e
latent?"

"Why, the word heat has two meanings, uncle. In the first place, it
means hotness. Hotness can not be latent, as the clown finds when he
pockets the poker. In the second place, heat means a something the
nature of which we don't know, which is the cause of hotness, and also
the cause of another effect. While it is causing that other effect, it
does not cause hotness. That other effect which heat causes in the
instance of steam, is keeping water in the form of steam. The heat that
there is in steam, over and above two hundred and twelve degrees, is
employed in this way. It is wholly occupied in preserving the water in
an expanded state, and can't cause the mercury in the thermometer to
expand and rise as well. For the same reason, it could give you no
feeling of hotness above what boiling water would--if you had the nerve
to test it. While it is making steam continue to be steam, it is latent.
When the steam becomes water again, it has no longer that work to do,
and is set free. Free heat is what is commonly understood by heat. This
is the heat which cooks our victuals, the heat we feel, the heat that
singes Mr. Merriman. Latent heat is heat that doesn't warm, singe, or
cook, because it is otherwise engaged. If you press gas suddenly into a
fluid, the latent heat of the gas is set free. You seem to squeeze it
out. Indeed, the same thing happens, if you violently force any
substance into a closer form all at once. Every thing appears to have
more or less latent heat in it, between its little particles, keeping
them at certain distances from each other. Compress the particles within
a smaller compass, and a part of the latent heat escapes, as if it were
no longer wanted. When a substance in a compressed state expands on a
sudden, it draws in heat, on the other hand. When a lady bathes her
forehead with eau-de-Cologne to cure a headache, the heat of the head
enters the eau-de-Cologne, and becomes latent in it while it evaporates.
If you make steam under high pressure, you can heat it much above two
hundred and twelve degrees. Suppose you let off steam, so compressed and
heated, by a wide hole, from the boiler, and put your hand into it as it
rushes out--"

"What? Why, you'd scald your hand off!" cried Mr. Bagges.

"No, you wouldn't. The steam rushes out tremendously hot, but it expands
instantly so very much, that the heat in it directly becomes latent in a
great measure; which cools it down sufficiently to a