72 ORIGINATION OF LIVING BEINGS. 



words. You are all of you aware of the phenomena 

 of what is called spontaneous generation. Our fore- 

 fathers, down to the seventeenth century, or there- 

 abouts, all imagined, in perfectly good faith, that 

 certain vegetable and animal forms gave birth, in the 

 process of their decomposition, to insect life. Thus, if 

 you put a piece of meat in the sun, and allowed it to 

 putrefy, they conceived that the grubs which soon 

 began to appear were the result of the action of a 

 power of spontaneous generation which the meat con- 

 tained. And they could give you receipts for making 

 various animal and vegetable preparations which would 

 produce particular kinds of animals. A very distin- 

 guished Italian naturalist, named Redi, took up the 

 question, at a time when everybody believed in it; 

 among others our own great Harvey, the discoverer 

 of the circulation of the blood. You will constantly 

 find his name quoted, however, as an opponent of the 

 doctrine of spontaneous generation ; but the fact is, 

 and you will see it if you will take the trouble to look 

 into his works, Harvey believed it as profoundly as 

 any man of his time ; but he happened to enunciate 

 a very curious proposition — that every living thing 

 came from an egg ; he did not mean to use the word 

 in the sense in which we now employ it, he only 

 meant to say that every living thing originated in a 

 little rounded particle of organized substance • and it 

 is from this circumstance, probably, that the notion of 

 Harvey having opposed the doctrine originated. Then 

 came Redi, and he proceeded to upset the doctrine in a 

 very simple manner. He merely covered the piece of 



