Page:Tom Swift Among the Diamond Makers.djvu/191



the adventurers looked through the opening at the end of the passage into the larger cave. The men opened the small oven in which the balls of white chemicals and carbon mixed, had been baked, and a pile of things, that looked like irregularly-shaped marbles, were placed in the steel box.

This box, which was about the size of a trunk, was of massive metal. It was placed in a recess in the solid rock, and all about were layers of asbestos and other substances that were nonconductors of heat.

"That box becomes red hot," exclaimed Mr. Jenks, in a whisper. "When things are in readiness, that lever is pulled and the diamonds are made. I pulled it once, but I did not then know the process involved. I supposed that the lightning had nothing to do with making the diamonds."

"It has—a most important part," said Mr.