234- Intelligence and Miscellaneous Articles, 



the powder, which has become of a deep brown colour, is to be 

 washed and dried and treated with boiling aether, which dissolves 

 the curcumine and leaves the sulphuret of lead. 



By evaporating the aether slowly, the curcumine is deposited in thin 

 laminae, which are transparent and inodorous ; when reduced to a 

 fine powder, curcumine is of a beautiful yellow colour, which is more 

 intense as the powder is finer ; in small laminae it is of cinnamon 

 colour, but when held up to the light it is of a deep red colour. 



By the process above described, about half an ounce of curcumine 

 was obtained from a pound of the root ; attempts were made, but in 

 vain, to sublime and crystallize it. At 104° Fahr. it fuses, and even 

 at common temperatures the fine powder agglutinates; it burns 

 with a bright flame accompanied with much soot ; by exposure to 

 the sun's rays it soon loses its intense colour, and becomes gradually 

 of a yellowish- white ; as curcumine is insoluble in water, but very 

 soluble in alcohol and in aether, it appears to resemble the resins. 



M. Chevreul had already stated that curcumine is composed of oxy- 

 gen, carbon and hydrogen, and M. Vogel proved that it contained 

 no azote, by fusing it in a tube with six times its weight of hydrate 

 of potash, no trace of ammonia being obtained. 



The mean of four combustions of curcumine, prepared as above 

 described, yielded 



Carbon .... 69'501 

 Hydrogen . . 7*460 



Oxygen 23039— 100' 



Journal de Pharm. et de Chim., Juillet 1842. 



ON THE ACTION OF ACIDS ON CURCUMINE. BY M. VOGEL, JUN. 



Dilute acids do not dissolve curcumine, but the concentrated do. 

 When concentrated sulphuric acid is poured upon powdered curcu- 

 mine it is dissolved, and a crimson solution is obtained ; the red 

 colour immediately disappears on the addition of water, and green- 

 ish-yellow fiocculi are deposited, which appear to be pure curcumine ; 

 and hydrochloric and phosphoric acids act in a similar manner, but 

 concentrated acetic acid dissolves it without effecting any change in 

 its colour. 



The action of nitric acid differs from the above. One part of 

 curcumine was mixed, in a porcelain capsule, with two parts of 

 concentrated nitric acid, previously diluted with an equal volume 

 of water ; at common temperatures no change appeared to take 

 place, but when heated in a sand-bath rapid action occurred, the 

 liquid rose in bubbles, so that it was requisite to remove the vessel 

 from the fire till the violence of the action ceased ; after this the 

 mixture was gently heated till it ceased to evolve any gas ; by this 

 action the curcumine is separated into a resinous mass, which is de- 

 posited in yellow fragments, and a yellow substance, soluble in wa- 

 ter. The resinous substance, when repeatedly washed with hot 

 water, and afterwards dried, may be easily reduced to a fine powder, 

 which is yellow, and differs much from curcumine on account of its 



