Saying which Nicolas saluted, and, as became his position of servant, fell
back some yards. But first he had dropped the blankets to the beach.

The light of lanterns showed that the men of one gang were searching
thoroughly all along the top of the wall. Once in a while a man belonging
to the beach patrol passed the chief engineer and the superintendent,
reporting only that no signs of Harry had been found.

An hour thus passed. Then, from over the water, as the lantern-bearing
searchers were returning, a dull explosion boomed across the water.

"Great Scott!" quivered Tom. "There they go at it again, Mr. Renshaw!
Another section of the retaining wall has gone---blown up!"




CHAPTER V

WANTED---DAYLIGHT AND DIVERS


In a trice the foreman of the gang on the wall wheeled his men about,
running them out seaward toward the scene of the latest explosion. That
much was plain from the twinkling of the rapidly-moving lanterns.

"Come on, Renshaw!" Tom shouted. "You, too, Nicolas. You can pull an
oar."