Two days later they picked up their convoy and all felt a very comforting sense of security in the presence of the destroyers with their business-like air and wicked looking guns.
They kept pace with the liner, within easy reaching distance, occasionally exchanging signals, and keeping sleepless watch day and night over the huge transport.
"The finest navy in the world!" cried Frank, with enthusiasm, as his kindling eyes rested on these "bulldogs of the sea." "That's one branch of the service where Uncle Sam has never fallen down. Man for man, gun for gun, and ship for ship, there's nothing in the world can beat them. Just watch them clean out that U-boat nest when they once get over there in force."
"They'll do to them what Decatur did to the Barbary pirates years ago," said Bart. "Every other nation was paying tribute to them, but that idea didn't make a hit with us and we went in and wiped them off the face of the earth—or rather the face of the water. And what we did once, we can do again."
Frank's eyes had been idly roaming over the sea while they were talking, but suddenly his gaze became fixed and he started to his feet.
"Did you see that, fellows?" he demanded, sharply.
"Where?" asked Billy
"I didn't see anything," said Bart.
"It looked like a flash of light on the water," explained Frank. "There it is again. Great Scott, it's a periscope!"
Almost as he spoke, the forward guns on the liner roared their challenge, followed by the deeper bass of the guns from the nearest destroyer.