Despite their disturbed feelings, they all did justice to the meal, and actually felt a little better after it.
While they ate, the rushing of the water against the submarine's sides told them that they were still being towed, and at a good rate of speed, too. But of their destination they were, of course, as much in the dark as ever.
It must have been about ten o'clock that night that the motion ceased, and, peering out through the lenses, they could see lights flashing about on the deck of the tug. Evidently they were coming to an anchorage.
Looking in the other direction, they could now espy the dark, jagged outlines of some sort of land, although, of where they were, they had, of course, not the slightest idea. Old Sam inclined to the opinion—which turned out to be correct—that they had passed through the Straits of Mackinac and were in Lake Michigan.
Suddenly, from the shore, a bright blue light flashed out through the darkness. It appeared and vanished three times. The signal was answered from the tug. Soon afterward, although the prisoners on the submarine did not, naturally, know this, a boat was lowered from the side of the tug, and Captain Rangler, with a few of his worthies, was rowed ashore.
"What are you thinking of, Tom?" asked the professor late that same night.
The captives of the diving-boat had not retired to rest, but were sitting up in the lighted cabin, anxiously awaiting some sign as to what their fate was to be.
Tom had been silent for some time. He sat motionless, except when he made a few sketches with a stub of pencil on the back of an old envelope. It was clear to one who knew him that the boy was revolving some plan.
"I've been thinking that if only we had Mr. Ironsides on board to navigate the submarine, we might escape," said Tom.
"That's so," agreed Jeff; "if those rapscallions took after us, we could dive under and easily elude them."