A BASE. 261 



boiling water, but decomposes. In recrystallizing, warm, previously 

 boiled water should be used. 



The aurochlorid, CjqHjjN.HCI.AuCIj, occurs as a light yellow 

 precipitate ; insoluble in cold water, soluble in warm water. It is 

 decomposed by boiling water ; is stable when kept in a moist atmos- 

 phere. 



The iodomethylate, CjjHjjN.CHjI, in warm alcoholic solution 

 yields, on the addition of strong potash, a bright red color, which 

 soon becomes brown, and in about an hour the solution shows a 

 greenish-blue fluorescence. This rapidity of change is due to the 

 extreme oxidizability of the ptomaiin. 



On careful oxidation with potassium permanganate at ordinary 

 temperature it yields a solid acid, having a melting-point of 228°— 

 229°, the same as that of the pyridin carbonic acid of Huber and 

 Laidlin, obtained by the oxidation of nicotin. The solubility in 

 cold and in warm water and in absolute alcohol is the same as that 

 of nicotinic acid. It begins to sublime at 150° as pearly spangles. 

 The formula is CgH^NOj. On distillation with lime pyridin forms. 

 It is, therefore, identical with nicotinic acid, an oxidation product 

 of nicotin and other volatile alkaloids. 



O. de Coninck considers this base, as well as CgHjjN, as belong- 

 ing to the pyridin, and not to the hydropyridin series. 



A Base, Ci^Hj^N, was described by Griffiths (1890) as derived 

 from cultures on pepton-agar of the bacterium allii, a germ obtained 

 from putrid onions. The base (hydrochlorid ?) forms colorless, pris- 

 matic, microscopic, very deliquescent needles, which are soluble in 

 warm water, alcohol, ether and chloroform. It gives a hawthorn- 

 like odor, especially when warmed. With phosphomolybdic acid it 

 yields a white ; with iodin in potassium iodid and with tannic acid a 

 chestnut-colored precipitate. Nessler's solution produces a yellow 

 chestnut-colored precipitate. Picric acid throws down a yellow 

 slightly soluble deposit. The platinochlorid, (Ci„HjjN.HCl)2PtCl^, 

 is yellow, crystalline, and difficultly soluble in cold water and in 

 alcohol ; soluble in warm water. Gold chlorid produces a thick yel- 

 low precipitate soluble in water. Dilute sulphuric acid produces a 

 violet-red color. The base is apparently a hydrocoridin. 



Griffiths has also described, together with a variety of other prod- 

 ucts in physiological chemistry, the basic compounds which are given 

 in the subjoined table. The method employed in the isolation of all 

 but few of these compounds is that of Luff (see next chapter under 

 urine). 



