edge of a steep cliff, when there came a sharp report.
"Bless my soul! That's a fuse, I'm sure of it!" cried Mr. Damon.
"No," announced Tom, as he quickly shut off the power. "It's a puncture. One of the inner tubes of the tire has been pierced. I was afraid of that tube."
"What have you got to do; put on a new tire?" asked Mr. Damon.
"No, I'm going to put on a new wheel. I carry two spare ones with tires all ready inflated. It won't take long."
But the process of changing wheels consumed more time than Tom anticipated for the nut was stuck, and he and Mr. Damon had to exert all their strength before they could loosen it. When the new wheel was in place ten minutes had been lost.
"Hold on now, I'm going to speed her!" cried Tom, when they were once more in their seats, and speed the machine he did. The road was rough, but despite this the lad turned on almost full power. Over the bumps they went, around curves and into rain-washed ruts careening from side to side, and throwing Mr. Damon about, as he expressed it afterward, "like a bean inside of a football." As for the young in-
