Conversations on Chemistry, V. 1-2 / In Which the Elements of that Science Are Familiarly Explained and Illustrated by Experiments

by Mrs. Marcet

Quite warm I declare! this is a most curious experiment of the disengagement of latent heat.

MRS. B.

The slakeing of lime is another remarkable instance of the extrication of latent heat. Have you never observed how quick-lime smokes when water is poured upon it, and how much heat it produces?

CAROLINE.

Yes; but I do not understand what change of state takes place in the lime that occasions its giving out latent heat; for the quick-lime, which is solid, is (if I recollect right) reduced to powder, by this operation, and is, therefore, rather expanded than condensed.

MRS. B.

It is from the water, not the lime, that the latent heat is set free. The water incorporates with, and becomes solid in the lime; in consequence of which, the heat, which kept it in a liquid state, is disengaged, and escapes in a sensible form.

CAROLINE.

I always thought that the heat originated in the lime. It seems very strange that water, and cold water too, should contain so much heat.

EMILY.