Destructive Distillation of Animal Substances, 459 



half-full, and after two or three days, during which the agitation 

 was frequently repeated, more water was added, and the solution 

 of the bases separated from the oil. To this fluid acid was 

 added, so as to have a distinct excess ; and it was then boiled for 

 the separation of Runge^s pyrrol, to which reference has been 

 made in the first part of this paper. As, however, I observed 

 that a very powerful and pungent odour was evolved when the 

 fluid began to boil, and tho vapours presented the characteristic 

 reaction of pyrrol in a very high degree, the head of the boiler 

 was luted on, and the condenser attached, for the purpose of 

 endeavouring to obtain that substance, which in my previous 

 experiments I had not done. The fluid which distilled over 

 carried with it a small quantity of oil, which, at the moment of 

 distillation, was perfectly colourless, but soon acquired a reddish 

 shade, and in the course of a few days became almost black. 

 The greater part of this oil passed over with the first portion of 

 water ; but the last traces adhered with great obstinacy to the 

 acid fluid, and could only be separated by very protracted di- 

 stillation. The substance thus obtained proved to be a mixture 

 of an oil insoluble in acids, and which appeared to be merely a 

 small quantity of the crude oil, mechanically mixed with the 

 fluid, and of a series of bases of very remarkable properties, and 

 obviously related to one another, to which I shall afterwards 

 refer under the provisional name oipyirol bases. 



When these substances had entirely distilled, the fluid was 

 allowed to cool, excess of slaked lime added, and the distillation 

 again commenced, in order to obtain the bases which had been 

 retained by the sulphuric acid. The separation of these was 

 conducted in a manner in all respects similar to that employed 

 in the former preparations, solid caustic potash being added in 

 sufficient quantity to cause the separation of the bases held in 

 solution in the water. The potash fluid, however, retained a 

 certain proportion of ammonia, another gaseous base, and of the 

 most volatile bases, which could be separated only by a very 

 large excess of potash. The fluid was therefore distilled in glass 

 vessels, and the product collected in a succession of three re- 

 ceivers, the first of which was kept cold by water, the second by 

 a freezing mixture, and the third contained hydrochloric acid, 

 for the purpose of condensing the gaseous products. The first 

 receiver now contained the bases dissolved in a small quantity of 

 water, from which they were readily separated by potash ; the 

 second receiver contained only a drop or two of liquid ; but in 

 the third the hydrochloric acid was rapidly saturated, and re- 

 quired repeated renewal during the progress of the distillation. 



The hydrochloric solution thus obtained contained a very large 

 quantity of chloride of ammonium, along with a small proportion 



