Q. Why does beating iron make it red-hot?
A. Beating the iron condenses the particles of the metal; and squeezes out its latent heat, as water from a sponge.
Q. Does cold iron contain heat?
A. Yes; every thing contains heat; but when a thing feels cold, its heat is latent.
Q. What is meant by latent heat?
A. Heat not perceptible to our feeling. When anything contains heat without feeling the hotter for it, that heat is called “latent.” (See p. [31].)
Q. Does cold iron contain latent heat?
A. Yes; and when a blacksmith compresses the particles of the iron by his hammer, he squeezes out this latent heat, and makes the iron red-hot.
Q. How did blacksmiths use to light their matches before the general use of lucifers?