"These are the mouths of the torpedo expulsion tubes," said Bernard. "We carry six torpedoes, I am glad to find—two more than I should have expected in a boat of this size—and, by Jove, we shall want 'em! If we throw away a single one, the game will be up, I expect. The torpedoes are run into these tubes along steel rails. They're discharged from the tubes by compressed air from the air tanks below. I see here the pressure is several thousand pounds to the square inch. In some boats we send out the tin fish by exploding a few ounces of cordite, but the air is the better way."
He turned to where Scarlett was busy and I saw a submarine torpedo for the first time. I confess there was a little inward shudder as I looked upon the deadly thing that could send the largest battleship afloat to the bottom in a few minutes. It was like a huge fish of steel with a large propeller at one end.
"These are beauties," Bernard said, "and to think that we are going to have the chance of using them against their original owners!" He chuckled.
"The propelling engines," he went on, "are inside—for you must remember that a torpedo is a little ship in itself and is not a projectile at all. There are three hundred pounds of trinitrotoluene in this beauty—we've done away with the old-fashioned gun-cotton now—and she's got a range of seven thousand yards—over four miles, Johnny, my boy! Now, Mr. Dickson and Mr. Harold Dickson, you will stay here with Scarlett. It will be your part, when we go into action, to fire these torpedoes. There ought to be six or seven of you to do it. There are only three, and two of you are quite untrained. Scarlett, get to work at once and give these gentlemen a practical drill. Show them exactly what they will have to do and explain the orders that will come from me. Miss out anything superfluous; remember we've hardly any time. Just teach them what is absolutely necessary."
"Aye, aye, sir!" said Scarlett, and as we turned back I heard him at once beginning his lecture.
And now we came to the most interesting part of that world of marvels, to the brain of the submarine. Adams stood in the first stage of the conning-tower, his hands upon a little leather-covered steering-wheel. In front of him was a gyroscopic compass and a row of speaking-tubes. A light threw a bright radiance upon a framed chart hanging on the wall, marked everywhere with faint purple pencil lines.
Bernard glanced at the compass and gave the man a few directions. Then we went up a short ladder of half a dozen rungs into the highest chamber of all.
It was perfectly circular. There was just room for two or three people, and the steel roof was two feet above our heads. A great tube came down through the roof and disappeared beneath the open grating of the floor. It was like the mast of a ship going through the cabin down to the very gar-board strike. There was a row of brass clock-faces with trembling needles and oddly shaped gauges, in which coloured liquid rose and fell. The whole ganglion of nerves met here in the cerebellum of the ship, and at a glance its commander knew exactly what she was doing, her speed, her depth below the surface of the water, the pressure—a thousand other things which I am not competent to name. The whimsical idea came to me that it was like lifting up the top of a man's head and seeing the thoughts which controlled every motion of his body.
There were charts, also, spread upon a semi-circular shelf of mahogany, with dividers, compasses, and a large magnifying glass.
Fastened to the wall, just above this shelf, was something that touched me strangely. It was a photograph in a silver frame, the photograph of a young, light-haired girl, and upon it was written in German, "An meinem lieber Otto."