Forward is another narrow steel vault serving at once as engine-room and crew's quarters. Next to it is a place like a cupboard, where the cook has just room to stand in front of his doll's house galley-stove. It is electrically heated, that the already oppressive air may not be further vitiated by smoke or fumes. A German submarine in any case smells perpetually of coffee and cabbage. Two little cabins of the size of a decent clothes-chest take the deck and engine-room officers, four of them. Another box cabin is reserved for the commander—when he has time to occupy it.
At daybreak the commander comes on deck in coat and trousers of black leather lined with wool, a protection against oil, cold, and sea-water. The crew at their stations await the command to cast off.
"Machines clear," calls a voice from the control-station and "Clear ship," snaps the order from the bridge. Then "Cast-off!" The cables slap on to the landing-stage, the engines begin to purr, and U-47 slides away into open water.
A few cable-lengths away another submarine appears homeward bound. She is the U-20 returning from a long cruise in which she succeeded in sinking a ship bound with a cargo of frozen mutton for England.
"Good luck, old sheep-butcher," sings the commander of U-47 as the sister-ship passes within hail.
The seas are heavier now, and U-47 rolls unpleasantly as she makes the light-ship and answers the last salute from a friendly hand. The two officers on the bridge turn once to look at the light-ship already astern, then their eyes look seaward. It is rough, stormy weather. If the egg-shell goes ahead two or three days without a stop, the officers in charge will get no sleep for just that long. If it gets any rougher they will be tied to the bridge-rails to avoid being swept overboard. If they are hungry, plates of soup will be brought to them on the bridge, and the North Sea will attend to its salting for them.
Frequently this "meal" is interrupted by some announcement from the watch, such as: "Smoke on the horizon off the port bow." Then—so we are told:
The commander drops his plate, shouts a short, crisp command, and an electric alarm whirs inside the egg-shell. The ship buzzes like a hive. Then water begins to gurgle into the ballast-tanks, and U-47 sinks until only her periscope shows.
"The steamship is a Dutchman, sir," calls the watch officer. The commander inspects her with the aid of a periscope. She has no wireless and is bound for the Continent. So he can come up and is glad, because moving under the water consumes electricity, and the usefulness of a submarine is measured by her electric power.
After fifty-four hours of waking nerve tension, sleep becomes a necessity. So the ballast-tanks are filled and the nutshell sinks to the sandy bottom. This is the time for sleep aboard a submarine, because a sleeping man consumes less of the precious oxygen than one awake and busy. So a submarine man has three principal lessons to learn—to keep every faculty at tension when he is awake, to keep stern silence when he is ashore (there is a warning against talkativeness in all the German railway-carriages now), and to sleep instantly when he gets a legitimate opportunity. His sleep and the economy of oxygen may save the ship. However, the commander allows half an hour's grace for music. There is a gramophone, of course, and the "ship's band" performs on all manner of instruments. At worst, a comb with a bit of tissue paper is pressed into service.