A withering blast of hot air reached the young engineers as the
oven door of the portable assay furnace was thrown open. The
crucibles were raked out and set in the air to cool.

"Would fanning the crucibles with my hat do any good?" asked Hazelton
eagerly.

"Some," yawned Tom, "if you're impatient."

Reade strolled off under the trees, whistling softly to himself.
Jim Ferrers smoked a little faster, the only sign he gave of
the anxiety that was consuming him. Harry frequently sprang to
his feet, walked up and down rapidly, then sat down again. Two
or three times Hazelton burned his fingers, testing to see whether
the crucibles were cool enough to handle. At last Tom strolled
back, his gaze on the dial of his watch.

"Cool enough for a look, now, I think," Reade announced.

Harry bounded eagerly toward the crucibles, feeling them with
his hands.

"Plenty cool enough," he reported. "But how did you guess, Tom?"

"I didn't guess," Reade laughed. "I've timed the crucibles before
this, and I know to a minute how long it ought to take."

"What a chump I am!" growled Harry, in contempt for self. "I
never think of such things as that."