Calling the midshipman to him, the skipper briefly outlined his plans and made him a similar offer.
"Only too glad of the opportunity, sir," declared Farnworth, his eyes glistening at the prospect of a daring piece of work.
"I'm glad of it," rejoined the Lieutenant-Commander. "Having completed our fit-up, I was not keen on displaying it to the eyes of the fleet. I'd rather wait until it has proved its merits. Well, we are ready to start. We'll submerge to ten feet, and if you'll stand by, Mr. Crosthwaite, and help me to con her into this secret lair, I'll be everlastingly grateful."
"How do you propose to attack—by gunfire or torpedo?" enquired Dick.
"Oh, torpedo, by all means. Let the Germans know that we can use the 'tinfish' whenever we get something worth going for."
The crew were now at their diving-stations.
Calmly and distinctly the Lieutenant-Commander gave his orders, and with a barely perceptible tilt the submarine dived till the gauge registered the required distance.
It was still dark. Through the periscope, only the rugged outlines of the shore were visible. Distance has to be estimated by the apparent height of the land; while steering a compass course the submerged vessel simply groped along, with her extended periscope rising clear of the turtle-back girder and showing less than two feet above the surface.
"We ought not to be far from the spot now," remarked the skipper after an hour had elapsed. "Do you make anything of it?"
Dick, who had borrowed a razor from an obliging officer and had removed his moustache and stubbly beard, was carefully examining the image in the object-bowl of the periscope. It revealed a seemingly unbroken coast, backed by two lofty mountains, one of which was serrated on its western side.