280 Notices of the Labours of Continental Chemists. 



tein compounds with nitric acid; the dried product must be 

 often treated with water and boiling alcohol. It was dis- 

 solved in ammonia, evaporated, dissolved again in water, and 

 the solution treated with chlorine : the red colour gradually 

 disappeared, and a whitish or yellowish flocculent precipi- 

 tate was produced, which when washed and dried at 100° is 



lemon-yellow coloured. Formula C^* H'°° N'« O's CI, or 



2 {O* H« N^ O'- + H- O) + CI- Ok Heated above 100° it 

 loses water and some chlorous acid. With ammonia it 

 evolves nitrogen ; if the fluid be evaporated and the sal-am- 

 moniac extracted with alcohol, the yellow acid remains. 



When xanthoproteinate of ammonia is heated to 140° the 

 ammonia is driven off, and the hydrated acid remains. For- 

 mula C" H" N^ 0'3 =C H^' N« O'^ + H^ O. 



Actio?i (f Potash and Soda on Indigo — Anilin. 



M. Fritzsche has found, that when finely-powdered in- 

 digo is thrown into a hot and very concentrated solution of 

 caustic potassa or soda contained in a retort, the blue colour 

 is destroyed and a reddish-brown mass produced, containing 

 a peculiar acid ; when this is still further heated, a vola- 

 tile body is given off^ which condenses in the neck of the 

 retort into oily drops, and ammoniacal water distills over. 

 By re-distillation this oil may be obtained colourless; its 

 quantity is about 18 or 20 per cent, of the employed indigo; 

 hQ cs\h \\. anilin. Specific gravity 1"028; refracts light pow- 

 erfully, and has a strong aromatic but at the same time dis- 

 agreeable smell ; is but little soluble in water ; mixes in all pro- 

 portions with alcohol and aether. Exposed to air anilin be- 

 comes yellow, and at length is metamorphosed into a resin. 

 Boils at 228° C. It dissolves sulphur. Anilin contains no 

 oxygen; its formula isC'"H'*N-. Atomic weight 1181-6. 

 It forms salts with acids ; with the oxyacids it combines and 

 takes up one atom of water; with the hydracids it unites di- 

 rectly ; in this respect it is similar to ammonia. Oxalate of 

 anilin is formed when alcoholic solutions of anilin and of ox- 

 alic acid are mixed together; it is a white powder, which is to 

 be washed with alcohol, and then dissolved in hot water, from 

 which it separates on cooling in long crystals. Formula C'- 

 Hi4 N- + C^ 03 + H'^ O. {Annalen der Chemie und Phar- 

 viacie, xxxvi. p. 84.) 



Hydrochlorate of anilin is obtained by mixing anilin with 

 hydrochloric acid and re-crystallization of the salt, which is 

 easily soluble in water, C'- H'^ N- + CI- H'-. 



Other salts have been formed but not examined; the ac- 



