Hakluyt
Society_, London, 1903.

[102] Volney, quoted in Malthus, Principles of Population, Chap. VII, p.
60. London, 1878.

[103] Genesis, Chap. XIII, 1-12.

[104] Herbert Spencer, Principles of Sociology, Vol. I. p. 457. New
York.

[105] Heinrich von Treitschke, _Politik_, Vol. I, pp. 202-204. Leipzig,
1897.

[106] E.C. Semple, American History and Its Geographic Conditions, pp.
206-207. Boston, 1903.

[107] Roscher, _Grundlagen des National-Oekonomik_, Book VI.
_Bevoelkerung_, p. 694, Note 5. Stuttgart, 1886.

[108] Edward John Payne, History of the New World Called America, Vol.
I, p. 303-313. Oxford and New York, 1892.

[109] Roscher, _National-Oekonomik des Ackerbaues_, pp. 31, 52.
Stuttgart, 1888.

[110] _Ibid._, p. 56, Note 5.

[111] For these and other averages, Sir John Lubbock, Prehistoric Times,
pp. 593-595. New York, 1872.

[112] Roscher, _National-Oekonomik des Ackerbaues_, pp. 79-80, p. 81,
Note 7. Stuttgart, 1888. William I. Thomas, Source Book for Social
Origins, pp. 96-112. Chicago, 1909.

[113] Capt. J. Forsyth, The Highlands of Central India, pp. 101-107,
168. London, 1889.

[114] Tacitus, _Germania_, III.

[115] Roscher, _National-Oekonomik des Ackerbaues_, p. 32, Note 15 on p.
36. Stuttgart, 1888.

[116] E. Huntington, The Pulse of Asia, pp. 202, 203, 212, 213, 236-237.
Boston, 1907.

[117] Sheldon Jackson, Introduction of Domesticated Reindeer into
Alaska, pp. 20, 25-29, 127-129. Washington, 1894.

[118] Quoted in Alexander von Humboldt, Aspects of Nature in Different
Lands, pp. 62, 139. Philadelphia, 1849.

[119] Edward John Payne, History of the New World Called America, Vol.
I, pp. 311-321. 333-354, 364-366. New York, 1892.

[120] Prescott, Conquest of Peru, Vol. I, p. 47. New York, 1848.

[121] McGee and Thomas, Prehistoric North America, Vol. XIX, pp.
151-161, of _The History of North America_, edited by Francis W. Thorpe,
Philadelphia, 1905.

[122] Ratzel, _Anthropo-geographie_, Vol. II, pp. 264-265.

[123] Malthus, Principles of Population, Chapters V and VII. London,
1878.

[124] Nathaniel Shaler, Nature and Man in America, pp. 147-151. W.Z.
Ripley, Races of Europe, Chap. I, New York, 1899.

[125] Justus Perthes, _Taschen-Atlas_, pp. 44, 47. Gotha, 1910.

CHAPTER IV

THE MOVEMENTS OF PEOPLES IN THEIR GEOGRAPHICAL SIGNIFICANCE

[Sidenote: Universality of these movements.]

The ethnic and political boundaries of Europe to-day are the residuum o