"What strength has charcoal?"
"Scarcely any."
"Crystallize it, and the diamond results."
"I did not speak of diamond."
"Ah! and is not the same amount of the same material present in each, a grain of diamond and a grain of charcoal? What is present in a grain of diamond that is not present in a grain of charcoal?"
"Go on."
"Answer my question."
"I can not."
"Why does brittle, cold zinc, when heated, become first ductile, and then, at an increased temperature, become brittle again? In each case the same material is present."
"I do not know; but this I do know: I am an organized being, and I have strength of body."