On the Power of Fluids to conduct Heat. 377 
it of different temperatures suffering it to stand, 
without agitation. He found that about 61b. of 
boiling hot water melted little more ice than as 
much water of 41°; and that by making such 
allowances as the experiments seemed to warrant 
for deductions when hot water was used, water of 
41°, or g° above the freezing point, melted quite 
as much, and often more, than the~hot water: 
From which he infers, that water, and by analogy 
all other fluids, do not transmit heat in the man- 
ner that solids do, but circulate it sae by the 
internal motion of their particles. 
The existence of this internal motion he has 
proved decidedly; that water of a certain tem- 
perature being of the greatest density, will always” 
take the Jowest place, and water either warmer or 
colder than that degree will ascend. This 
degree of greatest condensation he takes on the 
authority of others at 40°; it appears however 
from the experiment related above, to be still 
more favourable to his position, namely 42°: : 
-And that water of 32° must ascend till it comes 
to water of 53°, if it be not cooled in its pro- 
gress, which circumstance he admits. 
- Upon considering the facts related in his 
experiments therefore, there are three causes 
which suggest themselves as conspiring to cir- 
culate and diffuse the heat, by which the ice is 
melted, 
