CONDITIONS FAVOURING FERMENTATION'. 



57 



Bacillus, however, is not the only organism to be met with in 

 boiled or superheated urine ; on rare occasions we may meet 

 with other forms. Thus, where oxygen has been added by elec- 

 trolysis, and where the reaction of the fluid has continued faintly 

 acid, I have on two or three occasions found Bacteria composed 

 of two little ovoid cells — something like B. termo, in fact, except 

 that they are always quite motionless. These have been in cases 

 where there has been a feeble fermentation of type (c) ; and in 

 some of my earlier experiments with results of the same kind 

 (though no oxygen was added), and where the incubating-tem- 

 perature was from 86°-95° F., I have found figure-of-8 Micrococci 

 together with short chaplets and small Torulae. Lastly, in one 

 or two specimens of partly neutralized diabetic urine with which 

 I experimented this spring, I found, some days after the boiling, 

 Torulae growing freely in the midst of flakes composed of aggre- 

 gated Bacilli. The odour of this fluid, when examined, was dis- 

 tinctly foetid ; and its reaction was neutral. As a rule, where well- 

 marked fermentation occurs in urine which has been almost neu- 

 tralized by potash, it is found at the time of examination to be 

 faintly alkaline, owing to the liberation of ammonia during the 

 process of fermentation. 



Where the fermentation takes place in superheated vessels 

 which have been sealed whilst the fluids were cold, so as to contain 

 air, the process is apt to show itself first by slight turbidity near, 

 the surface of the fluid. 



Hay -infusion, when treated in the manner last mentioned, 

 and when it is heated to 230° F. (110° C.) or upwards, is also 

 apt to show the change first at the surface of the fluid. When 

 heated to this temperature we do not, as a rule, get any very well- 

 marked turbidity. Nevertheless the fluid may grow perceptibly 

 clouded ; and whilst it becomes appreciably lighter in colour, a 

 flocculent precipitate gradually accumulates. In other cases we 

 may have whitish tufts of organisms manifesting themselves 

 and visibly increasing in size whilst the fluid around remains 

 clear. Lastly, in the least-satisfactory cases, we may have 

 neither of the foregoing signs of chauge, but only a slow accu- 

 mulation of a sedimentary matter, amongst which, in certain 

 cases, organisms are to be found that are unquestionably living. 

 Still it is also true that deposits of mere amorphous and crystal- 

 line matter will generally accumulate after a time at the bottom 

 of even a well-filtered hay-infusion, in cases in which no fermen- 



