60 THE STORY OF GERM LIFE. 



appear to be produced by micro-organisms of 

 different sorts. During the fermentation which 

 follows the drying the producer has to contend 

 with micro-organisms that are troublesome to him ; 

 for unless the phenomena are properly regulated 

 the fermentation that occurs produces effects 

 upon the tobacco which ruin its character. From 

 the time the tobacco is cut until the final stage 

 in the curing the persons engaged in preparing 

 it for market must be on a constant watch to 

 prevent the growth within it of undesirable or- 

 ganisms. The preparation of tobacco is for this 

 reason a delicate operation, and one that will be 

 very likely to fail unless the greatest care is taken. 

 In the several fermentative processes which 

 occur in the preparation there is no question that 

 micro-organisms aid the tobacco producer and 

 manufacturer. Bacteria produce the first fermen- 

 tation that follows the drying, and it is these or- 

 ganisms too, in large measure, that give rise to 

 all the subsequent fermentations, although seem- 

 ingly in some cases purely chemical processes 

 materially aid. Now the special quality of the 

 tobacco is in part dependent upon the peculiar 

 type of fermentation which occurs in one or an- 

 other of these fermenting actions. It is the fer- 

 mentation that gives rise to the peculiar flavour 

 and to the aroma of the different grades of tobacco. 

 Inasmuch as the various flavours which charac- 

 terize tobacco of different grades are developed, 

 at least to a large extent, during the fermentation 

 processes, it is a natural supposition that the dif- 

 ferent qualities of the tobacco, so far as concerns 

 flavour, are due to the different types of fermen- 

 tation. The number of species of bacteria which 

 are found upon the tobacco leaves in the various 



