A manual of practical chemistry; the analysis of foods and the detection of poisons

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1879 Excerpt: ...case, but more feebly, and leaves behind, on evaporation, the yellow chloroform solution. Senegin. y. Sulphuric acid dissolves brown, and the solution becomes red by the addit ion of a little water. The action is very weak. SmUacin. cc. Sulphuric acid dissolves it with the production of a dirty red, hydrochloric acid, in the cold, with that of a reddish-brown colour, and the last solution becomes brown on boiling. Constituents of the hellebore, particularly Jervin. b. Is inactive, and becomes blue by sulphuric acid; hy Frohde's reagent dark cherryred. Hydrochloric acid dissolves it red. The solution becomes by boiling colourless colour; mixed with nitre, then moistened with sulphuric acid, and lastly treated with concentrated soda-lye, it is coloured a brick-red. Picrotoxin. 8. Sulphuric acid dissolves it with the production of a splendid red colour. The substance renders the heart-action of a frog slower. Hdleborine. VI. THE WATERY FLUID IS NOW AGAIN SHAKEN UP WITH PETROLEUM ETHER, In order to take up the rest of the chloroform, and the watery fluid is saturated with ammonia. The watery solution of aconite and emetin is liable to undergo, through free ammonia, a partial decomposition; but on the other hand, it is quite possible to obtain, with very small mixtures of these substances, satisfactory reactions, even out of ammoniacal solutions. VII. THE AMMONIACAL WATERY FLUID WITH PETROLEUM ETHER. In the earlier stages Dragendorff advises the shaking up with petroleum ether at about 40, and the removal of the ether as quickly as possible whilst warm. This is with the intention of separating by this fluid strychnine, brucin, emetin, quinine, veratrine, &c. Finding, however, that a full extraction by petroleum ether is either difficult or not practicable, h...