_Camper_ took the lead. He was not content with deciding upon merely superficial appearances, but wished to rest his demonstrations upon a mathematical basis, by defining, anatomically, the distinguishing characteristics of different types. If he succeeded in this, he would thereby establish a strict and logical method of treating the subject, preclude all doubt, and give to his opinions that rigorous precision without which there is no true science. I borrow from Mr. Prichard,[122] Camper's own account of his method. "The basis on which the distinction of nations[123] is founded, says he, may be displayed by two straight lines; one of which is to be drawn through the _meatus auditorius_ (the external entrance of the ear) to the base of the nose; and the other touching the prominent centre of the forehead, and falling thence on the most prominent part of the upper jaw-bone, the head being viewed in profile. In the angle produced by these two lines, may be said to consist, not only the distinctions between the skulls of the several species of animals, but also those which are found to exist between different nations; and it might be concluded that nature has availed herself of this angle to mark out the diversities of the animal kingdom, and at the same time to establish a scale from the inferior tribes up to the most beautiful forms which are found in the human species. Thus it will be found that the heads of birds display the smallest angle, and that it always becomes of greater extent as the animal approaches more nearly to the human figure. Thus, there is one species of the ape tribe, in which the head has a facial angle of forty-two degrees; in another animal of the same family, which is one of those simiæ most approximating in figure to mankind, the facial angle contains exactly fifty degrees. Next to this is the head of an African negro, which, as well as that of the Kalmuc, forms an angle of seventy degrees; while the angle discovered in the heads of Europeans contains eighty degrees. On this difference of ten degrees in the facial angle, the superior beauty of the European depends; while that high character of sublime beauty, which is so striking in some works of ancient statuary, as in the head of Apollo, and in the Medusa of Sisocles, is given by an angle which amounts to one hundred degrees."