10 Experiments on the 
further accession of heat is appreciable by the 
thermometer. 
In attending to the progress of the preced- 
ing experiments, I observed that when the 
steam was let off from the boiler, at a high 
temperature, it passed into the worm with 
great rapidity, and more water was condensed 
in the same space of time than when the 
steam was sent over at the common boiling 
temperature. Also, when the steam at high 
temperature was suffered to pass freely through 
the stop-cock, the thermometer in the boiler 
began to sink with considerable rapidity.— 
From these circumstances, it is evident, that 
the steam of high temperatures is more dense 
than that which proceeds from common boil- 
ing water; that a greater quantity of it is 
compressed into a less space ; and the increase 
of force, occasioned by the increase of tem- 
perature, no doubt proceeds chiefly, if not 
wholly, from this increased density of the 
steam, by new generation, and not at. all 
from any additional combination of the pre- 
viously existing steam with latent heat. It is 
a well-known law, with respect to atmospheric 
air, that doubling the pressure, doubles the 
density ; but whether this law holds good with 
respect to steam (so that double the quantity 
compressed into the same space is requisite to 
