Everything being in readiness, the fires were lit and the generation of steam gotten under way. At a signal the engine’s mechanism responded to the movement of a lever. Almost immediately there was a crash that shook the ship from stem to stern. It was at once apparent to all on board that something serious had happened. Everyone was at the moment on deck, except those engaged in the engine room, and to that spot all ran to investigate.

Berwick was found with a wounded hand, resulting from his efforts to stop the machinery. Juarez had accomplished this, but to the gaze of all there was offered a badly wrecked mechanism. Berwick was livid with rage and more concerned by the mishap to the engine than by the pain in his injured hand.

Someone, it was found, had tampered with the machinery. Who was the culprit?

“How serious is the injury?” inquired the professor.

Berwick shook his head and looked at his injured member, about which Jim was skilfully applying a bandage.

“I fear it will be several days,” was the gloomy response. “But we will get right at it.”

Even Berwick, however, was disappointed with the progress he could make toward repairing the distorted machinery, although he had the helpful aid of all the boys. There were exasperating delays. Essential parts of the machinery were not to be found and substitutes had to be made.

The unvarying calm and sultry heat persisted.