"But how about the land party?" asked Jack.
"The German base," said Captain Jack, "extends along the southern extremity of the island for perhaps a mile. You see, therefore, that it's small. I don't believe there are more than a dozen submarines there. Whether there are more large raiders, I can't say. I wouldn't be surprised, however, if the one you put a torpedo into the other night was the last. That would mean that ashore, besides whatever number of the submarine crews that are aboard their vessels, there would be comparatively few men. We'll count the submarine crews as twenty-five men to a ship. That's 300 men. There may be an additional hundred men on the ground, but I doubt it."
"But they must have some means of protection," said Jack. "Big guns, and rifles a-plenty."
"Rifles, yes," was the reply, "but few big guns. They feel so secure in their hiding places that they have made use of their guns mostly to arm merchant raiders."
"I see," said Jack. "Well, we'll have to leave something to chance. Now the question arises as how best to destroy the place, submarines and all."
"Well, I can fix that, too," said Captain Jack. "Bombs are the things to do the trick. Half a dozen bombs scattered about and timed nicely, and there won't be a German submarine base at this time tomorrow."
"All right so far as the land side goes," said Frank, "but how about the submarines?"
"Mines," said Captain Jack quietly, "timed to explode simultaneously with the bombs ashore. You can lay them from the submarine."
"By Jove!" said Jack. "You'd make a first class combined general-admiral, Captain Jack," declared Captain Glenn.
Captain Jack smiled slowly.