On the Power of Fluids to conduct Heat. 385 
was ‘then set by in a still place for examina- 
tions | 
TEMPERATURE 
Time. at top. bottom. 
15 min, WJ a a7 
go 73 723 
45 68 673 
rth, — 64.8 64.6 
From all these experiments it is evident, 
_ that water has a proper. conducting power: In 
the last experiment, if the particles of water 
during the agitation had not actually communi- 
cated their heat, the hot ones ought to have 
Tisen to the top, and the cold ones subsided so 
as to have made a material difference in the 
temperature.—It is, however, equally evident, 
that water is a bad conductor of heat, probably as 
it is of electricity ; the descent of the heat in the 
second experiment is wonderfully slow ; a slight 
agitation for one second would do as much to 
induce the equilibrium as standing still one our. 
In repeating the third experiment, in a wine 
glass, I have several times known, water 3 an 
inch deeper to differ 50° in temperature from the 
‘Incumbent water. 
We must conclude, therefore, that the quick 
circulation of heat in water over.a fire, &c. is 
owing principally to the internal motion excited 
