COLOUR, (dOrerence of in the human species.) Of all the external varieties in the human species, none arc so remarkable as that diversity of colour which distinguish es the inhabitants of different regions of the globe. \\ c see it in all its gradations, from the purest white, to the deepest ebony; and the question is, to ascertain the cause these variations. Two hypotheses have been main tamed on this subject ; the one is, that all the varieties of colour may be accounted for from the effects of cli mate ; the other is, that there have been, from the begin ning, different species of the human race, possessing dif ferent colours, as their peculiar characteristics.
The first opinion is the most ancient, and we think i' has been demonstrated to be the most philosophical. The ancients, who were scarcely acquainted with any black nation, except the Nubians, regarded them as the terminating shade of the tawny colour, heightened into blackness by perpetual exposure to the rays of the sun. As far as their knowledge then went, every thing tended to confirm this opinion. They observed the shade of co lour gradually to deepen as they approached the equa tor; whilst those nations which were farthest removed from the torrid zone, were uniformly found to hat e the fairest complexions: they could not therefore desire a more complete induction of facts to authorise their con clusion, that the different shades of colour were to be as cribed to the effects of climate.
Modern discoveries have greatly enlarged our know ledge, and furnished us with many facts totally unknown to the ancients. There are now found many exceptions to the rule which they adopted, and nations of very dif ferent complexions are found under the same parallel of latitude. This discovery first gave rise to the hypothe sis, that different regions of the globe ha. e been peopled with different races of men. But if we take the thermo meter for our guide, and estimate by the degree of heat, rather than the degiec of latitude, we shall has e a rule which approaches nearer to the truth, though subject to modifications which we shall afterwards specify.
It is impossible to estimate the degree of heat in any country, merely by measuring its distance from the equa tor : its climate is affected by its elevation abol c the sea, by the height of its mountains, by the extent of conti nent, or by the nature of its surface. All these circum stances operate with peculiar force on the continent of America, which is found to differ as much from the old world in its surface, and in the temperature of its climate, as its natives differ in appearance from other inhabitants of the globe. There arc no blacks found in Aincrica, through stretches ough the torrid zone setches across its continent But this is exactly what we might expect. on the suppo' sition that the colour is affected principally by heat. The immense extent of ocean by which its shores are bounded, its lofty mountains, running almost continuously from one extremity of the continent to the other, with their tops covered with perpetual snow, cool the scorching breezes of the torrid zone, and convert it into a temperate clime. Were we then to find negroes in the torrid zone in Ame rica, as we find them in Africa, it would be the surest proof that they were a different race tram the rest of mankind, as it would be evident that their colour could not be ascribed to the effects of heat. The plain of
Mexico, according to Humboldt, is about eight thousand feet above the level of the sea, and this circumstance, though it lies within the torrid zone, must necessarily en sure a temperate climate ; the inhabitants, of course, are found to be only of a tawny complexion. Similar causes operate throughout the whole extent of America, pro ducing an uniformity of climate unknown in the ancient world, and consequently a much greater uniformity in the appearance of its inhabitants.
To this reasoning, however, it has been objected, that the difference of colour cannot be ascribed to heat, since tribes have been found within the torrid zone, in Africa, separated from each other only by a river, yet differing widely in appearance and complexion. Thus it is said, that on one side of the river Senegal, the inhabitants are perfectly black, on the other only tawny. If this be the fact, and we are not concerned to dispute it, we must seek for some modification of the principle which we have laid down, viz that the difference of colour is to be ascribed to the different degrees of heat ; and it is easy to account for this apparent anomaly without relinquish ing the principle which we have assumed. It is evident, that the form and colour of the human body are much affected by the degree of refinement to which a nation has attained, by the food on which it subsists, or by the occupations in which it is most usually engaged. We observe a wide difference of appearance in the different ranks of European society, varying, in general, accord ing to the station or employment of different individuals. May we not expect to see the same difference among rude tribes, placed in the same circumstances as to tem perature, but differing widely in their general habits and employments ? If cleanliness should ever become an object with any tribe in the torrid zone, or if they should ever alter their ideas so completely, as to esteem blanch ing of the skin a beauty, in that case there can be little doubt that even the Ethiopian might in some degree change the ebon gloss of his complexion. But though we cannot expect this change of complexion to be effect ed by any voluntary effort on the part of people, who esteem blackness beautiful, and who unquestionably find it convenient ; ) et it may be produced by circumstances over which they have no cotttroul, or by habits which they may be unwilling to relinquish. There can be no doubt that their colour must be considerably affected by the nature and quality of the food on which they subsist. We see a visible difference in the flesh of the same ani mals, according to the nature of their food, and we must naturally suppose the sante effects to be produced on the human body, by the same circumstances. A tribe which lives chiefly on fruit, or vegetable productions, may be expected, cxicrie naribus, to differ in complexion from those who live on fish, or animal food ; and they who live on clean and wholesome nourishment, from those who feed on coarse and filthy fare.