We turned and went forward again, passing an open doorway and a few steps which led upwards to the conning-tower. The gangway ran at each side of it.
The long, tunnel-like vista grew narrower and the roof began to slope downward to a point. In front of us, in the extreme bows of the boat, were two huge, circular steel doors, like the doors of a safe, clamped and locked by an intricate mechanism.
"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."