Beside these two great defects, the method is very open to attack in that it does not apply to all the varieties of the human race. It leaves out of account the tribes with pyramidally shaped heads, who form, however, a striking division by themselves. Blumenbach, who held the field against his predecessor, elaborated a system in his turn; this was to study a man’s head from the top. He called his discovery _norma verticalis_, the “vertical method.” He was confident that the comparison of heads according to their width brought out the chief differences in the general configuration of the skull. According to him, the study of this part of the body is so pregnant with results, especially in its bearing on national character, that it is impossible to measure all the differences merely by lines and angles; to reach a satisfying basis of classification, we must consider the heads from the point of view in which we can take in at one glance the greatest number of varieties. His idea was, in outline, as follows: “Arrange the skulls that you wish to compare in such a way that the jaw-bones are on the same horizontal line; in other words, let each rest on its lower jaw. Then stand behind the skulls and fix the eye on the vertex of each. In this way you will best see the varieties of shape that have most to do with national character; these consist either (1) in the direction of the jaw-bone and maxillary, or (2) in the breadth or narrowness of the oval outline presented by the top half of the skull, or (3) in the flattened or vaulted form of the frontal bone.”[52] Blumenbach’s system resulted in the division of mankind into five main categories, which were in their turn subdivided into a certain number of types and classes. This classification was of very doubtful value. Like that of Camper, it overlooked many important characteristics. It was partly to escape such objections that Owen proposed to examine skulls, not from the top, but from the bottom. One of the chief results of this new method was to show such a strong and definite line of difference between a man and an orang-outang that it became for ever impossible to find the link that Camper imagined to exist between the two species. In fact, one glance at the two skulls, from Owen’s point of view, is enough to bring out their radical difference. The diameter from front to back is longer in the orang-outang than in man; the zygomatic arch, instead of being wholly in the front part of the base, is in the middle, and occupies just a third of its diameter. Finally the position of the occipital orifice, which has such a marked influence on general structure and habits, is quite different. In the skull of a man, it is almost at the centre of the base; in that of an orang-outang, it is a sixth of the way from the hinder end.[53]