Looking back, the lads saw two destroyers racing in the wake of the submarine, preceded by a small gunboat.
The first shells of the gunboat whizzed by the submarine.
Captain Nicholson slammed down the hatch.
"Water armor for us!" he cried.
A moment later the submarine was on the safe haven of the bottom with 100 feet of solid protecting water between it and hostile shells.
"That was pretty ticklish," said Frank, drawing a breath when they were out of reach of the gunboat's fire.
"It was," was the commander's response, "and we are not safe yet by any means."
"Why—?" began Frank.
"We can't go up again now, can we?" demanded Captain Nicholson. "We shall have to stay down here until they believe we have escaped. Then we will rise and try to sneak out."
"But surely we are safe enough down here."
"Don't you believe it. They'll trawl for us all day; but luckily for us they don't know we have lost our batteries, so they'll probably search over a wide area, and we run that much more chance of not being discovered."