PRODUCED BY ALCOHOLIC FERMENTS. 161 



for the use of the autoclave, a modification of Papin's digester. 

 In this edition there are, however, two chapters which are 

 for us of still greater interest, one treating of wine, p. 131, 

 and the other of beer, p. 167. Appert states that in his 

 time the finest wines of France would not bear even a short 

 sea voyage ; some, indeed, were so easily spoilt that they 

 could not be exported at all, but had to be consumed at the 

 place where they were made. Appert treated these wines 

 as follows : The wine was drawn off into bottles which were 

 filled to the neck ; these were then hermetically closed and 

 the stoppers secured with iron wire ; a small air space was 

 left between the surface of the wine and the stopper. The 

 bottles were placed in a water bath, the temperature of which 

 was cautiously raised to 70. Some were then shipped to 

 St. Domingo, and on their return, after a lapse of two years, 

 they were examined. For comparison he had set apart some 

 bottles of the same wine, but which had not been heated. 

 The latter had a disagreeable taste, whilst the wine which 

 had been heated proved highly satisfactory in every respect. 

 His experiments thus showed that a wine, which under 

 ordinary circumstances would not stand a journey, had in 

 this case borne the voyage without any ill-effects whatever. 

 He was, therefore, justified in pointing out the great benefit 

 which his method would bring to France in that it would 

 render possible the exportation of the fine wines of the 

 country to the most distant regions of the earth. He also 

 submitted beer to the same treatment, and obtained a similar 

 favourable result. 



Appert was not able to give an explanation of what 

 actually took place on heating, and he did not get further 

 than to perceive that it was the " principle of fermentation " 

 which was destroyed. He saw, that neither fermentation 

 nor putrefaction took place in the substances which he 

 submitted to the action of heat. It was only after 

 Cagniard Latour and Schwann had shown that fermen- 



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