152 Cincinnati Society of Natural History. 



being as near a right-angle as that, of Agrippa, or of approaching a 

 match for the ideal "front of Jove." " But the facial angle estab- 

 lished by Camper does not mean as much as its author would have 

 us believe. The skull of the Marmoset monkey presents an 

 approach to a right-angle as near as that of a philosopher. Mental 

 capacity depends not altogether upon a prominent forehead, but 

 largely upon the quantity and quality of the brain, as a whole. 

 Even a big brain is sometimes indicative of a block-head. The 

 absence of jaws in a cranium makes the forehead appear low and 

 sloping. Actual measurements of the Riverside skull do not sus- 

 tain the impression of its being pithecoid. External tests with 

 callipers show its longest diameter - from glabella to inion — to be 7 

 inches, its width between parietal prominences to be 53^ inches 

 and from vertex to basilar process of occiput to be 5^3 inches; 

 These measurements indicate that the cranium is neither dulich. 

 ocephalic (long-headed) nor brachycephalic (short-headed). The- 

 zygomatic processes are only averagely developed, and the tem- 

 poral fossae are not decidedly deep, to represent unusually powerful 

 masticating muscles. The brain-pan is as capacious as that of the 

 average savage — almost as large as that of the medium white man. 

 The Riverside skull holds 90 cubic inches, therefore a brain 

 which would fill the cavity must weigh 57^ ounces. The cranial 

 capacity of a Digger Indian, whose skull was sent from California, 

 is identically the same — 90 cubic inches. In making the measure- 

 ments, avoirdupois weight was employed. Troy ounces are for 

 weighing gold, silver, and medicines. The avoirdupois scheme 

 calls for 457/4 grains to the ounce, and 7,000 grains to the pound. 

 The metrical system is at present in reputable use for scientific 

 measurements, but is not in common employment. A grannne 

 contains 15.5 grains, therefore it is a mere matter of mathematics 

 to ascertain how many grammes there may be in one ounce. I 

 have learned experimentally that there are 278 grains in a cubic 

 inch of human brain, hence it is a sum in arithmetic to determine how 

 many grains or ounces, or gv&x\ grammes, there may be in so many 

 cubic inches. A cup an inch scjuare represents a cubic inch ; and 

 if small seeds be used to pour from the full cup into the^ foramen 

 magnum of a skull, the cubic capacity of the brain-pan may be 

 ascertained. If the number of cubic inches be multiplied by 437^, 

 and the amount be divided by 278, the number of avoirdupois 

 ounces may be learned. 



