CAROLINE.
It is then a mode of destroying the attraction of aggregation.
MRS. B.
Undoubtedly.—The two principal solvent fluids are water, and caloric. You may have observed that if you melt salt in water, it totally disappears, and the water remains clear, and transparent as before; yet though the union of these two bodies appears so perfect, it is not produced by any chemical combination; both the salt and the water remain unchanged; and if you were to separate them by evaporating the latter, you would find the salt in the same state as before.
EMILY.
I suppose that water is a solvent for solid bodies, and caloric for liquids?
MRS. B.
Liquids of course can only be converted into vapour by caloric. But the solvent power of this agent is not at all confined to that class of bodies; a great variety of solid substances are dissolved by heat: thus metals, which are insoluble in water, can be dissolved by intense heat, being first fused or converted into a liquid, and then rarefied into an invisible vapour. Many other bodies, such as salt, gums, &c. yield to either of these solvents.
CAROLINE.
And that, no doubt, is the reason why hot water will melt them so much better than cold water?