sv.] SPONTANEOUS GENERATION. 349 



mentally. Here are dead animals, or pieces of meat, 

 says he ; I expose them to the air in hot weather, and 

 in a few days they swarm with maggots. You tell me 

 that these are generated in the dead flesh ; but if I put 

 similar bodies, while quite fresh, into a jar, and tie 

 some fine gauze over the top of the jar, not a maggot 

 makes its appearance, while the dead substances, never- 

 theless, putrefy just in the same way as before. It is 

 obvious, therefore, that the maggots are not generated 

 by the corruption of the meat ; and that the cause of 

 their formation must be a something which is kept 

 away by gauze. But gauze will not keep away aeri- 

 form bodies, or fluids. This something must, therefore, 

 exist in the form of solid particles too big to get 

 through the gauze. Nor is one long left in doubt what 

 these solid particles are; for the blowflies, attracted 

 by the odour of the meat, swarm round the vessel, and, 

 urged by a powerful but in this case misleading in- 

 stinct/ lay eggs out of which maggots are immediately 

 hatched upon the gauze. The conclusion, therefore, is 

 unavoidable ; the maggots are not generated by the 

 meat, but the eggs which give rise to them are brought 

 through the air by the flies. 



These experiments seem almost childishly simple, 

 and one wonders how it was that no one ever thought 

 of them before. Simple as they are, however, they are 

 worthy of the most careful study, for every piece of 

 experimental work since done, in regard to this subject, 

 has been shaped upon the model furnished by the 

 Italian philosopher. As the results of his experiments 

 were the same, however varied the nature of the ma- 

 terials he used, it is not wonderful that there arose in 

 Redi's mind a presumption, that in all such cases of 

 the seeming production of life from dead matter, the 

 real explanation was the introduction of living germs 



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