed in planting a new or restoring a decayed
+forest. When ground is laid bare both of trees and of vegetable mould,
+and left to the action of unaided and unobstructed nature, she first
+propagates trees which germinate and grow only under the influence of a
+full supply of light and air, and then, in succession, other species,
+according to their ability to bear the shade and their demand for more
+abundant nutriment. In Northern Europe, the larch, the white birch, the
+aspen, first appear; then follow the maple, the alder, the ash, the fir;
+then the oak and the linden; and then the beech. The trees called by
+these respective names in the United States are not specifically the
+same as their European namesakes, nor are they always even the
+equivalents of these latter, and therefore the order of succession in
+America would not be precisely as indicated by the foregoing list, but
+it nevertheless very nearly corresponds to it.
+
+It is thought important to encourage the growth of the beech in Denmark
+and Northern Germany, because it upon the whole yields better returns
+than other trees, and particularly because it appears not to exhaust,
+but on the contrary to enrich the soil; for by shedding its leaves it
+returns to it most of the nutriment it has drawn from it, and at the
+same time furnishes a solvent which aids materially in the decomposition
+of its mineral constituents.
+
+When the forest is left to itself, the order of succession is constant,
+and its occasional inversion is always explicable by some human
+interference. It is curious that the trees which require most light are
+content with the poorest soils, and _vice versa_. The trees which first
+appear are also those which propagate themselves farthest to the north.
+The birch, the larch, and the fir bear a severer climate than the oak,
+the oak than the beech. "These parallelisms," says Vaupell, "are very
+interesting, because they are entirely independent of each other," and
+each prescribes the same order of succession.--_Boegens Indvandring_, p.
+42.
+
+[302] When vigorous young locusts, of two or three inches in diameter,
+are polled, they throw out a great number of very thick-leaved shoots,
+which arrange themselves in a globular head, so unlike the natural crown
+of the acacia, that persons familiar only with the untrained tree often
+take them for a different species.
+
+[303] The two ideas expressed in the text are not exactly equivalent,
+because, though the consumption of animal food diminishes the amount of
+vegetable aliment required for human use, yet the animals themselves
+consume a great quantity of grain and roots grown on ground ploughed and
+cultivated as regularly and as laboriously as any other.
+
+The 170,000,000 bushels of oats raised in the United States in 1860, and
+fed to the 6,000,000 horses, the potatoes, the turnips, and the maize
+employed in fattening the oxen, the sheep, and the swine slaughtered the
+same year, occupied an extent of ground which, cultivated by hand labor
+and with Chinese industry and skill, would probably have produced a
+quantity of vegetable food equal in alimentary power to the flesh of the
+quadrupeds killed for domestic use. Hence, so far as the naked question
+of _amount_ of aliment is concerned, the meadows and the pastures might
+as well have remained in the forest condition.
+
+[304] According to Clave (_Etudes_, p. 159), the net revenue from the
+forests of the state in France, making no allowance for interest on the
+capital represented by the forest, is two dollars per acre. In Saxony it
+is about the same, though the cost of administration is twice as much as
+in France; in Wuertemberg it is about a dollar an acre; and in Prussia,
+where half the income is consumed in the expenses of administration, it
+sinks to less than half a dollar. This low rate in Prussia is partly
+explained by the fact that a considerable proportion of the annual
+product of wood is either conceded to persons claiming prescriptive
+rights, or sold, at a very small price, to the poor. Taking into account
+the capital invested in forest land, and adding interest upon it,
+Pressler calculates that a pine wood, managed with a view to felling it
+when eighty years old, would yield only one eighth of one per cent.
+annual profit; a fir wood, at one hundred years, one sixth of one per
+cent.; a beech wood, at one hundred and twenty years, one fourth of one
+per cent. The same author (p. 335) gives the net income of the New
+forest in England, over and above expenses, interest not computed, at
+twenty-five cents per acre only. In America, where no expense is
+bestowed upon the woods, the annual growth would generally be estimated
+much higher.
+
+[305] It is rare that a middle-aged American dies in the house where he
+was born, or an old man even in that which he has built; and this is
+scarcely less true of the rural districts, where every man owns his
+habitation, than of the city, where the majority live in hired houses.
+This life of incessant flitting is unfavorable for the execution of
+permanent improvements of every sort, and especially of those which,
+like the forest, are slow in repaying any part of the capital expended
+in them. It requires a very generous spirit in a landholder to plant a
+wood on a farm he expects to sell, or which he knows will pass out of
+the hands of his descendants at his death. But the very fact of having
+begun a plantation would attach the proprietor more strongly to the soil
+for which he had made such a sacrifice; and the paternal acres would
+have a greater value in the eyes of a succeeding generation, if thus
+improved and beautified by the labors of those from whom they were
+inherited. Landed property, therefore, the transfer of which is happily
+free from every legal impediment or restriction in the United States,
+would find, in the feelings thus prompted, a moral check against a too
+frequent change of owners, and would tend to remain long enough in one
+proprietor or one family to admit of gradual improvements which would
+increase its value both to the possessor and to the state.
+
+[306] It has been often asserted by eminent writers that a part of the
+fens in Lincolnshire was reclaimed by sea dikes under the government of
+the Romans. I have found no ancient authority in support of this
+allegation, nor can I refer to any passage in Roman literature in which
+sea dikes are expressly mentioned otherwise than as walls or piers,
+except that in Pliny (_Hist. Nat._ xxxvi, 24), where it is said that the
+Tyrrhenian sea was excluded from the Lucrine lake by dikes.
+
+[307] A friend has recently suggested to me an interesting illustration
+of the applicability of military instrumentalities to pacific art. The
+sale of gunpowder in the United States, he informs me, is smaller since
+the commencement of the present rebellion than before, because the war
+has caused the suspension of many public and private improvements, in
+the execution of which great quantities of powder were used for
+blasting.
+
+It is alleged that the same observation was made in France during the
+Crimean war, and that, in general, not ten per cent. of the powder
+manufactured on either side of the Atlantic is employed for military
+purposes.
+
+It is a fact not creditable to the moral sense of modern civilization,
+that very many of the most important improvements in machinery and the
+working of metals have originated in the necessities of war, and that
+man's highest ingenuity has been shown, and many of his most remarkable
+triumphs over natural forces achieved, in the contrivance of engines for
+the destruction of his fellow man. The military material employed by the
+first Napoleon has become, in less than two generations, nearly as
+obsolete as the sling and stone of the shepherd, and attack and defence
+now begin at distances to which, half a century ago, military
+reconnoissances hardly extended. Upon a partial view of the subject, the
+human race seems destined to become its own executioner--on the one
+hand, exhausting the capacity of the earth to furnish sustenance to her
+taskmaster; on the other, compensating diminished production by
+inventing more efficient methods of exterminating the consumer.
+
+But war develops great civil virtues, and brings into action a degree
+and kind of physical energy which seldom fails to awaken a new
+intellectual life in a people that achieves great moral and political
+results through great heroism and endurance and perseverance. Domestic
+corruption has destroyed more nations than foreign invasion, and a
+people is rarely conquered till it has deserved subjugation.
+
+[308] STARING, _Voormaals en Thans_, p. 150.
+
+[309] Idem, p. 163. Much the largest proportion of the lands so
+reclaimed, though for the most part lying above low-water tidemark, are
+at a lower level than the Lincolnshire fens, and more subject to
+inundation from the irruptions of the sea.
+
+[310] _Die Inseln und Marschen der Herzogthuemer Schleswig und Holstein_,
+iii, p. 151.
+
+[311] The purely agricultural island of Pelworm, off the coast of
+Schleswig, containing about 10,000 acres, annually expends for the
+maintenance of its dikes not less than L6,000 sterling, or nearly
+$30,000.--J. G. KOHL, _Inseln und Marschen Schleswig's und Holstein's_,
+ii, p. 394.
+
+The original cost of the dikes of Pelworm is not stated.
+
+"The greatest part of the province of Zeeland is protected by dikes
+measuring 250 miles in length, the maintenance of which costs, in
+ordinary years, more than a million guilders [above $400,000]. * * * The
+annual expenditure for dikes and hydraulic works in Holland is from five
+to seven million guilders" [$2,000,000 to $2,800,000].--WILD, _Die
+Niederlande_, i, p. 62.
+
+One is not sorry to learn that the Spanish tyranny in the Netherlands
+had some compensations. The great chain of ring dikes which surrounds a
+large part of Zeeland is due to the energy of Caspar de Robles, the
+Spanish governor of that province, who in 1570 ordered the construction
+of these works at the public expense, as a substitute for the private
+embankments which had previously partially served the same
+purpose.--WILD, _Die Niederlande_, i, p. 62.
+
+[312] STARING, _Voormaals en Thans_, p. 163.
+
+[313] _Voormaals en Thans_, pp. 150, 151.
+
+[314] STARING, _Voormaals en Thans_, p. 152. Kohl states that the
+peninsula of Diksand on the coast of Holstein consisted, at the close of
+the last century, of several islands measuring together less than five
+thousand acres. In 1837 they had been connected with the mainland, and
+had nearly doubled in area.--_Inseln u. Marschen Schlesw. Holst._, iii,
+p. 262.
+
+[315] The most instructive and entertaining of tourists, J. G. Kohl--so
+aptly characterized by Davies as the "Herodotus of modern
+Europe"--furnishes a great amount of interesting information on the
+dikes of the Low German seacoast, in his _Inseln und Marschen der
+Herzogthuemer Schleswig und Holstein_. I am acquainted with no popular
+work on this subject which the reader can consult with greater profit.
+See also STARING, _Voormaals en Thans_, and _De Bodem van Nederland_, on
+the dikes of the Netherlands.
+
+[316] The inclination varies from one foot rise in four of base to one
+foot in fourteen.--KOHL, iii, p. 210.
+
+[317] The dikes are sometimes founded upon piles, and sometimes
+protected by one or more rows of piles driven deeply down into the bed
+of the sea in front of them. "Triple rows of piles of Scandinavian
+pine," says Wild, "have been driven down along the coast of Friesland,
+where there are no dunes, for a distance of one hundred and fifty miles.
+The piles are bound together by strong cross timbers and iron clamps,
+and the interstices filled with stones. The ground adjacent to the
+piling is secured with fascines, and at exposed points heavy blocks of
+stone are heaped up as an additional protection. The earth dike is built
+behind the mighty bulwark of this breakwater, and its foot also is
+fortified with stones." * * * "The great Helder dike is about five miles
+long and forty feet wide at the top, along which runs a good road. It
+slopes down two hundred feet into the sea, at an angle of forty degrees.
+The highest waves do not reach the summit, the lowest always cover its
+base. At certain distances, immense buttresses, of a height and width
+proportioned to those of the dike, and even more strongly built, run
+several hundred feet out into the rolling sea. This gigantic artificial
+coast is entirely composed of Norwegian granite."--WILD, _Die
+Niederlande_, i, pp. 61, 62.
+
+[318] The shaking of the ground, even when loaded with large buildings,
+by the passage of heavy carriages or artillery, or by the march of a
+body of cavalry or even infantry, shows that such causes may produce
+important mechanical effects on the condition of the soil. The bogs in
+the Netherlands, as in most other countries, contain large numbers of
+fallen trees, buried to a certain depth by earth and vegetable mould.
+When the bogs are dry enough to serve as pastures, it is observed that
+trunks of these ancient trees rise of themselves to the surface. Staring
+ascribes this singular phenomenon to the agitation of the ground by the
+tread of cattle. "When roadbeds," observes he, "are constructed of
+gravel and pebbles of different sizes, and these latter are placed at
+the bottom without being broken and rolled hard together, they are soon
+brought to the top by the effect of travel on the road. Lying loosely,
+they undergo some motion from the passage of every wagon wheel and the
+tread of every horse that passes over them. This motion is an
+oscillation or partial rolling, and as one side of a pebble is raised, a
+little fine sand or earth is forced under it, and the frequent
+repetition of this process by cattle or carriages moving in opposite
+directions brings it at last to the surface. We may suppose that a
+similar effect is produced on the stems of trees in the bogs by the
+tread of animals."--_De Bodem van Nederland_, i, pp. 75, 76.
+
+It is observed in the Northern United States, that when soils containing
+pebbles are cleared and cultivated, and the stones removed from the
+surface, new pebbles, and even bowlders of many pounds weight, continue
+to show themselves above the ground, every spring, for a long series of
+years. In clayey soils the fence posts are thrown up in a similar way,
+and it is not uncommon to see the lower rail of a fence thus gradually
+raised a foot or even two feet above the ground. This rising of stones
+and fences is popularly ascribed to the action of the severe frosts of
+that climate. The expansion of the ground, in freezing, it is said,
+raises its surface, and, with the surface, objects lying near or
+connected with it. When the soil thaws in the spring, it settles back
+again to its former level, while the pebbles and posts are prevented
+from sinking as low as before by loose earth which has fallen under
+them. The fact that the elevation spoken of is observed only in the
+spring, gives countenance to this theory, which is perhaps applicable
+also to the cases stated by Staring, and it is probable that the two
+causes above assigned concur in producing the effect.
+
+The question of the subsidence of the Netherlandish coast has been much
+discussed. Not to mention earlier geologists, Venema, in several essays,
+and particularly in _Het Dalen van de Noordelijke Kuststreken van ons
+Land_, 1854, adduces many facts and arguments to prove a slow sinking of
+the northern provinces of Holland. Laveleye (_Affaissement du sol et
+envasement des fleuves survenus dans les temps historiques_, 1859), upon
+a still fuller investigation, arrives at the same conclusion. The
+eminent geologist Staring, however, who briefly refers to the subject in
+_De Bodem van Nederland_, i, p. 356 _et seqq._, does not consider the
+evidence sufficient to prove anything more than the sinking of the
+surface of the polders from drying and consolidation.
+
+[319] The elevation of the lands enclosed by dikes--or _polders_, as
+they are called in Holland--above low water mark, depends upon the
+height of the tides, or, in other words, upon, the difference between
+ebb and flood. The tide cannot deposit earth higher than it flows, and
+after the ground is once enclosed, the decay of the vegetables grown
+upon it and the addition of manures do not compensate the depression
+occasioned by drying and consolidation. On the coast of Zeeland and the
+islands of South Holland, the tides, and of course the surface of the
+lands deposited by them, are so high that the polders can be drained by
+ditching and sluices, but at other points, as in the enclosed grounds of
+North Holland on the Zuiderzee, where the tide rises but three feet or
+even less, pumping is necessary from the beginning.--STARING, _Voormaals
+en Thans_, p. 152.
+
+[320] The principal engine--called the Leeghwater, from the name of an
+engineer who had proposed the draining of the lake in 1641--was of 500
+horse power, and drove eleven pumps making six strokes per minute. Each
+pump raised six cubic metres, or nearly eight cubic yards of water to
+the stroke, amounting in all to 23,760 cubic metres, or above 31,000
+cubic yards, the hour.--WILD, _Die Niederlande_, i, p. 87.
+
+[321] In England and New England, where the marshes have been already
+drained or are of comparatively small extent, the existence of large
+floating islands seems incredible, and has sometimes been treated as a
+fable, but no geographical fact is better established. Kohl (_Inseln und
+Marschen Schleswig-Holsteins_, iii, p. 309) reminds us that Pliny
+mentions among the wonders of Germany the floating islands, covered with
+trees, which met the Roman fleets at the mouths of the Elbe and the
+Weser. Our author speaks also of having visited, in the territory of
+Bremen, floating moors, bearing not only houses but whole villages. At
+low stages of the water these moors rest upon a bed of sand, but are
+raised from six to ten feet by the high water of spring, and remain
+afloat until, in the course of the summer, the water beneath is
+exhausted by evaporation and drainage, when they sink down upon the sand
+again. See _Appendix_, No. 40.
+
+Staring explains, in an interesting way, the whole growth, formation,
+and functions of floating fens or bogs, in his very valuable work, _De
+Bodem van_ _Nederland_, i, pp. 36-43. The substance of his account is as
+follows: The first condition for the growth of the plants which compose
+the substance of turf and the surface of the fens, is stillness of the
+water. Hence they are not found in running streams, nor in pools so
+large as to be subject to frequent agitation by the wind. For example,
+not a single plant grew in the open part of the Lake of Haarlem, and
+fens cease to form in all pools as soon as, by the cutting of the turf
+for fuel or other purposes, their area is sufficiently enlarged to be
+much acted on by wind. When still water above a yard deep is left
+undisturbed, aquatic plants of various genera, such us Nuphar, Nymphaea,
+Limnanthemum, Stratiotes, Polygonum, and Potamogeton, fill the bottom
+with roots and cover the surface with leaves. Many of the plants die
+every year, and prepare at the bottom a soil fit for the growth of a
+higher order of vegetation, Phragmites, Acorus, Sparganium, Rumex,
+Lythrum, Pedicularis, Spiraea, Polystichum, Comarum, Caltha, &c., &c. In
+the course of twenty or thirty years the muddy bottom is filled with
+roots of aquatic and marsh plants, which are lighter than water, and if
+the depth is great enough to give room for detaching this vegetable
+network, a couple of yards for example, it rises to the surface, bearing
+with it, of course, the soil formed above it by decay of stems and
+leaves. New genera now appear upon the mass, such as Carex, Menyanthes,
+and others, and soon thickly cover it. The turf has now acquired a
+thickness of from two to four feet, and is called in Groningen _lad_; in
+Friesland, _til_, _tilland_, or _drijftil_; in Overijssel, _krag_; and
+in Holland, _rietzod_. It floats about as driven by the wind, gradually
+increasing in thickness by the decay of its annual crops of vegetation,
+and in about half a century reaches the bottom and becomes fixed. If it
+has not been invaded in the mean time by men or cattle, trees and
+arborescent plants, Alnus, Salix, Myrica, &c. appear, and these
+contribute to hasten the attachment of the turf to the bottom, both by
+their weight and by sending their roots quite through into the ground.
+
+This is the regular method employed by nature for the gradual filling up
+of shallow lakes and pools, and converting them first into morass and
+then into dry land. Whenever therefore man removes the peat or turf, he
+exerts an injurious geographical agency, and, as I have already said,
+there is no doubt that the immense extension of the inland seas of
+Holland in modern times is owing to this and other human imprudences.
+"Hundreds of hectares of floating pastures," says our author, "which
+have nothing in their appearance to distinguish them from grass lands
+resting on solid bog, are found in Overijssel, in North Holland and near
+Utrecht. In short, they occur in all deep bogs, and wherever deep water
+is left long undisturbed."
+
+In one case, a floating island, which had attached itself to the shore,
+continued to float about for a long time after it was torn off by a
+flood, and was solid enough to keep a pond of fresh water upon it sweet,
+though the water in which it was swimming had become brackish from the
+irruption of the sea. After the hay is cut, cattle are pastured upon
+those islands, and they sometimes have large trees growing upon them.
+
+When the turf or peat has been cut, leaving water less than a yard deep,
+Equisetum limosum grows at once, and is followed by the second class of
+marsh plants mentioned above. Their roots do not become detached from
+the bottom in such shallow water, but form ordinary turf or peat. These
+processes are so rapid that a thickness of from three to six feet of
+turf is formed in half a century, and many men have lived to mow grass
+where they had fished in their boyhood, and to cut turf twice in the
+same spot.
+
+Captain Gilliss says that before Lake Taguataga in Chili was drained,
+there were in it islands composed of dead plants matted together to a
+thickness of from four to six feet, and with trees of medium size
+growing upon them. These islands floated before the wind "with their
+trees and browsing cattle."--_United States Naval Astronomical
+Expedition to the Southern Hemisphere_, i, pp. 16, 17.
+
+[322] A considerable work of this character is mentioned by Captain
+Gilliss as having been executed in Chili, a country to which we should
+have hardly looked for an improvement of such a nature. The Lake
+Taguataga was partially drained by cutting through a narrow ridge of
+land, not at the natural outlet, but upon one side of the lake, and
+eight thousand acres of land covered by it were gained for
+cultivation.--_U. S. Naval Astronomical Expedition to the Southern
+Hemisphere_, i, pp. 16, 17.
+
+[323] _Economie Rurale de la France_, p. 289.
+
+[324] In a note on a former page of this volume I noticed an observation
+of Jacini, to the effect that the great Italian lakes discharge
+themselves partly by infiltration beneath the hills which bound them.
+The amount of such infiltration must depend much upon the hydrostatic
+pressure on the walls of the lake basins, and, of course, the lowering
+of the surface of these lakes, by diminishing that pressure, would
+diminish also the infiltration. It is now proposed to lower the level of
+the Lake of Como some feet by deepening its outlet. It is possible that
+the effect of this may manifest itself in a diminution of the water in
+springs and _fontanili_ or artesian wells in Lombardy. See _Appendix_,
+No. 43.
+
+[325] Simonde, speaking of the Tuscan canals, observes: "But inundations
+are not the only damage caused by the waters to the plains of Tuscany.
+Raised, as the canals are, above the soil, the water percolates through
+their banks, penetrates every obstruction, and, in spite of all the
+efforts of industry, sterilizes and turns to morasses fields which
+nature and the richness of the soil seemed to have designed for the most
+abundant harvests. In ground thus pervaded with moisture, or rendered
+_cold_, as the Tuscans express it, by the filtration of the canal water,
+the vines and the mulberries, after having for a few years yielded fruit
+of a saltish taste, rot and perish. The wheat decays in the ground, or
+dies as soon as it sprouts. Winter crops are given up, and summer
+cultivation tried for a time; but the increasing humidity, and the
+saline matter communicated to the earth--which affects the taste of all
+its products, even to the grasses, which the cattle refuse to touch--at
+last compel the husbandman to abandon his fields, and leave uncultivated
+a soil that no longer repays his labor."--_Tableau de l'Agriculture
+Toscane._ pp. 11, 12.
+
+[326] _Physikalische Geographie_, p. 288. Draining by driving down
+stakes, mentioned in a note in a chapter on the woods, _ante_, is a
+process of the same nature.
+
+[327] "The simplest backwoodsman knows by experience that all
+cultivation is impossible in the neighborhood of bogs and marshes. Why
+is a crop near the borders of a marsh cut off by frost, while a field
+upon a hillock, a few stone's throws from it, is spared?"--LARS LEVI
+LAESTADIUS, _Om Uppodlingar i Lappmarken_, pp. 69, 74.
+
+[328] Babinet condemns even the general draining of marshes. "Draining,"
+says he, "has been much in fashion for some years. It has been a special
+object to dry and fertilize marshy grounds. My opinion has always been
+that excessive dryness is thus produced, and that other soils in the
+neighborhood are sterilized in proportion."
+
+[329] I ought perhaps to except the Mexicans and the Peruvians, whose
+arts and institutions are not yet shown to be historically connected
+with those of any more ancient people. The lamentable destruction of so
+many memorials of these tribes, by the ignorance and bigotry of the
+so-called Christian barbarians who conquered them, has left us much in
+the dark as to many points of their civilization; but they seem to have
+reached that stage where continued progress in knowledge and in power
+over nature is secure, and a few more centuries of independence might
+have brought them to originate for themselves most of the great
+inventions which the last four centuries have bestowed upon man.
+
+[330] The necessity of irrigation in the great alluvial plain of
+Northern Italy is partly explained by the fact that the superficial
+stratum of fine earth and vegetable mould is very extensively underlaid
+by beds of pebbles and gravel brought down by mountain torrents at a
+remote epoch. The water of the surface soil drains rapidly down into
+these loose beds, and passes off by subterranean channels to some
+unknown point of discharge; but this circumstance alone is not a
+sufficient solution. Is it not possible that the habits of vegetables,
+grown in countries where irrigation has been immemorially employed, have
+been so changed that they require water under conditions of soil and
+climate where their congeners, which have not been thus indulgently
+treated, do not?
+
+There are some atmospheric phenomena in Northern Italy, which an
+American finds it hard to reconcile with what he has observed in the
+United States. To an American eye, for instance, the sky of Piedmont,
+Lombardy, and the northern coast of the Mediterranean, is always whitish
+and curdled, and it never has the intensity and fathomless depth of the
+blue of his native heavens. And yet the heat of the sun's rays, as
+measured by sensation, and, at the same time, the evaporation, are
+greater than they would be with the thermometer at the same point in
+America. I have frequently felt in Italy, with the mercury below 60 deg.
+Fahrenheit, and with a mottled and almost opaque sky, a heat of solar
+irradiation which I can compare to nothing but the scorching sensation
+experienced in America at a temperature twenty degrees higher, during
+the intervals between showers, or before a rain, when the clear blue of
+the sky seems infinite in depth and transparency. Such circumstances may
+create a necessity for irrigation where it would otherwise be
+superfluous, if not absolutely injurious.
+
+In speaking of the superior apparent clearness of the _sky_ in America,
+I confine myself to the concave vault of the heavens, and do not mean to
+assert that terrestrial objects are generally visible at greater
+distances in the United States than in Italy. Indeed I am rather
+disposed to maintain the contrary; for though I know that the lower
+strata of the atmosphere in Europe never equal in transparency the air
+near the earth in New Mexico, Peru, and Chili, yet I think the accidents
+of the coast line of the Riviera, as, for example, between Nice and La
+Spezia, and those of the incomparable Alpine panorama seen from Turin,
+are distinguishable at greater distances than they would be in the
+United States.
+
+[331] In Egypt, evaporation and absorption by the earth are so rapid,
+that all annual crops require irrigation during the whole period of
+their growth. As fast as the water retires by the subsidence of the
+annual inundation, the seed is sown upon the still moist uncovered soil,
+and irrigation begins at once. Upon the Nile, you hear the creaking of
+the water wheels, and sometimes the movement of steam pumps, through the
+whole night, while the poorer cultivators unceasingly ply the simple
+_shadoof_, or bucket-and-sweep, laboriously raising the water from
+trough to trough by as many as six or seven stages when the river is
+low. The bucket is of flexible leather, with a stiff rim, and is emptied
+into the trough, not by inverting it like a wooden bucket, but by
+putting the hand beneath and pushing the bottom up till the water all
+runs out over the brim, or, in other words, by turning the vessel inside
+out.
+
+The quantity of water thus withdrawn from the Nile is enormous. Most of
+this is evaporated directly from the surface or the superficial strata,
+but some moisture percolates down and oozes through the banks into the
+river again, while a larger quantity sinks till it joins the slow
+current of infiltration by which the Nile water pervades the earth of
+the valley to the distance, at some points, of not less than fifty
+miles.
+
+[332] "Forests," "woods," and "groves," are very frequently mentioned in
+the Old Testament as existing at particular places, and they are often
+referred to by way of illustration, as familiar objects. "Wood" is twice
+spoken of as a material in the New Testament, but otherwise--at least
+according to Cruden--not one of the above words occurs in that volume.
+
+This interesting fact, were other evidence wanting, would go far to
+prove that a great change had taken place in this respect between the
+periods when the Old Testament and the New were respectively composed;
+for the scriptural writers, and the speakers introduced into their
+narratives, are remarkable for their frequent allusions to the natural
+objects and the social and industrial habits which characterized their
+ages and their country. See _Appendix_, No. 44.
+
+Solomon anticipated Chevandier in the irrigation of forest trees: "I
+made me pools of water, to water therewith the wood that bringeth forth
+trees."--_Ecclesiastes_ ii, 6.
+
+[333] One of these, upon Mount Hor, two stories in height, is still in
+such preservation that I found not less than ten feet of water in it in
+the month of June, 1851.
+
+The brook Ain Musa, which runs through the city of Petra and finally
+disappears in the sands of Wadi el Araba, is a considerable river in
+winter, and the inhabitants of that town were obliged to excavate a
+tunnel through the rock near the right bank, just above the upper
+entrance of the Sik, to discharge a part of its swollen current. The
+sagacity of Dr. Robinson detected the necessity of this measure, though
+the tunnel, the mouth of which was hidden by brushwood, was not
+discovered till some time after his visit. I even noticed unequivocal
+remains of a sluice by which the water was diverted to the tunnel near
+the arch that crosses the Sik. Immense labor was also expended in
+widening the natural channel at several points below the town, to
+prevent the damming up and setting back of the water--a fact I believe
+not hitherto noticed by travellers.
+
+The Fellahheen above Petra still employ the waters of Ain Musa for
+irrigation, and in summer the superficial current is wholly diverted
+from its natural channel for that purpose. At this season, the bed of
+the brook, which is composed of pebbles, gravel, and sand, is dry in the
+Sik and through the town; but the infiltration is such that water is
+generally found by digging to a small depth in the channel. Observing
+these facts in a visit to Petra in the summer, I was curious to know
+whether the subterranean waters escaped again to daylight, and I
+followed the ravine below the town for a long distance. Not very far
+from the upper entrance of the ravine, arborescent vegetation appeared
+upon its bottom, and as soon as the ground was well shaded, a thread of
+water burst out. This was joined by others a little lower down, and, at
+the distance of a mile from the town, a strong current was formed and
+ran down toward Wadi el Araba.
