THE QUESTION OF SPONTANEOUS 

 GENERATION. 



' ALL dry bodies,' said Aristotle, ' which become damp, 

 and all damp bodies which are dried, engender animal 

 life.' Bees, according to Virgil, are produced from 

 the corrupted entrails of a young bull. At the time 

 of Louis XIV. we were hardly more advanced. A 

 celebrated alchemist doctor, Van Helmont, wrote : 

 ' The smells which rise from the bottom of morasses 

 produce frogs, slugs, leeches, grasses, and other 

 things.' But most extraordinary of all was the true 

 recipe given by Van Helmont for producing a pot 

 of mice. It suffices to press a dirty shirt into the 

 orifice of a vessel containing a little corn. After about 

 twenty-one days, the ferment proceeding from the dirty 

 shirt modified by the odour of the corn effects the trans- 

 mutation of the wheat into mice. Van Helmont, who 

 asserted that he had witnessed the fact, added with 

 assurance : 



' The mice are born full grown ; there are both 



