"Just blown out the water tanks, old soul. Feel her lift? Now her whale-back is above water and we'll go and say good-morning to the sun, which I perceive is very kindly beginning to show himself. But before that ..."

He shouted another order and there came a deafening din from below. Bang! Bang! Bang! till the whole steel hull quivered.

"That is the surface engine starting. It'll be all right in a minute," and even as he spoke, the noise subsided into a regular throb. It was for all the world like a motor car starting on bottom speed and then slipping into top gear.

Scarlett came hurrying up into the conning-tower and he and my brother unlocked the sliding hatch. In a minute we had emerged into the keen air of the morning. How fresh and sweet it seemed to me it is impossible to say. The sun was rising. The bitter cold of the marshes had gone. The small waves were flecked with gold as we stood upon the wet steel plates and drank in the air as if it had been wine.

"An ideal day for a submarine action!" Bernard said, rubbing his hands. "There's just enough ripple on the surface to make us difficult to detect, and yet it is smooth enough to give me a clear view. This boat is beautifully trimmed, she doesn't roll a bit. I'll send those boys up in a minute or two, but meanwhile I've got to play a bit of bluff. A lot depends on it."

I nodded. It was not my place to ask questions.

"You see," he went on, "of course the German battleship expects us. I know exactly the spot in the North Sea where we are supposed to pick her up some time after lunch—provided, of course, that the Germans have carried out their plans successfully and our scouts really have been decoyed away. It is part of a huge scheme.

"Well, assuming that their own plans are successful, they will be on the look-out for us and they'll send us a wireless message when we're within close range. This will be some prearranged signal, a single letter repeated a certain number of times or something of that sort, so that any of our ships picking it up would not know what it meant. We've got a wireless mast on board which can be shoved up at will and there's a complete installation in a little room down below next to the cook's galley. Unfortunately there is not one of us who knows anything about wireless. Bosustow is a capable electrician and could control the machinery, but he can't understand the signals. Therefore, when we sight the Friesland—and I want to get as near her as possible so as to make no mistakes—we must signal with flags.

"I've got their signal book and in it is a special code made for this occasion. The flags are in the flag locker all right, but I don't understand a word of German and none of us here do, so I'm going to put the fear of God into our friend, Karl of the Portsmouth Royal. A lot depends on that.

"Just skip down, young John, and tell Scarlett to bring him up here."