+
+[334] The authorities differ as to the extent of the cultivable and the
+cultivated soil of Egypt. Lippincott's, or rather Thomas and Baldwin's,
+_Gazetteer_--a work of careful research--estimates "the whole area
+comprised in the valley [below the first cataract] and delta," at 11,000
+square miles. Smith's _Dictionary of the Bible_, article "Egypt," says:
+"Egypt has a superficies of about 9,582 square geographical miles of
+soil, which the Nile either does or can water and fertilize. This
+computation includes the river and lakes as well as sundry tracts which
+can be inundated, and the whole space either cultivated or fit for
+cultivation is no more than about 5,626 square miles." By geographical
+mile is here meant, I suppose, the nautical mile of sixty to an
+equatorial degree, or about 2,025 yards. The whole area, then, by this
+estimate, is 12,682 square statute or English miles, that of the space
+"cultivated or fit for cultivation," 7,447. Smith's _Dictionary of Greek
+and Roman Geography_, article "AEgyptus," gives 2,255 square miles as the
+area of the valley between Syene and the bifurcation of the Nile,
+exclusive of the Fayoom, which is estimated at 340. The area of the
+Delta is stated at 1,976 square miles between the main branches of the
+river, and, including the irrigated lands east and west of those
+branches, at 4,500 square miles. This latter work does not inform us
+whether these are statute or nautical miles, but nautical miles must be
+intended.
+
+Other writers give estimates differing considerably from those just
+cited. The latest computations I have seen are those in the first volume
+of Kremer's _AEgypten_, 1863. This author (pp. 6, 7) assigns to the Delta
+an area of 200 square German geographical miles (fifteen to the degree);
+to all Lower Egypt, including, of course, the Delta, 400 such miles.
+These numbers are equal, respectively, to 4,239 and 8,478 square statute
+miles, and the great lagoons are embraced in the areas computed. Upper
+Egypt (above Cairo) is said (p. 11) to contain 4,000,000 feddan of
+_culturflaeche_, or cultivable land. The feddan is stated (p. 37) to
+contain 7,333 square piks, the pik being 75 centimetres, and it
+therefore corresponds almost exactly to the English acre. Hence,
+according to Kremer, the cultivable soil of Upper Egypt is 6,250 square
+statute miles, or twice as much as the whole area of the valley between
+Syene and the bifurcation of the Nile, according to Smith's _Dictionary
+of Greek and Roman Geography_. I suspect that 4,000,000 feddan is
+erroneously given as the cultivable area of Upper Egypt alone, when in
+fact it should be taken for the arable surface of both Lower and Upper
+Egypt; for from the statistical tables in the same volume, it appears
+that 3,317,125 feddan, or 5,253 square statute miles, were cultivated,
+in both geographical divisions, in the year referred to in the tables,
+the date of which is not stated.
+
+The area which the Nile would now cover at high water, if left to
+itself, is greater than in ancient times, because the bed of the river
+has been elevated, and consequently the lateral spread of the inundation
+increased. See SMITH'S _Dictionary of Geography_, article "AEgyptus." But
+the industry of the Egyptians in the days of the Pharaohs and the
+Ptolomies carried the Nile-water to large provinces which have now been
+long abandoned and have relapsed into the condition of a desert.
+"Anciently," observes the writer of the article "Egypt" in Smith's
+_Dictionary of the Bible_, "2,735 square miles more [about 3,700 square
+statute miles] may have been cultivated. In the best days of Egypt,
+probably all the land was cultivated that could be made available for
+agricultural purposes, and hence we may estimate the ancient arable area
+of that country at not less than 11,000 square statute miles, or fully
+double its present extent."
+
+[335] A canal has been constructed, and new ones are in progress, to
+convey water from the Nile to the city of Suez, and to various points on
+the line of the ship canal, with the double purpose of supplying fresh
+water to the inhabitants and laborers, and of irrigating the adjacent
+soil. The area of land which may be thus reclaimed and fertilized is
+very large, but the actual quantity which it will be found economically
+expedient to bring under cultivation cannot now be determined.
+
+[336] The so-called spring at Heliopolis is only a thread of water
+infiltrated from the Nile or the canals.
+
+[337] The date and the doum palm, the _sont_ and many other acacias, the
+caroub, the sycamore, and other trees, grow well in Egypt without
+irrigation, and would doubtless spread through the entire valley in a
+few years.
+
+[338] Wilkinson has shown that the cultivable soil of Egypt has not been
+diminished by encroachment of the desert sands, or otherwise, but that,
+on the contrary, it must have been increased since the age of the
+Pharaohs. The Gotha _Almanac_ for 1862 states the population of Egypt in
+1859 at 5,125,000 souls; but this must be a great exaggeration, even
+supposing the estimate to include the inhabitants of Nubia, and of much
+other territory not geographically belonging to Egypt. In general, the
+population of that country has been estimated at something more than
+three millions, or about six hundred to the square mile; but with a
+better government and better social institutions, the soil would sustain
+a much greater number, and in fact it is believed that in ancient times
+its inhabitants were twice, perhaps even thrice, as numerous as at
+present.
+
+Wilkinson (_Handbook for Travellers in Egypt_, p. 10) observes that the
+total population, which two hundred years ago was estimated at
+4,000,000, amounted till lately only to about 1,800,000 souls, having
+been reduced since 1800 from 2,500,000 to that number.
+
+[339] Ritter supposes Egypt to have been a sandy desert when it was
+first occupied by man. "The first inhabitant of the sandy valley of the
+Nile was a desert dweller, as his neighbors right and left, the Libyan,
+the nomade Arab, still are. But the civilized people of Egypt
+transformed, by canals, the waste into the richest granary of the world;
+they liberated themselves from the shackles of the rock and sand desert,
+in the midst of which, by a wise distribution of the fluid through the
+solid geographical form, by irrigation in short, they created a region
+of culture most rich in historical monuments."--_Einleitung zur
+allgemeinen vergleichenden Geographie_, pp. 165, 166.
+
+This view seems to me highly improbable; for though, by canals and
+embankments, man has done much to modify the natural distribution of the
+waters of the Nile, and possibly has even transferred its channel from
+one side of the valley to the other, yet the annual inundation is not
+his work, and the river must have overflowed its banks and carried
+spontaneous vegetation with its waters, as well before as since Egypt
+was first occupied by the human family. There is, indeed, some reason to
+suppose that man lived upon the banks of the Nile when its channel was
+much lower, and the spread of its inundations much narrower than at
+present; but wherever its flood reached, there the forest would
+propagate itself, and its shores are much more likely to have been
+morasses than sands.
+
+[340] _Memorie sui progetti per l'estensione dell' Irrigazione, etc., il
+Politecnico_, for January, 1863, p. 6.
+
+[341] NIEL, _L'Agriculture des Etats Sardes_, p. 232.
+
+[342] NIEL, _Agriculture des Etats Sardes_, p. 237. Lombardini's
+computation just given allows eighty-one cubic metres per day to the
+hectare, which, supposing the season of irrigation to be one hundred
+days, is equal to a precipitation of thirty-two inches. But in Lombardy,
+water is applied to some crops during a longer period than one hundred
+days; and in the _marcite_ it flows over the ground even in winter.
+
+According to Boussingault (_Economie Rurale_, ii, p. 246) grass grounds
+ought to receive, in Germany, twenty-one centimetres of water per week,
+and with less than half that quantity it is not advisable to incur the
+expense of supplying it. The ground is irrigated twenty-five or thirty
+times, and if the full quantity of twenty-one centimetres is applied, it
+receives about two hundred inches of water, or six times the total
+amount of precipitation. Puvis, quoted by Boussingault, after much
+research comes to the conclusion that a proper quantity is twenty
+centimetres applied twenty-five or thirty times, which corresponds with
+the estimate just stated. Puvis adds--and, as our author thinks, with
+reason--that this amount might be doubled without disadvantage.
+
+Boussingault observes that rain water is vastly more fertilizing than
+the water of irrigating canals, and therefore the supply of the latter
+must be greater. This is explained partly by the different character of
+the substances held in solution or suspension by the waters of the earth
+and of the sky, partly by the higher temperature of the latter, and,
+possibly, partly also by the mode of application--the rain being finely
+divided in its fall or by striking plants on the ground, river water
+flowing in a continuous sheet.
+
+The temperature of the water is thought even more important than its
+composition. The sources which irrigate the _marcite_ of
+Lombardy--meadows so fertile that less than an acre furnishes grass for
+a cow the whole year--are very warm. The ground watered by them never
+freezes, and a first crop, for soiling, is cut from it in January or
+February. The Canal Cavour, just now commenced--which is to take its
+supply from the Po at Chivasso, fourteen or fifteen miles below
+Turin--will furnish water of much higher fertilizing power than that
+derived from the Dora Baltea and the Sesia, both because it is warmer,
+and because it transports a more abundant and a richer sediment than the
+latter streams, which are fed by Alpine icefields and melting snows, and
+which flow, for long distances, in channels ground smooth and bare by
+ancient glaciers, and not now contributing much vegetable mould or fine
+slime to their waters.
+
+[343] It belongs rather to agriculture than to geography to discuss the
+quality of the crops obtained by irrigation, or the permanent effects
+produced by it on the productiveness of the soil. There is no doubt,
+however, that all crops which can be raised without watering are
+superior in flavor and in nutritive power to those grown by the aid of
+irrigation. Garden vegetables, particularly, profusely watered, are so
+insipid as to be hardly eatable. Wherever irrigation is practised, there
+is an almost irresistible tendency, especially among ignorant
+cultivators, to carry it to excess; and in Piedmont and Lombardy, if the
+supply of water is abundant, it is so liberally applied as sometimes not
+only to injure the quality of the product, but to drown the plants and
+diminish the actual weight of the crop.
+
+Professor Liebig, in his _Modern Agriculture_, says: "There is not to be
+found in chemistry a more wonderful phenomenon, one which more confounds
+all human wisdom, than is presented by the soil of a garden or field. By
+the simplest experiment, any one may satisfy himself that rain water
+filtered through field or garden soil does not dissolve out a trace of
+potash, silicic acid, ammonia, or phosphoric acid. The soil does not
+give up to the water one particle of the food of plants which it
+contains. The most continuous rains cannot remove from the field, except
+mechanically, any of the essential constituents of its fertility."
+
+"The soil not only retains firmly all the food of plants which is
+actually in it, but its power to preserve all that may be useful to them
+extends much farther. If rain or other water holding in solution
+ammonia, potash, and phosphoric and silicic acids, be brought in contact
+with soil, these substances disappear almost immediately from the
+solution; the soil withdraws them from the water. Only such substances
+are completely withdrawn by the soil as are indispensable articles of
+food for plants; all others remain wholly or in part in solution."
+
+The first of the paragraphs just quoted is not in accordance with the
+alleged experience of agriculturists in those parts of Italy where
+irrigation is most successfully applied. They believe that the
+constituents of vegetable growth are washed out of the soil by excessive
+and long-continued watering. They consider it also established as a fact
+of observation, that water which has flowed through or over rich ground
+is far more valuable for irrigation than water from the same source,
+which has not been impregnated with fertilizing substances by passing
+through soils containing them; and, on the other hand, that water, rich
+in the elements of vegetation, parts with them in serving to irrigate a
+poor soil, and is therefore less valuable as a fertilizer of lower
+grounds to which it may afterward be conducted.
+
+The practice of irrigation--except in mountainous countries where
+springs and rivulets are numerous--is attended with very serious
+economical, social, and political evils. The construction of canals and
+their immensely ramified branches, and the grading and scarping of the
+ground to be watered, are always expensive operations, and they very
+often require an amount of capital which can be commanded only by the
+state, by moneyed corporations, or by very wealthy proprietors; the
+capacity of the canals must be calculated with reference to the area
+intended to be irrigated, and when they and their branches are once
+constructed, it is very difficult to extend them, or to accommodate any
+of their original arrangements to changes in the condition of the soil,
+or in the modes or objects of cultivation; the flow of the water being
+limited by the abundance of the source or the capacity of the canals,
+the individual proprietor cannot be allowed to withdraw water at will,
+according to his own private interest or convenience, but both the time
+and the quantity of supply must be regulated by a general system
+applicable, as far as may be, to the whole area irrigated by the same
+canal, and every cultivator must conform his industry to a plan which
+may be quite at variance with his special objects or with his views of
+good husbandry. The clashing interests and the jealousies of proprietors
+depending on the same means of supply are a source of incessant
+contention and litigation, and the caprices or partialities of the
+officers who control, or of contractors who farm the canals, lead not
+unfrequently to ruinous injustice toward individual landholders. These
+circumstances discourage the division of the soil into small properties,
+and there is a constant tendency to the accumulation of large estates of
+irrigated land in the hands of great capitalists, and consequently to
+the dispossession of the small cultivators, who pass from the condition
+of owners of the land to that of hireling tillers. The farmers are no
+longer yeomen, but peasants. Having no interest in the soil which
+composes their country, they are virtually expatriated, and the middle
+class, which ought to constitute the real physical and moral strength of
+the land, ceases to exist as a rural estate, and is found only among the
+professional, the mercantile, and the industrial population of the
+cities.
+
+[344] BOUSSINGAULT, _Economie Rurale_, ii, pp. 248, 249.
+
+[345] The cultivation of rice is so prejudicial to health everywhere
+that nothing but the necessities of a dense population can justify the
+sacrifice of life it costs in countries where it is pursued.
+
+It has been demonstrated by actual experiment, that even in Mississippi,
+cotton can be advantageously raised by the white man without danger to
+health; and in fact, a great deal of the cotton brought to the Vicksburg
+market for some years past has been grown exclusively by white labor.
+There is no reason why the cultivation of cotton should be a more
+unhealthy occupation in America than it is in other countries where it
+was never dreamed of as dangerous, and no well-informed American, in the
+Slave States or out of them, believes that the abolition of slavery in
+the South would permanently diminish the cotton crop of those States.
+
+[346] _L'Italie a propos de l'Exposition de Paris_, p. 92.
+
+[347] The very valuable memoirs of Lombardini, _Cenni idrografi sulla
+Lombardia, Intorno al sistema idraulico del Po_, and other papers on
+similar subjects, were published in periodicals little known out of
+Italy; and the _Idraulica Pratica_ of Mari has not, I believe, been
+translated into French or English. These works, and other sources of
+information equally inaccessible out of Italy, have been freely used by
+Baumgarten, in a memoir entitled _Notice sur les Rivieres de la
+Lombardie_, in the _Annales des Ponts et Chaussees_, 1847, 1er semestre,
+pp. 129 _et seqq._, and by Dumont, _Des Travaux Publics dans leurs
+Rapports avec l'Agriculture_, note, viii, pp. 269 _et seqq._ For the
+convenience of my readers, I shall use these two articles instead of the
+original authorities on which they are founded.
+
+[348] Sir John F. W. Herschel, citing Talabot as his authority,
+_Physical Geography_ (24).
+
+In an elaborate paper on "Irrigation," printed in the _United States
+Patent Report_ for 1860, p. 169, it is stated that the volume of water
+poured into the Mediterranean by the Nile in twenty-four hours, at low
+water, is 150,566,392,368 cubic metres; at high water, 705,514,667,440
+cubic metres. Taking the mean of these two numbers, the average daily
+delivery of the Nile would be 428,081,059,808 cubic metres, or more than
+550,000,000,000 cubic yards. There is some enormous mistake, probably a
+typographical error, in this statement, which makes the delivery of the
+Nile seventeen hundred times as great as computed by Talabot, and many
+times more than any physical geographer has ever estimated the quantity
+supplied by all the rivers on the face of the globe.
+
+[349] The Drac, a torrent emptying into the Isere a little below
+Grenoble, has discharged 5,200, the Isere, which receives it,
+7,800 cubic yards, and the Durance an equal quantity, per
+second.--MONTLUISANT, _Note sur les Dessechements, etc., Annales
+des Ponts et Chaussees_, 1833, 2me semestre, p. 288.
+
+The floods of some other French rivers scarcely fall behind those of the
+Rhone. The Loire, above Roanne, has a basin of 2,471 square miles, or
+about twice and a half the area of that of the Ardeche. In some of its
+inundations it has delivered above 9,500 cubic yards per
+second.--BELGRAND, _De l'Influence des Forets, etc., Annales des Ponts
+et Chaussees_, 1854, 1er semestre, p. 15, note.
+
+[350] The original forests in which the basin of the Ardeche was rich
+have been rapidly disappearing, for many years, and the terrific
+violence of the inundations which are now laying it waste is ascribed,
+by the ablest investigators, to that cause. In an article inserted in
+the _Annales Forestieres_ for 1843, quoted by Hohenstein, _Der Wald_, p.
+177, it is said that about one third of the area of the department had
+already become absolutely barren, in consequence of clearing, and that
+the destruction of the woods was still going on with great rapidity. New
+torrents were constantly forming, and they were estimated to have
+covered more than 70,000 acres of good land, or one eighth of the
+surface of the department, with sand and gravel.
+
+[351] "There is no example of a coincidence between great floods of the
+Ardeche and of the Rhone, all the known inundations of the former having
+taken place when the latter was very low."--MARDIGNY, _Memoire sur les
+Inondations des Rivieres de l'Ardeche_, p. 26.
+
+I take this occasion to acknowledge myself indebted to the interesting
+memoir just quoted for all the statements I make respecting the floods
+of the Ardeche, except the comparison of the volume of its waters with
+that of the Nile, and the computation with respect to the capacity
+required for reservoirs to be constructed in its basin.
+
+[352] In some cases where the bed of rapid Alpine streams is composed of
+very hard rock--as is the case in many of the valleys once filled by
+ancient glaciers--and especially where they are fed by glaciers not
+overhung by crumbling cliffs, the channel may remain almost unchanged
+for centuries. This is observable in many of the tributaries of the Dora
+Baltea, which drains the valley of the Aosta. Several of these small
+rivers are spanned by more or less perfect Roman bridges--one of which,
+that over the Lys at Pont St. Martin, is still in good repair and in
+constant use. An examination of the rocks on which the abutments of this
+and some other similar structures are founded, and of the channels of
+the rivers they cross, shows that the beds of the streams cannot have
+been much elevated or depressed since the bridges were built. In other
+cases, as at the outlet of the Val Tournanche at Chatillon, where a
+single rib of a Roman bridge still remains, there is nothing to forbid
+the supposition that the deep excavation of the channel may have been
+partly effected at a much later period. See _App._, No. 45.
+
+[353] _Memoire sur les Inondations des Rivieres de l'Ardeche_, p. 16.
+"The terrific roar, the thunder of the raging torrents proceeds
+principally from the stones which are rolled along in the bed of the
+stream. This movement is attended with such powerful attrition that, in
+the Southern Alps, the atmosphere of valleys where the limestone
+contains bitumen, has, at the time of floods, the marked bituminous
+smell produced by rubbing pieces of such limestone together."--WESSELY,
+_Die Oesterreichischien Alpenlaender_, i, p. 113. See _Appendix_, No. 48.
+
+[354] FRISI, _Del modo di regolare i Fiumi e i Torrenti_, pp. 4-19.
+
+[355] SURELL, _Etude sur les Torrents_, pp. 31-36.
+
+[356] CHAMPION, _Les Inondations en France_, iii, p. 156, note.
+
+[357] Notwithstanding this favorable circumstance, the damage done by
+the inundation of 1840 in the valley of the Rhone was estimated at
+seventy-two millions of francs.--CHAMPION, _Les Inondations en France_,
+iv, p. 124.
+
+Several smaller floods of the Rhone, experienced at a somewhat earlier
+season of the year in 1846, occasioned a loss of forty-five millions of
+francs. "What if," says Dumont, "instead of happening in October, that
+is between harvest and seedtime, they had occurred before the crops were
+secured? The damage would have been counted by hundreds of
+millions."--_Des Travaux Publics_, p. 99, note.
+
+[358] TROY, _Etude sur le Reboisement des Montagnes_, Sec.Sec. 6, 7, 21.
+
+[359] For accounts of damage from the bursting of reservoirs, see
+VALLEE, _Memoire sur les Reservoirs d'Alimentation des Canaux, Annales
+des Ponts et Chaussees_, 1833, 1er semestre, p. 261.
+
+[360] Some geographical writers apply the term _bifurcation_ exclusively
+to this intercommunication of rivers; others, with more etymological
+propriety, use it to express the division of great rivers into branches
+at the head of their deltas. A technical term is wanting to designate
+the phenomenon mentioned in the text.
+
+[361] MARDIGNY, _Memoire sur les Inondations de l'Ardeche_, p. 13.
+
+[362] In the case of rivers flowing through wide alluvial plains and
+much inclined to shift their beds, like the Po, the embankments often
+leave a very wide space between them. The dikes of the Po are sometimes
+three or four miles apart.--BAUMGARTEN, after LOMBARDINI, _Annales des
+Ponts et Chaussees_, 1847, 1er semestre, p. 149.
+
+[363] It appears from the investigations of Lombardini that the rate of
+elevation of the bed of the Po has been much exaggerated by earlier
+writers, and in some parts of its course the change is so slow that its
+level may be regarded as nearly constant.--BAUMGARTEN, volume before
+cited, pp. 175, et seqq. See _Appendix_, No. 49.
+
+If the western coast of the Adriatic is undergoing a secular depression,
+as many circumstances concur to prove, the sinking of the plain near the
+coast may both tend to prevent the deposit of sediment in the river bed
+by increasing the velocity of its current, and compensate the elevation
+really produced by deposits, so that no sensible elevation would result,
+though much gravel and slime might be let fall.
+
+[364] To secure the city of Sacramento in California from the
+inundations to which it is subject, a dike or levee was built upon the
+bank of the river and raised to an elevation above that of the highest
+known floods, and it was connected, below the town, with grounds lying
+considerably above the river. On one occasion a breach in the dike
+occurred above the town at a very high stage of the flood. The water
+poured in behind it, and overflowed the lower part of the city, which
+remained submerged for some time after the river had retired to its
+ordinary level, because the dike, which had been built to keep the water
+_out_, now kept it _in_.
+
+According to Arthur Young, on the lower Po, where the surface of the
+river has been elevated much above the level of the adjacent fields by
+diking, the peasants in his time frequently endeavored to secure their
+grounds against threatened devastation through the bursting of the
+dikes, by crossing the river when the danger became imminent and opening
+a cut in the opposite bank, thus saving their own property by flooding
+their neighbors'. He adds, that at high water the navigation of the
+river was absolutely interdicted, except to mail and passenger boats,
+and that the guards fired upon all others; the object of the prohibition
+being to prevent the peasants from resorting to this measure of
+self-defence.--_Travels in Italy and Spain_, Nov. 7, 1789.
+
+In a flood of the Po in 1839, a breach of the embankment took place at
+Bonizzo. The water poured through and inundated 116,000 acres, or 181
+square miles, of the plain, to the depth of from twenty to twenty-three
+feet in its lower parts.--BAUMGARTEN, after LOMBARDINI, volume before
+cited, p. 152.
+
+[365] MOYENS _de forcer les Torrents de rendre une partie du sol qu'ils
+ravagent, et d'empecher les grandes Inondations_.
+
+[366] The effect of trees and other detached obstructions in checking
+the flow of water is particularly noticed by Palissy in his essay on
+_Waters and Fountains_, p. 173, edition of 1844. "There be," says he,
+"in divers parts of France, and specially at Nantes, wooden bridges,
+where, to break the force of the waters and of the floating ice, which
+might endamage the piers of the said bridges, they have driven upright
+timbers into the bed of the rivers above the said piers, without the
+which they should abide but little. And in like wise, the trees which be
+planted along the mountains do much deaden the violence of the waters
+that flow from them."
+
+[367] I do not mean to say that all rivers excavate their own valleys,
+for I have no doubt that in the majority of cases such depressions of
+the surface originate in higher geological causes, and hence the valley
+makes the river, not the river the valley. But even if we suppose a
+basin of the hardest rock to be elevated at once, completely formed,
+from the submarine abyss where it was fashioned, the first shower of
+rain that falls upon it after it rises to the air, while its waters will
+follow the lowest lines of the surface, will cut those lines deeper, and
+so on with every successive rain. The disintegrated rock from the upper
+part of the basin forms the lower by alluvial deposit, which is
+constantly transported farther and farther until the resistance of
+gravitation and cohesion balances the mechanical force of the running
+water. Thus plains, more or less steeply inclined, are formed, in which
+the river is constantly changing its bed, according to the perpetually
+varying force and direction of its currents, modified as they are by
+ever-fluctuating conditions. Thus the Po is said to have long inclined
+to move its channel southward in consequence of the superior mechanical
+force of its northern affluents. A diversion of these tributaries from
+their present beds, so that they should enter the main stream at other
+points and in different directions, might modify the whole course of
+that great river. But the mechanical force of the tributary is not the
+only element of its influence on the course of the principal stream. The
+deposits it lodges in the bed of the latter, acting as simple
+obstructions or causes of diversion, are not less important agents of
+change.
+
+[368] The distance to which a new obstruction to the flow of a river,
+whether by a dam or by a deposit in its channel, will retard its
+current, or, in popular phrase, "set back the water," is a problem of
+more difficult practical solution than almost any other in hydraulics.
+The elements--such as straightness or crookedness of channel, character
+of bottom and banks, volume and previous velocity of current, mass of
+water far above the obstruction, extraordinary drought or humidity of
+seasons, relative extent to which the river may be affected by the
+precipitation in its own basin, and by supplies received through
+subterranean channels from sources so distant as to be exposed to very
+different meteorological influences, effects of clearing and other
+improvements always going on in new countries--are all extremely
+difficult, and some of them impossible, to be known and measured. In the
+American States, very numerous watermills have been erected within a few
+years, and there is scarcely a stream in the settled portion of the
+country which has not several milldams upon it. When a dam is raised--a
+process which the gradual diminution of the summer currents renders
+frequently necessary--or when a new dam is built, it often happens that
+the meadows above are flowed, or that the retardation of the stream
+extends back to the dam next above. This leads to frequent lawsuits.
+From the great uncertainty of the facts, the testimony is more
+conflicting in these than in any other class of cases, and the obstinacy
+with which "water causes" are disputed has become proverbial.
+
+The subterranean courses of the waters form a subject very difficult of
+investigation, and it is only recently that its vast importance has been
+recognized. The interesting observations of Schmidt on the caves of the
+Karst and their rivers throw much light on the underground hydrography
+of limestone districts, and serve to explain how, in the low peninsula
+of Florida, rivers, which must have their sources in mountains a hundred
+or more miles distant, can pour out of the earth in currents large
+enough to admit of steamboat navigation to their very basins of
+eruption. Artesian wells are revealing to us the existence of
+subterranean lakes and rivers sometimes superposed one above another in
+successive sheets; but the still more important subject of the
+absorption of water by earth and its transmission by infiltration is yet
+wrapped in great obscurity.
+
+[369] The sediment of the Po has filled up some lagoons and swamps in
+its delta, and converted them into comparatively dry land; but, on the
+other hand, the retardation of the current from the lengthening of its
+course, and the diminution of its velocity by the deposits at its mouth,
+have forced its waters at some higher points to spread in spite of
+embankments, and thus fertile fields have been turned into unhealthy and
+unproductive marshes.--See BOTTER, _Sulla condizione dei Terreni
+Maremmani nel Ferrarese. Annali di Agricoltura, etc._, Fasc. v, 1863.
+
+[370] Deep borings have not detected any essential difference in the
+quantity or quality of the deposits of the Nile for forty or fifty, or,
+as some compute, for a hundred centuries. From what vast store of rich
+earth does this river derive the three or four inches of fertilizing
+material which it spreads over the soil of Egypt every hundred years?
+Not from the White Nile, for that river drops nearly all its suspended
+matter in the broad expansions and slow current of its channel south of
+the tenth degree of north latitude. Nor does it appear that much
+sediment is contributed by the Bahr-el-Azrek, which flows through
+forests for a great part of its course. I have been informed by an old
+European resident of Egypt who is very familiar with the Upper Nile,
+that almost the whole of the earth with which its waters are charged is
+brought down by the Takazze.
+
+[371] It is very probably true that, as Lombardini supposes, the plain
+of Lombardy was anciently covered with forests and morasses (Baumgarten,
+l. c. p. 156); but, had the Po remained unconfined, its deposits would
+have raised its banks as fast as its bed, and there is no obvious reason
+why this plain should be more marshy than other alluvial flats traversed
+by great rivers. Its lower course would possibly have become more marshy
+than at present, but the banks of its middle and upper course would have
+been in a better condition for agricultural use than they now are.
+
+[372] From daily measurements during a period of fourteen years--1827 to
+1840--the mean delivery of the Po at Ponte Lagoscuro, below the entrance
+of its last tributary, is found to be 1,720 cubic metres, or 60,745
+cubic feet, per second. Its smallest delivery is 186 cubic metres, or
+6,569 cubic feet, its greatest 5,156 cubic metres, or 182,094 cubic
+feet.--BAUMGARTEN, following LOMBARDINI, volume before cited, p. 159.
+
+The average delivery of the Nile being 101,000 cubic feet per second, it
+follows that the Po contributes to the Adriatic six tenths as much water
+as the Nile to the Mediterranean--a result which will surprise most
+readers.
