But what Bart wished he never told, for, at that instant there came from the street outside a series of sharp explosions, that sounded like a Gatling gun in full operation.

“What’s that?” cried Fenn.

“It’s an automobile!” replied Frank, who was nearest the window. “It’s running away, too, from the looks of it. They’ve opened the muffler and are trying to reverse I guess! Something’s wrong! There’s going to be an accident!”

The other boys crowded up back of Frank to see what was going on. The street in front of Fenn’s house sloped sharply down to a cliff at the end of the thoroughfare. Across the highway was a stout fence, designed to prevent any one from driving over the cliff, which was quite high. Toward this fence a big touring car, which, as the boys could see, contained an elderly gentleman and a young lady, was rushing at furious speed.

“Stop! Stop!” cried Fenn in desperation, thinking the man in the car did not know or realize his danger. “The street ends at the fence! You’ll go over the cliff!”

As the auto whizzed past the house the girl in it gave one glance at Fenn. The youth thought her the most beautiful person he had ever seen, though there was a look of terror in her eyes.

“He can’t stop!” shouted Bart. “Something’s wrong with the machine!”

Indeed this seemed to be true, for the man at the steering wheel was frantically pulling on various levers and stamping, with his feet, on some pedals in front of him.

The young woman in the car half arose in her seat. The man, holding the wheel with one hand, held her back with the other. She gave a startled cry and, a moment later the auto had crashed through the fence, as though it was made of paper, and the front wheels disappeared over the edge of the cliff.

“Come on!” cried Bart. “We must go to their help!”