Then Herb, who was the stronger of the two, ran up the rungs until he was directly opposite his comrade.

“I’ll hold on to one arm, Joe,” cried Bob. “Let go the pipe with the other and give it to Herb.”

Joe did as directed and the two boys swung him over to the ladder. He felt for the rung with his feet, and when they were firmly planted on it, Herb placed one of his hands on another rung and Bob followed suit. Then while Jimmy held the ladder at the foot to keep it from slipping, Joe and Herb made their way slowly to the ground and Bob came after.

They seated Joe on a box that stood nearby, and his comrades crowded around him; joyful beyond words at his narrow escape, clasping his hands and slapping him on the back.

Joe was gasping under the muscular and nervous strain that he had undergone in the few minutes that had seemed to him like ages, but he rallied gamely and tried to joke.

“I said I was going to get down off that roof quick,” he said. “But I came mighty near coming down quicker than I wanted to. I can’t thank you fellows enough.”

And while they stand around him jubilating over his rescue, it may be well, for the benefit of those who have not read the preceding volume of this series, to tell who the Radio Boys were and what had been their adventures up to the time this story opens.

Bob Layton was a stalwart, vigorous youth of fifteen years, who lived in the thriving town of Clintonia, a city of about ten thousand population and located some seventy-five miles from New York City. His father was a prosperous druggist and chemist, esteemed and respected, and a leader in the civic life of the town. Bob was tall for his years, of dark complexion, with merry, flashing eyes. He was a leader in baseball, football, and the other athletic sports in which boys of his age delight. He was frank, truthful, courageous and a general favorite.

His special chum was Joe Atwood, son of a prominent doctor of Clintonia. Joe differed from Bob in being fair-skinned instead of dark. But the qualities of character of both boys were such as to make them close friends, and where one was to be found the other was seldom very far away. Joe, however, was impulsive, and his temper was of the “hair trigger” variety that required frequent curbing from his cooler-headed chum.

Of the many friends they had in town, the chief perhaps were Herbert Fennington and Jimmy Plummer. Herbert, or Herb, as he was usually called, was the son of a merchant, and was an easy-going, good-natured boy who was not especially fond of work, but who had an unusual liking for jokes and conundrums. He was slightly younger than Bob and Joe, but not enough to make much difference. Jimmy Plummer, the youngest of the four, was the son of a carpenter. He was jolly, fat, and round, with an appetite that made him the subject of good-natured jesting on the part of the other boys. He had been nicknamed “Doughnuts” because of his special fondness for that toothsome delicacy, and he did his best to live up to the name.