+
+[373] We are quite safe in supposing that the valley of the Nile has
+been occupied by man at least 5,000 years. The dates of Egyptian
+chronology are uncertain, but I believe no inquirer estimates the age of
+the great pyramids at less than forty centuries, and the construction of
+such works implies an already ancient civilization.
+
+[374] There are many dikes in Egypt, but they are employed in but a very
+few cases to exclude the waters of the inundation. Their office is to
+retain the water received at high Nile into the inclosures formed by
+them until it shall have deposited its sediment or been drawn out for
+irrigation; and they serve also as causeways for interior communication
+during the floods. The Egyptian dikes, therefore, instead of forcing the
+river, like those of the Po, to transport its sediment to the sea, help
+to retain the slime, which, if the flow of the current over the land
+were not obstructed, might be carried back into the channel, and at last
+to the Mediterranean.
+
+[375] The Mediterranean front of the Delta may be estimated at one
+hundred and fifty miles in length. Two cubic miles of earth would more
+than fill up the lagoons on the coast, and the remaining ten, even
+allowing the mean depth of the water to be twenty fathoms, which is
+beyond the truth, would have been sufficient to extend the coast line
+about three miles farther seaward, and thus, including the land gained
+by the filling up of the lagoons, to add more than five hundred square
+miles to the area of Egypt. Nor is this all; for the retardation of the
+current, by lengthening the course and consequently diminishing the
+inclination of the channel, would have increased the deposit of
+suspended matter, and proportionally augmented the total effect of the
+embankment.
+
+[376] For the convenience of navigation, and to lessen the danger of
+inundation by giving greater directness, and, of course, rapidity to the
+current, bends in rivers are sometimes cut off and winding channels made
+straight. This process has the same general effects as diking, and
+therefore cannot be employed without many of the same results.
+
+This practice has often been resorted to on the Mississippi with
+advantage to navigation, but it is quite another question whether that
+advantage has not been too dearly purchased by the injury to the banks
+at lower points. If we suppose a river to have a navigable course of
+1,600 miles as measured by its natural channel, with a descent of 800
+feet, we shall have a fall of six inches to the mile. If the length of
+channel be reduced to 1,200 miles by cutting off bends, the fall is
+increased to eight inches per mile. The augmentation of velocity
+consequent upon this increase of inclination is not computable without
+taking into account other elements, such as depth and volume of water,
+diminution of direct resistance, and the like, but in almost any
+supposable case, it would be sufficient to produce great effects on the
+height of floods, the deposit of sediment in the channel, on the shores,
+and at the outlet, the erosion of banks and other points of much
+geographical importance.
+
+The Po, in those parts of its course where the embankments leave a wide
+space between, often cuts off bends in its channel and straightens its
+course. These short cuts are called _salti_, or leaps, and sometimes
+reduce the distance between their termini by several miles. In 1777, the
+salto of Cottaro shortened a distance of 7,000 metres by 5,000, or, in
+other words, reduced the length of the channel more than three miles;
+and in 1807 and 1810 the two salti of Mezzanone effected a reduction of
+distance to the amount of between seven and eight miles.--BAUMGARTEN, l.
+c. p. 38.
+
+[377] The fact, that the mixing of salt and fresh water in coast marshes
+and lagoons is deleterious to the sanitary condition of the vicinity,
+seems almost universally admitted, though the precise reason why a
+mixture of both should be more injurious than either alone, is not
+altogether clear. It has been suggested that the admission of salt water
+to the lagoons and rivers kills many fresh water plants and animals,
+while the fresh water is equally fatal to many marine organisms, and
+that the decomposition of the remains originates poisonous miasmata.
+Other theories however have been proposed. The whole subject is fully
+and ably discussed by Dr. Salvagnoli Marchetti in the appendix to his
+valuable _Rapporto sul Bonificamento delle Maremme Toscane_. See also
+the _Memorie Economico-Statistiche sulle Maremme Toscane_, of the same
+author.
+
+[378] This curious fact is thus stated in the preface to Fossombroni
+(_Memorie sopra la Val di Chiana_, edition of 1835, p. xiii), from which
+also I borrow most of the data hereafter given with respect to that
+valley: "It is perhaps not universally known, that the swallows, which
+come from the north [south] to spend the summer in our climate, do not
+frequent marshy districts with a malarious atmosphere. A proof of the
+restoration of salubrity in the Val di Chiana is furnished by these
+aerial visitors, which had never before been seen in those low grounds,
+but which have appeared within a few years at Forano and other points
+similarly situated."
+
+Is the air of swamps destructive to the swallows, or is their absence in
+such localities merely due to the want of human habitations, near which
+this half-domestic bird loves to breed, perhaps because the house fly
+and other insects which follow man are found only in the vicinity of his
+dwellings?
+
+In almost all European countries, the swallow is protected, by popular
+opinion or superstition, from the persecution to which almost all other
+birds are subject. It is possible that this respect for the swallow is
+founded upon ancient observation of the fact just stated on the
+authority of Fossombroni. Ignorance mistakes the effect for the cause,
+and the absence of this bird may have been supposed to be the occasion,
+not the consequence, of the unhealthiness of particular localities. This
+opinion once adopted, the swallow would become a sacred bird, and in
+process of time fables and legends would be invented to give additional
+sanction to the prejudices which protected it. The Romans considered the
+swallow as consecrated to the Penates, or household gods, and according
+to Peretti (_Le Serate del Villaggio_, p. 168) the Lombard peasantry
+think it a sin to kill them, because they are _le gallinelle del
+Signore_, the chickens of the Lord.
+
+The following little Tuscan _rispetto_ from Gradi (_Racconti Popolari_,
+p. 33) well expresses the feeling of the peasantry toward this bird:
+
+ O rondinella che passi lo mare
+ Torna 'ndietro, vo' dirti du' parole;
+ Dammi 'na penna delle tue bell' ale,
+ Vo' scrivere 'na lettera al mi' amore;
+ E quando l' avro scritta 'n carta bella,
+ Ti rendero la penna, o rondinella;
+ E quando l' avro scritta 'n carta bianca,
+ Ti rendero la penna che ti manca;
+ E quando l' avro scritta in carta d' oro,
+ Ti rendero la penna al tuo bel volo.
+
+ O swallow, that fliest beyond the sea,
+ Turn back! I would fain have a word with thee.
+ A feather oh grant, from thy wing so bright!
+ For I to my sweetheart a letter would write;
+ And when it is written on paper fine
+ I'll give thee, O swallow, that feather of thine;
+ --On paper so white, and I'll give thee back,
+ O pretty swallow, the pen thou dost lack;
+ --On paper of gold, and then I'll restore
+ To thy beautiful pinion the feather once more.
+
+Popular traditions and superstitions are so closely connected with
+localities, that, though an emigrant people may carry them to a foreign
+land, they seldom survive a second generation. The swallow, however, is
+still protected in New England by prejudices of transatlantic origin;
+and I remember hearing, in my childhood, that if the swallows were
+killed, the cows would give bloody milk.
+
+[379] MOROZZI, _Dello stato antico e moderno del fiume Arno_, ii, p. 42.
+
+[380] MOROZZI, _Dello stato, etc., dell' Arno_, ii, pp. 39, 40.
+
+[381] Torricelli thus expressed himself on this point: "If we content
+ourselves with what nature has made practicable to human industry, we
+shall endeavor to control, as far as possible, the outlets of these
+streams, which, by raising the bed of the valley with their deposits,
+will realize the fable of the Tagus and the Pactolus, and truly roll
+golden sands for him that is wise enough to avail himself of
+them."--FOSSOMBRONI, _Memorie sopra la Val di Chiana_, p. 219.
+
+[382] Arrian observes that at the junction of the Hydaspes and the
+Acesines, both of which are described as wide streams, "one very narrow
+river is formed of two confluents, and its current is very
+swift."--ARRIAN, _Alex. Anab._, vi, 4.
+
+[383] This difficulty has been remedied as to one important river of the
+Maremma, the Pecora, by clearings recently executed along its upper
+course. "The condition of this marsh and of its affluents are now,
+November, 1859, much changed, and it is advisable to prosecute its
+improvement by deposits. In consequence of the extensive felling of the
+woods upon the plains, hills, and mountains of the territory of Massa
+and Scarlino, within the last ten years, the Pecora and other affluents
+of the marsh receive, during the rains, water abundantly charged with
+slime, so that the deposits within the first division of the marsh are
+already considerable, and we may now hope to see the whole marsh and
+pond filled up in a much shorter time than we had a right to expect
+before 1850. This circumstance totally changes the terms of the
+question, because the filling of the marsh and pond, which then seemed
+almost impossible on account of the small amount of sediment deposited
+by the Pecora, has now become practicable."--SALVAGNOLI, _Rapporto sul
+Bonificamento delle Maremme Toscane_, pp. li, lii.
+
+The annual amount of sediment brought down by the rivers of the Maremma
+is computed at more than 12,000,000 cubic yards, or enough to raise an
+area of four square miles one yard. Between 1830 and 1859 more than
+three times that quantity was deposited in the marsh and shoal water
+lake of Castiglione alone.--SALVAGNOLI, _Raccolta di Documenti_, pp. 74,
+75.
+
+[384] The tide rises ten inches on the coast of Tuscany. See Memoir by
+FANTONI, in the appendix to SALVAGNOLI, _Rapporto_, p. 189.
+
+On the tides of the Mediterranean, see BOeTTGER, _Das Mittelmeer_, p.
+190. Not having Admiral Smyth's Mediterranean--on which Boettger's work
+is founded--at hand, I do not know how far credit is due to the former
+author for the matter contained in the chapter referred to.
+
+[385] In Catholic countries, the discipline of the church requires a
+_meagre_ diet at certain seasons, and as fish is not flesh, there is a
+great demand for that article of food at those periods. For the
+convenience of monasteries and their patrons, and as a source of
+pecuniary emolument to ecclesiastical establishments and sometimes to
+lay proprietors, great numbers of artificial fish ponds were created
+during the Middle Ages. They were generally shallow pools formed by
+damming up the outlet of marshes, and they were among the most fruitful
+sources of endemic disease, and of the peculiar malignity of the
+epidemics which so often ravaged Europe in those centuries. These ponds,
+in religious hands, were too sacred to be infringed upon for sanitary
+purposes, and when belonging to powerful lay lords they were almost as
+inviolable. The rights of fishery were a standing obstacle to every
+proposal of hydraulic improvement, and to this day large and fertile
+districts in Southern Europe remain sickly and almost unimproved and
+uninhabited, because the draining of the ponds upon them would reduce
+the income of proprietors who derive large profits by supplying the
+faithful, in Lent, with fish, and with various species of waterfowl
+which, though very fat, are, ecclesiastically speaking, meagre.
+
+[386] Macchiavelli advised the Government of Tuscany "to provide that
+men should restore the wholesomeness of the soil by cultivation, and
+purify the air by fires."--SALVAGNOLI, _Memorie_, p. 111.
+
+[387] GIORGINI, _Sur les causes de l'Insalubrite de l'air dans le
+voisinage des marais, etc., lue a l'Academie des Sciences a Paris_, le
+12 Juillet, 1825. Reprinted in SALVAGNOLI, _Rapporto, etc._, appendice,
+p. 5, _et seqq._
+
+[388] See the careful estimates of ROSET, _Moyens de forcer les
+Torrents, etc._, pp. 42, 44.
+
+[389] Rivers which transport sand, gravel, pebbles, heavy mineral matter
+in short, tend to raise their own beds; those charged only with fine,
+light earth, to cut them deeper. The prairie rivers of the West have
+deep channels, because the mineral matter they carry down is not heavy
+enough to resist the impulse of even a moderate current, and those
+tributaries of the Po which deposit their sediment in the lakes--the
+Ticino, the Adda, the Oglio, and the Mincio--flow, in deep cuts, for the
+same reason.--BAUMGARTEN, l. c., p. 132.
+
+[390] "The stream carries this mud, &c., at first farther to the east,
+and only lets it fall where the force of the current becomes weakened.
+This explains the continual advance of the land seaward along the Syrian
+coast, in consequence of which Tyre and Sidon no longer lie on the
+shore, but some distance inland. That the Nile contributes to this
+deposit may easily be seen, even by the unscientific observer, from the
+stained and turbid character of the water for many miles from its
+mouths. A somewhat alarming phenomenon was observed in this neighborhood
+in 1801, on board the English frigate Romulus, Captain Culverhouse, on a
+voyage from Acre to Abukir. Dr. E. D. Clarke, who was a passenger on
+board this ship, thus describes it:
+
+"'26th July.--To-day, Sunday, we accompanied the captain to the wardroom
+to dine, as usual, with his officers. While we were at table, we heard
+the sailors who were throwing the lead suddenly cry out: "Three and a
+half!" The captain sprang up, was on deck in an instant, and, almost at
+the same moment, the ship slackened her way, and veered about. Every
+sailor on board supposed she would ground at once. Meanwhile, however,
+as the ship came round, the whole surface of the water was seen to be
+covered with thick, black mud, which extended so far that it appeared
+like an island. At the same time, actual land was nowhere to be
+seen--not even from the masthead--nor was any notice of such a shoal to
+be found on any chart on board. The fact is, as we learned afterward,
+that a stratum of mud, stretching from the mouths of the Nile for many
+miles out into the open sea, forms a movable deposit along the Egyptian
+coast. If this deposit is driven forward by powerful currents, it
+sometimes rises to the surface, and disturbs the mariner by the sudden
+appearance of shoals where the charts lead him to expect a considerable
+depth of water. But these strata of mud are, in reality, not in the
+least dangerous. As soon as a ship strikes them they break up at once,
+and a frigate may hold her course in perfect safety where an
+inexperienced pilot, misled by his soundings, would every moment expect
+to be stranded.'"--BOeTTGER, _Das Mittelmeer_, pp. 188, 189.
+
+[391] The caves of Carniola receive considerable rivers from the surface
+of the earth, which cannot, in all cases, be identified with streams
+flowing out of them at other points, and like phenomena are not uncommon
+in other limestone countries.
+
+The cases are certainly not numerous where marine currents are known to
+pour continuously into cavities beneath the surface of the earth, but
+there is at least one well-authenticated instance of this sort--that of
+the mill streams at Argostoli in the island of Cephalonia. It had been
+long observed that the sea water flowed into several rifts and cavities
+in the limestone rocks of the coast, but the phenomenon has excited
+little attention until very recently. In 1833, three of the entrances
+were closed, and a regular channel, sixteen feet long and three feet
+wide, with a fall of three feet, was cut into the mouth of a larger
+cavity. The sea water flowed into this canal, and could be followed
+eighteen or twenty feet beyond its inner terminus, when it disappeared
+in holes and clefts in the rock.
+
+In 1858, the canal had been enlarged to the width of five feet and a
+half, and a depth of a foot. The water pours rapidly through the canal
+into an irregular depression and forms a pool, the surface of which is
+three or four feet below the adjacent soil, and about two and a half or
+three feet below the level of the sea. From this pool it escapes through
+several holes and clefts in the rock, and has not yet been found to
+emerge elsewhere.
+
+There is a tide at Argostoli of about six inches in still weather, but
+it is considerably higher with a south wind. I do not find it stated
+whether water flows through the canal into the cavity at low tide, but
+it distinctly appears that there is no refluent current, as of course
+there could not be from a basin so much below the sea. Mousson found the
+delivery through the canal to be at the rate of 24.88 cubic feet to the
+second; at what stage of the tide does not appear. Other mills of the
+same sort have been erected, and there appear to be several points on
+the coast where the sea flows into the land.
+
+Various hypotheses have been suggested to explain this phenomenon, some
+of which assume that the water descends to a great depth beneath the
+crust of the earth, but the supposition of a difference of level in the
+surface of the sea on the opposite sides of the island, which seems
+confirmed by other circumstances, is the most obvious method of
+explaining these singular facts. If we suppose the level of the water on
+one side of the island to be raised by the action of currents three or
+four feet higher than on the other, the existence of cavities and
+channels in the rock would easily account for a subterranean current
+beneath the island, and the apertures of escape might be so deep or so
+small as to elude observation. See _Aus der Natur_, vol. 19, pp. 129,
+_et seqq._ See _Appendix_, No. 53.
+
+[392] "The affluents received by the Seine below Rouen are so
+inconsiderable, that the augmentation of the volume of that river must
+be ascribed principally to springs rising in its bed. This is a point of
+which engineers now take notice, and M. Belgrand, the able officer
+charged with the improvement of the navigation of the Seine between
+Paris and Rouen, has devoted much attention to it."--BABINET, _Etudes et
+Lectures_, iii, p. 185.
+
+On page 232 of the volume just quoted, the same author observes: "In the
+lower part of its course, from the falls of the Oise, the Seine receives
+so few important affluents, that evaporation alone would suffice to
+exhaust all the water which passes under the bridges of Paris."
+
+This supposes a much greater amount of evaporation than has been usually
+computed, but I believe it is well settled that the Seine conveys to the
+sea much more water than is discharged into it by all its superficial
+branches.
+
+[393] Girard and Duchatelet maintain that the subterranean waters of
+Paris are absolutely stagnant. See their report on drainage by artesian
+wells, _Annales des Ponts et Chaussees_, 1833, 2me semestre, pp. 313,
+_et seqq._
+
+This opinion, if locally true, cannot be generally so, for it is
+inconsistent with the well-known fact that the very first eruption of
+water from a boring often brings up leaves and other objects which must
+have been carried into the underground reservoirs by currents.
+
+[394] _Physikalische Geographie_, p. 286. It does not appear whether
+this inference is Mariotte's or Wittwer's. I suppose it is a conclusion
+of the latter.
+
+[395] _Physical Geography of the Sea._ Tenth edition. London, 1861, Sec.
+274.
+
+[396] PARAMELLE, _Quellenkunde, mit einem Vorwort von_ B. COTTA, 1856.
+
+[397] _Etudes et Lectures_, vi, p. 118.
+
+[398] "The area of soil dried by draining is constantly increasing, and
+the water received by the surface from atmospheric precipitation is
+thereby partly conducted into new channels, and, in general, carried off
+more rapidly than before. Will not this fact exert an influence on the
+condition of many springs, whose basin of supply thus undergoes a
+partial or complete transformation? I am convinced that it will, and it
+is important to collect data for solving the question." BERNHARD COTTA,
+Preface to PARAMELLE, _Quellenkunde_ (German translation), pp. vii,
+viii. See _Appendix_, No. 54.
+
+[399] See the interesting observations of KRIEGK on this subject,
+_Schriften zur allgemeinen Erdkunde_, cap. iii, Sec. 6, and especially the
+passages in RITTER'S _Erdkunde_, vol. i, there referred to.
+
+Laurent, (_Memoires sur le Sahara Oriental_, pp. 8, 9), in speaking of a
+river at El-Faid, "which, like all those of the desert, is, most of the
+time, without water," observes, that many wells are dug in the bed of
+the river in the dry season, and that the subterranean current thus
+reached appears to extend itself laterally, at about the same level, at
+least a kilometre from the river, as water is found by digging to the
+depth of twelve or fifteen metres at a village situated at that distance
+from the bank.
+
+The most remarkable case of infiltration known to me by personal
+observation is the occurrence of fresh water in the beach sand on the
+eastern side of the Gulf of Akaba, the eastern arm of the Red Sea. If
+you dig a cavity in the beach near the sea level, it soon fills with
+water so fresh as not to be undrinkable, though the sea water two or
+three yards from it contains even more than the average quantity of
+salt. It cannot be maintained that this is sea water freshened by
+filtration through a few feet or inches of sand, for salt water cannot
+be deprived of its salt by that process. It can only come from the
+highlands of Arabia, and it would seem that there must exist some large
+reservoir in the interior to furnish a supply which, in spite of
+evaporation, holds out for months after the last rains of winter, and
+perhaps even through the year. I observed the fact in the month of June.
+
+The precipitation in the mountains that border the Red Sea is not known
+by pluviometric measurement, but the mass of debris brought down the
+ravines by the torrents proves that their volume must be large. The
+proportion of surface covered by sand and absorbent earth, in Arabia
+Petraea and the neighboring countries, is small, and the mountains drain
+themselves rapidly into the wadies or ravines where the torrents are
+formed; but the beds of earth and disintegrated rock at the bottom of
+the valleys are of so loose and porous texture, that a great quantity of
+water is absorbed in saturating them before a visible current is formed
+on their surface. In a heavy thunder storm, accompanied by a deluging
+rain, which I witnessed at Mount Sinai in the month of May, a large
+stream of water poured, in an almost continuous cascade, down the steep
+ravine north of the convent, by which travellers sometimes descend from
+the plateau between the two peaks, but after reaching the foot of the
+mountain, it flowed but a few yards before it was swallowed up in the
+sands.
+
+[400] It is conceivable that in large and shallow subterranean basins
+the superincumbent earth may rest upon the water and be partly supported
+by it. In such case the weight of the earth would be an additional, if
+not the sole, cause of the ascent of the water through the tubes of
+artesian wells. The elasticity of gases in the cavities may also aid in
+forcing up water.
+
+A French engineer, M. Mullot, invented a simple method of bringing to
+the surface water from any one of several successive accumulations at
+different depths, or of raising it, unmixed, from two or more of them at
+once. It consists in employing concentric tubes, one within the other,
+leaving a space for the rise of water between them, and reaching each to
+the sheet from which it is intended to draw.
+
+[401] Many more or less probable conjectures have been made on this
+subject, but thus far I am not aware that any of the apprehended results
+have been actually shown to have happened. In an article in the _Annales
+des Ponts et Chaussees_ for July and August, 1839, p. 131, it was
+suggested that the sinking of the piers of a bridge at Tours in France
+was occasioned by the abstraction of water from the earth by artesian
+wells, and the consequent withdrawal of the mechanical support it had
+previously given to the strata containing it. A reply to this article
+will be found in VIOLETT, _Theorie des Puits Artesiens_, p. 217.
+
+In some instances the water has rushed up with a force which seemed to
+threaten the inundation of the neighborhood, and even the washing away
+of much soil; but in those cases the partial exhaustion of the supply,
+or the relief of hydrostatic or elastic pressure, has generally produced
+a diminution of the flow in a short time, and I do not know that any
+serious evil has ever been occasioned in this way.
+
+[402] See a very interesting account of these wells, and of the workmen
+who clean them out when obstructed by sand brought up with the water, in
+Laurent's memoir on the artesian wells recently bored by the French
+Government in the Algerian desert, _Memoire sur le Sahara Oriental,
+etc._, pp. 19, _et seqq._ Some of the men remained under water from two
+minutes to two minutes and forty seconds. Several officers are quoted as
+having observed immersions of three minutes' duration, and M. Berbrugger
+alleges that he witnessed one of five minutes and fifty-five seconds.
+The shortest of these periods is longer than the best pearl diver can
+remain below the surface of salt water. The wells of the Sahara are from
+twenty to eighty metres deep.
+
+It has often been asserted that the ancient Egyptians were acquainted
+with the art of boring artesian wells. Parthey, describing the Little
+Oasis, mentions ruins of a Roman aqueduct, and observes: "It appears
+from the recent researches of Aim, a French engineer, that these
+aqueducts are connected with old artesian wells, the restoration of
+which would render it practicable to extend cultivation much beyond its
+present limits. This agrees with ancient testimony. It is asserted that
+the inhabitants of the oases sunk wells to the depth of 200, 300, and
+even 500 ells, from which affluent streams of water poured out. See
+OLYMPIODORUS in _Photii Bibl._, cod. 80, p. 61, l. 17, ed.
+Bekk."--PARTHEY, _Wanderungen_, ii, p. 528.
+
+In a paper entitled, _Note relative a l'execution d'un Puits Artesien en
+Egypte sous la XVIII dynastie_, presented to the Academie des
+Inscriptions et Belles Lettres, on the 12th of November, 1852, M.
+Lenormant endeavors to show that a hieroglyphic inscription found at
+Contrapscelcis proves the execution of a work of this sort in the Nubian
+desert, at the period indicated in the title to his paper. The
+interpretation of the inscription is a question for Egyptologists; but
+if wells were actually bored through the rock by the Egyptians after the
+Chinese or the European fashion, it is singular that among the numerous
+and minute representations of their industrial operations, painted or
+carved on the walls of their tombs, no trace of the processes employed
+for so remarkable and important a purpose should have been discovered.
+See _Appendix_, No. 56.
+
+It is certain that artesian wells have been common in China from a very
+remote antiquity, and the simple method used by the Chinese--where the
+borer is raised and let fall by a rope, instead of a rigid rod--has been
+lately been employed in Europe with advantage. Some of the Chinese wells
+are said to be 3,000 feet deep; that of Neusalzwerk in Silesia--the
+deepest in Europe--is 2,300. A well was bored at St. Louis, in Missouri,
+a few years ago, to supply a sugar refinery, to the depth of 2,199 feet.
+This was executed by a private firm in three years, at the expense of
+only $10,000. Another has since been bored at the State capitol at
+Columbus, Ohio, 2,500 feet deep, but without obtaining the desired
+supply of water.
+
+[403] "In the anticipation of our success at Oum-Thiour, every thing had
+been prepared to take advantage of this new source of wealth without a
+moment's delay. A division of the tribe of the Selmia, and their sheikh,
+Aissa ben Sha, laid the foundation of a village as soon as the water
+flowed, and planted twelve hundred date palms, renouncing their
+wandering life to attach themselves to the soil. In this arid spot, life
+had taken the place of solitude, and presented itself, with its smiling
+images, to the astonished traveller. Young girls were drawing water at
+the fountain; the flocks, the great dromedaries with their slow pace,
+the horses led by the halter, were moving to the watering trough; the
+hounds and the falcons enlivened the group of party-colored tents, and
+living voices and animated movement had succeeded to silence and
+desolation."--LAURENT, _Memoires sur le Sahara_, p. 85.
+
+[404] The variety of hues and tones in the local color of the desert is,
+I think, one of the phenomena which most surprise and interest a
+stranger to those regions. In England and the United States, rock is so
+generally covered with moss or earth, and earth with vegetation, that
+untravelled Englishmen and Americans are not very familiar with naked
+rock as a conspicuous element of landscape. Hence, in their conception
+of a bare cliff or precipice, they hardly ascribe definite color to it,
+but depict it to their imagination as wearing a neutral tint not
+assimilable to any of the hues with which nature tinges her atmospheric
+or paints her organic creations. There are certainly extensive desert
+ranges, chiefly limestone formations, where the surface is either white,
+or has weathered down to a dull uniformity of tone which can hardly be
+called color at all; and there are sand plains and drifting hills of
+wearisome monotony of tint. But the chemistry of the air, though it may
+tame the glitter of the limestone to a dusky gray, brings out the green
+and brown and purple of the igneous rocks, and the white and red and
+blue and violet and yellow of the sandstone. Many a cliff in Arabia
+Petraea is as manifold in color as the rainbow, and the veins are so
+variable in thickness and inclination, so contorted and involved in
+arrangement, as to bewilder the eye of the spectator like a disk of
+party-colored glass in rapid revolution.
+
+In the narrower wadies, the mirage is not common; but on broad expanses,
+as at many points between Cairo and Suez, and in Wadi el Araba, it mocks
+you with lakes and land-locked bays, studded with islands and fringed
+with trees, all painted with an illusory truth of representation
+absolutely indistinguishable from the reality. The checkered earth, too,
+is canopied with a heaven as variegated as itself. You see, high up in
+the sky, rosy clouds at noonday, colored probably by reflection from the
+ruddy mountains, while near the horizon float cumuli of a transparent
+ethereal blue, seemingly balled up out of the clear cerulean substance
+of the firmament, and detached from the heavenly vault, not by color or
+consistence, but solely by the light and shade of their prominences.
+
+[405] _[OE]uvres de Palissy, Des Eaux et Fontaines_, p. 157.
+
+[406] Id., p. 166. See _Appendix_, No. 57.
+
+[407] BABINET, _Etudes et Lectures sur les Sciences d'Observation_, ii,
+p. 225. Our author precedes his account of his method with a complaint
+which most men who indulge in thinking have occasion to repeat many
+times in the course of their lives. "I will explain to my readers the
+construction of artificial fountains according to the plan of the famous
+Bernard de Palissy, who, a hundred and fifty [three hundred] years ago,
+came and took away from me, a humble academician of the nineteenth
+century, this discovery which I had taken a great deal of pains to make.
+It is enough to discourage all invention when one finds plagiarists in
+the past as well as in the future!" (P. 224.)
+
+[408] M. G. DUMAS, _La Science des Fontaines_, 1857.
+
+[409] In the curiously variegated sandstone of Arabia Petraea--which is
+certainly a reaggregation of loose sand derived from particles of older
+rocks--the contiguous veins frequently differ very widely in color, but
+not sensibly in specific gravity or in texture; and the singular way in
+which they are now alternated, now confusedly intermixed, must be
+explained otherwise than by the weight of the respective grains which
+compose them. They seem, in fact, to have been let fall by water in
+violent ebullition or tumultuous mechanical agitation, or by a
+succession of sudden aquatic or aerial currents flowing in different
+directions and charged with differently colored matter.
