On the Conduction of Water. 153 
change of particles would permit further rise of the thermometer, 
and soon cause it to fall 
In the next place, vihen poured on the thermometer, situated as be- 
fore, was set on fire. The thermometer rose to 36°, and once to 
38°, when a greater quantity was burned. The ice was melted more 
rapidly than in the preceding experiments, because the flame acted 
on a greater surface of ice. Soon after the combustion ceased, the 
thermometer began to descend. 
In the next pine; the hollow in the ice was so enlarged, as to per- 
mit a pound weight of red hot iron to be held over the bulb of the 
thermometer placed one fourth of an inch under the surface. The 
thermometer soon rose above 36°, while the ice was rapidly mel- 
ted; the continuance of the iron did not increase the temperature 
of the bulb, and as soon as the iron was removed, the thermome- 
ter began to fall. 
All these experiments lead to the same conclusion as the first. 
In the last place, the thermometer was immersed in water in an 
earthen dish, at the temperature of 58°, and half an inch deep over 
the bulb, and the bulb was placed two inches from the outer edge of 
the water. Oil at the temperature of 280° was then poured care- 
fully on the surface, and at the other end of the thermometer. The 
thermometer rose slowly, as the oil floated over the bulb, more than 
12°, or a little above 70°. 
Bos the first three sets of experiments it results, if water ex- 
pands below 40°, that the rise of the thermometer was owing to the 
descent of the heated but heavier particles of water, unless a part of 
the effect is to be attributed to the radiation of the caloric through 
the water to the bulb, and its absorption by the bulb. 
Experiments similar to the last, have often shown that water does 
conduct caloric downwards from particle to particle, except such 
part of the effect as may be supposed to result from radiation as be- 
fore stated. For it can scarcely be believed that in such experi- 
ments, the caloric passes by and along the vessel to the thermometer. 
The mixture of cold and hot water, and the almost instantaneous re- 
duction of temperature from 40° or 60° to 150° or 180°, according 
to the relative quantity and temperature of the water employed, is 
proof incontrovertible of the conduction of caloric from particle 
to particle in any direction. This fact is a most benevolent pro- 
Vision in the constitution of water, and it is so well known to the 
learned and ignorant, that it is amazing Count Rumford should have 
Vol. XX VIII.—No. 1. 20 
