CAROLINE.
It must be, no doubt, the extrications of latent heat, at the instant the water freezes, that raises the temperature.
MRS. B.
Certainly; and if you now examine the thermometer, you will find that its rise was but temporary, and lasted only during the disengagement of the latent heat—now that all the water is frozen it falls again, and will continue to fall till the ice and mixture are of an equal temperature.
EMILY.
And can you show us any experiments in which liquids, by being mixed, become solid, and disengage latent heat?
MRS. B.
I could show you several; but you are not yet sufficiently advanced to understand them well. I shall, however, try one, which will afford you a striking instance of the fact. The fluid which you see in this phial consists of a quantity of a certain salt called muriat of lime, dissolved in water. Now, if I pour into it a few drops of this other fluid, called sulphuric acid, the whole, or very nearly the whole, will be instantaneously converted into a solid mass.
EMILY.
How white it turns! I feel the latent heat escaping, for the bottle is warm, and the fluid is changed to a solid white substance like chalk!