+
+[410] _De Bodem van Nederland_, i, pp. 243, 246-377, _et seqq._ See also
+the arguments of Bremontier as to the origin of the dune sands of
+Gascony, _Annales des Ponts et Chaussees_, 1833, 1er semestre, pp. 158,
+161. Bremontier estimates the sand annually thrown up on that coast at
+five cubic toises and two feet to the running toise (ubi supra, p. 162),
+or rather more than two hundred and twenty cubic feet to the running
+foot. Laval, upon observations continued through seven years, found the
+quantity to be twenty-five metres per running metre, which is equal to
+two hundred and sixty-eight cubic feet to the running foot.--_Annales
+des Ponts et Chaussees_, 1842, 2me semestre, p. 229. These computations
+make the proportion of sand deposited on the coast of Gascony three or
+four times as great as that observed by Andresen on the shores of
+Jutland. Laval estimates the total quantity of sand annually thrown up
+on the coast of Gascony at 6,000,000 cubic metres, or more than
+7,800,000 cubic yards.
+
+[411] _De Bodem van Nederland_, i, p. 339.
+
+[412] The conditions favorable to the production of sand from
+disintegrated rock, by causes now in action, are perhaps nowhere more
+perfectly realized than in the Sinaitic Peninsula. The mountains are
+steep and lofty, unprotected by vegetation or even by a coating of
+earth, and the rocks which compose them are in a shattered and
+fragmentary condition. They are furrowed by deep and precipitous
+ravines, with beds sufficiently inclined for the rapid flow of water,
+and generally without basins in which the larger blocks of stone rolled
+by the torrents can be dropped and left in repose; there are severe
+frosts and much snow on the higher summits and ridges, and the winter
+rains are abundant and heavy. The mountains are principally of igneous
+formation, but many of the less elevated peaks are capped with
+sandstone, and on the eastern slope of the peninsula you may sometimes
+see, at a single glance, several lofty pyramids of granite, separated by
+considerable intervals, and all surmounted by horizontally stratified
+deposits of sandstone often only a few yards square, which correspond to
+each other in height, are evidently contemporaneous in origin, and were
+once connected in continuous beds. The degradation of the rock on which
+this formation rests is constantly bringing down masses of it, and
+mingling them with the basaltic, porphyritic, granitic, and calcareous
+fragments which the torrents carry down to the valleys, and, through
+them, in a state of greater or less disintegration, to the sea. The
+quantity of sand annually washed into the Red Sea by the larger torrents
+of the Lesser Peninsula, is probably at least equal to that contributed
+to the ocean by any streams draining basins of no greater extent.
+Absolutely considered, then, the mass may be said to be large, but it is
+apparently very small as compared with the sand thrown up by the German
+Ocean and the Atlantic on the coasts of Denmark and of France. There
+are, indeed, in Arabia Petraea, many torrents with very short courses,
+for the sea waves in many parts of the peninsular coast wash the base of
+the mountains. In these cases, the debris of the rocks do not reach the
+sea in a sufficiently comminuted condition to be entitled to the
+appellation of sand, or even in the form of well-rounded pebbles. The
+fragments retain their angular shape, and, at some points on the coast,
+they become cemented together by lime or other binding substances held
+in solution or mechanical suspension in the sea water, and are so
+rapidly converted into a singularly heterogeneous conglomerate, that one
+deposit seems to be consolidated into a breccia before the next winter's
+torrents cover it with another.
+
+In the northern part of the peninsula there are extensive deposits of
+sand intermingled with agate pebbles and petrified wood, but these are
+evidently neither derived from the Sinaitic group, nor products of local
+causes known to be now in action.
+
+I may here notice the often repeated but mistaken assertion, that the
+petrified wood of the Western Arabian desert consists wholly of the
+stems of palms, or at least of endogenous vegetables. This is an error.
+I have myself picked up in that desert, within the space of a very few
+square yards, fragments both of fossil palms, and of at least two
+petrified trees distinctly marked as of exogenous growth both by annular
+structure and by knots. In ligneous character, one of these almost
+precisely resembles the grain of the extant beech, and this specimen was
+wormeaten before it was converted into silex.
+
+[413] BOeTTGER, _Das Mittelmeer_, p. 128.
+
+[414] The testimony of divers and of other observers on this point is
+conflicting, as might be expected from the infinite variety of
+conditions by which the movement of water is affected. It is generally
+believed that the action of the wind upon the water is not perceptible
+at greater depths than from fifteen feet in ordinary, to eighty or
+ninety in extreme cases; but these estimates are probably very
+considerably below the truth. Andresen quotes Bremontier as stating that
+the movement of the waves sometimes extends to the depth of five hundred
+feet, and he adds that others think it may reach to six or even seven
+hundred feet below the surface.--ANDRESEN, _Om Klitformationen_, p. 20.
+
+Many physicists now suppose that the undulations of great bodies of
+water reach even deeper. But a movement of undulation is not necessarily
+a movement of translation, and besides, there is very frequently an
+undertow, which tends to carry suspended bodies out to sea as powerfully
+as the superficial waves to throw them on shore. Sandbanks sometimes
+recede from the coast, instead of rolling toward it. Reclus informs us
+that the Mauvaise, a sandbank near the Point de Grave, on the Atlantic
+coast of France, has moved five miles to the west in less than a
+century.--_Revue des Deux Mondes_, for December, 1862, p. 905.
+
+The action of currents may, in some cases, have been confounded with
+that of the waves. Sea currents, strong enough, possibly, to transport
+sand for some distance, flow far below the surface in parts of the open
+ocean, and in narrow straits they have great force and velocity. The
+divers employed at Constantinople in 1853 found in the Bosphorus, at the
+depth of twenty-five fathoms and at a point much exposed to the wash
+from Galata and Pera, a number of bronze guns supposed to have belonged
+to a ship of war blown up about a hundred and fifty years before. These
+guns were not covered by sand or slime, though a crust of earthy matter,
+an inch in thickness, adhered to their upper surfaces, and the bottom of
+the strait appeared to be wholly free from sediment. The current was so
+powerful at this depth that the divers were hardly able to stand, and a
+keg of nails, purposely dropped into the water, in order that its
+movements might serve as a guide in the search for a bag of coin
+accidentally lost overboard from a ship in the harbor, was rolled by the
+stream several hundred yards before it stopped.
+
+[415] Few seas have thrown up so much sand as the shallow German Ocean;
+but there is some reason to think that the amount of this material now
+cast upon its northern shores is less than at some former periods,
+though no extensive series of observations on this subject has been
+recorded. On the Spit of Agger, at the present outlet of the Liimfjord,
+Andresen found the quantity during ten years, on a beach about five
+hundred and seventy feet broad, equal to an annual deposit of an inch
+and a half over the whole surface.--_Om Klitformationen_, p. 56.
+
+This gives seventy-one and a quarter cubic feet to the running foot--a
+quantity certainly much smaller than that cast up by the same sea on the
+shores of the Dano-German duchies and of Holland, and, as we have seen,
+scarcely one fourth of that deposited by the Atlantic on the coast of
+Gascony. See _ante_, p. 453, note.
+
+[416] Sand heaps, three and even six hundred feet high, are indeed
+formed by the wind, but this is effected by driving the particles up an
+inclined plane, not by lifting them. Bremontier, speaking of the sand
+hills on the western coast of France, says: "The particles of sand
+composing them are not large enough to resist wind of a certain force,
+nor small enough to be taken up by it, like dust; they only roll along
+the surface from which they are detached, and, though moving with great
+velocity, they rarely rise to a greater height than three or four
+inches."--_Memoire sur les Dunes, Annales des Ponts et Chaussees_, 1833,
+1er semestre, p. 148.
+
+Andresen says that a wind, having a velocity of forty feet per second,
+is strong enough to raise particles of sand as high as the face and eyes
+of a man, but that, in general, it rolls along the ground, and is
+scarcely ever thrown more than to the height of a couple of yards from
+the surface. Even in these cases, it is carried forward by a hopping,
+not a continuous, motion; for a very narrow sheet or channel of water
+stops the drift entirely, all the sand dropping into it until it is
+filled up.
+
+The character of the motion of sand drifts is well illustrated by an
+interesting fact not much noticed hitherto by travellers in the East. In
+situations where the sand is driven through depressions in rock beds, or
+over deposits of silicious pebbles, the surface of the stone is worn and
+smoothed much more effectually than it could be by running water, and
+you may pick up, in such localities, rounded, irregularly broken
+fragments of agate, which have received from the attrition of the sand
+as fine a polish as could be given them by the wheel of the lapidary.
+
+Very interesting observations on the polishing of hard stones by
+drifting sand will be found in the Geological Report of William P.
+Blake: _Pacific Railroad Report_, vol. v, pp. 92, 230, 231. The same
+geologist observes, p. 242, that the sand of the Colorado desert does
+not rise high in the air, but bounds along on the surface or only a few
+inches above it.
+
+[417] Wilkinson says that, in much experience in the most sandy parts of
+the Libyan desert, and much inquiry of the best native sources, he never
+saw or heard of any instance of danger to man or beast from the mere
+accumulation of sand transported by the wind. Chesney's observations in
+Arabia, and the testimony of the Bedouins he consulted, are to the same
+purpose. The dangers of the simoom are of a different character, though
+they are certainly aggravated by the blinding effects of the light
+particles of dust and sand borne along by it, and by that of the
+inhalation of them upon the respiration.
+
+[418] In the narrow valley of the Nile, bounded as it is, above the
+Delta, by high cliffs, all air currents from the northern quarter become
+north winds, though, of course varying in partial direction, in
+conformity with the sinuosities of the valley. Upon the desert plateau
+they incline westward, and have already borne into the valley the sands
+of the eastern banks, and driven those of the western quite out of the
+Egyptian portion of the Nile basin.
+
+[419] "The North African desert falls into two divisions: the Sahel, or
+western, and the Sahar, or eastern. The sands of the Sahar were, at a
+remote period, drifted to the west. In the Sahel, the prevailing east
+winds drive the sand-ocean with a progressive westward motion. The
+eastern half of the desert is swept clean."--NAUMANN, _Geognosie_, ii,
+p. 1173.
+
+[420] In parts of the Algerian desert, some efforts are made to retard
+the advance of sand dunes which threaten to overwhelm villages. "At
+Debila," says Laurent, "the lower parts of the lofty dunes are planted
+with palms, * * * but they are constantly menaced with burial by the
+sands. The only remedy employed by the natives consists in little dry
+walls of crystallized gypsum, built on the crests of the dunes, together
+with hedges of dead palm leaves. These defensive measures are aided by
+incessant labor; for every day the people take up in baskets the sand
+blown over to them the night before and carry it back to the other side
+of the dune."--_Memoires sur le Sahara_, p. 14.
+
+[421] Organic constituents, such as comminuted shells, and silicious and
+calcareous exuviae of infusorial animals and plants, are sometimes found
+mingled in considerable quantities with mineral sands. These are usually
+the remains of aquatic vegetables or animals, but not uniformly so, for
+the microscopic organisms, whose flinty cases enter so largely into the
+sandbeds of the Mark of Brandenburg, are still living and prolific in
+the dry earth. See WITTWER, _Physikalische Geographie_, p. 142.
+
+The desert on both sides of the Nile is inhabited by a land snail, and
+thousands of its shells are swept along and finally buried in the drifts
+by every wind. Every handful of the sand contains fragments of them.
+FORCHHAMMER, in LEONHARD Und BRONN's _Jahrbuch_, 1841, p. 8, says of the
+sand hills of the Danish coast: "It is not rare to find, high in the
+knolls, marine shells, and especially those of the oyster. They are due
+to the oyster eater [_Haemalopus ostralegus_], which carries his prey to
+the top of the dunes to devour it." See also STARING, _De Bodem van_, N.
+I. p. 321.
+
+[422] There are various reasons why the formation of dunes is confined
+to low shores, and this law is so universal, that when bluffs are
+surmounted by them, there is always cause to suspect upheaval, or the
+removal of a sloping beach in front of the bluff, after the dunes were
+formed. Bold shores are usually without a sufficient beach for the
+accumulation of large deposits; they are commonly washed by a sea too
+deep to bring up sand from its bottom; their abrupt elevation, even if
+moderate in amount, would still be too great to allow ordinary winds to
+lift the sand above them; and their influence in deadening the wind
+which blows toward them would even more effectually prevent the raising
+of sand from the beach at their foot.
+
+Forchhammer, describing the coast of Jutland, says that, in high winds,
+"one can hardly stand upon the dunes, except when they are near the
+water line and have been cut down perpendicularly by the waves. Then the
+wind is little or not at all felt--a fact of experience very common on
+our coasts, observed on all the steep shore bluffs of two hundred feet
+in height, and, in the Faroe Islands, on precipices two thousand feet
+high. In heavy gales in those islands, the cattle fly to the very edge
+of the cliffs for shelter, and frequently fall over. The wind, impinging
+against the vertical wall, creates an ascending current which shoots
+somewhat past the crest of the rock, and thus the observer or the animal
+is protected against the tempest by a barrier of air."--LEONHARD und
+BRONN, _Jahrbuch_, 1841, p. 3.
+
+The calming, or rather diversion, of the wind by cliffs extends to a
+considerable distance in front of them, and no wind would have
+sufficient force to raise the sand vertically, parallel to the face of a
+bluff, even to the height of twenty feet.
+
+It is very commonly believed that it is impossible to grow forest trees
+on sea-shore bluffs, or points much exposed to strong winds. The
+observations just cited tend to show that it would not be difficult to
+protect trees from the mechanical effect of the wind, by screens much
+lower than the height to which they are expected to grow. Recent
+experiments confirm this, and it is found that, though the outer row or
+rows may suffer from the wind, every tree shelters a taller one behind
+it. Extensive groves have thus been formed in situations where an
+isolated tree would not grow at all.
+
+Piper, in his _Trees of America_, p. 19, gives an interesting account of
+Mr. Tudor's success in planting trees on the bleak and barren shore of
+Nahant. "Mr. Tudor," observes he, "has planted more than ten thousand
+trees at Nahant, and, by the results of his experiments, has fully
+demonstrated that trees, properly cared for in the beginning, may be
+made to grow up to the very bounds of the ocean, exposed to the biting
+of the wind and the spray of the sea. The only shelter they require is,
+at first, some interruption to break the current of the wind, such as
+fences, houses, or other trees."
+
+[423] The careful observations of Colonel J. D. Graham, of the United
+States Army, show a tide of about three inches in Lake Michigan. See "A
+Lunar Tidal Wave in the North American Lakes," demonstrated by
+Lieut.-Colonel J. D. Graham, in the fourteenth volume of the
+_Proceedings of the American Association for the Advancement of
+Science_.
+
+[424] STARING, _De Bodem van Nederland_, i, p. 327, note.
+
+[425] The principal special works and essays on this subject known to me
+are:
+
+BREMONTIER, _Memoire sur les Dunes, etc._, 1790, reprinted in _Annales
+des Ponts et Chaussees_, 1833, 1er semestre, pp. 145-186.
+
+_Rapport sur les differents Memoires de M. Bremontier_, par LAUMONT et
+autres, 1806, same volume, pp. 192, 224.
+
+LEFORT, _Notice sur les Travaux de Fixation des Dunes, Annales des Ponts
+et Chaussees_, 1831, 2me semestre, pp. 320-332.
+
+FORCHHAMMER, _Geognostische Studien am Meeres Ufer_, in LEONHARD und
+BRONN, _Jahrbuch, etc._, 1841, pp. 1, 38.
+
+J. G. KOHL, _Die Inseln und Marschen der Herzogthuemer Schleswig und
+Holstein_, 1846, vol. ii, pp. 112-162, 193-204.
+
+LAVAL, _Memoire sur les Dunes du Golfe de Gascogne, Annales des Ponts et
+Chaussees_, 1847, 2me semestre, pp. 218-268.
+
+G. C. A. KRAUSE, _Der Duenenbau auf den Ostsee-Kuesten West-Preussens_,
+1850, 1 vol. 8vo.
+
+W. C. H. STARING, _De Bodem van Nederland_, 1856, vol. i, pp. 310-341,
+and 424-431.
+
+Same author, _Voormaals en Thans_, 1858, pages cited.
+
+C. C. ANDRESEN, _Om Klitformationen og Klittens Behandling og
+Bestyrelse_, 1861, 1 vol. 8vo, x, 392 pp., much the most complete
+treatise on the subject.
+
+ANDRESEN cites, upon the origin of the dunes: HULL, _Over den Oorsprong
+en de Geschiedenis der Hollandsche Duinen_, 1838, and GROSS's
+_Veiledning ved Behandlingen af Sandflugtstraekningerne_, 1847; and upon
+the improvement of sand plains by planting, PANNEWITZ, _Anleitung zum
+Anbau der Sandflaechen_, 1832. I am not acquainted with either of the
+latter two works but I have consulted with advantage, on this subject,
+DELAMARRE, _Historique de la Creation d'une Richesse millionaire par la
+culture des Pins_, 1827; BOITEL, _Mise en valeur des terres pauvres par
+le Pin maritime_, 1857; and BRINCKEN, _Ansichten ueber die Bewaldung der
+Steppen des Europaeischen Russlands_, 1854.
+
+[426] "Dunes are always full of water, from the action of capillary
+attraction. Upon the summits, one seldom needs to dig more than a foot
+to find the sand moist, and in the depressions, fresh water is met with
+near the surface."--FORCHHAMMER, in LEONHARD und BRONN, for 1841, p. 5,
+note.
+
+On the other hand, Andresen, who has very carefully investigated this as
+well as all other dune phenomena, maintains that the humidity of the
+sand ridges cannot be derived from capillary attraction. He found by
+experiment that drift sand was not moistened to a greater height than
+eight and a half inches, after standing a whole night in water. He
+states the minimum of water contained by the sand of the dunes, one foot
+below the surface, after a long drought, at two per cent., the maximum,
+after a rainy month, at four per cent. At greater depths the quantity is
+larger. The hygroscopicity of the sand of the coast of Jutland he found
+to be thirty-three per cent. by measure, or 21.5 by weight. The annual
+precipitation on that coast is twenty-seven inches, and, as the
+evaporation is about the same, he argues that rain water does not
+penetrate far beneath the surface of the dunes, and concludes that their
+humidity can be explained only by evaporation from below.--_Om
+Klitformationen_, pp. 106-110.
+
+In the dunes of Algeria, water is so abundant that wells are constantly
+dug in them at high points on their surface. They are sunk to the depth
+of three or four metres only, and the water rises to the height of a
+metre in them.--LAURENT, _Memoire sur le Sahara_, pp. 11, 12, 13.
+
+The same writer observes (p. 14) that the hollows in the dunes are
+planted with palms which find moisture enough a little below the
+surface. It would hence seem that the proposal to fix the dunes which
+are supposed to threaten the Suez Canal, by planting the maritime pine
+and other trees upon them, is not altogether so absurd as it is thought
+to be by some of those disinterested philanthropists of other nations
+who are distressed with fears that French capitalists will lose the
+money they have invested in that great undertaking.
+
+Ponds of water are often found in the depressions between the sand hills
+of the dune chains in the North American desert.
+
+[427] According to the French authorities, the dunes of France are not
+always composed of quartzose sand. "The dune sands" of different
+characters, says Bremontier, "partake of the nature of the different
+materials which compose them. At certain points on the coast of Normandy
+they are found to be purely calcareous; they are of mixed composition on
+the shores of Brittany and Saintonge, and generally quartzose between
+the mouth of the Gironde and that of the Adour."--_Memoire sur les
+Dunes, Annales des Ponts et Chaussees_, t. vii, 1833, 1er semestre, p.
+146.
+
+In the dunes of Long Island and of Jutland, there are considerable veins
+composed almost wholly of garnet. For a very full examination of the
+mechanical and chemical composition of the dune sands of Jutland, see
+ANDRESEN, _Om Klitformationen_, p. 110.
+
+[428] _De Bodem van Nederland_, i, p. 323.
+
+[429] J. G. KOHL, _Die Inseln und Marschen der Herzogthuemer Schleswig
+und Holstein_, ii, p. 200.
+
+[430] STARING, _De Bodem van Nederland_, i, p. 317. See also, BERGSOeE,
+_Reventov's Virksomhed_, ii, p. 11.
+
+"In the sand-hill ponds mentioned in the text, there is a vigorous
+growth of bog plants accompanied with the formation of peat, which goes
+on regularly as long as the dune sand does not drift. But if the surface
+of the dunes is broken, the sand blows into the ponds, covers the peat,
+and puts an end to its formation. When, in the course of time, marine
+currents cut away the coast, the dunes move landward and fill up the
+ponds, and thus are formed the remarkable strata of fossile peat called
+Martoerv, which appears to be unknown to the geologists of other parts of
+Europe."--FORCHHAMMER, in LEONHARD und BRONN, 1841, p. 13.
+
+[431] The lower strata must be older than the superficial layers, and
+the particles which compose them may in time become more disintegrated,
+and therefore finer than those deposited later and above them.
+
+[432] "On the west coast of Africa the dunes are drifting seawards, and
+always receiving new accessions from the Sahara. They are constantly
+advancing out into the sea." See _ante_, p. 16, note.--NAUMANN,
+_Geognosie_, ii, p. 1172. See _Appendix_, No. 58.
+
+[433] Forchhammer, after pointing out the coincidence between the
+inclined stratification of dunes and the structure of ancient tilted
+rocks, says: "But I am not able to point out a sandstone formation
+corresponding to the dunes. Probably most ancient dunes have been
+destroyed by submersion before the loose sand became cemented to solid
+stone, but we may suppose that circumstances have existed somewhere
+which have preserved the characteristics of this formation."--LEONHARD
+und BRONN, 1841, p. 8, 9.
+
+Such formations, however, certainly exist. I find from Laurent (_Memoire
+sur le Sahara, etc._, p. 12), that in the Algerian desert there exist
+"sandstone formations" not only "corresponding to the dunes," but
+actually consolidated within them. "A place called El-Mouia-Tadjer
+presents a repetition of what we saw at El-Baya; one of the funnels
+formed in the middle of the dunes contains wells from two metres to two
+and a half in depth, dug in a sand which pressure, and probably the
+presence of certain salts, have cemented so as to form true sandstone,
+soft indeed, but which does not yield except to the pickaxe. These
+sandstones exhibit an inclination which seems to be the effect of wind;
+for they conform to the direction of the sands which roll down a scarp
+occasioned by the primitive obstacle." See _Appendix_, No. 59.
+
+The dunes near the mouth of the Nile, the lower sands of which have been
+cemented together by the infiltration of Nile water, would probably show
+a similar stratification in the sandstone which now forms their base.
+
+[434] Forchhammer ascribes the resemblance between the furrowing of the
+dune sands and the beach ripples, not to the similarity of the effect of
+wind and water upon sand, but wholly to the action of the former fluid;
+in the first instance, directly, in the latter, through the water. "The
+wind ripples on the surface of the dunes precisely resemble the water
+ripples of sand flats occasionally overflowed by the sea; and with the
+closest scrutiny, I have never been able to detect the slightest
+difference between them. This is easily explained by the fact, that the
+water ripples are produced by the action of light wind on the water
+which only transmits the air waves to the sand."--LEONHARD und BRONN,
+1841, pp. 7, 8.
+
+[435] American observers do not agree in their descriptions of the form
+and character of the sand grains which compose the interior dunes of the
+North American desert. C. C. Parry, geologist to the Mexican Boundary
+Commission, in describing the dunes near the station at a spring
+thirty-two miles west from the Rio Grande at El Paso, says: "The
+separate grains of the sand composing the sand hills are seen under a
+lens to be angular, and not rounded, as would be the case in regular
+beach deposits."--_U. S. Mexican Boundary Survey, Report of_, vol. i,
+_Geological Report of C. C. Parry_, p. 10.
+
+In the general description of the country traversed, same volume, p. 47,
+Colonel Emory says that on an "examination of the sand with a microscope
+of sufficient power," the grains are seen to be angular, not rounded by
+rolling in water.
+
+On the other hand, Blake, in _Geological Report, Pacific Railroad Rep._,
+vol. v, p. 119, observes that the grains of the dune sand, consisting of
+quartz, chalcedony, carnelian, agate, rose quartz, and probably
+chrysolite, were much rounded; and on page 241, he says that many of the
+sand grains of the Colorado desert are perfect spheres.
+
+On page 20 of a report in vol. ii of the _Pacific Railroad Report_, by
+the same observer, it is said that an examination of dune sands brought
+from the Llano Estacado by Captain Pope, showed the grains to be "much
+rounded by attrition."
+
+The sands described by Mr. Parry and Colonel Emory are not from the same
+localities as those examined by Mr. Blake, and the difference in their
+character may denote a difference of origin or of age.
+
+[436] LAURENT (_Memoire sur le Sahara_, pp. 11, 12, and elsewhere)
+speaks of a funnel-shaped depression at a high point in the dunes, as a
+characteristic feature of the sand hills of the Algerian desert. This
+seems to be an approximation to the crescent form noticed by Meyen and
+Poeppig in the inland dunes of Peru.
+
+[437] _Travels in Peru_, New York, 1848, chap. ix.
+
+[438] Notwithstanding the general tendency of isolated coast dunes and
+of the peaks of the sand ridges to assume a conical form, Andresen
+states that the hills of the inner or landward rows are sometimes
+_bow-shaped_, and sometimes undulating in outline.--_Om
+Klitformationen_, p. 84. He says further that: "Before an obstruction,
+two or three feet high and considerably longer, lying perpendicularly to
+the direction of the wind, the sand is deposited with a windward angle
+of from 6 deg. to 12 deg., and the bank presents a concave face to the wind,
+while, behind the obstruction, the outline is convex;" and he lays it
+down as a general rule, that a slope, _from_ which sand is blown, is
+left with a concavity of about one inch of depth to four feet of
+distance; a slope, _upon_ which sand is dropped by the wind, is convex.
+It appears from Andresen's figures, however, that the concavity and
+convexity referred to, apply, not to the _horizontal longitudinal_
+section of the sand bank, as his language unexplained by the drawings
+might be supposed to mean, but to the _vertical cross-section_, and
+hence the dunes he describes, with the exception above noted, do not
+correspond to those of the American deserts.--_Om Klitformationen_, p.
+86.
+
+The dunes of Gascony, which sometimes exceed three hundred feet in
+height, present the same concavity and convexity of _vertical_
+cross-section. The slopes of these dunes are much steeper than those of
+the Netherlands and the Danish coast; for while all observers agree in
+assigning to the seaward and landward faces of those latter,
+respectively, angles of from 5 deg. to 12 deg., and 30 deg. with the horizon, the
+corresponding faces of the dunes of Gascony present angles of from 10 deg.
+to 25 deg., and 50 deg. to 60 deg..--LAVAL, _Memoire sur les Dunes de Gascogne,
+Annales des Ponts et Chaussees_, 1847, 2me semestre.
+
+[439] Krause, speaking of the dunes on the coast of Prussia, says:
+"Their origin belongs to three different periods, in which important
+changes in the relative level of sea and land have unquestionably taken
+place. * * * Except in the deep depressions between them, the dunes are
+everywhere sprinkled, to a considerable height, with brown oxydulated
+iron, which has penetrated into the sand to the depth of from three to
+eighteen inches, and colored it red. * * * Above the iron is a stratum
+of sand differing in composition from ordinary sea sand, and on this,
+growing woods are always found. * * * The gradually accumulated forest
+soil occurs in beds of from one to three feet thick, and changes,
+proceeding upward, from gray sand to black humus." Even on the third or
+seaward range, the sand grasses appear and thrive luxuriantly, at least
+on the west coast, though. Krause doubts whether the dunes of the east
+coast were ever thus protected.--_Der Duenenbau_, pp. 8, 11.
+
+[440] LAVAL, _Memoire sur les Dunes de Gascogne, Annales des Ponts et
+Chaussees_, 1847, 2me semestre, p. 231. The same opinion had been
+expressed by BREMONTIER, _Annales des Ponts et Chaussees_, 1833, 1er
+semestre, p. 185.
+
+[441] "In the Middle Ages," says Willibald Alexis, as quoted by Mueller,
+_Das Buch der Pflanzenwelt_ i, p. 16, "the Nehrung was extending itself
+further, and the narrow opening near Lochstadt had filled itself up with
+sand. A great pine forest bound with its roots the dune sand and the
+heath uninterruptedly from Danzig to Pillau. King Frederick William I
+was once in want of money. A certain Herr von Korff promised to procure
+it for him, without loan or taxes, if he could be allowed to remove
+something quite useless. He thinned out the forests of Prussia, which
+then, indeed, possessed little pecuniary value; but he felled the entire
+woods of the Frische Nehrung, so far as they lay within the Prussian
+territory. The financial operation was a success. The king had money,
+but in the elementary operation which resulted from it, the state
+received irreparable injury. The sea winds rush over the bared hills;
+the Frische Haff is half-choked with sand; the channel between Elbing,
+the sea, and Koenigsberg is endangered, and the fisheries in the Haff
+injured. The operation of Herr von Korff brought the king 200,000
+thalers. The state would now willingly expend millions to restore the
+forests again."
