.24 ANIMALCULA OF INFUSIONS. I»- 



the non-exiftence of thefe animalciila does not 

 depend on the duration of time, but entirely on 

 the aclion of the heat to which infufions have 

 been expofed. 



Before terminating the experiments before us, 

 and making the reflections which they merit, let 

 a word be faid, in pafling, of the death of ani<- 

 malcula, after fpeaking fo largely of their birth. 

 We have feen the lower clafs originate, in clofe 

 Tefiels, at 212° ; while the higher fcarcely can 

 at 93°. It v^^ould therefore appear, that, on ex- 

 pofmg both to heat, the lower clafs Ihould refiil 

 it much better than the higher : however, the 

 fame degree that is fatal to the one, is fatal to 

 the other ; and both conflantly die at io6°, oVy 

 at moil, io8°. 



Two important confequences flow from thefe 

 experiments : Firfl:, The efEcacy of heat in ren- 

 dering clofe infufions barren of an infinity of 

 animated beings. In open infufions, are an in- 

 credible number and variety j while in the clofe, 

 fubje£ted to the afticn of fire, one feeks in vain 

 for an animal which he can call even the fmall^ 

 eft in fize. We cannot afSrm, that fimpie inclu- 

 fion occafions fuch devaftation, fmce, in other 

 cafes, it only diminiihes the number : therefore, 

 we muft conclude, that heat truly does it. But 

 how can it operate ? Can we think it is by^ 

 rendering infufed fubilances unfit for producing 



animalcula ?;' 



