Yes; hence you may judge how little the sense of feeling is to be relied on as a test of the temperature of bodies, and how necessary a thermometer is for that purpose.
It has indeed been doubted whether fluids have the power of conducting caloric in the same manner as solid bodies. Count Rumford, a very few years since, attempted to prove, by a variety of experiments, that fluids, when at rest, were not at all endowed with this property.
CAROLINE.
How is that possible, since they are capable of imparting cold or heat to us; for if they did not conduct heat, they would neither take it from, nor give it to us?
MRS. B.
Count Rumford did not mean to say that fluids would not communicate their heat to solid bodies; but only that heat does not pervade fluids, that is to say, is not transmitted from one particle of a fluid to another, in the same manner as in solid bodies.
EMILY.
But when you heat a vessel of water over the fire, if the particles of water do not communicate heat to each other, how does the water become hot throughout?
MRS. B.
By constant agitation. Water, as you have seen, expands by heat in the same manner as solid bodies; the heated particles of water, therefore, at the bottom of the vessel, become specifically lighter than the rest of the liquid, and consequently ascend to the surface, where, parting with some of their heat to the colder atmosphere, they are condensed, and give way to a fresh succession of heated particles ascending from the bottom, which having thrown off their heat at the surface, are in their turn displaced. Thus every particle is successively heated at the bottom, and cooled at the surface of the liquid; but as the fire communicates heat more rapidly than the atmosphere cools the succession of surfaces, the whole of the liquid in time becomes heated.