



378 Dr. W. Hunter. The Influence of [Mar. 



to left and left to right ; the fluid was thus kept in continual 

 agitation, and uniformly distributed over the inner surface of the 

 cylinder. 



(2.) Moderate Supply of Oxygen. The fluid was placed in a wide- 

 mouthed jar, and stirred freely from time to time. 



(3.) Exclusion of Oxygen. The fluid was placed in a narrow-necked 

 bottle which it nearly filled ; excess of oxygen at the outset was 

 driven out by a stream of hydrogen ; the bottle was then tightly 

 closed by an india-rubber stopper through which passed a glass tube 

 suitably bent and opening externally under mercury. 



In (2) and (3), the vessels were maintained at a uniform tempera- 

 ture of 32 by being suspended in a water tank. In most of the ex- 

 periments, a certain quantity of extract of pancreas was added, to 

 hasten putrefaction, with 10 grams of CaC0 3 to prevent the in- 

 jurious action of the acids formed in the early stages of the process. 



The conditions of the experiments varied somewhat in other 

 respects, either as regards the quantities of material used, or its 

 nature, or the manner of dealing with it. The experiments made, 

 eight in number, thus divide themselves into three series, each made 

 up of two or three different observations under the conditions above 

 noted. 



The attempts made in the earlier experiments to isolate the indi- 

 vidual ptomaines in the form of their platinum or gold salts failed, 

 owing to the small quantities present. 



Attention was afterwards confined to the diamines, and accurate 

 quantitative results were obtained by use of benzoyl chloride ft 

 reagent which, as Udranzky and Baumann have shown, forms bulky 

 and stable derivatives with all bodies of this nature. 



Results. 



The results of the observations show : 



(1.) That a free supply of oxygen prevents entirely the formation 

 of ptomaines, the only base found under such circumstances and 

 that too from the very first being ammonia. 



(2.) With one exception, all the experiments agree in showing 

 that, as judged by the relative quantities of diamines formed, the 

 greatest formation of ptomaines takes place when oxygen is entirely 

 excluded. 



The differences between moderate supply of oxygen and entire 

 absence in this respect ranged from 2:1 to as much as 27 : 1 in the 

 observations made, the greatest formation always taking place where 

 oxygen was excluded. 



The one exception to this can be explained by a difference in the 

 procedure, the effect of which was probably to destroy a large number 



