SCIENCE IN ITS APPLICATION. 101 



in course of half a week and, at three feet, a tempera- 

 ture of 129 F. It is needful to cover the heap with 

 cloths to absorb the condensing moisture, which would 

 otherwise condense in the upper layers of tobacco, and 

 cause rotting and molding. Smoking tobacco is not to 

 be allowed to heat above 122 F. Behrens believes that 

 these changes are to be ascribed chiefly to the action of 

 anaerobic ferments, although a local action of aerobic 

 forms at the same time is not excluded. He found in 

 sweated tobacco vigorous individuals of the widely dis- 

 tributed aerobic form, Bacillus subtilis, and also an 

 aerobic Clostridium, which, like Clostridium butyricum, 

 formed endospores. He does not think the latter espe- 

 cially active, but recalls the fact that Cohn attributes the 

 fermentation or spontaneous heating of damp hay and 

 stable manure to the former organism. Behrens* also 

 states that he lias found the mold, Aspergillus fumi- 

 qatus in sweating tobacco, upon six out of eight samples 

 from three different dealers. While this organism is 

 regarded by Cohn as the cause of the heating of piled- 

 up malt, it is not supposed to play any large part in the 

 sweat. 



Behrens endeavored to ascertain the changes which 

 occur during sweating. He found a loss of only 2.5 to 

 5.6 per cent of dry matter, although others put it as 

 high as eight to twelve per cent in the latter case, the 

 loss of water is included. This loss falls chiefly upon 

 the soluble carbohydrates and less upon the non-volatile 

 organic acids. There is no loss of nitrogen, yet one- 

 third of the nicotine disappears; it possibly serves as 

 food for the lower organisms, as an earlier research f 

 has shown that Botrytis cinerea can eat it. There is a 

 loss of nitrate nitrogen and a diminution of the other 



* Centralblatt fur Bakteriologie und Parasitenkunde, 11 (1894) p. 



* Zeitschr. f. Pflanzenkrankheiten, 3 (1893), pp. 85-86. 



