702 



NERVOUS SYSTEM. 



In concluding this portion of our argument, we present a table of an exceedingly inter- 

 esting series of observations upon the comparative weights of the encephalon in the Cauca- 

 sian, the negro, and the intermediate grades produced by the union of the two races. The 

 observations in this table are hardly sufficient in number to establish the exact relations 

 between the brains in the different grades of color, but they illustrate points of peculiar 

 interest in this country, where the blacks are so numerous and where the union of the 

 two races, white and black, is so common. We also give a list of some of the well- 

 authenticated weights of the encephalon in men whose intellectual faculties had been 

 observed during life. This latter list we have prepared with great care and have intro- 

 duced some observations not found in most works upon physiology. In estimating the 

 intellectual power of individuals, it is difficult to arrive at exact conclusions, except with 

 regard to men of acknowledged eminence. Still, the statements are as accurate as pos- 

 sible and must be taken for what they are worth. Several of the examples given in this 

 list are marked exceptions to the general rule, that the mental vigor is in proportion to 

 the amount of brain-substance. 



We have not considered it necessary to enter into a discussion of the relations of the 

 facial angle to intelligence in the lower animals and in different races of men. It was 

 proposed by Camper to take the angle made at the junction of two lines, one drawn from 

 the most projecting part of the forehead to the alveolae of the teeth of the upper jaw, 

 and another passing horizontally backward from the lower extremity of the first line, as 

 the facial angle. This angle is, to a certain extent, a measure of the projection of the 

 anterior lobes of the brain. Numerous observations upon the facial angle in different 

 races were made by Camper and by other physiologists and ethnologists. They show, in 

 general terms, that the angle is larger in man than in any of the inferior animals and is 

 largest in those races that possess the greatest development of intellectual power. 



Ethnological Table, derived from 405 Autopsies of White and Negro Brains. Made 

 under the Direction of Surgeon Ira Russell, 11th Massachusetts Volunteers. 



Table of Weights of the Encephalon, in ounces, av., in Individuals, in some of whom the 

 Degree of Intelligence is more or less accurately known. 



Congenital imbecile, aged 30; height 5 feet 8 inches ; died of phthisis (West Riding Lu- 

 natic Asylum Reports, London, 1876, p. 19) 70'50 oz. 



Bricklayer, aged 38 ; fair intelligence, but could neither read nor write (reported by Dr. 



James Morris) 67*00 " 



Cuvier, aged 63 (Archives gentralcs de medecine, 1832) 64*33 " 



