"Running lights!" shouted Frank.
The lights flashed. Frank kept an eye forward. Directly he got a return flash from the ship ahead, and then picked up her shape again.
Morning dawned and still the fleet sped on. Toward noon the weather cleared. Officer and men kept their watches by regular turn during the day. At sundown the four destroyers slowed down and circled around in a slow column. The eyes of every officer watched the clock. They were watching for something. Directly it came—a line of other ships, transports filled with wounded soldiers returning to America. These must be safely convoyed to a certain point beyond the submarine zone by the Plymouth and her sister ships.
On came the transports camouflaged like zebras. The Plymouth and the other destroyers fell into line on either side of the transports.
"Full speed ahead," was Captain Templeton's signal to the engine room.
"Take a look below, Frank," said Jack to his first officer.
"Aye, aye, sir."
Frank descended a manhole in the deck. He closed the cover and secured it behind him. At the foot of the ladder was a locked door. As it opened, came a pressure on Frank's ear drums like the air-lock of a caisson. Frank threaded his way amid pumps and feed water heaters and descended still further to the furnace level.
Twenty-five knots—twenty-eight land miles an hour—was the speed of the Plymouth at that moment. It was good going.
Below, instead of dust, heat, the clatter of shovels, grimy, sweating fireman, such as the thought of the furnace room of a ship of war calls to the mind of the landsman, a watertender stood calmly watching the glow of oil jets feeding the furnace fire. Now and then he cast an eye to the gauge glasses. The vibration of the hull and the hum of the blower were the only sounds below.