$4 ANIMALCULA OF INFUSIONS. I. 



tion that can apply) animalcula concentrated in 

 the germ, fupport a degree of cold they are in- 

 capable of when developed. 



Before terminating the chapter, fome reflec- 

 tions (hould be made on the fmaller fpecies of 

 animalcula which originate at freezing, — a phe- 

 nomenon not remarked in my DiiTertation, when 

 occafionally fpeaking of the feafon mofl fit for 

 their produdion, either becaufe I had not ad- 

 verted to the fadt, or had never obferved it. We 

 muft admit, that the germs of thefe moft minute 

 animalcula expand when no eggs will produce ; 

 for there is no inftance of any being hatched at 

 the freezing point. But there is nothing fmgular 

 in it, if we confider what is the temperature 

 we denominate freezing. The ancients believed 

 it the greateft pofTible degree of cold : modern 

 experiment has demonftrated how much it may 

 be augmented, either naturally or by art ; and 

 the fads we jufl now relate are an inconteflible 

 proof. They fliew, that the cold of freezing is 

 never feparate from a confiderable portion of 

 heat. Can we defire any thing more convincing ? 

 If the ball of a thermometer is transferred from, 

 a mixture of fnow and fait to plain fnow, it will 

 rife from 22° or 27° below zero to the freezing- 

 point again. Is not this a clear indication of the 

 thermometer palling from a cold to a warm fitua- 

 tion, or, to fpeak more philofophically, from a 



place 



