This does not take long. As soon as a tank is empty the excess air rushes out with a pleasant sound at the side of the boat, and we are soon in normal floating trim again.
We are still using electricity. Now comes last of all the starting up of the heavy Diesel engines by the electric motors.
I have already climbed into the conning-tower and can see nothing of all this, except by the communications from the control-room. Those who are in the engine-room, however, will have an exciting spectacle.
The observation engineers stand at their posts. A command comes through the speaking-tube. Everything is ready. Then the chief engineer gives a shrill whistle, raises his hand, two quick wrenches at the switchboard in the electrical engine-room, a couple of blinding flashes half an inch long: the first valve-heads rise slowly, hesitatingly, as if unwilling, then quicker, a wild report and hissing, a wild irregular spluttering, then the loud explosions become rhythmical, and faster and faster both machines resume their regular vibrations.
The submerging test is completed, and pounding along the "Deutschland" proceeds on her way. The wind does not drop, but the weather keeps fine and the visibility is good.
No steamer comes in sight: we can remain comfortably above water. Nevertheless we need to be extremely careful in our navigation.
So the day draws to its end. But as the sun sinks, dark threatening clouds appear, prophesying bad weather for the following day.
CHAPTER IV
THE U-BOAT TRAP
And thus it turns out. The further we get from land, the rougher grows the sea. The boat is badly tossed about. I notice the roughness of the sea as I lie in my cabin, and towards two o'clock in the morning I am awakened by a "Hullo," from the speaking-tube on the wall at my head.
The watchful second officer, Eyring, announces a white light to starboard which is approaching rapidly.