BRAIN AND NERVES. 1059 



Brain and nerves. The substance of the brain has been ex- 

 amined by more than one chemist, but most recently by M. 

 Fremy. The brain of man contains 7 parts of albumen, 5 parts 

 of a fatty matter, and 80 parts of water. The albuminous por- 

 tion, after being coagulated by heat, is insoluble in water, alco- 

 hol and ether. The fatty matter is what has principally occu- 

 pied attention ; besides portions of the ordinary fatty substances, 

 it contains two peculiar acids and cholesterin : 



1. Cerebric acid which when purified is white, and presents it- 

 self in crystalline grains. It dissolves without residue in boiling 

 alcohol, is almost insoluble in cold ether, more soluble in boiling 

 ether. It has the remarkable property of swelling up like starch 

 in boiling water, but appears to be insoluble in that liquid. It 

 enters into fusion at a high temperature, approaching closely that 

 at which it is decomposed, and is combustible. It contains no 

 sulphur, but some phosphorus. The result of its analysis by 

 Fremy, is 66.7 per cent of carbon, 10.6 of hydrogen, 2. 3 of nitro- 

 gen, 0.9 of phosphorus, 19.5 of oxygen. 



2. Oleophosphoric acid, which is separated from the former 

 acid, by its solubility in ether. It is still accompanied by 

 oleine and cholesterin, which are withdrawn from it by 

 alcohol and ether. This acid is of a viscid consistence, 

 insoluble in cold alcohol, but dissolving easily in boiling 

 alcohol ; it is insoluble in ether. Placed in contact with 

 potash, soda and ammonia, it immediately gives soapy com- 

 pounds. It forms compounds insoluble in water with other 

 bases. M. Fremy has observed a remarkable transformation of 

 oleophosphoric acid. When boiled for a long time in water or 

 alcohol, it gradually loses its viscidity and becomes a fluid oil, 

 which is pure oleine ; while the liquor contains phosphoric acid. 

 This decomposition becomes very rapid, when the liquor is 

 rendered slightly acid. Although M. Fremy's attempts to form 

 this acid directly, by uniting oleine and phosphoric acid, were 

 unsuccessful, he still deems it probable that this acid may 

 consist of the elements in question, and be analogous to the 

 compound of sulphuric acid and oleine or sulpholeic acid (page 

 968). It contains from 1.9 to 2 per cent of phosphorus, in the 

 condition, it is thus represented, of phosphoric acid. 



M. Fremy has given a process for extracting cholesterin (page 

 1048) from the brain, in considerable quantity. 



2 z z 2 



