"Catch hold of my shoulders, Ping," he ordered.

Ping's arms went around him in a life-and-death grip. Then, supporting himself with one hand, Matt detached the Chinaman from the hook with the other and both slid to the pier in safety.

"You gave us a scare, Ping," said Matt. "We didn't know but you had found some one sneaking around the boathouse. How did you get in that fix?"

Ping explained, and the boys had a good laugh. Shortly afterward Lorry dragged his motor cycle to the top of the bank and chugged away home.

It was about two o'clock when Newt Higgins, the young machinist, arrived with the new motor. His father had brought him across. The engine was unloaded by means of the block and tackle and carried inside.

While Higgins was taking the old motor out of the Sprite, Matt connected up the new one with gasoline tank and battery and got it to going. It ran perfectly.

From that time on there were several days of feverish activity in the boathouse. The hull of the Sprite had to be strengthened. The original motor had been installed on short bearers, which, according to Matt's view, was entirely wrong. The motor bed, he held, must be rigid and the vibration distributed over as great an area as possible.

A heavy bed was put down, and on this two girders were laid, shaped up to take the rake of the motor and tapering off at the ends. These girders extended as far forward and aft as the curve of the hull would allow.

Lining up the shaft was an operation which Matt attended to himself. This job gave some trouble, but was finally finished to his satisfaction.

The new engine was set farther aft than the old one had been. This enabled Matt to bring the gasoline tanks farther aft, as well. The hood had to be made longer, and a stout bulkhead was built between the engine space and the cockpit.