+
+[442] STARING, _Voormaals en Thans_, p. 231. Had the dunes of the
+Netherlandish and French coasts, at the period of the Roman invasion,
+resembled the moving sand hills of the present day, it is inconceivable
+that they could have escaped the notice of so acute a physical
+geographer as Strabo; and the absolute silence of Caesar, Ptolemy, and
+the encyclopaedic Pliny, respecting them, would be not less inexplicable.
+
+The Old Northern language, the ancient tongue of Denmark, though rich in
+terms descriptive of natural scenery, had no name for dune, nor do I
+think the sand hills of the coast are anywhere noticed in Icelandic
+literature. The modern Icelanders, in treating of the dunes of Jutland,
+call them _klettr_, hill, cliff, and the Danish _klit_ is from that
+source. The word Duene is also of recent introduction into German. Had
+the dunes been distinguished from other hillocks, in ancient times, by
+so remarkable a feature as the propensity to drift, they would certainly
+have acquired a specific name in both Old Northern and German. So long
+as they were wooded knolls, they needed no peculiar name; when they
+became formidable, from the destruction of the woods which confined
+them, they acquired a designation.
+
+[443] The sands of Cape Cod were partially, if not completely, covered
+with vegetation by nature. Dr. Dwight, describing the dunes as they were
+in 1800, says: "Some of them are covered with beach grass; some fringed
+with whortleberry bushes; and some tufted with a small and singular
+growth of oaks. * * * The parts of this barrier, which are covered with
+whortleberry bushes and with oaks, have been either not at all, or very
+little blown. The oaks, particularly, appear to be the continuation of
+the forests originally formed on this spot. * * * They wore all the
+marks of extreme age; were, in some instances, already decayed, and in
+others decaying; were hoary with moss, and were deformed by branches,
+broken and wasted, not by violence, but by time."--_Travels_, iii, p.
+91.
+
+[444] Bergsoee (_Reventlovs Virksomhed_, ii, 3) states that the dunes on
+the west coast of Jutland were stationary before the destruction of the
+forests to the east of them. The felling of the tall trees removed the
+resistance to the lower currents of the westerly winds, and the sands
+have since buried a great extent of fertile soil. See also same work,
+ii, p. 124.
+
+[445] "We must, therefore, not be surprised to see the people here deal
+as gingerly with their dunes, as if treading among eggs. He who is lucky
+enough to own a molehill of dune pets it affectionately, and spends his
+substance in cherishing and fattening it. That fair, fertile, rich
+province, the peninsula of Eiderstaedt in the south of Friesland, has, on
+the point toward the sea, only a tiny row of dunes, some six miles long
+or so; but the people talk of their fringe of sand hills as if it were a
+border set with pearls. They look upon it as their best defence against
+Neptune. They have connected it with their system of dikes, and for
+years have kept sentries posted to protect it against wanton
+injury."--J. G. KOHL, _Die Inseln u. Marschen Schleswig-Holsteins_, ii,
+p. 115.
+
+[446] Sand banks sometimes connect themselves with the coast at both
+ends, and thus cut off a portion of the sea. In this case, as well as
+when salt water is enclosed by sea dikes, the water thus separated from
+the ocean gradually becomes fresh, or at least brackish. The Haffs, or
+large expanses of fresh water in Eastern Prussia--which are divided from
+the Baltic by narrow sand banks called Nehrungen, or, at sheltered
+points of the coast, by fluviatile deposits called Werders--all have one
+or more open passages, through which the water of the rivers that supply
+them at last finds its way to the sea.
+
+[447] ANDRESEN, _Om Klitformationen_, pp. 68-72.
+
+[448] Id., pp. 231, 232. Andresen's work, though printed in 1861, was
+finished in 1859. Lyell (_Antiquity of Man_, 1863, p. 14) says: "Even in
+the course of the present century, the salt waters have made one
+eruption into the Baltic by the Liimfjord, although they have been now
+again excluded."
+
+[449] FORCHHAMMER, _Geognostische Studien am Meeres-Ufer_. LEONHARD und
+BRONN, _Jahrbuch_, 1841, pp. 11, 13.
+
+[450] ANDRESEN, _Om Klitformationen_, pp. 68, 72.
+
+[451] _Voormaals en Thans_, pp. 126, 170.
+
+[452] See a very interesting article entitled "Le Littoral de la
+France," by ELISEE RECLUS, in the _Revue des Deux Mondes_, for December,
+1862, pp. 901, 936.
+
+[453] _De Bodem van Nederland_, i, p. 425. See _Appendix_, No. 60.
+
+[454] The movement of the dunes has been hardly less destructive on the
+north side of the Gironde. Sea the valuable article of ELISEE RECLUS
+already referred to, in the _Revue des Deux Mondes_, for December, 1862,
+entitled "Le Littoral de la France."
+
+[455] LAVAL, _Memoire sur les Dunes du Golfe de Gascogne, Annales des
+Ponts et Chaussees_, 1847, p. 223. The author adds, as a curious and
+unexplained fact, that some of these pools, though evidently not
+original formations but mere accumulations of water dammed up by the
+dunes, have, along their western shore, near the base of the sand hills,
+a depth of more than one hundred and thirty feet, and hence their
+bottoms are not less than eighty feet below the level of the lowest
+tides. Their western banks descend steeply, conforming nearly to the
+slope of the dunes, while on the northeast and south the inclination of
+their beds is very gradual. The greatest depth of these pools
+corresponds to that of the sea ten miles from the shore. Is it possible
+that the weight of the sands has pressed together the soil on which they
+rest, and thus occasioned a subsidence of the surface extending beyond
+their base? See _Appendix_, No. 61.
+
+[456] ANDRESEN, _Om Klitformationem_, pp. 56, 79, 82.
+
+[457] STARING, _De Bodem van Nederland_, i, pp. 329-331. Id., _Voormaals
+en Thans_, p. 163. ANDRESEN, _Om Klitformationen_, pp. 280, 295.
+
+The creation of new dunes, by the processes mentioned in the text, seems
+to be much older in Europe than the adoption of measures for securing
+them by planting. Dr. Dwight mentions a case in Massachusetts, where a
+beach was restored, and new dunes formed, by planting beach grass.
+"Within the memory of my informant, the sea broke over the beach which
+connects Truro with Province Town, and swept the body of it away for
+some distance. The beach grass was immediately planted on the spot; in
+consequence of which the beach was again raised to a sufficient height,
+and in various places into hills."--_Dwight's Travels_, iii, p. 93.
+
+[458] STARING, i, pp. 310, 332.
+
+[459] There is some confusion in the popular use of these names, and in
+the scientific designations of sand plants, and they are possibly
+applied to different plants in different places. Some writers style the
+gourbet _Calamagrostis arenaria_, and distinguish it from the Danish
+Klittetag or Hjelme.
+
+[460] Bread, not indeed very palatable, has been made of the seeds of
+the arundo, but the quantity which can be gathered is not sufficient to
+form an important economical resource.----ANDRESEN, _Om
+Klitformationen_, p. 160.
+
+[461] BERGSOeE, _Reventlovs Virksomhed_, ii, p. 4.
+
+[462] Measures were taken for the protection of the dunes of Cape Cod,
+in Massachusetts, during the colonial period, though I believe they are
+now substantially abandoned. A hundred years ago, before the valley of
+the Mississippi, or even the rich plains of Central and Western New
+York, were opened to the white settler, the value of land was relatively
+much greater in New England than it is at present, and consequently some
+rural improvements were then worth making, which would not now yield
+sufficient returns to tempt the investment of capital. The money and the
+time required to subdue and render productive twenty acres of sea sand
+on Cape Cod, would buy a "section" and rear a family in Illinois. The
+son of the Pilgrims, therefore, abandons the sand hills, and seeks a
+better fortune on the fertile prairies of the West.
+
+Dr. Dwight, who visited Cape Cod in the year 1800, after describing the
+"beach grass, a vegetable bearing a general resemblance to sedge, but of
+a light bluish-green, and of a coarse appearance," which "flourishes
+with a strong and rapid vegetation on the sands," observes that he
+received "from a Mr. Collins, formerly of Truro, the following
+information:" "When he lived at Truro, the inhabitants were, under the
+authority of law, regularly warned in the month of April, yearly, to
+plant beach grass, as, in other towns of New England, they are warned to
+repair highways. It was required by the laws of the State, and under the
+proper penalties for disobedience; being as regular a public tax as any
+other. The people, therefore, generally attended and performed the
+labor. The grass was dug in bunches, as it naturally grows; and each
+bunch divided into a number of smaller ones. These were set out in the
+sand at distances of three feet. After one row was set, others were
+placed behind it in such a manner as to shut up the interstices; or, as
+a carpenter would say, so as to break the joints. * * * When it is once
+set, it grows and spreads with rapidity. * * * The seeds are so heavy
+that they bend down the heads of the grass; and when ripe, drop directly
+down by its side, where they immediately vegetate. Thus in a short time
+the ground is covered.
+
+"Where this covering is found, none of the sand is blown. On the
+contrary, it is accumulated and raised continually as snow gathers and
+rises among bushes, or branches of trees cut and spread upon the earth.
+Nor does the grass merely defend the surface on which it is planted; but
+rises, as that rises by new accumulations; and always overtops the sand,
+however high that may be raised by the wind."--_Dwight's Travels in New
+England and New York_, ii, p. 92, 93.
+
+This information was received in 1800, and it relates to a former state
+of things, probably more than twenty years previous, and earlier than
+1779, when the Government of Denmark first seriously attempted the
+conquest of the dunes.
+
+The depasturing of the beach grass--a plant allied in habits, if not in
+botanical character, to the arundo--has been attended with very
+injurious effects in Massachusetts. Dr. Dwight, after referring to the
+laws for its propagation, already cited, says: "The benefit of this
+useful plant, and of these prudent regulations, is, however, in some
+measure lost. There are in Province Town, as I was informed, one hundred
+and forty cows. These animals, being stinted in their means of
+subsistence, are permitted to wander, at times, in search of food. In
+every such case, they make depredations on the beach grass, and prevent
+its seeds from being formed. In this manner the plant is ultimately
+destroyed."--_Travels_, iii, p. 94.
+
+On page 101 of the same volume, the author mentions an instance of great
+injury from this cause. "Here, about one thousand acres were entirely
+blown away to the depth, in many places, of ten feet. * * * Not a green
+thing was visible except the whortleberries, which tufted a few lonely
+hillocks rising to the height of the original surface and prevented by
+this defence from being blown away also. These, although they varied the
+prospect, added to the gloom by their strongly picturesque appearance,
+by marking exactly the original level of the plain, and by showing us in
+this manner the immensity of the mass which had been thus carried away
+by the wind. The beach grass had been planted here, and the ground had
+been formerly enclosed; but the gates had been left open, and the cattle
+had destroyed this invaluable plant."
+
+[463] ANDRESEN, _Om Klitformationen_, pp. 237, 240.
+
+[464] "These plantations, perseveringly continued from the time of
+Bremontier now cover more than 40,000 hectares, and compose forests
+which are not only the salvation of the department, but constitute its
+wealth."--CLAVE, _Etudes Forestieres_, p. 254.
+
+Other authors have stated the plantations of the French dunes to be much
+more extensive.
+
+[465] KRUSE, _Duenenbau_, pp. 34, 38, 40.
+
+[466] These processes are substantially similar to those employed in the
+pineries of the Carolinas, but they are better systematized and more
+economically conducted in France. In the latter country, all the
+products of the pine, even to the cones, find a remunerating market,
+while, in America, the price of resin is so low, that in the fierce
+steamboat races on the great rivers, large quantities of it are thrown
+into the furnaces to increase the intensity of the fires. In a carefully
+prepared article on the Southern pineries published in an American
+magazine--I think Harper's--a few years ago, it was stated that the
+resin from the turpentine distilleries was sometimes allowed to run to
+waste; and the writer, in one instance, observed a mass, thus rejected
+as rubbish, which was estimated to amount to two thousand barrels. See
+_Appendix_, No. 62.
+
+[467] ANDRESEN, _Om Klitformationen_, pp. 78, 262, 275.
+
+[468] LAVAL, _Memoire sur les Dunes du Golfe de Gascogne, Annales des
+Ponts et Chaussees_, 1847, 2me semestre, p. 261. See _Appendix_, No.
+63.
+
+[469] There are extensive ranges of dunes on various parts of the coasts
+of the British Islands, but I find no estimate of their area. Pannewitz
+(_Anleitung zam Anbau der Sandflaechen_), as cited by Andresen (_Om
+Klitformationen_, p. 45), states that the drifting sands of Europe,
+including, of course, sand plains as well as dunes, cover an extent of
+21,000 square miles. This is, perhaps, an exaggeration, though there is,
+undoubtedly, much more desert land of this description on the European
+continent than has been generally supposed. There is no question that
+most of this waste is capable of reclamation by simple planting, and no
+mode of physical improvement is better worth the attention of civilized
+Governments than this.
+
+There are often serious objections to extensive forest planting on soils
+capable of being otherwise made productive, but they do not apply to
+sand wastes, which, until covered by woods, are not only a useless
+incumbrance, but a source of serious danger to all human improvements in
+the neighborhood of them.
+
+[470] BOITEL, _Mise en valeur des Terres pauvres par le Pin maritime_,
+pp. 212, 218.
+
+[471] See _Appendix_, No. .
+
+[472] For details, consult ANDRESEN, _Om Klitformationen_, pp. 223, 236.
+
+[473] When the deposit is not very deep, and the adjacent land lying to
+the leeward of the prevailing winds is covered with water, or otherwise
+worthless, the surface is sometimes freed from the drifts by repeated
+harrowings, which loosen the sand, so that the wind takes it up and
+transports it to grounds where accumulations of it are less injurious.
+
+[474] _Travels and Researches in Chaldaea_, chap. ix.
+
+[475] _Etudes Forestieres_, p. 253.
+
+[476] LAVERGNE, _Economie Rurale de la France_, p. 300, estimates the
+area of the Landes of Gascony at 700,000 hectares, or about 1,700,000
+acres. The same author states (p. 304), that when the Moors were driven
+from Spain by the blind cupidity and brutal intolerance of the age, they
+demanded permission to establish themselves in this desert; but
+political and religious prejudices prevented the granting of this
+liberty. At this period the Moors were a far more cultivated people than
+their Christian persecutors, and they had carried many arts, that of
+agriculture especially, to a higher pitch than any other European
+nation. But France was not wise enough to accept what Spain had cast
+out, and the Landes remained a waste for three centuries longer. See
+_Appendix_, No. 64.
+
+The forest of Fontainebleau, which contains above 40,000 acres, is not a
+plain, but its soil is composed almost wholly of sand, interspersed with
+ledges of rock. The sand forms not less than ninety-eight per cent. of
+the earth, and, as it is almost without water, it would be a drifting
+desert but for the artificial propagation of forest trees upon it.
+
+[477] _Economie Rurale de la Belgique, par_ EMILE DE LAVELEYE, _Revue
+des Deux Mondes_, Juin, 1861, pp. 617-644.
+
+[478] _Geognosie_, ii, p. 1173.
+
+[479] According to HOHENSTEIN, _Der Wald_, pp. 228, 229, an extensive
+plantation of pines--a tree new to Southern Russia--was commenced in
+1842, on the barren and sandy banks of the Ingula, near Elisabethgrod,
+and has met with very flattering success. Other experiments in
+sylviculture at different points on the steppes promise valuable
+results.
+
+[480] "Sixteen years ago," says an Odessa landholder, "I attempted to
+fix the sand of the steppes, which covers the rocky ground to the depth
+of a foot, and forms moving hillocks with every change of wind. I tried
+acacias and pines in vain; nothing would grow in such a soil. At length
+I planted the varnish tree, or _ailanthus_, which succeeded completely
+in binding the sand." This result encouraged the proprietor to extend
+his plantations over both dunes and sand steppes, and in the course of
+sixteen years this rapidly growing tree had formed real forests. Other
+landowners have imitated his example with great advantage.--RENTSCH,
+_Der Wald_, p. 44, 45.
+
+[481] _Souvenirs d'un Naturaliste_, i, pp. 204 _et seqq._
+
+[482] "If we suppose the narrow isthmus of Central America to be sunk in
+the ocean, the warm equatorial current would no longer follow its
+circuitous route around the Gulf of Mexico, but pour itself through the
+new opening directly into the Pacific. We should then lose the warmth of
+the Gulf Stream, and cold polar currents flowing farther southward would
+take its place and be driven upon our coasts by the western winds. The
+North Sea would resemble Hudson's Bay, and its harbors be free from ice
+at best only in summer. The power and prosperity of its coasts would
+shrivel under the breath of winter, as a medusa thrown on shore shrinks
+to an insignificant film under the influence of the destructive
+atmosphere. Commerce, industry, fertility of soil, population, would
+disappear, and the vast waste--a new Labrador--would become a worthless
+appendage of some clime more favored by nature."--HARTWIG, _Das Leben
+des Meeres_, p. 70.
+
+[483] I know nothing of Captain Allen's work but its title and its
+subject. Very probably he may have anticipated many of the following
+speculations, and thrown light on points upon which I am ignorant.
+
+[484] "Some haue writt[=e], that by certain kings inhabiting aboue, the
+_Nilus_ should there be stopped; & at a time prefixt, let loose vpon a
+certaine tribute payd them by the _Aegyptians_. The error springing
+perhaps fr[=o] a truth (as all wandring reports for the most part doe)
+in that the _Sultan_ doth pay a certaine annuall summe to the _Abissin_
+Emperour for not diuerting the course of the Riuer, which (they say) he
+may, or impouerish it at the least."--GEORGE SANDYS, _A Relation of a
+Journey, etc._, p. 98.
+
+[485] The Recca, a river with a considerable current, has been
+satisfactorily identified with a stream flowing through the cave of
+Trebich, and with the Timavo--the Timavus of Virgil and the ancient
+geographers--which empties through several mouths into the Adriatic
+between Trieste and Aquileia. The distance from Trieste to a suitable
+point in the grotto of Trebich is thought to be less than three miles,
+and the difficulties in the way of constructing a tunnel do not seem
+formidable. The works of Schmidl, _Die Hoehlen des Karstes_, and _Der
+unterirdische Lauf der Recca_, are not common out of Germany, but the
+reader will find many interesting facts derived from them in two
+articles entitled _Der unterirdische Lauf der Recca_, in _Aus der
+Natur_, xx, pp. 250-254, 263-266.
+
+[486] BARTH, _Wanderungen durch die Kuesten des Mittelmeeres_, i, p. 353.
+In a note on page 380, of the same volume, Barth cites Strabo as
+asserting that a similar practice prevailed in Iapygia; but it may be
+questioned whether the epithet [Greek: tracheia], applied by Strabo to
+the original surface, necessarily implies that it was covered with a
+continuous stratum of rock.
+
+[487] PARTHEY, _Wanderungen durch Sicilien und die Levante_, i, p. 404.
+
+[488] _Geognostische Studien am Meeres Ufer_, LEONHARD und BRONN,
+_Jahrbuch_, 1841, pp. 25, 26.
+
+[489] KOHL, _Schleswig-Holstein_, ii, p. 45.
+
+[490] _Wanderungen durch Sicilien und die Levante_, i, p. 406.
+
+[491] LANDGREBE, _Naturgeschichte der Vulkane_, ii, pp. 19, 20.
+
+[492] Soon after the current issues from the volcano, it is covered
+above and at its sides, and finally in front, with scoriae, formed by the
+cooling of the exposed surface, which bury and conceal the fluid mass.
+The stream rolls on under the coating, and between the walls of scoriae,
+and it was the lateral crust which was broken through by the workmen
+mentioned in the text.
+
+The distance to which lava flows, before its surface begins to solidify,
+depends on its volume, its composition, its temperature and that of the
+air, the force with which it is ejected, and the inclination of the
+declivity over which it runs. In most cases it is difficult to approach
+the current at points where it is still entirely fluid, and hence
+opportunities of observing it in that condition are not very frequent.
+In the eruption of February, 1850, on the east side of Vesuvius, I went
+quite up to one of the outlets. The lava shot out of the orifice upward
+with great velocity, like the water from a spring, in a stream eight or
+ten feet in diameter, throwing up occasionally volcanic bombs, but it
+immediately spread out on the declivity down which it flowed, to the
+width of several yards. It continued red hot in broad daylight, and
+without a particle of scoriae on its surface, for a course of at least
+one hundred yards. At this distance, the suffocating, sulphurous vapors
+became so dense that I could follow the current no farther. The
+undulations of the surface were like those of a brook swollen by rain. I
+estimated the height of the waves at five or six inches by a breadth of
+eighteen or twenty. To the eye, the fluidity of the lava seemed as
+perfect as that of water, but masses of cold lava weighing ten or
+fifteen pounds floated upon it like cork.
+
+The heat emitted by lava currents seems extremely small when we consider
+the temperature required to fuse such materials and the great length of
+time they take in cooling. I saw at Nicolosi ancient oil jars, holding a
+hundred gallons or more, which had been dug out from under a stream of
+old lava above that town. They had been very slightly covered with
+volcanic ashes before the lava flowed over them, but the lead with which
+holes in them had been plugged was not melted. The current that buried
+Mompiliere in 1669 was thirty-five feet thick, but marble statues, in a
+church over which the lava formed an arch, were found uncalcined and
+uninjured in 1704. See SCROPE, _Volcanoes_, chap. VI. Sec. 6.
+
+[493] FERRARA, _Descrizione dell' Etna_, p. 108.
+
+[494] LANGREBE, _Naturgeschichte der Vulkane_, ii, p. 82.
+
+[495] _Physikalische Geographie_, p. 168. Beds of peat, accidentally set
+on fire, sometimes continue to burn for months. I take the following
+account of a case of this sort from a recent American journal:
+
+"A CURIOUS PHENOMENON.--When the track of the railroad between Brunswick
+and Bath was being graded, in crossing a meadow near the populous
+portion of the latter city, the 'dump' suddenly took on a sinking
+symptom, and down went the twenty feet fill of gravel, clay, and broken
+rocks, out of sight, and it was a long, _long_ time before dirt trains
+could fill the capacious stomach that seemed ready to receive all the
+solid material that could be turned into it. The difficulty was at
+length overcome, but all along the side of the sinkage the earth was
+thrown up, broken into yawning chasms, and the surface was thus elevated
+above its old watery level. Since that time this ground, thus slightly
+elevated, has been cultivated, and has yielded enormously of whatever
+the owner seemed disposed to plant upon it. Some three months ago, by
+some means unknown to us, the underlying peat took fire, and for weeks,
+as we had occasion to pass it, we noticed the smoke arising from the
+smouldering combustion beneath the surface. Rains fell, but the fire
+burned, and the smoke continued to arise. Monday we had occasion to pass
+the spot, and though nearly a week's rain had been drenching the ground,
+and though the surface was whitened with snow, and though pools of water
+were standing upon the surface in the immediate neighborhood, still the
+everlasting subterranean fire was burning, and the smoke arising through
+the snow."
+
+[496] One of the sublimest, and at the same time most fearful
+suggestions that have been prompted by the researches of modern science,
+was made by Babbage in the ninth chapter of his _Ninth Bridgewater
+Treatise_. I have not the volume at hand, but the following explanation
+will recall to the reader, if it does not otherwise make intelligible,
+the suggestion I refer to.
+
+No atom can be disturbed in place, or undergo any change of temperature,
+of electrical state, or other material condition, without affecting, by
+attraction or repulsion or other communication, the surrounding atoms.
+These, again, by the same law, transmit the influence to other atoms,
+and the impulse thus given extends through the whole material universe.
+Every human movement, every organic act, every volition, passion, or
+emotion, every intellectual process, is accompanied with atomic
+disturbance, and hence every such movement, every such act or process
+affects all the atoms of universal matter. Though action and reaction
+are equal, yet reaction does not restore disturbed atoms to their former
+place and condition, and consequently the effects of the least material
+change are never cancelled, but in some way perpetuated, so that no
+action can take place in physical, moral, or intellectual nature,
+without leaving all matter in a different state from what it would have
+been if such action had not occurred. Hence, to use language which I
+have employed on another occasion: there exists, not alone in the human
+conscience or in the omniscience of the Creator, but in external
+material nature, an ineffaceable, imperishable record, possibly legible
+even to created intelligence, of every act done, every word uttered,
+nay, of every wish and purpose and thought conceived by mortal man, from
+the birth of our first parent to the final extinction of our race; so
+that the physical traces of our most secret sins shall last until time
+shall be merged in that eternity of which not science, but religion
+alone, assumes to take cognizance.
+
+
+
+
+APPENDIX.
+
+
+No. 1 (page 19, _note_). It may be said that the cases referred to in
+the note on p. 19--and indeed all cases of a supposed acclimation
+consisting in physiological changes--are instances of the origination of
+new varieties by natural selection, the hardier maize, tomato, and other
+vegetables of the North, being the progeny of seeds of individuals
+endowed, exceptionally, with greater power of resisting cold than
+belongs in general to the species which produced them. But, so far as
+the evidence of change of climate, from a difference in vegetable
+growth, is concerned, it is immaterial whether we adopt this view or
+maintain the older and more familiar doctrine of a local modification of
+character in the plants in question.
+
+No. 2 (page 24, _note_). The adjectives of direction in _-erly_ are not
+unfrequently used to indicate, in a loose way, the course of winds
+blowing from unspecified points between N.E. and S.E.; S.E. and S.W.;
+S.W. and N.W. or N.W. and N.E. If the employment of these words were
+understood to be limited to thus expressing a direction nearer to the
+cardinal point from whose name the adjective is taken than to any other
+cardinal point, they would be valuable elements of English
+meteorological nomenclature.
+
+No. 3 (page 31). I find a confirmation of my observations on the habits
+of the beaver as a geographical agency, in a report of the proceedings
+of the British Association, in the London Athenaeum of October 8, 1864,
+p. 469. It is there stated that Viscount Milton and Dr. Cheadle, in an
+expedition across the Rocky Mountains by the Yellow Head, or Leather
+Pass, observed that "a great portion of the country to the east of the
+mountains" had been "completely changed in character by the agency of
+the beaver, which formerly existed here in enormous numbers. The shallow
+valleys were formerly traversed by rivers and chains of lakes which,
+dammed up along their course at numerous points, by the work of those
+animals, have become a series of marshes in various stages of
+consolidation. So complete has this change been, that hardly a stream is
+found for a distance of two hundred miles, with the exception of the
+large rivers. The animals have thus destroyed, by their own labors, the
+waters necessary to their own existence."
+
+When the process of "consolidation" shall have been completed, and the
+forest reestablished upon the marshes, the water now diffused through
+them will be collected in the lower or more yielding portions, cut new
+channels for their flow, become running brooks, and thus restore the
+ancient aspect of the surface.
+
+No. 4 (page 33, _note_). The lignivorous insects that attack living
+trees almost uniformly confine their ravages to trees already unsound or
+diseased in growth from the depredations of leaf-eaters, such as
+caterpillars and the like, or from other causes. The decay of the tree,
+therefore, is the cause not the consequence of the invasions of the
+borer. This subject has been discussed by Perris in the _Annales de la
+Societe Entomologique de la France_, for 1851 (?), and his conclusions
+are confirmed by the observations of Samanos, who quotes, at some
+length, the views of Perris. "Having, for fifteen years," says the
+latter author, "incessantly studied the habits of lignivorous insects in
+one of the best wooded regions of France, I have observed facts enough
+to feel myself warranted in expressing my conclusions, which are: that
+insects in general--I am not speaking of those which confine their
+voracity to the leaf--do not attack trees in sound health, and they
+assail those only whose normal conditions and functions have been by
+some cause impaired."
+
+See, more fully, Samanos, _Traite de la Culture du Pin Maritime_, Paris,
+1864, pp. 140-145.
+
+No. 5 (page 34, _note_). Very interesting observations, on the agency of
+the squirrel and other small animals in planting and in destroying nuts
+and other seeds of trees, may be found in a paper on the Succession of
+Forests in Thoreau's _Excursions_, pp. 135 _et seqq._
+
+I once saw several quarts of beech-nuts taken from the winter quarters
+of a family of flying squirrels in a hollow tree. The kernels were
+neatly stripped of their shells and carefully stored in a dry cavity.
+
+No. 6 (page 40, _note_). Schroeder van der Kolk, in _Het Verschil
+tusschen den Psychischen Aanleg van het Dier en van den Mensch_, cites
+from Burdach and other authorities many interesting facts respecting
+instincts lost, or newly developed and become hereditary, in the lower
+animals, and he quotes Aristotle and Pliny as evidence that the common
+quadrupeds and fowls of our fields and our poultry yards were much less
+perfectly domesticated in their times than long, long ages of servitude
+have now made them.
+
+Perhaps the half-wild character ascribed by P. Laestadius and other
+Swedish writers to the reindeer of Lapland, may be in some degree due to
+the comparative shortness of the period during which he has been
+partially tamed. The domestic swine bred in the woods of Hungary and
+the buffaloes of Southern Italy are so wild and savage as to be very
+dangerous to all but their keepers. The former have relapsed into their
+original condition, the latter have not yet been reclaimed from it.
