72 ORIGINATION OF LIVING BEINGS. 



water, you would find in the course of a few days that 

 the water had become impregnated with an immense 

 number of animalcules swimming about in all direc- 

 tions. From facts of this kind naturalists were led to 

 revive the theory of spontaneous generation. They 

 were headed here by an English naturalist, — Needham, 

 — and afterwards in France by the learned Buffon. 

 They said that these things were absolutely begotten 

 in the water of the decaying substances out of which 

 the infusion was made. It did not matter whether you 

 took animal or vegetable matter, you had only to steep 

 it in water and expose it, and you would soon have 

 plenty of animalcules. They made a hypothesis about 

 this which was a very fair one. They said, this matter 

 of the animal world, or of the higher plants, appears to 

 be dead, but in reality it has a sort of dim life about it, 

 which, if it is placed under fair conditions, will cause it 

 to break up into the forms of these little animalcules, 

 and they will go through their lives in the same way as 

 the animal or plant of which they once formed a part. 



The question now became very hotly debated. 

 Spallanzani, an Italian naturalist, took up opposite 

 views to those of Needham and Buffon, and by means 

 of certain experiments he showed that it was quite pos- 

 sible to stop the process by boiling the water, and clos- 

 ing the vessel in which it was contained. " Oh ! " said 

 his opponents ; " but what do you know you may be 

 doing when you heat the air over the water in this way ? 

 You may be destroying some property of the air requi- 

 site for the spontaneous generation of the animalcules." 



However, Spall anzani's views were supposed to be 

 upon the right side, and those of the others fell into 

 discredit ; although the fact was that Spallanzani had 



