CONDITIONS FAVOUEING FEEMENTATION. 



11 



shoulder of which two platinum electrodes have been inserted. 

 Such a retort may be charged with acid urine ; the urine may be 

 boiled for the requisite time ; and its drawn-out neck may be her- 

 metically sealed whilst the fluid is still boiling. After the fluid 

 has cooled, or after an interval of some days, we can easily liberate 

 a quantity of oxygen and hydrogen gas within the closed vessel 

 by connecting its platinum electrodes with the poles of a suitable 

 galvanic battery. We are thus able, by comparison, to ascertain 

 whether the addition of these gases and the other alterations in- 

 volved, exercise any appreciable efi'ect in hastening the process of 

 fermentation or in otherwise modifying its course or its products. 



From the few experiments which I have already made with the 

 view of throwing light upon this point, it would seem tliat the 

 addition of oxygen exercises the most marked influence when it is 

 allowed to operate in conjunction w^ith liquor potassse liberated 

 from its tube almost immediately afterwards. 



I have as yet made only a few experiments in which the in- 

 fluence of oxygen without liquor potassae was tested with acid 

 urine. In these, closed retorts were employed which had been 

 sealed after the fluids had been boiled for six minutes, oxygen was 

 liberated by electrolysis, and the vessels were subsequently kept 

 at 122° F. The results of the experiments were as follows : — 



In one of these trials with a urine whose spec. grav. was 1025, 

 and whose acidity was capable of being neutralized by five miuims 

 of liquor potassse to the ounce, the fluid became turbid after 

 the expiration of six hours, although, before the oxygen had been 

 liberated, this retort had been exposed to a temperature of 80°- 

 90° F. (21-26° C.) for eight days without its contained fluid under- 

 going any appreciable change. 



In three experiments with a specimen of urine whose specific 

 gravity was 1026, and whose acidity was equivalent to eight minima 

 of liquor potassse to the ounce, no general turbidity was noticed, 

 though towards the end of the second day a very distinct amount 

 of flocculent deposit was seen in each of the vessels*. On open- 

 ing one of these retorts at once (after shaking its contents), 

 Bacilli of difl'erent sizes, with progressive and rotatory movements, 

 were found, some of which had grown into filaments, though they 

 were not very numerous in each field. The fluid in the two other 

 retorts underwent no very appreciable change during the next 



* No cloudiness of the fluid had been produced during the process of 

 boiling. 



