BACTERIA IN RELATION TO 



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CHAPTER I 

 DEVELOPMENT OF SOIL BACTERIOLOGY 



BACTERIAL life probably antedates all other on this planet. 

 Walcott claims to have found fossil bacteria in geological 

 formations the age of which is estimated to be 33,000,000 years. 

 It is certain that they were the pioneers who gained a precarious 

 foothold on the bleak, primitive rock and manufactured acids 

 which in time produced an abode fit for the growth of higher 

 plants. Although bacteria were not known to man until the 

 perfecting of the compound microscope in the last quarter of the 

 seventeenth century, yet they manifested themselves centriries be- 

 fore. Even at the dawn of written history, decay, fermentation, 

 putrefaction, and disease were familiar phenomena, but varied 

 and interesting are the theories evolved to account for the ob- 

 served facts. 



Discovery of Bacteria. — Anton van Leeuwenhoek (1632- 

 1723), a Dutch linen-draper, often called the father of bacteri- 

 ology, during his life, contributed to the British Royal Society, one 

 hundred and twelve papers dealing with various scientific topics. 

 He also manufactured scores of microscopes many of which were 

 superior to any made before. With these he examined various 

 things — raindrops, saliva, and many putrefying substances. He 

 found in every case, living, moving animalcules which prior to his 

 time had been unrecognized. We can imagine his joy and sur- 

 prise from his statement: "I saw with wonder that my material 

 contained many tiny animals which moved about in a most amus- 

 ing fashion. The largest of these, A (Fig. i ) showed the live- 

 liest and most active motion, moving through the water or saliva 



