Of the blackness of the skin, the principal cause is the heat of the climate. When this heat is excessive, as at Senegal, and in Guinea, the inhabitants are entirely black; when it is rather less violent, as on the eastern coasts of Africa, they are of a shade more light; when it becomes somewhat temperate, as in Barbary, Mogul, Arabia, &c. they are only brown; and in fine, when it is altogether temperate, as in Europe and in Asia, they are white; and the varieties there remarked proceed solely from the mode of living. All the Tartars, for example, are tawny, while the Europeans, who live in the same latitude, are white. This difference clearly arises from the former being always exposed to the air; having no towns nor fixed habitations; sleeping upon the earth, and living coarsely and savagely. These circumstances are sufficient to render them less white than the Europeans, who want nothing to render life comfortable and agreeable. Why are the Chinese whiter than the Tartars, whom they resemble in all their features? Certainly from the above reasons. When cold becomes extreme, it produces effects similar to those of excessive heat. The Samoiedes, Laplanders, and Greenlanders, are very tawny; and it is even asserted, that some Greenlanders are as black as those of Africa. Here the two extremes meet. Violent cold and violent heat produce the same effect upon the skin, because these two causes act by a quality which they possess in common. Dryness of the air is this quality; and which cold is as equally productive as intense heat; by either the skin may be dried, and rendered as tawny as what we find it among the Laplanders. Cold compresses all the productions of nature; and thus it is that the Laplanders, who are perpetually exposed to the rigours of frost, are the smallest of the human species. The most temperate climate is between the degrees of 40 and 50; where the human form is in its greatest perfection; and where we ought to form our ideas of the real and natural colour of man. Situated under this Zone the civilized countries are, Georgia, Circassia, the Ukraine, Turkey in Europe, Hungary, South Germany, Italy, Switzerland, France, and the North of Spain; of all which the inhabitants are the most beautiful people in the world.