Jack was looking up the river as he spoke, and at a distance saw a series of rocks jutting out for a considerable distance into the stream. "I am going out on those rocks and then trust to luck to get over to the other side," he said. "We can't get at that fallen tree from this side." "All right, I'm with you, Jack," said Randy. And together they made their way out on the rocks mentioned and the others slowly and cautiously followed. I know it will not be necessary to introduce the Rover boys to my old readers. But for the benefit of those who are now meeting them for the first time a few words of introduction will not come amiss. In my first volume, entitled "The Rover Boys at School," I related how three brothers, Dick, Tom and Sam Rover, were sent to Putnam Hall Military Academy, where they made a great number of friends, including a cadet named Lawrence Colby. After passing through Putnam Hall, the boys attended Brill College, and then joined their father in business in New York City, with offices on Wall Street. They organized The Rover Company, of which Dick was now president, Tom secretary and general manager, and Sam treasurer. The three youths were married and lived in three connecting houses on Riverside Drive, overlooking the Hudson River. About a year after their marriage Dick and his wife became the parents of a son, who was named John, after Mrs. Rover's uncle, Mr. John Laning. This son was followed by a daughter, named Martha, after her great-aunt Martha of Valley Brook Farm. The boy Jack, as he was commonly called, was a sturdy youth with many of the qualities which had made his father so successful. It was around this time that Tom Rover and his wife Nellie came to the front with a great surprise. This was in the nature of a pair of lively twins, one of whom was named Anderson, after his grandfather, and the other Randolph, after his great-uncle Randolph of Valley Brook Farm. Andy and Randy, as they were always called, were exceedingly active lads, in that particular being a second edition of their father, Tom. About the time Tom's twins were born Sam Rover and his wife Grace became the parents of a little girl, whom they called Mary, after Mrs. Laning. Then, a year later, the girl was followed by a boy, who was christened Fred after Sam Rover's old school chum, Fred Garrison. Residing so close together, the younger generation of Rover boys, as well as the sisters, were brought up very much as one family. When they were old enough all were at first sent to private schools in the Metropolis. But soon the boys, led by Andy and Randy, showed such a propensity for "cutting loose" that their parents were compelled to hold a consultation. "We'll have to send them to some strict boarding school--some military academy," said Dick Rover.