THE USE OF BACTERIA IN THE ARTS. 63 



ferences in grades of tobacco grown in different 

 parts of the world are due solely to variations in 

 the curing processes and to the types of fermen- 

 tation. There are differences in the texture of 

 the leaves, differences in the chemical composi- 

 tion of the tobaccoes, which are due undoubtedly 

 to the soils and the climatic conditions in which 

 they grow, and these, of course, will never be af- 

 fected by changing the character of the ferment- 

 ative processes. It is, however, probable that in 

 so far as the flavours that distinguish the high and 

 low grades of tobacco are due to the character of 

 the fermentative processes, they may be in the fu- 

 ture, at least to a large extent, controlled by the 

 use of pure cultures in curing processes. Seem- 

 ingly, then, there is as great a future in the de- 

 velopment of this fermentative industry as there 

 has been in the past in the development of the 

 fermentative industry associated with brewing 

 and vinting. 



OPIUM. 



Opium for smoking purposes is commonly 

 allowed to undergo a curing process which lasts 

 several months. This appears to be somewhat 

 similar to the curing of tobacco. Apparently it 

 is a fermentation due to the growth of micro- 

 organisms. The organisms in question are not, 

 however, bacteria in this case, but a species of 

 allied fungus. The plant is a mould, and it is 

 claimed that inoculation of the opium with cul- 

 tures of this mould hastens the curing. 



TROUBLESOME FERMENTATIONS. 



Before leaving this branch of the subject it is 

 necessary to notice some of the troublesome fer- 



