[ 467 3 
in this degree of heat? Is it that fire as it pafTes into 
fbme bodies becomes latent, agreeable to a do 6 trine which 
has for fome time been taught at Edinburgh by Profefibr 
BLACK ? Or does fire become fixed and qukfeent^ accord- 
ing to a fimilar fyftem adopted by Dr. franklin ? Air 
we know exifts either in a fixed or elaflic hate ; and fire 
may in like manner exift in bodies, either in a latent, 
fixed, and quiefcent\ or in a fenfible, fluid, and aftive 
hate. Agreeable to this idea, the bees wax receives 
the hre in an active hate, and dihblves ; while the hu- 
man body and the albu7nen ovi, receiving the hre in a 
latent hate, are little altered in their temperature. Let 
each of thefe, however, be put in contadl with a different 
body, tin for inhance; and though the heat of the air 
continues the fame, yet the hre no longer enters in a la- 
tent hate, but wdth all its fenhble and adtive powers ; for 
the albumen ovi fufpended in a tin veffei foon coagulates ; 
and the human body, covered with the fame metal, would 
quickly experience an intolerable and dehrudtive degree 
of heat. Or are the above phaenomena more fatisfac- 
torily explained, by conhdering different bodies as pof- 
fehing different conducting powers ;; fome being hrong, 
others weak conductors of hre? All thofe bodies 
then which are weak conductors of hre from air, may 
be placed in air, without receiving the heat of this me- 
dium. Hence the albumen ovi remains fluid in air heated 
to 224 °. Hence likewife the frog, the lizard, the came- 
lion,. 8 cc. retain their natural temperature, and feel cold 
[l) Exper. and Obferv. p. 346,, and 412.. 
to 
