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A principal nfe of all thefe fa< 5 ls is, to explode the 
common theories of the generation of heat in animals. 
No attrition, no fermentation, or whatever elfe the me- 
chanical and chemical phylicians have devifed, can ex- 
plain a power capable of producing or deftroying heat, 
juft as the circumftances of the lituation require. A 
power of fuch a nature, that it can only be referred to 
the principle of life itfelf, and probably exercifed only 
in thofe parts of our bodies in which life feems pecu- 
liarly to relide. From thefe, with which no conftdera- 
ble portion of the animal body is left unprovided, the 
generated heat may be readily communicated to every 
particle of inanimate matter that enters into our com- 
pofttion. This power of generating heat feems to at- 
tend life very univerfally. Not to mention other Avell 
known experiments, Mr. hunter found a carp pre- 
ferve a coat of fluid water round him, long after all the 
reft of the water in the veflel had been congealed by a 
very ftrong freezing mixture. And as for infe6ts, Dr. 
MARTI NE obferved, that his thermometer, buried in 
the midft of a fwarm of bees, rofe to 97°. It feems ex- 
tremely probable, that vegetables, together with the 
many other vital powers which they poflefs in common 
%vith animals, have fomething of this property of gene- 
rating heat. I doubt, if the fudden melting of fnow 
which falls upon grafs, whilft that on the adjoining gra- 
vel walk continues fo many hours unthawed, can be ade- 
quately explained on any other fuppolition. Moift dead 
(g) EiTays Medical and Philofophical, p. 331. 
flicks 
