CoRiAT, CJicniistry of the iXeJi'ous System. 155 



Koch's figures were obtained from the brain of an epileptic. The 

 analysis was conducted with great care and with the aid of more re- 

 cent and accurate methods. 



The wide differences in the figures of these two investigators 

 show how far we are from establishing a comple quantitative composi- 

 tion for the normal human brain. Such figures can only be obtained 

 as the average of a large number of analyses, and they must be firmly 

 established and fully available before we can hope to make any com- 

 parison with pathological brain material. 



The recent studies that have been made on pathological brains 

 and cords, have relate! mainly to diseases where there is extensive 

 general or focal destruction of nerve tissue, as in general paralysis 

 and hemiplegia, comparisons with microscopical findings being made 

 at the same time. W. Barrett, as the result of the analyses of the 

 brains and cords in general paralysis, found an invariable increase in 



