BRAIN AND NERVES. 



that of an insane person, the cerebrote was combined with some 

 other substances. To separate them digest the fatty residue in 

 a little ether. Sometimes the cerebrote remains undissolved, 

 and may be obtained by passing the etherial solution through a 

 filter. When the ether dissolves the whole, as sometimes hap- 

 pens, we must evaporate to drive off the ether, and then subject 

 the white fatty matter to the action of boiling alcohol. The al- 

 cohol dissolves three different fatty bodies, one of which is cere- 

 brote, and leaves undissolved a sold brown substance resembling 

 wax. 



When this brown substance is digested in ether, the greater 

 part of it is dissolved, but a brown powder remains, which Cou- 

 erbe has distinguished by the name of stearoconote. 



The ether being evaporated, leaves a faun-coloured substance, 

 which cannot be sufficiently dried to assume the form of a pow- 

 der. To this brown matter Couerbe has given the name of ce- 

 phalote. It was first noticed by Kuhn ; but it is to Couerbe we 

 are indebted for the knowledge of its properties. 



The alcoholic solution is filtered through animal charcoal, 

 and then left to itself. White fatty crystals are deposited, and 

 an additional quantity of them is obtained by concentrating the 

 liquid. These crystals being treated with ether, cerebrote is left 

 in a state of purity, while the ether dissolves a quantity of cho- 

 lesterin, which may be obtained in crystals by evaporating the 

 etherial liquid. 



When the alcoholic liquid from which the crystals had been 

 deposited has been weakened by repeated concentrations, a red 

 oily matter begins to appear. To obtain this oil in a separate 

 state the liquid must be put into a linen cloth and squeezed. The 

 alcohol with the oil passes through the cloth, while the crystals, 

 consisting of cholesterin and cerebrote, remain. Add to the 

 muddy alcoholic liquid a little ether, which will dissolve the oil, 

 and render the liquid transparent. Set the solution aside. The 

 oil gradually subsides while the crystalline matter remains dis- 

 solved in the ether. When enough has subsided it may be puri- 

 fied by filtration. To this oil Couerbe has given the name of elean- 

 cephalote. * 



* I think it right to state that I attempted to extract these various bodies, 

 described by Couerbe from the human brain ; but, with the exception of cere- 

 biote and cholesterin, I was unsuccessful. 



