64 STUDIES OX FERMENTATION. 



conditions in such a way as would cause it to succeed or fail, 

 according to the circumstances of the manipulation emplo3'ed. 



On December 7th, 1874, we took two bottles of must which 

 we had preserved, after Appert's process, in our laboratory 

 from the beginning of October, 1873. Both of these were 

 covered with dust — the dust that floated about in our labora- 

 tory. We decanted them as follows : — One bottle, which we 

 handled without special precautions, we uncorked by means of 

 an ordinary corkscrew, and decanted into another bottle that 

 had been well waslied, as bottles are washed when they are to 

 be used subsequently. This bottle was taken from a number 

 that had been standing upside down on a drainer for a fortnight. 

 We took no precaution to remove the dust which covered the 

 exterior of the bottle of must, or to purify the washed bottle. 

 The second bottle of must, on the other hand, was decanted 

 after we had removed the dust that covered it ; its cork was 

 cut off close to the string, and the flame of a spirit lamp was 

 passed over the string and the surface of the cork ; and, as a 

 final precaution, the corkscrew was passed through the flame. 

 As for the bottle into which we subsequently decanted the 

 must, we first plunged it in a hot- water bath kept at 100° C. 

 (212° F.), then took it into a garden to cool upside down in the 

 open air. After these precautions we removed it, and imme- 

 diately decanted into it the must from the second bottle. 



The first bottle showed signs of growths, both on the surface 

 and at the bottom of the must, the day after the operation, and 

 manifested the first symptoms of alcoholic fermentation on 

 December 16th. The contents of the second bottle remained 

 perfectly unchanged after being exposed to the warmth of a 

 stove for several months. 



Can anything be more conclusive than these facts ? They 

 are in perfect keeping with the views that wo have recently 

 expressed, and with the principles that we have maintained for 

 nearly twenty 3^cars, on the subject of the causes of change in 

 organic liquids. 



It is by no means our intention to assert that in the atmo- 



