1^7 2 ANIMALCULA OF INFUSIONS. U 



doubt that my reveries may lead thofe readers in- 

 to error who have too great an opinion of my 

 /feeble meditations, and my trivial writings in ge- 

 neral. From your anfwer of 24 March, I per- 

 ceive you had the fame doubt as M. de Sauf- 

 fure. ' The fads you colled,* you obferve, 

 ^ prove, without reply, the extreme tranfparency 

 "^ of thefe germs. The heating of bodies by the 

 ■^ rays of the fun, which is always reciprocally in 

 ^ proportion to their tranfparency, perfuades us 

 ^ that the heat freely paifes through the germs 

 '^ without altering their flrudlure. But this per- 

 *^ fuafion would become much ftronger, if we 

 ' could prove diredly that it is the fame with 



* our fire as v/ith the folar rays.* What you 

 add immediately afterwards excites my admi- 

 ration. ' It feems that a courfe of experiments 



* on this point would be of the firft importance, 

 "^ and your excellent conjecture might be ex- 

 "^ pofed to other trials : to examine whether cer- 



* tain infedls which are very tranfparent would 

 "^ fupport the adion of heat better than thofe 

 ' which are very opaque. Among the animalcula 

 ^ of infufions are fome wliofe tranfparency is al- 

 ' moil infinitely greater than thofe of others. Per- 

 ' haps there might be foundation for fuppofing, 



■^ according to your principle, that heat has lefs 

 *^ influence on the former than the latter. It is 

 ^ true, I have faid in my letter, that animalcula 



* in. 



