^dS ANIMALCULA OF INFUSIONS, t*, 



What happens fo much at large in the chicken 

 probably palTes in infinite miniature among our 

 infufion animalcula. They feed ; they/xpand by 

 nutrition ; and the more nutriment they take, the 

 more is theii* tranfparency leflened, but it is never 

 entirely dellroyed. Their delicate veflels do not 

 admit particles fufficiently grofs or homogeneous 

 to accomplifh this. Thofe affimilated are propor- 

 tioned to its extreme finenefs (i). 



While animalcula of the lower orders remain 

 in their original ftate of germs, their tranfparen- 

 cy is probably fo complete that light or heat tra- 

 %erfes them without impreflion. It may be pof= 

 fible that the germs are fo fmall as to admit only 

 one or two rays of light. But when expan- 

 fion commences, they begin to aflimilate foreign 

 particles with themfelves. The aflbciation of 

 thefe with the elements of the texture tends 

 more or lefs to diminilh the tranfparency, Confe- 

 quently to allow more influence to light or heat. 

 It is nearly the fame as with air, which, being 



condenfed 



( I ) The patts of many animals are never expanded b^ 

 nutrition. There is hardly an infedl known that grows 

 after its laft metamorphofis ; and if any do fo, their in- 

 crement is too fudden to arife from nutrition. A cater* 

 pillar feeds voracioufly on leaves : Its fize rapidly in- 

 creafes : it changes to a butterfly, which lives on the 

 purefl neftar of flowers ; but increment is at an tnd* 

 ~T. 