+
+Among other instances of obliterated instincts, Schroeder van der Kolk
+states that in Holland, where, for centuries, the young of the cow has
+been usually taken from the dam at birth and fed by hand, calves, even
+if left with the mother, make no attempt to suck; while in England,
+where calves are not weaned until several weeks old, they resort to the
+udder as naturally as the young of wild quadrupeds.--_Ziel en Ligchaam_,
+p. 128, _n._
+
+No. 7 (page 60, _first note_). At Pie di Mulera, at the outlet of the
+Val Anzasca, near the principal hotel, is a vine measuring thirty-one
+inches in circumference. The door of the chapter-hall in the cloister of
+the church of San Giovanni, at Saluzzo, is of vine wood, and the boards
+of which the panels were made could not have been less than ten inches
+wide. Statues and other objects of considerable dimensions, of vine
+wood, are mentioned by ancient writers.
+
+No. 8 (page 63, _second note_). Cartier, A. D. 1535-'6, mentions "vines,
+great melons, cucumbers, gourds [courges], pease, beans of various
+colors, but not like ours," as common among the Indians of the banks of
+the St. Lawrence.--_Bref Recit_, etc., reprint. Paris, 1863, pp. 13, a;
+14, b; 20, b; 31, a.
+
+No. 8 (page 65, _second paragraph_). It may be considered very highly
+probable, if not certain, that the undiscriminating herbalists of the
+sixteenth century must have overlooked many plants native to this
+island. An English botanist, in an hour's visit to Aden, discovered
+several species of plants on rocks always reported, even by scientific
+travellers, as absolutely barren. But after all, it appears to be well
+established that the original flora of St. Helena was extremely limited,
+though now counting hundreds of species.
+
+No. 9 (page 66, _first note_). Although the vine _genus_ is very
+catholic and cosmopolite in its habits, yet particular _varieties_ are
+extremely fastidious and exclusive in their requirements as to soil and
+climate. The stocks of many celebrated vineyards lose their peculiar
+qualities by transplantation, and the most famous wines are capable of
+production only in certain well-defined, and for the most part narrow
+districts. The Ionian vine which bears the little stoneless grape known
+in commerce as the Zante currant, has resisted almost all efforts to
+naturalize it elsewhere, and is scarcely grown except in two or three of
+the Ionian islands and in a narrow territory on the northern shores of
+the Morea.
+
+No. 10 (page 68, _first note_). In most of the countries of Southern
+Europe, sheep and beeves are wintered upon the plains, but driven in the
+summer to mountain pastures at many days' distance from the homesteads
+of their owners. They transport seeds in their coats in both directions,
+and hence Alpine plants often shoot up at the foot of the mountains, the
+grasses of the plain on the borders of the glaciers; but in both cases,
+they usually fail to propagate themselves by ripening their seed. This
+explains the scattered tufts of common clover, with pale and flaccid
+blossoms, which are sometimes seen at heights exceeding 7,000 feet above
+the sea.
+
+No. 11 (page 73, _last paragraph_). The poisonous wild parsnip, which is
+very common in New England, is popularly believed to be identical with
+the garden parsnip, and differenced only by conditions of growth, a
+richer soil depriving it, it is said, of its noxious properties. Many
+wild medicinal plants, such as pennyroyal for example, are so much less
+aromatic and powerful, when cultivated in gardens, than when self-sown
+on meagre soils, as to be hardly fit for use.
+
+No. 12 (page 74, _second note_). See in Thoreau's _Excursions_, an
+interesting description of the wild apple-trees of Massachusetts.
+
+No. 13 (page 86, _first paragraph_). It is said at Courmayeur that a
+very few ibexes of a larger variety than those of the Cogne mountains,
+still linger about the Grande Jorasse.
+
+No. 14 (page 92, _first note_). In Northern and Central Italy, one often
+sees hillocks crowned with grove-like plantations of small trees, much
+resembling large arbors. These serve to collect birds, which are
+entrapped in nets in great numbers. These plantations are called
+_ragnaje_, and the reader will find, in Bindi's edition of Davanzati, a
+very pleasant description of a ragnaja, though its authorship is not now
+ascribed to that eminent writer.
+
+No. 15 (page 93, _second note_). The appearance of the dove-like grouse,
+_Tetrao paradoxus_, or _Syrrhaptes Pallasii_, in various parts of
+Europe, in 1859 and the following years, is a noticeable exception to
+the law of regularity which seems to govern the movements and determine
+the habitat of birds. The proper home of this bird is the steppes of
+Tartary, and it is not recorded to have been observed in Europe, or at
+least west of Russia, until the year abovementioned, when many flocks of
+twenty or thirty, and even a hundred individuals, were seen in Bohemia,
+Germany, Holland, Denmark, England, Ireland, and France. A considerable
+flock frequented the Frisian island of Borkum for more than five months.
+It was hoped they would breed and remain permanently in the island, but
+this expectation has been disappointed, and the steppe-grouse seems to
+have disappeared again altogether.
+
+No. 16 (page 94, _note_). From an article by A. Esquiros, in the _Revue
+des Deux Mondes_ for Sept. 1, 1864, entitled, _La vie Anglaise_, p. 119,
+it appears that such occurrences as that stated in the note are not
+unfrequent on the British coast.
+
+No. 17 (page 100, _first paragraph_). I cannot learn that caprification
+is now practised in Italy, but it is still in use in Greece.
+
+No. 18 (page 112, _first note_). The recent great multiplication of
+vipers in some parts of France, is a singular and startling fact.
+
+Toussenel, quoting from official documents, states, that upon the offer
+of a reward of fifty centimes, or ten cents, a head, _twelve thousand_
+vipers were brought to the prefect of a single department, and that in
+1859 fifteen hundred snakes and twenty quarts of snakes' eggs were found
+under a farm-house hearthstone. The granary, the stables, the roof, the
+very beds swarmed with serpents, and the family were obliged to abandon
+its habitation. Dr. Viaugrandmarais, of Nantes, reported to the prefect
+of his department more than two hundred recent cases of viper bites,
+twenty-four of which proved fatal.--_Tristia_, p. 176 _et seqq._
+
+No. 19 (page 121, _first note_). The Beduins are little given to the
+chase, and seldom make war on the game birds and quadrupeds of the
+desert. Hence the wild animals of Arabia are less timid than those of
+Europe. On one occasion, when I was encamped during a sand storm of some
+violence in Arabia Petraea, a wild pigeon took refuge in one of our tents
+which had not been blown down, and remained quietly perched on a boy in
+the midst of four or five persons, until the storm was over, and then
+took his departure, _insalutato hospite_.
+
+No. 20 (page 122). It is possible that time may modify the habits of the
+fresh water fish of the North American States, and accommodate them to
+the now physical conditions of their native waters. Hence it may be
+hoped that nature, even unaided by art, will do something toward
+restoring the ancient plenty of our lakes and rivers. The decrease of
+our fresh water fish cannot be ascribed alone to exhaustion by fishing,
+for in the waters of the valleys and flanks of the Alps, which have been
+inhabited and fished ten times as long by a denser population, fish are
+still very abundant, and they thrive and multiply under circumstances
+where no American species could live at all. On the southern slope of
+those mountains, trout are caught in great numbers, in the swift streams
+which rush from the glaciers, and where the water is of icy coldness,
+and so turbid with particles of fine-ground rock, that you cannot see an
+inch below the surface. The glacier streams of Switzerland, however, are
+less abundant in fish.
+
+No. 21 (page 131, _note_). Vaupell, though agreeing with other writers
+as to the injury done to the forest by most domestic animals--which he
+illustrates in an interesting way in his posthumous work, _The Danish
+Woods_--thinks, nevertheless, that at the season when the mast is
+falling swine are rather useful than otherwise to forests of beech and
+oak, by treading into the ground and thus sowing beechnuts and acorns,
+and by destroying moles and mice.--_De Danske Skore_, p. 12.
+
+No. 22 (page 135, _note_). The able authors of Humphreys and Abbot's
+most valuable Report on the Physics and Hydraulics of the Mississippi,
+conclude that the delta of that river began its encroachments on the
+Gulf of Mexico not more than 4,400 years ago, before which period they
+suppose the Mississippi to have been "a comparatively clear stream,"
+conveying very little sediment to the sea. The present rate of advance
+of the delta is 262 feet a year, and there are reasons for thinking that
+the amount of deposit has long been approximately constant.--_Report_,
+pp. 435, 436.
+
+The change in the character of the river must, if this opinion is well
+founded, be due to some geological revolution, or at least convulsion,
+and the hypothesis of the former existence of one or more great lakes in
+its upper valley, whose bottoms are occupied by the present prairie
+region, has been suggested. The shores of these supposed lakes have not,
+I believe, been traced, or even detected, and we cannot admit the truth
+of this hypothesis without supposing changes much more extensive than
+the mere bursting of the barrier which confined the waters.
+
+No. 23 (page 143, _note_). See on this subject a paper by J. Jamin, in
+the _Revue des Deux Mondes_ for Sept. 15, 1864; and, on the effects of
+human industry on the atmosphere, an article in _Aus der Natur_, vol.
+29, 1864, pp. 443, 449, 465 _et seqq._
+
+No. 24 (page 159, _second paragraph_). All evergreens, even the
+broad-leaved trees, resist frosts of extraordinary severity better than
+the deciduous trees of the same climates. Is not this because the vital
+processes of trees of persistent foliage are less interrupted during
+winter than those of trees which annually shed their leaves, and
+therefore more organic heat is developed?
+
+No. 25 (page 191, _first paragraph_). In discussing the influence of
+mountains on precipitation, meteorologists have generally treated the
+popular belief, that mountains "attract" to them clouds floating within
+a certain distance from them, as an ignorant prejudice, and they ascribe
+the appearance of clouds about high peaks solely to the condensation of
+the humidity of the air carried by atmospheric currents up the slopes of
+the mountain to a colder temperature. But if mountains do not really
+draw clouds and invisible vapors to them, they are an exception to the
+universal law of attraction. The attraction of the small Mount
+Shehallien was found sufficient to deflect from the perpendicular, by a
+measurable quantity, a plummet weighing but a few ounces. Why, then,
+should not greater masses attract to them volumes of vapor weighing
+hundreds of tons, and floating freely in the atmosphere within moderate
+distances of the mountains?
+
+No. 26 (page 198, _note_). Elisee Redus ascribes the diminution of the
+ponds which border the dunes of Gascony to the absorption of their water
+by the trees which have been planted upon the sands.--_Revue des Deux
+Mondes_, 1 Aug., 1863, p. 694.
+
+No. 27 (page 219, _note_). The waste of wood in European carpentry was
+formerly enormous, the beams of houses being both larger and more
+numerous than permanence or stability required. In examining the
+construction of the houses occupied by the eighty families which inhabit
+the village of Faucigny, in Savoy, in 1834, the forest inspector found
+that _fifty thousand_ trees had been employed in building them. The
+builders "seemed," says Hudry-Menos, "to have tried to solve the problem
+of piling upon the walls the largest quantity of timber possible without
+crushing them."--_Revue des Deux Mondes_, 1 June, 1864, p. 601.
+
+No. 28 (page 231, _note_). In a remarkable pamphlet, to which I shall
+have occasion to refer more than once hereafter, entitled _Avant-projet
+pour la creation d'un sol fertile a la surface des Landes de Gascogne_,
+Duponchel argues with much force, that the fertilizing properties of
+river-slime are generally due much more to its mineral than to its
+vegetable constituents.
+
+No. 29 (page 265, _note_). Even the denser silicious stones are
+penetrable by fluids and the coloring matter they contain, to such an
+extent that agates and other forms of silex may be artificially stained
+through their substance. This art was known to and practised by the
+ancient lapidaries, and it has been revived in recent times.
+
+No. 30 (page 268). There is good reason for thinking that many of the
+earth and rock slides in the Alps occurred at an earlier period than the
+origin of the forest vegetation which, in later ages, covered the flanks
+of those mountains. See _Bericht ueber die Untersuchung der
+Schweizerischen Hochgebirgswaldungen_. 1862. P. 61.
+
+Where more recent slides have been again clothed with woods, the trees,
+shrubs, and smaller plants which spontaneously grow upon them are
+usually of different species from those observed upon soil displaced at
+remote periods. This difference is so marked that the site of a slide
+can often be recognized at a great distance by the general color of the
+foliage of its vegetation.
+
+No. 31 (page 286, _note_). It should have been observed that the
+venomous principle of poisonous mushrooms is not decomposed and rendered
+innocent by the process described in the _note_. It is merely extracted
+by the acidulated or saline water employed for soaking the plants, and
+care should be taken that this water be thrown away out of the reach of
+mischief.
+
+No. 32 (page 293, _note_). Gaudry estimates the ties employed in the
+railways of France at thirty millions, to supply which not less than two
+millions of large trees have been felled. These ties have been, upon the
+average, at least once renewed, and hence we must double the number of
+ties and of trees required to furnish them.--_Revue des Deux Mondes_, 15
+July, 1863, p. 425.
+
+No. 33 (page 294, _second paragraph of note_). After all, the present
+consumption of wood and timber for fuel and other domestic and rural
+purposes, in many parts of Europe, seems incredibly small to an
+American. In rural Switzerland, the whole supply of firewood,
+fuel for small smitheries, dairies, breweries, brick and lime
+kilns, distilleries, fences, furniture, tools, and even house
+building--exclusive of the small quantity derived from the trimmings
+of fruit trees, grape vines and hedges, and from decayed fences and
+buildings--does not exceed an average of _two hundred and thirty cubic
+feet_, or less than two cords, a year per household. The average
+consumption of wood in New England for domestic fuel alone, is from five
+to ten times as much as Swiss families require for all the uses above
+enumerated. But the existing habitations of Switzerland are sufficient
+for a population which increases but slowly, and in the peasants' houses
+but a single room is usually heated. See _Bericht ueber die Untersuchung
+der Schweiz. Hochgebirgswaldungen_, pp. 85-89.
+
+No. 34 (page 304). Among more recent manuals may be mentioned: _Les
+Etudes de Maitre Pierre._ Paris, 1864. 12mo; BAZELAIRE, _Traite de
+Reboisement_. 2d edition, Paris, 1864; and, in Italian, SIEMONI,
+_Manuale teorico-pratico d'arte Forestale_. Firenze, 1864. 8vo. A very
+important work has lately been published in France by Viscount de
+Courval, which is known to me only by a German translation published at
+Berlin, in 1864, under the title, _Das Aufaesten der Waldbaeume_. The
+principal feature of De Courval's very successful system of
+sylviculture, is a mode of trimming which compels the tree to develop
+the stem by reducing the lateral ramification. Beginning with young
+trees, the buds are rubbed off from the stems, and superfluous lateral
+shoots are pruned down to the trunk. When large trees are taken in hand,
+branches which can be spared, and whose removal is necessary to obtain a
+proper length of stem, are very smoothly cut off quite close to the
+trunk, and the exposed surface is _immediately_ brushed over with
+mineral-coal tar. When thus treated, it is said that the healing of the
+wound is perfect, and without any decay of the tree.
+
+No. 35 (page 313). The most gorgeous autumnal coloring I have observed
+in the vegetation of Europe, has been in the valleys of the Durance and
+its tributaries in Dauphiny. I must admit that neither in variety nor in
+purity and brilliancy of tint, does this coloring fall much, if at all,
+short of that of the New England woods. But there is this difference: in
+Dauphiny, it is only in small shrubs that this rich painting is seen,
+while in North America the foliage of large trees is dyed in full
+splendor. Hence the American woodland has fewer broken lights and more
+of what painters call breadth of coloring. Besides this, the arrangement
+of the leafage in large globular or conical masses, affords a wider
+scale of light and shade, thus aiding now the gradation, now the
+contrast of tints, and gives the American October landscape a softer and
+more harmonious tone than marks the humble shrubbery of the forest
+hill-sides of Dauphiny.
+
+Thoreau--who was not, like some very celebrated landscape critics of the
+present day, an outside spectator of the action and products of natural
+forces, but, in the old religious sense, an _observer_ of organic
+nature, living, more than almost any other descriptive writer, among and
+with her children--has a very eloquent paper on the "Autumnal Tints" of
+the New England landscape.--See his _Excursions_, pp. 215 _et seqq._
+
+Few men have personally noticed so many facts in natural history
+accessible to unscientific observation as Thoreau, and yet he had never
+seen that very common and striking spectacle, the phosphorescence of
+decaying wood, until, in the latter years of his life, it caught his
+attention in a bivouac in the forests of Maine. He seems to have been
+more excited by this phenomenon than by any other described in his
+works. It must be a capacious eye that takes in all the visible facts in
+the history of the most familiar natural object.--_The Maine Woods_, p.
+184.
+
+"The luminous appearance of bodies projected against the sky adjacent to
+the rising" or setting sun, so well described in Professor Necker's
+Letter to Sir David Brewster, is, as Tyndall observes, "hardly ever seen
+by either guides or travellers, though it would seem, _prima facie_,
+that it must be of frequent occurrence." See TYNDALL, _Glaciers of the
+Alps_. Part I. Second ascent of Mont Blanc.
+
+Judging from my own observation, however, I should much doubt whether
+this brilliant phenomenon can be so often seen in perfection as would be
+expected; for I have frequently sought it in vain at the foot of the
+Alps, under conditions apparently otherwise identical with those where,
+in the elevated Alpine valleys, it shows itself in the greatest
+splendor.
+
+No. 36 (page 314). European poets, whose knowledge of the date palm is
+not founded on personal observation, often describe its trunk as not
+only slender, but particularly _straight_. Nothing can be farther from
+the truth. When the Orientals compare the form of a beautiful girl to
+the stem of the palm, they do not represent it as rigidly straight, but
+on the contrary as made up of graceful curves, which seem less like
+permanent outlines than like flowing motion. In a palm grove, the
+trunks, so far from standing planted upright like the candles of a
+chandelier, bend in a vast variety of curves, now leaning towards, now
+diverging from, now crossing, each other, and among a hundred you will
+hardly see two whose axes are parallel.
+
+No. 37 (page 316, _first note_). Charles Martin ascribes the power of
+reproduction by shoots from the stump to the cedar of Mount Atlas, which
+appears to be identical with the cedar of Lebanon.--_Revue des Deux
+Mondes_, 15 July, 1864, p. 315.
+
+No. 38 (page 332). In an interesting article on recent internal
+improvements in England, in the London Quarterly Review for January,
+1858, it is related that in a single rock cutting on the Liverpool and
+Manchester railway, 480,000 cubic yards of stone were removed; that the
+earth excavated and removed in the construction of English railways up
+to that date, amounted to a hundred and fifty million cubic yards, and
+that at the Round Down Cliff, near Dover, a single blast of nineteen
+thousand pounds of powder blew down a thousand million tons of chalk,
+and covered fifteen acres of land with the fragments.
+
+No. 39 (page 339). According to Reventlov, whose work is one of the best
+sources of information on the subject of diking-in tide-washed flats,
+_Salicornia herbacea_ appears as soon as the flat is raised high enough
+to be dry for three hours at ordinary ebb tide, or, in other words,
+where the ordinary flood covers it to a depth of not more than two feet.
+At a flood depth of one foot, the _Salicornia_ dies and is succeeded by
+various sand plants. These are followed by _Poa distans_ and _Poa
+maritima_ as the ground is raised by further deposits, and these plants
+finally by common grasses. The _Salicornia_ is preceded by _confervae_,
+growing in deeper water, which spread over the bottom, and when covered
+by a fresh deposit of slime reappear above it, and thus vegetable and
+alluvial strata alternate until the flat is raised sufficiently high for
+the growth of _Salicornia_.--_Om Marskdannelsen paa Vestkysten af
+Hertugdoemmet Slesvig_, pp. 7, 8.
+
+No. 40 (page 348, _note_). The drijftil employed for the ring dike of
+the Lake of Haarlem, was in part cut in sections fifty feet long by six
+or seven wide, and these were navigated like rafts to the spot where
+they were sunk to form the dike.--EMILE DE LAVELEYE, _Revue des Deux
+Mondes_, 15 Sept., 1863, p. 285.
+
+No. 41 (page 352, _last paragraph_). See on the influence of the
+improvements in question on tidal and other marine currents, Staring,
+_De Bodem van Nederland_, I. p. 279.
+
+Although the dikes of the Netherlands and the adjacent states have
+protected a considerable extent of coast from the encroachments of the
+sea, and have won a large tract of cultivable land from the dominion of
+the waters, it has been questioned whether a different method of
+accomplishing these objects might not have been adopted with advantage.
+It has been suggested that a system of inland dikes and canals, upon the
+principle of those which, as will be seen in a subsequent part of the
+chapter on the waters, have been so successfully employed in the Val di
+Chiana and in Egypt, might have elevated the low grounds above the ocean
+tides, by spreading over them the sediment brought down by the Rhine,
+the Maes, and the Scheld. If this process had been introduced in the
+Middle Ages and constantly pursued to our times, the superficial and
+coast geography, as well as the hydrography of the countries in
+question, would undoubtedly have presented an aspect very different from
+their present condition; and by combining the process with a system of
+maritime dikes, which would have been necessary, both to resist the
+advance of the sea and to retain the slime deposited by river overflows,
+it is possible that the territory of those states would have been as
+extensive as it now is, and, at the same time, more elevated by several
+feet. But it must be borne in mind that we do not know the proportions
+in which the marine deposits that form the polders have been derived
+from materials brought down by these rivers or from other more remote
+sources. Much of the river slime has no doubt been transported by marine
+currents quite beyond the reach of returning streams, and it is
+uncertain how far this loss has been balanced by earth washed by the sea
+from distant shores and let fall on the coasts of the Netherlands and
+other neighboring countries.
+
+We know little or nothing of the quantity of solid matter brought down
+by the rivers of Western Europe in early ages, but, as the banks of
+those rivers are now generally better secured against wash and abrasion
+than in former centuries, the sediment transported by them must be less
+than at periods nearer the removal of the primitive forests of their
+valleys. Kloeden states the quantity of sedimentary matter now annually
+brought down by the Rhine at Bonn to be sufficient only to cover a
+square English mile to the depth of a little more than a
+foot.--_Erdkunde_, I. p. 384.
+
+No. 42 (page 358, _first paragraph_). Meteorological observations have
+been regularly recorded at Zwanenburg, near the north end of the Lake of
+Haarlem, for more than a century, and since 1845 a similar register has
+been kept at the Helder, forty or fifty miles farther north. In
+comparing these two series of observations, it is found that about the
+end of the year 1852, when the drawing off of the waters of the Lake of
+Haarlem was completed, and the preceding summer had dried the grounds
+laid bare so as greatly to reduce the evaporable surface, a change took
+place in the relative temperature of the two stations. Taking the mean
+of every successive period of five days from 1845 to 1852, the
+temperature at Zwanenburg was thirty-three hundredths of a centigrade
+degree _lower_ than at the Helder. Since the end of 1852, the
+thermometer at Zwanenburg has stood, from the 11th of April to the 20th
+of September inclusive, twenty-two hundredths of a degree _higher_ than
+at the Helder, but from the 14th of October to the 17th of March, it has
+averaged one-tenth of a degree _lower_ than its mean between the same
+dates before 1853.
+
+There is no reasonable doubt that these differences are due to the
+draining of the lake. There has been less refrigeration from evaporation
+in summer, and the ground has absorbed more solar heat at the same
+period, while in the winter it has radiated more warmth then when it was
+covered with water. Doubtless the quantity of humidity contained in the
+atmosphere has also been affected by the same cause, but observations do
+not appear to have been made on that point. See KRECKE, _Het Klimaat van
+Nederland_, II. 64.
+
+No. 43 (page 358, _note_). In the course of the present year (1864),
+there have been several land slips on the borders of the Lake of Como,
+and in one instance the grounds of a villa lying upon the margin of the
+water suffered a considerable displacement. If the lake should be
+lowered to any considerable extent, in pursuance of the plan mentioned
+in the note on page 358, there is ground to fear that the steep shores
+of the lake might, at some points, be deprived of a lateral pressure
+requisite to their stability, and slide into the water as on the Lake of
+Lungern. See p. 356.
+
+No. 44 (page 369, _last paragraph but one of note_). In like manner,
+while the box, the cedar, the fir, the oak, the pine, "beams," and
+"timber," are very frequently mentioned in the Old Testament, not one of
+these words is found in the New, _except_ the case of the "beam in the
+eye," in the parable in Matthew and Luke.
+
+No. 45 (page 375, _note_). In all probability, the real change effected
+by human art in the superficial geography of Egypt, is the conversion of
+pools and marshes into dry land, by a system of transverse dikes, which
+compelled the flood water to deposit its sediment on the banks of the
+river instead of carrying it to the sea. The _colmate_ of modern Italy
+were thus anticipated in ancient Egypt.
+
+No. 46 (page 378). We have seen in _Appendix_, No. 42, _ante_, that the
+mean temperature of a station on the borders of the Lake of Haarlem--a
+sheet of water formerly covering sixty-two and a half square English
+miles--for the period between the 11th of April and the 20th of
+September, had been raised not less than a degree of Fahrenheit by the
+draining of that lake; or, to state the case more precisely, that the
+formation of the lake, which was a consequence of man's improvidence,
+had reduced the temperature one degree F. below the natural standard.
+The artificially irrigated lands of France, Piedmont, and Lombardy,
+taken together, are fifty times as extensive as the Lake of Haarlem, and
+they are situated in climates where evaporation is vastly more rapid
+than in the Netherlands. They must therefore, no doubt, affect the local
+climate to a far greater extent than has been observed in connection
+with the draining of the lake in question. I do not know that special
+observations have been made with a view to measure the climatic effects
+of irrigation, but in the summer I have often found the _morning_
+temperature, when the difference would naturally be least perceptible,
+on the watered plains of Piedmont, nine miles south of Turin, several
+degrees lower than that recorded at an observatory in the city.
+
+No. 47 (page 391, _note_). The Roman aqueduct known as the Pont du Gard,
+near Nismes, was built, in all probability, nineteen centuries ago. The
+bed of the river Gardon, a rather swift stream, which flows beneath it,
+can have suffered but a slight depression since the piers of the
+aqueduct were founded.
+
+No. 48 (page 393, _first note_). Duponchel makes the following
+remarkable statement: "The river Herault rises in a granitic region, but
+soon reaches calcareous formations, which it traverses for more than
+sixty kilometres, rolling through deep and precipitous ravines, into
+which the torrents are constantly discharging enormous masses of pebbles
+belonging to the hardest rocks of the Jurassian period. These debris,
+continually renewed, compose, even below the exit of the gorge where the
+river enters into a regular channel cut in a tertiary deposit, broad
+beaches, prodigious accumulations of rolled pebbles, extending several
+kilometres down the stream, but they diminish in size and weight so
+rapidly that above the mouth of the river, which is at a distance of
+thirty or thirty-five kilometres from the gorge, every trace of
+calcareous matter has disappeared from the sands of the bottom, which
+are exclusively silicious."--_Avant-projet pour la creation d'un sol
+fertile_, etc., p. 20.
+
+No. 49 (page 404, _first paragraph of second note_). The length of the
+lower course of the Po having been considerably increased by the filling
+up of the Adriatic with its deposits, the velocity of the current ought,
+_prima facie_, to have been diminished and its bed raised in proportion.
+There are grounds for believing that this has happened in the case of
+the Nile, and one reason why the same effect has not been more sensibly
+perceptible in the Po is, that the confinement of the current by
+continuous embankments gives it a high-water velocity sufficient to
+sweep out deposits let fall at lower stages and slower movements of the
+water. Torrential streams tend first to excavate, then to raise, their
+beds. No general law on this point can be stated in relation to the
+middle and lower course of rivers. The conditions which determine the
+question of the depression or elevation of a river bed are too
+multifarious, variable, and complex to be subjected to formulae, and they
+can scarcely even be enumerated. See, however, note on p. 431.
+
+No. 50 (page 406, _first paragraph_). The system proposed in the text is
+substantially the Egyptian method, the Nile dikes having been
+constructed rather to retain than to exclude the water. The waters of
+rivers which flow down planes of gentle inclination, deposit in their
+inundations the largest proportion of their sediment as soon as, by
+overflowing their banks, they escape from the swift current of the
+channel, and consequently the immediate banks of such rivers become
+higher than the grounds lying farther from the stream. In the
+"intervals," or "bottoms," of the great North American rivers, the
+alluvial banks are elevated and dry, the flats more remote from the
+river lower and swampy. This is generally observable in Egypt, though
+less so than in the valley of the Mississippi, where, below Cape
+Girardeau, the alluvial banks constitute natural glacis descending as
+you recede from the river, at an average of seven feet in the first
+mile.--HUMPHREYS AND ABBOT'S _Report_, pp. 96, 97.
