Dr. J. Sack 139 



however, was first necessary in order to decide 

 this positively. 



For this purpose four baskets were taken, 

 each filled with 7 kilos of cacao. These 

 baskets were placed upon stones to allow the 

 liquor to drain away. 



To the baskets Nos.- i and 2 nothing further 

 was added; to the contents of basket No. 3 was 

 added a certain quantity of formaldehyde, and 

 to the contents of basket No. 4 some chloroform. 

 Now formaldehyde and chloroform are both 

 substances which exercise a stupefying or even 

 deadly effect upon all forms of life, but do not 

 disturb chemical combinations ; therefore, if 

 the fermentation is due to a chemical process, 

 the temperature in the four baskets would have 

 risen to the same level ; and if to a biological 

 process then in that case the temperature in 

 baskets Nos. i and 2 would have risen, and that 

 in baskets Nos. 3 and 4 would have remained 

 at the level of the surrounding atmosphere. 



In process of time the temperature in baskets 

 Nos. i and 2 rose to 40 C., while that in baskets 

 Nos. 3 and 4 remained at the level of the sur- 

 rounding atmosphere, that is to say 28 C. In 

 baskets Nos. t and 2, where the fermentation 

 was thus in full operation, some chloroform' was 

 placed, as a further proof, whereupon the 

 temperature after some hours dropped from 

 40 C. to 28 C., and fermentation ceased. 



From this test it thus follows that the fer- 

 mentation of the cacao beans is not due to a 

 chemical but to a biological process. 



