ORIGINATION OF LIVING BEINGS. 71 



tion, 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 cu- 

 rious 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 par- 

 ticle of organized substance ; and it is from this cir- 

 cumstance, 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 meat with 

 some very fine gauze, and then he exposed it to the 

 same conditions. The result of this was that no grubs 

 or insects were produced ; he proved that the grubs 

 originated from the insects who came and deposited 

 their eggs in the meat, and that they were hatched 

 by the heat of the sun. By this kind of inquiry he 

 thoroughly upset the doctrine of spontaneous genera- 

 tion, for his time at least. 



Then came the discovery and application of the 

 microscope to scientific inquiries, which showed to 

 naturalists that besides the organisms which they 

 already knew as living beings and plants, there were 

 an immense number of minute things which could be 

 obtained apparently almost at will from decaying vege- 

 table and animal forms. Thus, if you took some or- 

 dinary black pepper or some hay, and steeped it in 