+
+The Egyptian crossdikes, by retaining the water of the inundations,
+compel it to let fall its remaining slime, and hence the elevation of
+the remoter land goes on at a rate not very much slower than that of the
+immediate banks. Probably transverse embankments would produce the same
+effect in the Mississippi valley. In the great floods of this river, it
+is observed that, at a certain distance from the channel, the bottoms,
+though lower than the banks, are flooded to a less depth. See cross
+sections in Plate IV. of Humphreys and Abbot's Report. This apparently
+anomalous fact is due, I suppose, to the greater swiftness of the
+current of the overflowing water in the low grounds, which are often
+drained through the channels of rivers whose beds lie at a lower level
+than that of the Mississippi, or by the bayous which are so
+characteristic a feature of the geography of that valley. A judicious
+use of dikes would probably convert the swamps of the lower Mississippi
+valley into a region like Egypt.
+
+No. 51 (_second note_). The mean discharge of the Mississippi is 675,000
+cubic feet per second, and, accordingly, that river contributes to the
+sea about eleven times as much water as the Po, and more than sis and
+a half times as much as the Nile. The discharge of the Mississippi
+is estimated at one-fourth of the precipitation in its basin,
+certainly a very large proportion, when we consider the rapidity of
+evaporation in many parts of the basin, and the probable loss by
+infiltration.--HUMPHREYS AND ABBOT'S _Report_, p. 93.
+
+No. 52 (page 423, _first paragraph_). Artificially directed currents of
+water have been advantageously used in civil engineering for displacing
+and transporting large quantities of earth, and there is no doubt that
+this agency might be profitably employed to a far greater extent than
+has yet been attempted. Some of the hydraulic works in California for
+washing down masses of auriferous earth are on a scale stupenduous
+enough to produce really important topographical changes.
+
+No. 53 (page 435, _first note_). I have lately been informed by a
+resident of the Ionian Islands, who is familiar with this phenomenon,
+that the sea flows uninterruptedly into the sub-insular cavities, at all
+stages of the tide.
+
+No. 54 (page 438, _note_). It is observed in Cornwall that deep mines
+are freer from water in artificially well-drained, than in undrained
+agricultural districts.--ESQUIROS, _Revue des Deux Mondes_, Nov. 15,
+1863, p. 430.
+
+No. 55 (page 441). See, on the Artesian wells of the Sahara, and
+especially on the throwing up of living fish by them, an article
+entitled, _Le Sahara_, etc., by Charles Martins, in the _Revue des Deux
+Mondes_ for August 1, 1864, pp. 618, 619.
+
+No. 56 (page 444, _first note_). From the article in the _Rev. des Deux
+Mondes_, referred to in the preceding note, it appears that the wells
+discovered by Ayme were truly artesian. They were bored in rock, and
+provided at the outlet with a pear-shaped valve of stone, by which the
+orifice could be closed or opened at pleasure.
+
+No. 57 (page 447, _second note_). Hull ingeniously suggests that,
+besides other changes, fine sand intermixed with or deposited above a
+coarser stratum, as well as the minute particles resulting from the
+disintegration of the latter, may be carried by rain in the case of
+dunes, or by the ordinary action of sea water in that of subaqueous
+sandbanks, down through the interstices in the coarser layer, and thus
+the relative position of fine sand and gravel may be more or less
+changed.--_Oorsprong der Hollandsche Duinen_, p. 103.
+
+No. 58 (page 479). It appears from Laurent, that marine shells, of
+extant species, are found in the sands of the Sahara, far from the sea,
+and even at considerable depths below the surface.--_Memoires sur le
+Sahara Oriental_, p. 62.
+
+This observation has been confirmed by late travellers, and is an
+important link in the chain of evidence which tends to prove that the
+upheaval of the Libyan desert is of comparatively recent date.
+
+No. 59 (p. 480). "At New Quay [in England] the dune sands are converted
+to stone by an oxyde of iron held in solution by the water which
+pervades them. This stone, which is formed, so to speak, under our eye,
+has been found solid enough to be employed for building."--ESQUIROS,
+_L'Angleterre et la vie Anglaise_, _Revue des Deux Mondes_, 1 March,
+1864, pp. 44, 45.
+
+No. 60 (page 496, _first paragraph_). In Ditmarsh, the breaking of the
+surface by the man[oe]uvering of a corps of cavalry let loose a
+sand-drift which did serious injury before it was subdued.--KOHL,
+_Inseln u. Marschen._ etc., III. p. 282.
+
+Similar cases have occurred in Eastern Massachusetts, from equally
+slight causes.--See THOREAU, _A Week on the Concord and Merrimack
+Rivers_, pp. 151-208.
+
+No. 61 (page 497, _last note_). A more probable explanation of the fact
+stated in the note is suggested by Elisee Reclus, in an article
+entitled, _Le Littoral de la France_, in the _Revue des Deux Mondes_ for
+Sept. 1, 1864, pp. 193, 194. This able writer believes such pools to be
+the remains of ancient maritime bays, which have been cut off from the
+ocean by gradually accumulated sand banks raised by the waves and winds
+to the character of dunes.
+
+No. 62 (page 506, _note_). The statement in the note is confirmed by
+Olmsted: "There is not a sufficient demand for rosin, except of the
+first qualities, to make it worth transporting from the inland
+distilleries; it is ordinarily, therefore, conducted off to a little
+distance, in a wooden trough, and allowed to flow from it to waste upon
+the ground. At the first distillery I visited, which had been in
+operation but one year, there lay a congealed pool of rosin, estimated
+to contain over three thousand barrels."--_A Journey in the Seaboard
+Slave States_, 1863, p. 345.
+
+No. 63 (page 507). In an article on the dunes of Europe, in Vol. 29
+(1864) of _Aus der Natur_, p. 590, the dunes are estimated to cover, on
+the islands and coasts of Schleswig Holstein, in Northwest Germany,
+Denmark, Holland, and France, one hundred and eighty-one German, or
+nearly four thousand English square miles; in Scotland, about ten
+German, or two hundred and ten English miles; in Ireland, twenty German,
+or four hundred and twenty English miles; and in England, one hundred
+and twenty German, or more than twenty-five hundred English miles.
+
+No. 64 (page 512, _last paragraph_). For a brilliant account of the
+improvement of the Landes, see Edmond About, _Le Progres_, Chap, VII.
+
+In the memoir referred to in _Appendix_, No. 48, _ante_, Duponchel
+proposes the construction of artificial torrents to grind calcareous
+rock to slime by rolling and attrition in its bed, and, at the same
+time, the washing down of an argillaceous deposit which is to be mixed
+with the calcareous slime and distributed over the Landes by
+watercourses constructed for the purpose. By this means, he supposes
+that a highly fertile soil could be formed on the surface, which would
+also be so raised by the process as to admit of freer drainage. That
+nothing may be wanting to recommend this project, Duponchel suggests
+that, as some of the rivers of Western France are auriferous, it is
+probable that gold enough may be collected from the washings to reduce
+the cost of the operations materially.
+
+No. 65 (page 528, _first paragraph_). The opening of a channel across
+Cape Cod would have, though perhaps to a smaller extent, the same
+effects in interchanging the animal life of the southern and northern
+shores of the isthmus, as in the case of the Suez canal; for although
+the breadth of Cape Cod does not anywhere exceed twenty miles, and is in
+some places reduced to one, it appears from the official reports on the
+Natural History of Massachusetts, that the population of the opposite
+waters differs widely in species.
+
+Not having the original documents at hand, I quote an extract from the
+_Report on the Invertebrate Animals of Mass._, given by Thoreau,
+_Excursions_, p. 69: "The distribution of the marine shells is well
+worthy of notice as a geological fact. Cape Cod, the right arm of the
+Commonwealth, reaches out into the ocean some fifty or sixty miles. It
+is nowhere many miles wide; but this narrow point of land has hitherto
+proved a barrier to the migration of many species of mollusca. Several
+genera and numerous species, which are separated by the intervention of
+only a few miles of land, are effectually prevented from mingling by the
+Cape, and do not pass from one side to the other * * * * Of the one
+hundred and ninety-seven marine species, eighty-three do not pass to the
+south shore, and fifty are not found on the north shore of the Cape."
+
+Probably the distribution of the species of mollusks is affected by
+unknown local conditions, and therefore an open canal across the Cape
+might not make every species that inhabits the waters on one side
+common to those of the other; but there can be no doubt that there would
+be a considerable migration in both directions.
+
+The fact stated in the report may suggest an important caution in
+drawing conclusions upon the relative age of formations from the
+character of their fossils. Had a geological movement or movements
+upheaved to different levels the bottoms of waters thus separated by a
+narrow isthmus, and dislocated the connection between those bottoms,
+naturalists, in after ages, reasoning from the character of the fossil
+faunas, might have assigned them to different, and perhaps very widely
+distant, periods.
+
+No. 66 (page 548, _first paragraph_). To the geological effects of the
+thickening of the earth's crust in the Bay of Bengal, are to be added
+those of thinning it on the highlands where the Ganges rises. The same
+action may, as a learned friend suggests to me, even have a cosmical
+influence. The great rivers of the earth, taken as a whole, transport
+sediment from the polar regions in an equatorial direction, and hence
+tend to increase the equatorial diameter, and at the same time, by their
+inequality of action, to a continual displacement of the centre of
+gravity, of the earth. The motion of the globe and of all bodies
+affected by its attraction, is modified by every change of its form, and
+in this case we are not authorized to say that such effects are in any
+way compensated.
+
+
+
+
+INDEX
+
+
+ Abbeys of St. Germain and St. Denis, revenues of, 6.
+
+ Adirondack forest, 235;
+ lakes of, 357.
+
+ Ailanthus glandulosa, 515.
+
+ Akaba, gulf of, infiltration of fresh water in, 440.
+
+ Albano, lake of, artificial lowering of, 353.
+
+ Algeria, deserts of, artesian wells in, 443;
+ sand dunes of, 463;
+ consolidated dunes, 480.
+
+ Alpaca, South American, 83.
+
+ Amazon, Indians of, 11.
+
+ Ameland, island of, 499.
+
+ America, North, primitive physical condition of, 27, 43;
+ forests of, 28;
+ possibility of noting its physical changes, 52;
+ by scientific observation, 53;
+ forest trees of, 274;
+ sand dunes of, 469;
+ proposed changes in hydrography of, 532.
+
+ Animal life, sympathy of ruder races with, 39;
+ instinct, fallibility of, 40;
+ hostility of civilized man to inferior forms of, 121.
+
+ Animals, wild, action of on vegetation, 78.
+
+ Aphis, the European, 104.
+
+ Apennines, effects of felling the woods on, 150, 152.
+
+ Appian way, the, 542.
+
+ Aqueducts, geographical and climatic effects of, 358.
+
+ Arabia Petraea, surface drainage of, 440;
+ sandstone of, 452;
+ sands and petrified wood of, 455;
+ wadies of, 538.
+
+ Aragua, valley of, Venezuela, 202.
+
+ Ararat, Mt., phenomenon of vegetation on, 287.
+
+ Ardeche, l', department of, 152;
+ destruction of forests in, 389.
+
+ -- river and basin, floods of, 386;
+ supply of water to the Rhone, 388, 398;
+ violence of inundations of, 388;
+ damage done by, 390;
+ effect on river beds, 391;
+ force of its affluents, 392.
+
+ Argostoli, Cephalonia, millstreams of, 434.
+
+ Armenia, ancient irrigation of, 366.
+
+ Arno, the river, deposits of, 414;
+ upper course of in the Val di Chiana, 417, 420.
+
+ Artesian wells, their sources, 441;
+ usual objects, 442;
+ occasional effects, 442;
+ employment in the Algerian desert, 443;
+ by the French Government, 444;
+ success and probable results of, 445;
+ known to the ancients, 443;
+ depth of, 444.
+
+ Arundo arenaria, 501.
+
+ Ascension, island of, 205.
+
+ Auk, the wingless, extirpation of, 95.
+
+ Australia a field of physical observation, 51.
+
+ Avalanches, Alpine, various causes of, 266;
+ by felling trees, 270.
+
+ Azoff, sea of, proposed changes, 531.
+
+
+ Babinet, plan for artificial springs, by, 448.
+
+ Baikal Lake, the fish of, 117.
+
+ Baltic Sea, sand dunes of, 467.
+
+ Barcelonette, valley of, former fertility, 243;
+ present degradation of, 244.
+
+ Bavaria, scarcity of fuel in, 299.
+
+ Bear, the mythical character of, 40.
+
+ Beaver, the, agency in forming bogs, 31;
+ cause of its increased numbers, 84.
+
+ Bee, the honey, products of, 105;
+ introduction in United States, 106.
+
+ Belgium, effect of plantations in, 152;
+ Campine of, 513.
+
+ Ben Gasi, district of, rock formation in, 537.
+
+ Bergamo, change of climate in the valley of, 151.
+
+ Bibliographical list of authorities, vii.
+
+ Birch tree (black and yellow), produce of, 171.
+
+ Birds, number of, in United States, 86;
+ the turkey, dove, pigeon, 87;
+ as sowers and consumers of seeds, 87;
+ as destroyers of insects, 89;
+ injurious extirpation of, 90;
+ wanton destruction of, 92;
+ weakness of, 93;
+ instinct of migratory, 94;
+ extinction of species, 95;
+ commercial value of, 97;
+ introduction of species, 98.
+
+ Bison, the American, 78;
+ number and migrations of, 81, 83;
+ domesticated, 135.
+
+ Blackbird, the proscription of, 91.
+
+ Bogs, formation and nomenclature of, 29-32;
+ of New England, 29;
+ repositories of fuel, 30.
+
+ Bremontier, system of dune plantations of, 503;
+ a benefactor to his race, 515.
+
+ Breton, Cap, dune vineyards of, 508.
+
+ Busbequius' letters, 64.
+
+
+ Camel, the, transfer and migrations of, 83;
+ injurious to vegetation, 132.
+
+ Campine of Belgium, 513.
+
+ Canada thistle, the, 68.
+
+ Canals, geographic and climatic effects of, 359;
+ injurious effects of Tuscan, 359;
+ projected, Suez, 519;
+ Isthmus of Darien, 522;
+ to the Dead Sea, 524;
+ maritime, in Greece, 526;
+ Saros, 527;
+ Cape Cod, 528;
+ the Don and the Volga, 531;
+ Lake Erie and the Genesee, 532;
+ Lake Michigan and the Mississippi, 533.
+
+ Cape Cod, sand dunes of, 487;
+ legislative protection of, 502;
+ vegetation of, 503;
+ projected canal through, 528.
+
+ Cappercailzie, the, extinction of, in Britain, 96.
+
+ Carniola, caves of, 434.
+
+ Caspian Sea, proposed changes in its basin, 531.
+
+ Catania, lava streams of, 544.
+
+ Catavothra of Greece, 536.
+
+ Cevennes, effects of clearing the, 153.
+
+ Champlain, lake, dates of its congelation, 163.
+
+ Cherbourg, breakwater of, 46, 332.
+
+ Chiana, Val di, description and character of, 417-420;
+ plans for its restoration, 420;
+ artificial drainage of, attempted, 421;
+ successfully executed, 423.
+
+ Clergy, mediaeval, their character, 282.
+
+ Climatic change, discussions of, 9;
+ how tested, 20;
+ causes producing, in New England, Africa, Arabia Petraea, 20-22;
+ man's action on, difficult to ascertain, 51;
+ deterioration, 71.
+
+ Coal mines, combustion of, 546.
+
+ Coal, sea, early use of, for fuel, 222;
+ increased use of, in Paris, 295.
+
+ Coast line, change of, from natural causes, 331;
+ subject to human guidance, 332.
+
+ Cochineal insect transferred to Spain, 105.
+
+ Cochituate Aqueduct, Boston, 103.
+
+ Col Isoard, valley of, devastated, 242.
+
+ Commerce, modern, on what dependent, 60.
+
+ Como, lake of, proposed lowering of, 358.
+
+ Constance, lake of, 534.
+
+ Cork-oak tree, yield of, 311.
+
+ Corporations, social and political, influence of, 54.
+
+ Cosmical influences, 13.
+
+ Cotton, early cultivation of, 61;
+ can be raised by white labor, 381.
+
+ Crawley Sparrow Club, 90.
+
+ Currents, sea, strength of, 456;
+ in the Bosphorus, 457.
+
+ Cuyahoga river, 208.
+
+ Cypress tree, its beauty, 314.
+
+
+ Darien, Isthmus of, proposed canal across, 522;
+ conjectural effects of, 523.
+
+ Dead Sea, projected canals to, 524;
+ possible results of, 525.
+
+ Deer, numbers of, in United States; 82;
+ tame, injurious to trees, 130.
+
+ Denmark, peat mosses of, 22;
+ dunes of, 497;
+ extent and movement of, 498;
+ legislative protection of, 501, 504.
+
+ Desert, the, richness of local color, 445;
+ mirage in, 446.
+
+ Des Plaines river, 533.
+
+ Despotism a cause of physical decay, 5.
+
+ Dikes, recovery of land by, in the Netherlands, 335;
+ early usage and immense extent of, 336;
+ encouraged by the Spaniards, 337;
+ details of their construction and effect on the land
+ gained, 340-345;
+ in Egypt, 413.
+
+ Dinornis, or moa, recent extirpation of, in New Zealand, 95.
+
+ Dodo, the, extirpation of, 95.
+
+ Domestic animals, action of, on vegetation, 79;
+ origin and transfer of, 82;
+ injurious to the forest growth, 130.
+
+ Don river, proposed diversion of, 531.
+
+ Draining a geographical element, 360;
+ superficial, its necessity in forest lands, 363;
+ effect on temperature, 364;
+ underground, _ib._;
+ extensive use of, in England, 362;
+ affects the atmosphere, 364;
+ disturbs the equilibrium of river supply, 365;
+ by boring, 362;
+ in France, &c., 362;
+ Paris, 363.
+
+ Drance, Switzerland, glacier lake of, 403.
+
+ Dry land and water, relative extent of, 178.
+
+ Dwight, Dr., Travels in the United States, characterized, 52.
+
+
+ Earth, fertile, below the rock, 537;
+ transported to cover rocky surfaces, 537.
+
+ Earthquakes, effects of, 542;
+ causes and possible prevention of, 543;
+ of Lisbon, 544.
+
+ Earthworm, utility of, in agriculture, 100;
+ multiplication of, in New England, 101.
+
+ Egypt, catacombs, 70;
+ papyrus or water lily, 70;
+ poisonous snakes of, 112;
+ supposed increase of rain in, 190;
+ productiveness of, 230;
+ necessity and extent of irrigation in, 368, 373;
+ cultivated soil of, 372, 374;
+ population of, 374;
+ amount of water used for irrigation, 380;
+ saline deposits, 382;
+ artificial river courses of, 402;
+ cultivated area of, 412;
+ sands of, 458;
+ their prevalence and extent, 459;
+ source of, 461;
+ action on the Delta and cultivated land, 462;
+ effect of the diversion of the Nile on, 529;
+ refuse heaps near Cairo, 541.
+
+ Eland, the, preserved in Prussia, 86.
+
+ Elm, the Washington, Cambridge, 146.
+
+ Elsineur, artificial formation in harbor of, 539.
+
+ England, forest economy of, 221;
+ large extent of ornamental plantations, 222;
+ Forests of, described by Caesar, 222;
+ private enterprise in sylviculture, 292;
+ sand dunes of, 507.
+
+ Enguerrand de Coucy, cruelty of, 281.
+
+ Erie Canal, the, influence on the fauna and flora of its region, 116;
+ lake, depth and level of, 532;
+ proposed canal from, 532.
+
+ Espy's theories of artificial rain, 547.
+
+ Etna, volcanic lava and dust, 131.
+
+ Euphrates, sand plains in the valley of, 511.
+
+ Eye, cultivation of the, 11;
+ control of the limbs by, 12;
+ trained by the study of physical geography, 12.
+
+
+ Feudalism, pernicious influence of, 6.
+
+ Fir tree, the, its products, 311.
+
+ Fire weed, in burnt forests of the United States, 287.
+
+ Fish, destruction of, by man, 112, 114, 120, 122;
+ voracity of, 114;
+ introduction and breeding of foreign, 116;
+ naturalization of, 117;
+ inferiority of the artificially fattened, 121.
+
+ Fish, shell, extensive remains of, in United States, 117;
+ of Indian origin, 128.
+
+ Fish ponds of Catholic countries, 426.
+
+ Fontainebleau, forest of, 34, 130;
+ poaching in, 284;
+ its renovation, 316;
+ soil of, 513.
+
+ Food, ancient arts of preservation of, 18.
+
+ Forest, the, influence of, on the humidity of air, 162;
+ do. of earth, 165;
+ as organic, 166;
+ balance of conflicting influences in, 176;
+ influence on temperature, 178;
+ on precipitation, 181, 196;
+ in South America, 184;
+ the Canary Islands and Asia Minor, 185;
+ Peru, 188;
+ Palestine, Southern France, Scotland and Egypt, 189;
+ influence of, on humidity of soil, 196;
+ on springs, 197;
+ in Venezuela, 202;
+ New Granada, 204;
+ Switzerland and France, 205, 208;
+ United States, 207;
+ in winter, 210;
+ general consequences of its destruction, 214;
+ on the earth, springs, rivers, 215;
+ literature of, in France, 217;
+ Germany, 218;
+ Italy, 218;
+ England, 221;
+ influence of, on inundations, 223;
+ in North America, 225;
+ disputed effects of, in Europe, 228;
+ principal causes of its destruction, 270;
+ in British America, 271;
+ in Europe, 279;
+ royal forests, 280;
+ effects of the Revolution on, in France, 284;
+ utility of, for the preservation of smaller plants, 286, 290;
+ do. of birds, 291;
+ economic utility of, and necessity for its restoration, 292;
+ extent of, in Europe, 296;
+ proportion in different countries of, 300;
+ of the United States and Canada, 300;
+ economy of, 303;
+ management of, in France, 304;
+ European forests, all of artificial growth, 305;
+ artificial and natural, their respective advantages, 307;
+ American do., their peculiar characteristics, 313;
+ economic action of cattle on, 325;
+ duty of preserving, 327;
+ average revenue from, 327;
+ regulated by laws in France, 395.
+ See _Trees_, _Woods_.
+
+ Forests of North America, balance of geographical elements in, 27;
+ agency of quadrupeds and insects in, 32;
+ injury to, by insects, 33;
+ meteorological importance of, 139.
+
+ Forest laws, mediaeval, character of, 217;
+ do. Jewish, 217;
+ severity of, in France and England, 280;
+ under Louis IX., 281;
+ of America, created by circumstances, 302.
+
+ France, forest literature and economy of, 217;
+ legislation on forests, 233;
+
+ -- Southeastern, former physical state of, 237;
+ altered condition of, 239;
+ royal forests of, and forest laws, 280;
+ extent of, in, 296;
+ ancient lakes of, 357;
+ inundations of 1856 in, 393;
+ remedies against inundations in, 395;
+ sand dunes of Western, 485;
+ encroachments of the sea on, 494.
+
+ French peasantry, described by La Bruyere, 6;
+ do. Arthur Young, 7;
+ of Chambord, 283.
+
+ Friesland, sand dunes of, 489.
+
+ Fucinus Lake (Lago di Celano), drainage of, by the Romans, 354;
+ moderns, 355.
+
+
+ Game Laws, effect on the numbers of birds in France, 91;
+ in England and Italy, 92;
+ severity of, in France, 283;
+ unable to stop poaching, 284.
+
+ Ganges, valley of the, 548.
+
+ Gascony, coast sands of, 453;
+ dunes of, 496;
+ extent and advance of, 497;
+ fixing and reclaiming of, 504;
+ Landes of, 511;
+ their reclamation, 512.
+
+ Geological influences, 13.
+
+ Geographers, new school of, 8.
+
+ Geographical influence of changes produced by man, 352.
+
+ Geography, modern, improved form of, 57.
+
+ German Ocean, sands of, 454, 457.
+
+ Germany, extent of forests in, 299.
+
+ Glacier lakes in Switzerland, 403.
+
+ Goat, the Cashmere or Thibet, 83.
+
+ Gold fish, the migration from China, 116.
+
+ Goldau, Switzerland, destruction of, 268.
+
+ Grape disease, its economic effect in France, Italy, Sicily, 72.
+
+ Grasshopper, the rapid increase in America, 291.
+
+ Gravedigger beetle, the, 107.
+
+ Greece,
+ proposed maritime canals in, through the Corinthian Isthmus, 526;
+ Mount Athos, 527;
+ subterranean waters of, 536.
+
+ Gulls, sea, habits of, 98.
+
+ Gulf stream, the, 523.
+
+ Gunpowder chiefly used for industrial purposes, 335.
+
+
+ Haarlem Lake, origin and extent of, 346, 347;
+ reasons for draining it, 348;
+ means employed, 349;
+ successful results, 350.
+
+ Hauran, the productions of, its soil, 74.
+
+ Heilbronn, springs at, 207.
+
+ Herring fishery, produce of, 120.
+
+ Hessian fly, introduction of in the United States, 104.
+
+ Honey bee, the wild, New England, legal usage, 302.
+
+ Humid air, movement of, 183.
+
+ Hunter in New England, exploits of, 82.
+
+
+ Ibex, the Alpine, 86.
+
+ India, saline efflorescence of its soil, 382;
+ natural connection of rivers in, 401.
+
+ Insects, injurious to vegetable life, 33;
+ utility of, 99;
+ agency in the fertilization of orchids, 102;
+ mass of their exuviae in South America, 102;
+ introduction of injurious species, 104, 106;
+ ravages of, 105;
+ tenacity of life in, 106;
+ the carnivorous, useful to man, 107;
+ destruction of, by fish, 108;
+ abundance of, in Northern Europe, 108;
+ destruction of, by birds, 109;
+ do. quadrupeds, 110;
+ do. reptiles, 110;
+ do not multiply in the forest, 291;
+ confine themselves to dead trees, 322.
+
+ Inundations, influence of the forest on, 223;
+ of the German Ocean, 334;
+ means for obviating, 384;
+ of 1856 in France, 393;
+ remedies against, 395;
+ legislative regulation of the woodlands in France for
+ prevention of, 396;
+ proposed basins of reception, 398;
+ do. in Peru and Spain, 400;
+ Rozet's plan for diminishing, 406.
+
+ Irrigation, remote date of in ancient nations, 366;
+ among Mexicans and Peruvians, 366;
+ its necessity in hot climates, 367;
+ in Europe, 367;
+ in Palestine, 368;
+ in Idumaea, 370;
+ Egypt, 371, 373;
+ quantity of water so applied, 376, 377;
+ extent of lands irrigated, 396;
+ effects of, 378;
+ on river supply, 380;
+ on human health, 381;
+ saline deposits from, in India and Egypt, 382;
+ effect of, on vegetable crops, 378;
+ on the soil, 379;
+ economic evils of, 379.
+
+ Islands, floating, in Holland and South America, 349, 351.
+
+ Ijssel river, Holland, 535.
+
+ Italy, effects of the denudation of its forests, 220;
+ political condition adverse to their preservation, 219;
+ beauty of its winter scenery, 314;
+ extent of irrigation in, 368;
+ atmospheric phenomena of Northern, 368.
+
+
+ Jupiter, satellites of, visible to the eye, 12.
+
+ Jutland, effects of felling the woods in, 150;
+ destruction of forests in, 279;
+ encroachments of the sea on, 491.
+
+
+ Kander river, Switzerland, artificial course of, 403.
+
+ Karst, the subterranean waters of, 536.
+
+ Kjoekkenmoeddinger in Denmark, 16;
+ their extent, 540.
+
+ Kohl, J. G., "the Herodotus of modern Europe," 340;
+ on dune sand, 475.
+
+
+ Labruguiere, commune of, 208.
+
+ Laestadius, account of the Swedish Laplanders, 96.
+
+ Lakes, draining of, by steam hydraulic engines, 346;
+ natural process of filling up by aquatic vegetation, 349;
+ lowering of, in ancient and modern times, 353;
+ in Italy, 354;
+ in Switzerland, 356;
+ inconvenient consequences of, 356;
+ mountain, their disappearance, 357.
+
+ Landscape beauty, insensibility of the ancients to, 2;
+ of the oasis and the desert, 445.
+
+ Lava currents, diversion of their course, 544;
+ from Vesuvius, phenomena of, 545;
+ heat emitted by, 545.
+
+ Life, balance of animal and vegetable, 103.
+
+ Liimfjord, the, irruption of the sea into, 491;
+ aquatic vegetation of, 492;
+ original state of, 519.
+
+ Lion, an inhabitant of Europe, 85.
+
+ Lisbon, earthquake of, 544.
+
+ Locust, the, does not multiply in woods, 296;
+ tree and insect, 32.
+
+ Lombardy, statistics of irrigation in, 376.
+
+ Louis IX., of France, clemency of, 282.
+
+ Lower Alps, department of, ravages of torrents in, 246.
+
+ Lumber trade of Quebec, 271;
+ of United States, 1850-'60, 301.
+
+ Lungern, lake of, lowering of, 356.
+
+
+ Madagascar, gigantic bird of, 96;
+ the ai-ai of, 110.
+
+ Madder, early cultivation of, in Europe, 20.
