Steve stood thoughtful for a moment, while second by second the flames were eating farther and farther into the drift, drawing nearer and nearer to the deadly stuff that was piled in cases behind the wooden part.i.tion that stood in the drift beyond the flames just around the bend.

"I'm going through," announced Steve firmly.

"You are not going to try to get through that burning drift, are you?"

"That's exactly what I am going to do. It's our only hope, old man.

We're surely doomed if I don't. If I fail then I shall have done my best. Take off your shirt."

"What for?"

"Because I want to use it."

"Why don't you take off your own?"

"That is exactly what I am going to do," answered the lad, proceeding to strip off the garment. "Be quick! We've no time to lose."

Bob began reluctantly to remove his own shirt, which he tossed to Steve.

"Now, what are you going to do?"

Rush did not answer. He began wrapping the two shirts about his head, having first made slits in one of them through which he could see. Both garments were finally twisted about his head until the latter looked several times its natural size.

"Now I want you to stick right here. If I am overcome you'll have to try your best to get me out."

"Yes; I'll be in nice shape to go after you. I'll singe the skin all off my body if I try it. You get out the best way you can, but, mind you, if that fire creeps much closer to the magazine you'll see me making a lively sprint for a safe place."

"There will be no safe place in the mine if that happens, Bob. I guess you won't run."

"No, I guess I won't, at that," admitted the lad. "What are you going to do when you get in there?"

"I am going to try to block the pa.s.sage so the fire can't get to the magazine. I can't do any less than fail. I will shout if I get safely through the fire; then you will know that I am all right. Good-bye, Bob, if I do not see you again. In case anything happens to me, try to get the men as far away as possible before the blow-up occurs."

Steve Rush bravely bolted into the tunnel of fire. There was fire above his head, sparks falling in a perfect cataract about him, while the drift was full of suffocating smoke.

Bob stood with head bent forward in a listening att.i.tude, apparently unmindful of the shower of burning cinders that fell over him. His whole attention was centred on listening for the call that would signal Steve Rush's safe arrival on the other side of the fire.

It came at last.

"Who-o-o-o-o-p!"

"He's made it!" breathed Bob, with a deep sigh of relief. "I wonder what he is going to try to do? I ought to be in there with him, instead of standing out here doing nothing."

In the meantime Steve, having penetrated beyond the fire zone, made his way quickly to the wooden part.i.tion behind which lay the boxes of high explosives. He gave the door a sharp push, but it did not yield.

"It is locked!" groaned the boy. "I've got to get in there, I've got to do it or we are all lost!"

The fire was by this time less than fifty feet behind him, creeping along toward the powder room at a rapid rate.

Steve backed off and threw himself against the door with all his strength. But the door did not move.

Once more did the lad try to break the door in, the rough wood tearing the skin from his shoulders, sending the blood trickling down his sides in tiny rivulets.

Bang!

He hurled himself against the door for the sixth time. The door gave way with surprising suddenness. Steve Rush plunged headlong into the magazine and went down, entangled in the wreck of the splintered door.

Following his sudden entry into the powder room there came a succession of crashes. At first he thought the dynamite was exploding and the boy clenched his hands to meet the great shock that he felt sure would come shortly.

It did not come. Steve suddenly realized that the dynamite was not going to explode just yet; what he had heard was the falling of some of the dynamite cases to the floor, following the shock of the bursting in of the door.

"What a fool I am," cried the lad, starting to get to his feet.

It was then that he made the discovery that he had taken part of the part.i.tion down with him and that he was so entangled in the wreck that he would have difficulty in extricating himself. Every second the fire was drawing nearer the magazine. Steve fought as he never had fought before. Seconds seemed hours to him, and the crackling of the flames seemed to be about his very ears. The more he struggled the tighter he seemed to be wedging himself under the timbers and planking that he had carried down with him.

With a mighty effort and in sheer desperation the lad lifted the weight with his body. Then by a quick wriggle he managed to squirm from beneath the planking, clearing all but his feet. These were again caught. They would surely have been crushed had it not been for his heavy shoes.

But now the boy's hands were free, thus enabling him to use them in liberating himself. After a struggle of a few moments he succeeded in getting from under the part.i.tion and sprang to his feet.

The electric lights were glowing in the magazine, the circuit not yet having been broken.

At a bound the Iron Boy leaped to the far side of the magazine. From a box on a shelf he selected half a dozen white, paper-covered objects, somewhat resembling wrapped candles, except that they were larger.

This done, Steve whipped out his knife and cut the electric feed wire that led into the magazine. In doing so he got a shock that nearly knocked him down.

"Gracious, but that wire is hot!" he exclaimed, shaking his hand to restore the circulation. "It never seemed so hot as that before.

Everything is hot down here to-day, and I shall be in the same condition if I do not make lively tracks out of here."

Running from the wrecked powder room, the lad sprang down the drift, running straight toward the fire again. As yet he had not replaced the shirts about his head, for he was not yet ready to plunge into the fiery tunnel. The main purpose of his going to the powder room had not yet been carried out.

Reaching a point some twenty feet from the edge of the fire, the lad thrust one of the sticks into a crevice in the rocks. One after another he distributed the sticks in various places, some of them being wedged behind the lagging that supported the drift.

After a few seconds he had distributed them all, forming a line that the fire would be sure to touch before it could get by to reach the magazine.

Steve could hear Jarvis calling to him now. Perhaps Bob had been doing so right along, but if so, Rush had been so occupied with his task that he had not heard.

"Wh-o-o-p-e-e!" answered the plucky lad. "I'm coming. Look out for me."

Taking a final survey of his work, Steve turned toward the fire again.

"Getting out of here is going to be more difficult than getting in," he decided. "I shall be well singed by the time I get through that wall of fire."

Wrapping the shirts about his head, Steve dived into the fiery tunnel, holding his breath as he ran.

The heat was terrific. He could feel it burning through his trousers, and he could smell the burning cloth about his head. He had thrust his hands into his trousers' pockets, which afforded some protection.

Suddenly he stumbled over a timber that had fallen from its supports and measured his length on the ground. As he fell he uttered a shout.

The fall stunned him, for the boy struck on his head. Bob, however, had heard the cry. Regardless of the fact that neither his head nor his body was protected, Jarvis dashed boldly into the burning drift. He knew the skin was peeling from his arms, but he did not experience any sensation of pain.