Klink continued on until he neared the pump station, when he slackened his pace. Fortunately for Steve, there were no lights in that part of the level, so that he had little difficulty in keeping out of sight. Klink kept on walking until nearly opposite the pump station, when he suddenly disappeared. For a moment Rush was puzzled; then he discovered that his man had stepped in between two posts that held up the lagging at the side of the tunnel.
The boy's eyes gleamed.
"Now, my fine gentleman, we'll find out what is going on here! I believe I have landed the man I am looking for. I——"
It was just midnight, and the pump man had left his machinery to go for water to drink with his lunch. Steve understood this, and evidently the man who was pressed close up against the lagging did also, for he quickly stepped out, glanced about him, then ran to the square opening cut in the rocks in which the pump machinery was located.
Rush ran up on tiptoe to within about twenty yards of the pump station. He was watching Klink narrowly. The latter snatched something from inside his coat, thrusting the object under the plunger of the largest of the pumps. Next came something long, slender and white that looked like a large string.
Almost holding his breath, Steve crept nearer.
"He is attaching a fuse. That was dynamite that he put under the plunger. He's going to blow up the pumps and flood the mine!"
Klink struck a match and applied it to the end of the fuse.
It was now Steve Rush's time to act. Seconds were precious. The boy seemed scarcely to touch the ground as he sprinted forward. He was upon the man before Klink saw him. One swift kick from Steve's heavy boot toppled the man over on his side.
The Iron Boy snatched the burning fuse from the stick of dynamite and hurled it from him.