92

SPECIFIC HEAT.

ferent time they took in heating,proceeded merelyfrom their different conducting powers, they wouldeach have acquired an equal quantity of caloric.

CAROLINE.

Certainly. But how can you reverse this ex-periment !

MRS, B.

It may be done by cooling the several bodiesto the same degree in an apparatus adapted toreceive and measure the caloric which they giveout. Thus, if you plunge them into three equalquantities of water, each at the same tempera-ture, you will be able to judge of the relativequantity of caloric w r hich the three bodies con-tained, by that, which, in cooling, they commu-nicated to their respective portions of water; forthe same quantity of caloric which they eac h ab-sorbed to raise their temperature, will abandonthem in lowering it; and on examining the threevessels of water, you will find the one in whichyou immersed the lead to be the least heated ?that which held the chalk will be the next; andthat which contained the milk will be heated themost of all. The celebrated Lavoisier has in-vented a machine to estimate, upon this prin-ciple, the specific heat of bodies in a more per-fect manner; but I cannot explain it to you, tillyou are acquainted with the next mollification ofcaloric.