CEREBR1C ACID. 69 



these melonets hitherto examined is the melonet of potassium. It 

 may be formed by fusing sulphocyanate of potash in a porcelain 

 crucible at a red heat, adding melon as long as an evolution of 

 bisulphuret of carbon and sulphur is observed. A brown opaque 

 glassy mass is obtained, which, being dissolved in boiling water, 

 and the solution allowed to cool, deposits hydrated crystals of 

 melonet of potassium. It may be formed also by fusing five parts 

 of butter of antimony with eight parts of sulphocyanate of potash, 

 and removing by boiling water the soluble portion of the resi- 

 due, after the sulphur and bisulphuret of carbon have been dri- 

 ven off. 



It crystallizes from its aqueous solution in fine needles, which 

 collect into large flocks. A concentrated solution congeals into 

 a white mass, not easily dissolved in cold water. The crystals 

 contain water of crystallization, which they lose when heated. 

 They then fuse without loss of weight into a transparent yellow 

 glass. The solution of this compound is tasteless, and precipi- 

 tates all earthy and metalline salts. 



SECTION XV. OF CEREBRIC ACID. 



This substance, which constitutes an important constituent of 

 the brain, was first noticed by Vauquelin in his chemical analy- 

 sis of the brain, published in 1812 * He gives it the name of 

 white fatty matter ; but did not obtain it in a state of purity ; 

 Kiihn also noticed it under the name oimyelocone. f Couerbe, in 

 1834, obtained it also, though not in a state of complete purity, 

 and gave it the name of cerebrote. J In 1841 it was again ex- 

 amined by Fremy, who brought it to a state of comparative 

 purity, discovered its acid properties, and gave it the name of 

 cerebric acid. 



Couerbe's method of obtaining it was to digest the matter of 

 brain in ether, till every thing soluble in that liquid was remov- 

 ed, the residue was treated with boiling alcohol, as long as any 

 thing continued to dissolve. The alcohol, on cooling, deposited 

 a white 'matter consisting chiefly of cerebrote and cholesterin. 

 Cold alcohol dissolved the latter of these substances, and left 

 the cerebrote. But Fremy ascertained that cerebrote obtained 

 in this way still contained sensible quantities of cerebrate of lime 



* Ann. de Chim. Ixxxi. 37, or Annals of Philosophy, i. 332. 



f Dissert, de Cholestearine, p. 20. \ Ann, de Chim. et de Phys. Ivi. 171 



Jour, de Pharmacie, xxvii. 439. 



