8 AGRICULTURAL BACTERIOLOGY 



Decomposition and its cause. From 1683 to 1850 little 

 was learned concerning the importance of the bacteria in 

 nature. The biologists of those days were more interested 

 in classifying and naming the various plants and animals 

 than in studying what they were able to do. They were 

 interested in morphology rather than in physiology. 



It had been known to man ever since he attempted to 

 preserve plant or animal matter that change in it was in- 

 evitable. The microscope revealed in decomposing material 

 an immense number of microorganisms, among which the 

 bacteria predominated. It was believed by many that these 

 organisms were the cause of the decomposition. Justus yon 

 Liebig, the founder of organic and agricultural chemistry, 

 believed that decomposition was purely a chemical process 

 that in some way occurred in matter brought in contact with 

 the decomposing material. He was the dominant figure in 

 the chemical world from 1840 to 1860, and when he stated 

 that " those who pretend to explain the putrefaction of 

 animal substances by the presence of microorganisms reason 

 very much like a child who would explain the rapidity of 

 the Rhine by attributing it to the violent motion imparted 

 to it in the direction of Bingen by the numerous wheels of 

 the mills of Mayence," there were few bold enough to con- 

 tradict him, and none whose reputation carried conviction. 



Spontaneous generation. Numerous experiments had 

 shown that an infusion of meat could be boiled for some 

 time and sealed immediately thereafter in the vessel in 

 which it had been heated, and yet it would often undergo de- 

 composition, and would be found teeming with microscopic 

 life. Such experiments had given rise to what seems now 

 a curious theory, that of spontaneous generation of life ; 

 that is, the creation of life from dead matter. The scien- 

 tists of those days could not imagine that any living form 

 could endure the temperature of boiling water for even the 



