As soon as the foreman had gone Tom stepped into the motor boat, taking the wheel.
"Tune up the engine, Conlon," Reade directed the engine tender. "I'm going to take a run around to the west side of the wall. I'm going to try to find the tubes of high explosive that I'm satisfied were planted in the wall."
"That's a fine job for a dark night, sir," grumbled Conlon. "Suppose we run into the bombs, and they prove to be contact exploders, too?"
"That's one of the risks of the business," Tom retorted grimly.
Before the motor boat had gone far Tom called one of the men aboard to take the wheel. Then the young chief engineer began to experiment with the searchlight.
"What's the idea, sir?" asked Conlon, looking on.
"I want to depress the light, so that we can use it to look down into the water."
"And try to find the bombs?"
"Exactly," Reade nodded.
"Lucky if we don't find the bombs with the keel of the boat," observed
Conlon.