42 DR. BASTIAN ON THE 



temperature of 212° JF- could be got over— if we could approxi- 

 mately calculate the degree of acidity of the fluid after exposure 

 to these conditions — the question would still remain whether the 

 urine had not altered in other important ways during the proba- 

 tion-period. The increased stability of the fluid previously re- 

 ferred to may not depend alone upon the conversion of some of its 

 urea into carbonate of ammonia, but in part upon other unknown 

 concurrent changes. So that even if we could add the potash 

 (through previous calculation) in suitable quantity, it would not 

 at all follow that it must necessarily exert so ready an influence 

 lipon this more stable fluid as it does upon urine just after it has 

 been boiled. Will future careful experiments tell us something 

 in regard to this part of the subject ? 



The question thus stated I have made some attempts to 

 answer ; that is, I have in part studied the effect of adding a quan- 

 tity of liquor potassse to a measured amount of sterilized urine of 

 known initial acidity, when the actual amount to be added is based 

 upon the consideration that the urine will have been heated to 

 212° E. for a prearranged time, and subsequently kept in an incu- 

 bator at a given temperature for a certain number of days. 



The results as yet have not been very satisfactory, since in 

 eighteen consecutive trials I only succeeded in inducing fermen- 

 tation ten times. 



The successes have been in cases in which after boiling in the 

 usual manner over the flame and in the can of boiling water, the 

 experimental vessel has been kept for 6-8 days at temperatures 

 between 70° and 80° F. before the liquor-potassse tube has been 

 broken, and when this tube has contained an amount of super- 

 heated potash equivalent to about one third of what would have 

 been required to neutralize the acidity of the urine employed 

 previous to boiling. 



The more the interval is prolonged, or the higher the incuba- 

 ting temperature during this interval, the less seems to be the 

 probability that fermentation can be induced. These, however, 

 are points which I intend to study further ; so that I will not go 

 into any minute details at present. 



It is only to be expected that a large number of failures 

 should be encountered at first in such experiments — where there 

 are so many changes to be taken into consideration, and where 

 much still remains to be learned. Even if a fairly accurate cal- 

 culation could be made as to the amount of alteration of the aci- 



