INFUSORIAL ANIMALCULES. 35 



scientific men should be more than sceptical upon this 

 point, cannot be wondered at ; and were it not that the 

 notion originated with, and the experiments have been 

 conducted by, one who holds a most honourable position 

 amongst us, it would not have been entertained for a 

 moment. That some mistake exists with respect to com- 

 municating vitality to matter, by this means, there cannot 

 be a doubt. 



It is not surprising that Linneus, with the imperfect 

 microscopes of his day, should mistake Infusorial animal- 

 cules for minute drops of oil in the water; but that 

 Dutrochet, so late as 1833, should publish to the world 

 that all the globular and elliptical Infusoria were vesicles 

 set in motion by streams of electricity, and therefore could 

 be artificially produced, is but another exemplification of the 

 fact, that men of the most distinguished talents in one 

 department of science may form very erroneous notions 

 on others, especially where long continued observations, 

 and very accurate perceptions, are indispensable for arriv- 

 ing at right conclusions respecting them. 



In 1834, Cagniard Latour made a public declaration, 

 that he had manufactured animalcules by the aid of car- 

 buretted hydrogen. This assertion led to an examination, 

 subsequently, of the creatures, by M. Audouin, who 

 ascertained them to be a species of the Entomostracea, 

 and who did not hesitate to pronounce the method, by 

 which they were said to have been produced, to be 

 fallacious. 



The most ingenious experiment on the imaginary pro- 

 duction of Infusoria is that of Professor BonsdorfFs, 

 which he communicated to the German Naturalists' Asso- 



D 2 



