“Need you?” sneered the other.  “What for?”

“Well, for one thing, there are other tests ahead of the submarine boats.”

“Can you win any of those tests?” jeered Rhinds, harshly.

“No; but I can do what will, perhaps, be the next best thing.  I can stop the boys aboard the Pollard craft from being on hand to put their boat through all its paces.  All you need is to have the Pollard end blocked.  You can more than hold your end against the other submarines.”

“Well, what can you do to stop the boys on the Pollard boats?” demanded Rhinds, unbelievingly.

“I can stop them from being on hand at the next tests.  Or else I can attend to them so that they’ll be of very little use, anyway.”

“Bah!  You’re dreaming, Fred!  The boys were too smart for you last time; Now that they’re on their guard, don’t you realize they’d be harder than ever to catch.”

“Jack Benson and his friends don’t know that I was behind what happened last night,” retorted Radwin.  “Besides, if they’re on their guard, now, so am I. I know them to be smarter than I first thought, so I shall spread a deeper, tighter net for them.  John Rhinds, you shall win the rest of the submarine tests.  At least, the Pollard boats won’t win!”

Radwin talked so confidently that John Rhinds began to look at him more hopefully.

“What are you going to do, Fred?” the wretch inquired, at last.

“I’m going on shore—­now.”

“Everybody will know, if you call a boat at this hour of the night.”

“Bosh!  You and I are both going on shore—­back to the Somerset House.  Anything very strange about that?” demanded Radwin.  “We’re tired out from the day’s cruise, and want to be off the water.  So we’re going to the Somerset.  We’ll drift in, get something to eat, and then start upstairs.  You can hardly go to sleep, Rhinds, but I shall start out again, on the sly, and go to find some handy people I know in the little city of Colfax.  So that’s settled, and I’ll signal for the boat now.”

Jack and his comrades slept on the “Benson” that night.  For one thing, they felt so tired, after the day’s long strain, that they really lacked the desire even to go to larger, softer beds on shore.  So they awoke in the morning feeling as fresh as sea-larks should.

“There are no tests on for to-day, and nothing to be done on board, except to clean the engines,” spoke Jacob Farnum over the breakfast table in the little cabin.  “So, youngsters, we’ll go ashore and refresh ourselves.  Grant’s men will clean the engines.  That’s what they’re really here for.”

“Don’t you think it would be wiser, sir, to remain on board?” smiled Captain Jack.  “As you will remember, we found the shore rather too lively the last time we were there.”

“Things happened because you boys got out of our sight,” chuckled the shipbuilder, quietly.  “That’s the point.  What you youngsters need is a brace of guardians.  So, while you’re to go on shore, Dave and I will go along, and you’re not to get out of our sight.  Remember that.”