1873 •] Atmospheric Life Germs. 227 



third with a platinum tube heated to redness. Between 

 the T tube, however, and the flask is a wide tube containing 

 a very narrow one within it, holding a plug of gun-cotton, 

 through which a large volume of air has been passed. The 

 tap in connection with the heated platinum tube was closed, 

 and the one in connection with the air-pump opened ; after 

 exhausting air was admitted through the red-hot platinum, 

 the tap was closed, and the air again pumped out, fresh air 

 being admitted through the heated tube ; this was repeated 

 three or four times. The stop-cocks were then closed, and 

 the sealed beak of the flask was broken within the india- 

 rubber connection ; the plug - of gun-cotton was shaken into 

 the liquid, after which the flask was sealed up again. All 

 experiments so performed resulted in the liquid, after three 

 or four days' exposure to a temperature of 25 to 30 C, 

 decomposing, and being found to contain bacteria, vibriones, 

 and fungi, just exactly like those in flasks exposed to ordinary 

 air. There was no difference in the length of time requisite 

 for the change, the forms of life occurring, or the nature of 

 the change resulting in flasks so treated, and those with the 

 same liquid exposed to common atmospheric air. These 

 experiments can scarcely be surpassed for beauty in their 

 arrangement, or for the importance and clearness of the 

 evidence they afford. Yet thinking that it might be objected 

 that the gun-cotton had given rise to the changes produced, 

 Pasteur made use of plugs of asbestos, and found a like 

 result ; but when the plugs of asbestos were heated red-hot 

 previous to being put into the flasks, the liquids remained 

 unchanged in every case, and so constantly and with such 

 perfect exactitude after an immense number of trials did 

 the results remain the same, that the experimenter himself 

 was astonished. 



Extension of previous results to other very alterable Liquids — 



Urine, Milk, and Albuminous Sugar Solution mixed with 



Carbonate of Lime. 



The facility with which urine exposed to the air becomes 



altered, and the change which takes place is well knowr. 



It becomes turbid and alkaline, sometimesfilled with bacteria, 



or covered with patches of mucor or Penicillhim glaucum. 



Often there is formed, when the temperature is not higher 



than 15 C, a pellicle consisting of a remarkable mucor 



closely resembling torula, but which is believed by Pasteur 



to be a different species. It consists of transparent cells, 



often without a nucleus, and considerably smaller than the 



cells of beer-yeast. There is also present in urine, when 



