As the molten mass cooled and solidified he took it out of the
water and laid it on an anvil.

Then his assistant began to hammer it with careful, sharp blows,
chipping off the outside.

"You see, we have to get down to the core of carbon gently," he
said, as he picked up the little pieces of iron and threw them
into a scrap-box. "First rather brittle cast iron, then hard
iron, then iron and carbon, then some black diamonds, and in the
very centre the diamonds.

"Ah! we are getting to them. Here is a small diamond. See, Mr.
Spencer--gently Francois--we shall come to the large ones
presently."

"One moment, Professor Poissan," interrupted Craig; "let your
assistant break them out while I stand over him."

"Impossible. You would not know when you saw them. They are just
rough stones."

"Oh, yes, I would."

"No, stay where you are. Unless I attend to it the diamonds might
be ruined."

There was something peculiar about his insistence, but after he
picked out the next diamond I was hardly prepared for Kennedy's
next remark.