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specific HEAT.

EMILY.

I think that I have found a comparison for spe-cific heat, which is very applicable. Supposethat two men of equal weight and bulk, but whorequired different quantities of food to satisfytheir appetites, sit down to dinner, both equallyhungry; the one would consume a much greaterquantity of provisions than the other, in orderto be equally satisfied.

MRS. B.

Yes, that is very fair; for the quantity of foodnecessary to satisfy their respective appetites, va-ries in the same manner as the quantity of caloricrequisite to raise equally the temperature of dif-ferent bodies.

EMILY.

The thermometer, then, affords no indicationof the specific heat of bodies ?

MRS. B.

None at all: no more than satiety is a test ofthe quantity of food eaten. The thermometer,as 1 have repeatedly said, can be effected onlyby free or radiating caloric, which alone raisesthe temperature of bodies.

But there is another mode of proving the exis-tence of specific heat, which affords a very sa-tisfactory illustration of that modification. This