Though these Arctic folk are sprung from diverse race stocks, close vicinal location around an enclosed sea has produced some degree of blood relationship. But whatever their origins, the harsh conditions of their life have imposed upon them all a similar civilization. All population is sparse and more or less nomadic, since agriculture alone roots settlement. They have the same food, the same clothing, the same types of summer and winter dwellings, whether it is the earth hut of the Eskimo or of the coast Lapp, the Siberian Yukagirs of the Kolima River, or the Samoyedes of northeastern Russia.[1433] The spur of necessity has aroused their ingenuity to a degree found nowhere in the drowsy Tropics of Africa. Dread of cold led the Yakuts of the Lena Valley to glaze the windows of their huts with slabs of ice, which are better nonconductors of heat and cold, and can be made more perfectly air-tight than glass. Hence these windows have been adopted by Russian colonists. The Eskimo devised the oil lamp, an invention found nowhere else in primitive America, and fishing tackle so perfect that white men coming to fish in Arctic waters found it superior to their own.
Owing to the inexorable restriction of their natural resources, contact with European commerce has impoverished the Hyperborean natives. It has caused the rapid and ruthless exploitation of their meager resources, which means eventual starvation. So long as the Ostyaks, before the coming of the Russians, were sole masters of the vast forests of the Obi Valley, they commanded a supply of fish and fur animals which sufficed for their sparse population. But the greed of the Russian fish dealers and fur traders, and the devastating work of the lumbermen have made double war upon Ostyak sources of subsistence.[1434] The appearance of the white man in Alaskan waters was the signal for the indiscriminate killing of seal and other marine animals, till the Eskimo's supply of food and furs has been seriously invaded, from Greenland to the outermost Aleutian Islands. In all this wide territory, climatic conditions forbid any substitute for the original products, except the domesticated reindeer on the tundra of the mainland; but this would necessitate the transformation of the Eskimo from a hunting to a pastoral people. This task the government at Washington has undertaken, but with scant success.
Cold and health
In contrast to the numerous indirect effects of a frigid climate, no direct physiological effect can be positively ascribed to intense cold. It lays no bodily handicap on health and energy, as does the excessive heat of the Tropics. The coldest regions where tillage is possible are tolerable places of residence, because their winters are intensely dry. That of central Siberia, which is drier than the driest desert, makes tent life comfortable in the coldest season, provided the tenter be clad in furs. The low temperatures of the Canadian Northwest for the same reason have not repelled settlers even from the Southern States. Negroes, however, meet a climatic barrier in America at the isotherm of 5° Centigrade (41° F.). They are found in New England and Nova Scotia, generally with a large admixture of white blood; but there and farther north where the climate is moist as well as cold, they show a fatal tendency to pulmonary diseases.
The small amount of tropical emigration
The acclimatization of tropical people in temperate regions will never be a question of widespread importance. The negroes were involuntary immigrants to America, under conditions that can never recur. Their concentration in the "black belt," where they find the heat and moisture in which they thrive, and their climatically conditioned exclusion from the more northern states are matters of local significance. Economic and social retardation have kept the hot belt relatively underpopulated. The density map shows much the largest part of it with a population less than 25 to the square mile. Only the small portion contained in India, southernmost China, and Java shows a density over 125 to the square mile (or 50 to the square kilometer). This density has to rise to 500 or more to the square mile before emigration begins. The would-be exiles then have a wide choice of new homes in other tropical lands, where they find congenial climate and phases of economic development into which they will fit. East Indian coolies are found in Cape Colony, Natal, Zanzibar, Trinidad, and British Guiana, where they constitute 38 per cent. of the population.
Effects of tropical climate.