LECTURE II. 35 



contrary, the face projects in a muzzle, whilst the forehead and 

 the cranium recede. Camper endeavoured to express this 

 relation by his facial angle. The more the muzzle projects and 

 the forehead recedes, the more acute must be the angle formed 

 by two lines, one of which is drawn from the aural aperture to 

 the margin of the upper jaw, and the other from the jaw to the 

 most prominent point of the forehead. It is true. Gentlemen, 

 that the facial angle does not altogether answer its purpose ; it 

 is true that Camper did not definitely determine it, so that 

 some take the angle at the nasal spine, others at the alveolar 

 margin. It is also true that there are skulls in which the pro- 

 jecting snouts depend almost entirely upon the formation of 

 the jaws. In many cases, too, the eyebrows are very promi- 

 nent, such prominence depending not upon the development 

 of the brain, but upon that of the frontal sinuses, which are 

 connected with the nose. But, granting all these objections, 

 it must be admitted that similar ones may be made to most 

 other measurements, and that conclusions as to the general 

 proportions of a skull cannot be deduced from a single measure- 

 ment. Camper's angle alone cannot affbrd a valid standard of 

 the relative proportions of skull and face, still it fairly repre- 

 sents these proportions, and should in no case be neglected. 



It must not be forgotten that all these observations, which 

 have for their object the determination, not merely of the 

 external form of the head, but of the proportions of its parts, 

 have to be made chiefly on the dead skull, and not on the 

 Hving head. The real proportions can only be ascertained 

 when the skull is bisected, so that both the right and left 

 halves may be inspected and measured internally and ex- 

 ternally. As I cannot expect you to be acquainted with 

 anatomical details, I venture to offer a few explanations, which 

 I shall endeavour to make as short as possible. 



The basis of the cranium, upon which the brain rests, 

 consists essentially of four bones : the occipital, the sphe- 

 noid, the ethmoid, and the frontal. By the aperture in the 

 occipital the spinal cord reaches the brain; the optic nerve 

 passes through the sphenoid to the eye, and the olfactory 

 through the ethmoid bone. We need not notice the frontal 



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