All over the world physical circumstances control the human race. They make the Australian a savage; incapacitate the negro, who can never invent an alphabet or an arithmetic, and whose theology never passes beyond the stage of sorcery. They cause the Tartars to delight in a diet of milk, and the American Indian to abominate it. They make the dwarfish races of Europe instinctive miners and metallurgists. An artificial control over temperature by dwellings, warm for the winter and cool for the summer; variations of clothing to suit the season of the year, and especially the management of fire, have enabled man to maintain himself in all climates. The invention of artificial light has extended the available term of his life; by giving the night to his use, it has, by the social intercourse it encourages, polished his manners and refined his tastes, perhaps as much as any thing else has aided in his intellectual progress. Indeed, these are among the primary conditions that have occasioned his civilization. Variety of natural conditions gives rise to different national types, artificial inventions occasion renewed modifications. Where there are many climates there will be many forms of men. Herein, as we shall in due season discover, lies the explanation of the energy of European life, and the development of its civilization. Would any one deny the influence of rainy days on our industrial habits and on our mental condition even in a civilized state? With how much more force, then, must such meteorological incidents have acted on the ill-protected, ill-clad, and ill-housed barbarian! Would any one deny the increasing difficulty with which life is maintained as we pass from the southern peninsulas to the more rigorous climates of the north? There is a relationship between the mean annual heat of a locality and the instincts of its inhabitants for food. The Sicilian is satisfied with a light farinaceous repast and a few fruits; the Norwegian requires a strong diet of flesh; to the Laplander it is none the less acceptable if grease of the bear, or train oil, or the blubber of whales be added. Meteorology to no little extent influences the morals; the instinctive propensity to drunkenness is a function of the latitude. Food, houses, clothing, bear a certain relation to the isothermal lines. [Sidenote: But, through artificial inventions, it tends to homogeneousness in modern times.]