52 BACTERIA. 



animalculae or germs, and pushing the theory to its 

 legitimate and logical conclusion, he also evolved a germ 

 theory of putrefaction and fermentation. He maintained 

 that air, water^ vinegar, fermenting wine, old beer, and sour 

 milk, were all full of germs ; that the blood and pustules of 

 smallpox also contained them, and that other diseases, very 

 rife about this period, were the result of the activity of these 

 organisms. Such headway did he make, and such conviction 

 did his arguments carry with them, that the mercurial 

 treatment much in vogue at that time was actually based on 

 the supposition that these organisms, the causm causantes of 

 disease, were killed by the action of mercury and mercurial 

 salts. 



With a kind of prophetic instinct, and certainly as the 

 result of keen observation, Varro and Lancisi ascribed the 

 dangerous character of marsh or swamp air to the action of 

 invisible animalculae ; in fact the theory was so freely and 

 forcibly propagated that even where no micro-organisms 

 could be found their presence was inferred, with the inevi- 

 table result, asLoffler points out, that these "inconceivable" 

 worms became the legitimate butts for the shafts of ridicule ; 

 and in 1726 there appeared in Paris a satirical work, in 

 which these small organisms received the name of "fainter," 

 " body-pincher," " ulcerator," " weeping fistula," " sensual- 

 ist ; " the whole system was thus laughingly held up to 

 satire, and the germ theory of disease completely dis- 

 credited. Linnaeus, however, with his wonderful powers of 

 observation and deduction, considered that it was possible 

 that there might be rescued from this "chaos" small living 

 beings which were as yet insufficiently separated and ex- 

 amined, but in which he firmly believed might lie not only the 

 actual contagium of certain eruptive diseases, and of acute 

 fevers, but also the exciting causes of both fermentation and 

 putrefaction. 



The man, however, who of all workers earliest recognized 

 the importance of Linnaeus' observations was a Viennese 

 doctor, Marcus Antonius Plenciz, who with great shrewd- 

 ness recognized the prime importance of these organisms 

 in connection with the etiology not only of contagious 

 diseases, but also of putrefaction. He it was who, at this 

 time, insisted upon the specific character of the infective 

 agent in every case of disuse : for scarlet fever there was a 



