L ANIMALCULA OF INFUSIONS. I9 



the lower ; fome were in all the infufions. In 

 general, the hifling was heard on breaking the 

 feals, which proceeded from the violent efforts of 

 the air, rendered more elaftic, to efcape, as the 

 proofs already given convinced me, and an addi- 

 tional one occurred, than which nothing could 

 be more decifive. A fmall barometer was includ- 

 ed in a receiver full of common air ; whenever 

 the neck of a fealed veffel introduced by the top 

 was broke, the mercury rofe in the barometer. 

 To avoid redundancy, I may now remark, that 

 condenfation of the internal air almoft uniformly 

 manifefted itfelf in the other experiment witli 

 heat yet to be narrated. 



Veffels were immerfed feven minutes in boiling 

 water ; animalcula of the lower clafs appeared in 

 all fix ; and they conftantly originated though 

 the infufions remained twelve minutes in boihng 

 water. 



Perhaps it may be imagined that fome optical 

 illufion deceived me ; that I was induced to fup- 

 pofe the lower clafs of animalcula what arofe on- 

 ly from the particles of the infufed fubflances. 

 That it might be the confequence of decompofi- 

 teon by gradual fermentation, or by their lubrici- 

 ty occafioning locomotion on the leafl fiiock 

 or agitation ; or of an adive and volatile fpirit 

 penetrating and putting them in motion ; fi-om 

 a great evaporation, or one lefs copious ; from 

 B 2 2 