+
+ Madeira, named from its forests, 129.
+
+ Maize, early cultivation of, law of its acclimation, 19;
+ native country of, 73.
+
+ Malta, transported soil of, 538;
+ salt works at, 540.
+
+ Man, reaction of, on nature, 8;
+ insufficiency of data, 9;
+ geographical influence of, 13;
+ physical revolutions wrought by, 14;
+ unpremeditated results of conscious action, 15;
+ ancient relics of, in old geological formations, 16;
+ mechanical effects of, on the earth's surface, 25;
+ destructiveness of, 35;
+ in animal life and inorganic nature, 36-39;
+ character of his action compared with that of brutes, 42;
+ subversive of the balance of nature, 43;
+ sometimes exercised for good, 44;
+ present limits to, 45;
+ transfer of vegetable life by, 59;
+ remains of, 76;
+ contemporary with the mammoth, 77;
+ agency in the extermination of birds, 96;
+ do. introduction of species, 98;
+ increase of insect life, 104;
+ introduction of new forms of do. by, 105;
+ destruction of fish by, 112, 120, 122;
+ extirpation of aquatic animals by, 119;
+ possible control of minute organisms, 125;
+ his first physical conquest, 135;
+ his action on land and the waters, 330;
+ possible geographical changes by, 517;
+ incidental effects of his action, 539;
+ illimitable and ever enduring do., 548.
+
+ Maremme of Tuscany, ancient and mediaeval state of, 425;
+ extent of, 427;
+ inhabitants, 428;
+ improvement of, 429;
+ sedimentary deposits of, 425, 430.
+
+ Marine isthmuses, cutting of, 517;
+ its difficulties, 518;
+ sometimes done by nature, 519.
+
+ Marmato in Popayan, 205.
+
+ Marshes, climatic effects of draining, 358;
+ insalubrity of mixture of fresh and salt water in, 417.
+
+ Mechanic arts, illustration of their mutual interdependence, 307.
+
+ Medanos of the South American desert, 482.
+
+ Mediterranean Sea, tides of, 425;
+ sand dunes of, 467;
+ poor in organic life, 520.
+
+ Mella, the river, Italy, 248.
+
+ Meteorology, uncertainty and late rise of, 16, 22;
+ varying nomenclature of, 23;
+ precipitation and evaporation, 24.
+
+ Michigan, lake, sand dunes of, 467;
+ originally wooded, 487;
+ proposed diversion of its waters, 532.
+
+ Mining excavations, effects of, 545.
+
+ Minute organisms, their offices, 123;
+ universal diffusion and products of, 124, 127;
+ possible control of their agency by man, 125;
+ the coral insect, 125;
+ the diatomaceae, 126.
+
+ Miramichi, great fire of, 28.
+
+ Mistral in France, 153.
+
+ Mississippi river, "cut offs" and their effect, 415;
+ precipitation in the valley of, 436;
+ projected canal to, 533.
+
+ Mountain slides, their cause, 265, 268;
+ their frequency in the Alps, 267.
+
+ Mountainous countries, their liability to physical degradation, 50.
+
+ Monte Testaccio, Rome, 541.
+
+ Moose deer, the American, rapid multiplication of, 130.
+
+ Mushrooms, poisonous, how to render harmless, 286.
+
+
+ Natural forces, accumulation of, 46;
+ resistance to, 542.
+
+ Nature, man's reaction on, 8;
+ observation of, 10;
+ stability of, 27, 34;
+ restoration of disturbed harmonies of, 35;
+ nothing small in, 548.
+
+ Naturalists, enthusiasm of, 99.
+
+ Netherlands, ancient inundations of, 334;
+ recovery of land by diking, 334;
+ the practice derived from the Romans, 335;
+ extent of land gained from the sea, 336;
+ do. lost by incursions of do., 337;
+ character of lands gained, 338;
+ natural process of recovery, 339;
+ grandeur of the dike system of, 340;
+ method of their construction in, 341;
+ modes of protection, 343;
+ various uses of, 343;
+ effect on the level of the land, 344;
+ drainage of do., 345;
+ primitive condition of, 351;
+ effects on the social, moral, and economic interests of the
+ people of, 351;
+ sand dunes of, 486;
+ encroachments of the sea on, 494;
+ artificial dunes in, 499;
+ protection of dunes in, 500;
+ removal of do., 509.
+
+ Nile, the river, valley of, 374;
+ its ancient state, 375;
+ inundations of, 385;
+ water delivery of, 387;
+ artificial mouths of, 402;
+ consequences of diking, 410, 413;
+ richness of its deposits, 411;
+ extent of do., 412;
+ mud banks caused by its deposits, 433;
+ sand dunes at its mouths, 468;
+ conduits for irrigation, 521;
+ proposed diversion of, 528;
+ not impossible, 529;
+ effects of, 530;
+ ceramic banks of, 541.
+
+ Northmen in New England, 60.
+
+ Nubians, Nile boats of the, 17.
+
+ Numbers, the frequent error in too definite statements of, 260;
+ oriental and Italian usage of, 261.
+
+
+ Oak, the English, early uses in the arts, 223;
+ "openings" of North America, 136.
+
+ Ohio, mounds of, 18;
+ remains of a primitive people in, 135, 138;
+ apple trees of, 22.
+
+ Old World, former populousness of, 4;
+ physical decay of, 3;
+ present desolation of, 5;
+ its causes, 5;
+ ancient climate of, 19;
+ physical restoration of, 47.
+
+ Olive tree, the wild, 74;
+ importance of, 312.
+
+ Orange tree known to the ancients, 64;
+ the wild, 74.
+
+ Orchids, fertilization of, by insects, 102.
+
+ Organic life embraced in modern geography, 57;
+ its geological agency, 75;
+ geographical importance of, 7;
+ bones and relics of, human and animal, 76.
+
+ Ostrich, the, diminution of its numbers, 97.
+
+ Ottaquechee river, Vermont, transporting power of, 253.
+
+ Otter, the American, voracity of, 120.
+
+ Oxen, agricultural uses of, in United States, 80.
+
+ Oyster, the, transplantation of, 118.
+
+
+ Palestine, ancient terrace culture and irrigation of, 369;
+ disastrous effects of its neglect, 370.
+
+ Palissy, Bernard, character of, 218;
+ plan for artificial springs, 447.
+
+ Paragrandini of Lombardy, 141.
+
+ Paramelle, the Abbe, on fountains, 437.
+
+ Peat beds, accidental burning of, 546;
+ -- mosses of Denmark, 32.
+
+ Pecora, river of the Maremma, its deposits, 425.
+
+ Peru, ancient progress in the arts, 366;
+ basins of reception in, 400.
+
+ Petra, in Idumaea, ancient irrigation at, 370.
+
+ Phosphorescence of the sea unknown to the ancients, 114.
+
+ Physical decay of the earth's surface, 3;
+ its causes, 5;
+ arrest of, in new countries, 48;
+ forms and formations predisposing to, 49.
+
+ Physical geography, study of recommended, 12;
+ restoration of the earth, 8;
+ importance and possibility of, 26;
+ of disturbed harmonies, 35;
+ of the Old World, 47.
+
+ Pine, the American, former ordinary dimensions of, 275;
+ how affected by the accidents of its growth, 306;
+ the maritime, on dune sands in France, 506;
+ the pitch, hardihood of, 273;
+ umbrella, the, most elegant of trees, 309, 313;
+ the white, rapidity of its growth, 274.
+
+ Pinus cembra of Switzerland, 309.
+
+ Pisciculture, its valuable results, 118.
+
+ Plants, cultivated, uncertain identity of ancient and modern, 19;
+ do. of wild and domestic species, 73;
+ changes of habit by domestication, 19;
+ geographical influence of, 58;
+ foreign, grown in United States, 61;
+ American, grown in Europe, 63;
+ modes of introduction, 64;
+ accidental do., 66;
+ power of accommodation of, 65;
+ how affected by transfer, 68;
+ tenacity of life in wild species, 69;
+ extirpation of, 70;
+ domestic origin of, 72;
+ species employed for protection of sand dunes, 500.
+
+ Pliny, the elder, theory of springs, 198, 216.
+
+ Po, river, ancient state of its basin, 255;
+ modern changes, 256;
+ its floods, tributaries, and deposits, 256-261, 405;
+ embankments of, 385, 404;
+ sediment of, 410;
+ age and consequences of its embankments, 411;
+ mean delivery of, 412;
+ _salti_ of, 415.
+
+ Poland, sand plains of, 514.
+
+ Poplar, the Lombardy, 68;
+ characterized, 313.
+
+ Potato, native country of, 73.
+
+ Prairies, conjectural origin of, 134.
+
+ Provence, physical structure of, 237;
+ ancient state of, 238;
+ destructive action of torrents on, 236;
+ Alps of, 245.
+
+ Prussia, sand dunes of, 485;
+ drifting of, 498;
+ measures for reclaiming of, 505.
+
+
+ Quadrupeds, number in United States, 79;
+ extirpation of, 84.
+
+ Quebec, high tides of, 271;
+ lumber trade of, 272.
+
+
+ Railways, scientific uses of, 53.
+
+ Rain water, its absorption and infiltration, 438, 439;
+ economizing its precipitation, 449.
+
+ Ravenna, cathedral of, 60;
+ pine woods of, 150.
+
+ Red Sea, richness of, in organic life, 320;
+ diversion of the Nile to, its effects, 530.
+
+ Reindeer, the, 83.
+
+ Reservoirs, geographic and climatic effects of, 258.
+
+ Reventlov's organization of dune economy in Denmark, 504;
+ a benefactor to his race, 515.
+
+ Rhine, river, proposed diversion of, 533.
+
+ Rice, cultivation of, 381.
+
+ Rivers, transporting power of, 252;
+ in Vermont, 253;
+ their origin, 262;
+ injury to their banks by lumbermen, 277;
+ conditions of their rise and fall, 278;
+ mutual action of rivers and valleys, 408;
+ effect of obstructions in, 409;
+ subterranean course of, 409;
+ confluences of, effect on the current below, 424;
+ sediment of, its extent, 547.
+
+ River beds, natural change of, 401;
+ artificial do. in Egypt, 402;
+ Italy and Switzerland, 403.
+
+ River deposits, 408;
+ of the Nile, 410;
+ the Po, 411;
+ the Tuscan rivers, 414.
+
+ River embankments, 384;
+ their use, 404;
+ disadvantages, 405;
+ transverse do., superiority of, 406;
+ effects of, 409.
+
+ River mouths, obstructions of, 430;
+ by sand banks, 431;
+ accelerated by man's influence, 432;
+ effect of tidal movements, 432.
+
+ Robin, the American, voracity of, 88.
+
+ Rock generally permeable by water, 265.
+
+ Roman empire, natural advantages of its territory, 1;
+ increased by intelligent labor, 2;
+ physical decay of, 3;
+ present desolation, 4;
+ caused by its despotism and oppression, 5.
+
+ Rozet's plan for diminishing inundations, 406.
+
+ Rude tribes, continuity of arts among, 17;
+ commerce of, 18;
+ relations to organic life, 39;
+ and to nature, 41.
+
+ Russia, diminution of forests in, 298;
+ effects of, on rivers and lakes, 299;
+ sand drifts of the steppes of, 514;
+ attempts to reclaim them, 515.
+
+
+ Sacramento City, California, effect of river dike at, 405.
+
+ Sand, its composition and origin, 452;
+ action of rivers, 453;
+ ancient deposits of, 454, 456;
+ amount of, carried to the Mediterranean, 455;
+ of Egypt, 458, 461;
+ movement of, by the wind, 459;
+ drifts of, from the sea, 461;
+ dangers of accumulation of, 463;
+ two forms of deposit, 463;
+ drifting of dune, 495.
+
+ Sand banks, aquatic, 468;
+ movement of, 469;
+ connect themselves with the coast, 490.
+
+ Sand dunes, how formed, 464;
+ utilization of, 465;
+ inland, of the South American desert, 482;
+ their peculiarities, 483;
+ age, character, and permanence of, 484;
+ naturally wooded, 486;
+ not noticed by ancient writers, 487;
+ management of, 488;
+ coast, sources of supply, 465;
+ law of their formation, 466, 471, 483;
+ of the Mediterranean, 467;
+ of Lake Michigan, 467;
+ of the Nile mouths, 468;
+ of America, 469;
+ of Western Europe, 470;
+ literature of, 471;
+ height of, 472;
+ humidity of, 473;
+ of Cape Cod, 487;
+ character of their sand, 474, 481;
+ concretion within, 476;
+ interior structure of, 477;
+ general form of, 478;
+ geological importance of, 479;
+ composition of sandstone, 481;
+ as barriers against the sea, 489;
+ in Western Europe, 490;
+ extent of, 507;
+ of Gascony, 496;
+ of Denmark, 497;
+ of Prussia, 497;
+ artificial formation of, in Holland, 499;
+ protection of, 500;
+ by vegetation, 501;
+ trees adapted to, 505;
+ removal of, 509.
+
+ Sand-dune vineyard of Cap Breton, 508.
+
+ Sand plains, mode of deposit, 464;
+ constituent parts, 464;
+ inland, of Europe, 509;
+ landes of Gascony, 511;
+ Belgium, 513;
+ Eastern Europe, 513;
+ advantages of reclaiming, 515;
+ private and public enterprise, 516.
+
+ Sand springs, 511.
+
+ Sandal wood extirpated in Juan Fernandez, 130.
+
+ Saros, projected canal of, 527.
+
+ Sawmills, action of their machinery more rapid by night, 278.
+
+ Schelk, the extirpation of, 85.
+
+ Schleswig-Holstein, encroachments of the sea on, 493.
+
+ Scientific observation, practical lessons of, 54-56.
+
+ Sea, the, exclusion of, by dikes, in Lincolnshire, 333;
+ encroachments of, 490;
+ coast, 491;
+ the Liimfjord, 491;
+ Schleswig-Holstein, 493;
+ Holland, 494;
+ France, 494.
+
+ Sea cow, Steller's, extirpation of, 119.
+
+ Seal, the, in Lake Champlain, 117;
+ voracity of, 120.
+
+ Seeds, vitality of, as preserved by the forest, 287, 289.
+
+ Seine river, ancient level of, 214;
+ affluents of, 435.
+
+ Ship building of the middle ages, Venice and Genoa, 218.
+
+ Siberia, ice ravine in, 158.
+
+ Sicily, stone weapons found in, 18;
+ sulphur mines of, 72;
+ olive oil crop of, 312.
+
+ Silkworm, introduction in South America, 105.
+
+ Sinai, Mt., rain torrent at, 441;
+ production of sand in peninsula of, 454;
+ garden of monastery at, 537.
+
+ Snakes, destructive to insects, 110;
+ tenacity of species, 111;
+ number of, in Palestine and Egypt, 111.
+
+ Snow, action of the woods on, 211;
+ experiments on, 212.
+
+ Soils, amount of thermoscopic action on various, 144;
+ mechanical effects of shaking in the Netherlands, 344;
+ effect of frost on, in United States, 344.
+
+ Solar heat, economic employment of, 47.
+
+ Solitary, the, extirpation of, 95.
+
+ Sound, transmission of, in still air, 165.
+
+ Springs, artificial, proposed by Palissy, 447;
+ by Babinet, 448.
+
+ Spain, neglect of forest culture in, 279.
+
+ Squirrel, the, destructiveness of, in forests, 34;
+ of Boston, 121.
+
+ St. Helena, flora of, 65;
+ destruction of its forests, 130.
+
+ Staffordshire, phenomena of vegetation in, 288.
+
+ Starlings, habits of, in Piedmont, 111.
+
+ Stork, the, geographical range of, 93;
+ anecdote of a, 99.
+
+ Subterranean waters, their origin, 434;
+ sources of supply, 435;
+ reservoirs and currents of, 438;
+ diffusion of, in the soil, 439;
+ importance, 440;
+ of the Karst, 535;
+ of Greece, 536.
+
+ Suez canal, the, danger from sand drifts, 461;
+ effect on the Mediterranean and Red Sea basins, 520.
+
+ Sugar cane, culture of, 62.
+
+ Sugar-maple tree, produce of, 169.
+
+ Summer dikes of Holland, 342.
+
+ Sunflowers, effect of plantations of, 154.
+
+ Swallow, the, popular superstitions respecting, 418.
+
+ Switzerland, ancient lacustrine habitations of, 16, 70, 83.
+
+ Sylt Island, sand dunes of, 474;
+ encroachments of the sea on, 493.
+
+ Sylviculture, best manuals of practice of, 304;
+ when and how profitable, 305;
+ its methods, 315;
+ the _taillis_ treatment, 315;
+ the _futaie_ do., 317;
+ beneficial effects of irrigation, 319;
+ exclusion of animals, 321;
+ removal of leaves, &c., 322;
+ topping and trimming, 324.
+
+
+ Taguataga Lake, Chili, 355.
+
+ Tea plant, the, cultivated in America, 62.
+
+ Temperature, general law of, 52.
+
+ Teredo, the general diffusion of, 107.
+
+ Termite, or white ant, ravages of, 107.
+
+ Teverone, cascade of, Tivoli, 402.
+
+ Timber, general superiority of cultivated, 305;
+ slow decay of, in forest, 322.
+
+ Tobacco an American plant, 68;
+ introduction in Hungary, 67.
+
+ Tocat, Asia Minor, oak woods of, 186.
+
+ Tomato, the, introduction to New England, 19.
+
+ Torricelli, successful plan for draining the Val di Chiana, 421.
+
+ Torrents, destructive action of, 231;
+ means of prevention, 233;
+ ravages of, in Southeastern France, 237;
+ Provence, 239;
+ Upper Alps, 240;
+ Lower Alps, 246;
+ action of, in elevating the beds of mainland streams, 249;
+ in excavating ravines, 250;
+ transporting power of, 251;
+ signs of, extinguished, 263;
+ crushing force of, 392.
+
+ Trees, as organisms, specific temperature of, 156;
+ moisture given out by, 158;
+ total influence on temperature, 159;
+ absorption of water by, 166;
+ flow of sap, 169;
+ absorption of moisture by foliage of, 172;
+ exhalation of do., 174;
+ consequent refrigeration, 175;
+ amount of ligneous products of, 173;
+ protection against avalanches afforded by, 269;
+ power of resisting the action of fire, 273;
+ American forest trees, 274;
+ their dimensions, 275;
+ change in relative proportions of height and diameter, 276;
+ comparative longevity of, 277;
+ European and American compared, 308;
+ species more numerous in America, 309;
+ Spenser's catalogue of, 308;
+ interchange of European and American species, 310;
+ species of Southern Europe and their extent, 312;
+ natural order of succession in, 323.
+ See _Forest_, _Woods_.
+
+ Trieste, proposed supply of water to, 536.
+
+ Trout, the American, 115, 117, 121.
+
+ Tuscany, rivers of, their deposits, 414;
+ physical restoration in, 416;
+ improvements in Val di Chiana, 417;
+ do. in the Maremma, 424.
+
+ Tyrolese rivers, elevation of their beds, 249.
+
+
+ Ubate, lakes of, New Granada, 204.
+
+ Undulation of water, 456.
+
+ United States, foreign plants grown in, 61;
+ weight of annual harvest in, 62;
+ number of quadrupeds in, 79;
+ of birds, 86;
+ effect of felling woods on its climate, 180;
+ forests of, 300;
+ instability of life in, 328.
+
+ Upper Alps, department of, ravages of torrents in, 240.
+
+ Urus, or auerochs, domesticated by man, 83;
+ extirpation of, 85.
+
+
+ Val de Lys, evidence of glacier action in, 252.
+
+ Vegetable life, transfer by man's action, 59.
+
+ Velino, cascade of, Tivoli, 402.
+
+ Vesuvius, vegetation on, 131;
+ eruption of February, 1851, 544.
+
+ Volcanic action, resistance to, 544;
+ matter, vegetation in, 131.
+
+ Volga river, proposed diversion of, 531.
+
+
+ Walcheren, formation of the island, 340.
+
+ Wallenstadt, lake of, 534.
+
+ Walnut tree, consumption of, for gun stocks, 296;
+ oil yielded by, 310.
+
+ Ward's cases for plants, 175.
+
+ Waste products, utilization of, 37.
+
+ Weeds common to Old and New World, 66;
+ extirpated in China, &c., 71.
+
+ Whale, the, food of, 113;
+ destruction of, 114.
+
+ Whale fishery, date of its commencement unknown, 112;
+ in the middle ages, 112;
+ American, 113.
+
+ Wheat, its asserted origin, 73;
+ introduction to America, 74.
+
+ Wild animals, number of, 84.
+
+ Wild organisms, vegetable and animal, tenacity of life in, 69.
+
+ Willow, the weeping, introduction in Europe, 64.
+
+ Wolf, increase of the, 84;
+ prevalence in forests of France, 296.
+
+ Wolf Spring, Soubey, 206.
+
+ Wood, increased demand for, 293;
+ ship building, railroads, &c., 294;
+ market price of, 294;
+ replaced by iron in the arts, 295;
+ means of increasing its durability, 295;
+ how affected by rapid growth, 306;
+ facilities for working, 307.
+
+ Woods, habitable earth originally covered by, 128;
+ conditions of their propagation, 131;
+ destructive agency of man and domestic animals, 132;
+ do not furnish food for man, 133;
+ first removal of, 134;
+ burning of, 136;
+ in Sweden and France, 137;
+ effect on the soil, 138;
+ destruction of, its effect, 139;
+ electrical influence of, 140;
+ chemical influence of, 142;
+ influence on temperature, 143;
+ absorbing and emitting surface of, 144;
+ in summer and winter, 147;
+ dead products of, 148;
+ as a shelter, 149;
+ in France, 149, 151;
+ New England, 149;
+ Italy and Jutland, 150;
+ as a protection against malaria, 154;
+ tend to mitigate extremes of temperature, 155.
+ See _Forest_, _Trees_.
+
+ Wood mosses and fungi, absorbent of moisture, 168.
+
+ Woodpecker, the, destroyer of insects, 109.
+
+
+ Yak, or Tartary ox, the, 83.
+
+ Yew tree, geographical range of, 70.
+
+
+ Zeeland, province, formation of, 339.
+
+ Zostera marina, 492.
+
+ Zuiderzee, proposed drainage of, 534;
+ means of, and geographical results, 535.
+
+
+THE END.
+
+
+ * * * * *
+
+
+
+FORSYTH'S "CICERO."
+
+A New Life of Cicero.
+
+BY WILLIAM FORSYTH, M. A., Q. C.
+
+With Twenty Illustrations. 2 vols. crown octavo. Printed on tinted and
+laid paper. Price, $5.00.
+
+
+The object of this work is to exhibit Cicero not merely as a Statesman
+and an Orator, but as he was at home in the relations of private life,
+as a Husband, a Father, a Brother, and a Friend. His letters are full of
+interesting details, which enable us to form a vivid idea of how the old
+Romans lived 2,000 years ago; and the Biography embraces not only a
+History of Events, as momentous as any in the annals of the world, but a
+large amount of Anecdote and Gossip, which amused the generation that
+witnessed the downfall of the Republic.
+
+The _London Athenaeuem_ says: "Mr. Forsyth has rightly aimed to set
+before us a portrait of Cicero in the modern style of biography,
+carefully gleaning from his extensive correspondence all those little
+traits of character and habit which marked his private and domestic
+life. These volumes form a very acceptable addition to the classic
+library. The style is that of a scholar and a man of taste."
+
+From the _Saturday Review_:--"Mr. Forsyth has discreetly told his story,
+evenly and pleasantly supplied it with apt illustrations from modern
+law, eloquence, and history, and brought Cicero as near to the present
+time as the differences of age and manners warrant. * * * These volumes
+we heartily recommend as both a useful and agreeable guide to the
+writings and character of one who was next in intellectual and political
+rank to the foremost man of all the world, at a period when there were
+many to dispute with him the triple crown of forensic, philosophic, and
+political composition."
+
+"A scholar without pedantry, and a Christian without cant, Mr. Forsyth
+seems to have seized with praiseworthy tact the precise attitude which
+it behoves a biographer to take when narrating the life, the personal
+life, of Cicero. Mr. Forsyth produces what we venture to say will become
+one of _the classics of English biographical literature_, and will be
+welcomed by readers of all ages and both sexes, of all professions and
+of no profession at all."--_London Quarterly._
+
+"This book is a valuable contribution to our Standard Literature. It is
+a work which will aid our progress towards the truth; it lifts a corner
+of the veil which has hung over the scenes and actors of times so full
+of ferment, and allows us to catch a glimpse of the stage upon which the
+great drama was played."--_North American Review._
+
+
+_Copies sent by mail, post paid, on receipt of price._
+
+
+
+
+LORD DERBY'S "HOMER."
+
+The Iliad of Homer.
+
+RENDERED INTO ENGLISH BLANK VERSE BY EDWARD, EARL OF DERBY.
+
+From the fifth London Edition.
+
+Two volumes, royal octavo, on tinted paper. Price $7.50 per vol.
+
+
+Extracts from Notices and Reviews from the English Quarterlies, &c.
+
+"The merits of Lord Derby's translation may be summed up in one word:
+"it is eminently attractive; it is instinct with life; it may be read
+with fervent interest; it is immeasurably nearer than Pope to the text
+of the original. * * * We think that Lord Derby's translation will not
+only be read, but read over and over again. * * * Lord Derby has given
+to England a version far more closely allied to the original, and
+superior to any that has yet been attempted in the blank verse of our
+language."--_Edinburgh Review, January 1865._
+
+"As often as we return from even the best of them (other translations)
+to the translation before us, we find ourselves in a purer atmosphere
+of taste. We find more spirit, more tact in avoiding either trivial
+or conceited phrases, and altogether a presence of merits, and an
+absence of defects which continues, as we read, to lengthen more
+and more the distance between Lord Derby and the foremost of his
+competitors."--_London Quarterly Review, January, 1865._
+
+"While the versification of Lord Derby is such as Pope himself would
+have admired, his Iliad is in all other essentials superior to that of
+his great rival. For the rest, if Pope is dethroned what remains? * * *
+It is the Iliad we would place in the hands of English readers as the
+truest counterpart of the original, the nearest existing approach to a
+reproduction of that original's matchless feature."--_Saturday Review._
+
+"Among those curiosities of literature which are also its treasures,
+Lord Derby's translation of Homer must occupy a very conspicuous
+place. * * * Lord Derby's work is, on the whole, more remarkable for
+the constancy of its excellence and the high level which it maintains
+throughout, than for its special bursts of eloquence. It is uniformly
+worthy of itself and its author."--_The Reader._
+
+"Whatever may be the ultimate fate of this poem--whether it take
+sufficient hold of the public mind to satisfy that demand for a
+translation of Homer which we have alluded to, and thus become a
+permanent classic of the language, or whether it give place to the still
+more perfect production of some yet unknown poet--it must equally be
+considered a splendid performance; and for the present we have no
+hesitation in saying that it is by far the best representation of
+Homer's Iliad in the English language."
+
+
+AMERICAN NOTICES.
+
+The _Publishers Circular_ says:--At the advanced age of sixty-five, the
+Earl of Derby, leader of the Tory party in England, has published a
+translation of Homer, in blank verse. Nearly all the London critics
+unite in declaring, with _The Times_, "that it is by far the best
+representation of Homer's 'Iliad' in the English language." His purpose
+was to produce a translation, and not a paraphrase--fairly and honestly
+giving the sense of every passage and of every line. Without doubt the
+greatest of all living British orators, he has now shown high poetic
+power as well as great scholarship.
+
+From the _New York World_:--"The reader of English, who seeks to know
+what Homer really was, and in what fashion he thought and felt and
+wrote, will owe to Lord Derby his first honest opportunity of doing so.
+The Earl's translation is devoid alike of pretension and of prettiness.
+It is animated in movement, simple and representative to phraseology,
+breezy in atmosphere, if we may so speak, and pervaded by a refinement
+of taste which is as far removed from daintiness or effeminacy as can
+well be imagined."
+
+
+_Copies sent by mail, post paid, on receipt of price._
+
+
+
+
+
+TRANSCRIBER'S NOTES:
+
+
+1. Passages in italics are surrounded by _underscores_.
+
+2. The original text includes Greek characters. For this text version
+these letters have been replaced with transliterations.
+
+3. Certain words use "oe" ligature in the original, indicated by [oe]
+and [OE].
+
+4. The letters with macron are represented within square braces with an
+equals sign preceding it. For example, letter a with macron is indicated
+by [=a].
+
+5. In this text version, some of the references to appendix notes within
+footnotes were incorrect which have been corrected. Also, errors found
+in page references within Appendix have been corrected.
+
+
+
+
+
+
+End of the Project Gutenberg EBook of Man and Nature, by George P. Marsh
+
+*** END OF THIS PROJECT GUTENBERG EBOOK MAN AND NATURE ***
+
+***** This file should be named 37957.txt or 37957.zip *****
+This and all associated files of various formats will be found in:
+ http://www.gutenberg.org/3/7/9/5/37957/
+
+Produced by Julia Miller and the Online Distributed
+Proofreading Team at http://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
+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.