SPONTANEOUS GENERATION. 567 



investigators. Its title was Heterogenie, and its author 

 was F. A. Pouchet, director of the Museum of Natural 

 History at Rouen. Ardent, laborious, learned, full not 

 only of scientific but of metaphysical fervor, he threw 

 his whole energy into the inquiry. Never did a subject 

 require the exercise of the cold, critical faculty more than 

 this one calm study in the unraveling of complex phe- 

 nomena, care in the preparation of experiments, care 

 in their execution, skillful variation of conditions, and 

 incessant questioning of results until repetition had placed 

 them beyond doubt or question. To a man of Pouchet's 

 temperament the subject was full of danger danger not 

 lessened by the theoretic bias with which he approached it. 

 This is revealed by the opening words of his preface: 

 " Lorsque, par la meditation, il fut evident pour moi que 

 la generation spontanee etait encore Fun des moyeus 

 qu'emploie la nature pour la reproduction des etres, je 

 m'appliquai a decouvrir par quels precedes on pouvait 

 parvenir a en mettre les phenomenes en evidence." It is 

 needless to say that such a prepossession required a strong 

 curb. Pouchet repeated the experiments of Schulze and 

 Schwann with results diametrically opposed to theirs. He 

 heaped experiment upon experiment and argument upon 

 argument, spicing with the sarcasm of the advocate the 

 logic of the man of science. In view of the multitudes 

 required to produce the observed results, he ridiculed the 

 assumption of atmospheric germs. This was one of his 

 strongest points. " Si les Proto-organismes que nous voyous 

 pulluler partout et dans tout, avaient leurs germes dis- 

 semines dans Fatmosphere, dans la proportion mathema- 

 tiquement indispensable a cot effet, Fair en serai t totalement 

 obscurci, car ils devraient s'y trouver beaucoup plus serres 

 que les globules d'eau qui forment nos linages epais. II 

 n'y a pas la la moindre exageration." Recurring to the 

 subject, he exclaims: "I/air dans lequel nous vivons aurait 

 presque la densite du fer." There is often a virulent con- 

 tagion in a confident tone, and this hardihood of argumen- 

 tative assertion was sure to influence minds swayed not by 

 knowledge, but by authority. Had Ponchet known that 

 " the blue ethereal sky " is formed of suspended particles, 

 through which the sun freely shines, he would hardly have 

 ventured upon this line of argument. 



Pouchet's pursuit of this inquiry strengthened the con- 



