25G PASTEUR, OX FERMENTS. 



" milk" and " urine." The details' of the results derived 

 from these two fluids will show, as I hope, the kind of 

 future in store for this department of study. 



I introduce about 100 cubic centimeters of recent urine 

 into a flask capable of containing 250 cubic centimeters. 

 The drawn-out neck of the flask communicates with a 

 platinum tube, heated to redness. The liquid is made to boil 

 for two or three minutes, and then allowed to cool. When 

 refilled with air, which has been subjected to a red heat, the 

 flask is hermetically closed. 



The flask, under these conditions, may remain for an inde- 

 finite time in a stove, at a temperature of 30° C, without 

 its undergoing any alteration. After the lapse of a month 

 or six weeks, I cause a small quantity of amianthus charged 

 with the atmospheric dust to fall into the flask, the mode in 

 which this is effected being precisely that described in the 

 ' Comptes Rendus' of the 6th of February. The neck of the 

 flask being then again hermetically closed, the apparatus is 

 replaced in the stove. 



In order to be sure that the manipulation to which the 

 flask is submitted, for the introduction of the atmospheric 

 dust, does not itself in any way affect the result of the 

 experiment, I prepare a second flask similar to the other; 

 only that, instead of allowing amianthus charged with 

 atmospheric dust to fall into it, I substitute the same amian- 

 thus previously calcined for some moments before its intro- 

 duction into the flask. 



The following are the constant results of the experiments 

 so made. 



The fluid in the flask which has received the amianthus 

 deprived of the atmospheric dust remains unaltered at the 

 temperature of 30° C, whatever may be the duration of its 

 exposure to this heat, which is so favorable to the putrefac- 

 tion of urine. On the contrary, at the end of six hours, 

 the urine which has received the atmospheric dust, presents 

 organized products — Mucedinea or Infusoria. Among the 

 latter I have noticed chiefly Bacteria, very minute Vibr%one» t 

 and Monads, in fact, the same Infusoria that I have found in 

 the same urine exposed to the contact of the atmospheric air 

 at a temperature of 30° C. During the following days will 

 be witnessed an abundant deposition of crystals of ammo- 

 niaco-magnesian phosphates and of the alkaline lithates. 

 The urine becomes more and more ammoniacaL Its urea 

 disappears under the influence of the true ferment of the 

 urine, a ferment which I have proved to be organized, and 

 whose germ could only have been introduced in the atmo« 



