When President Boon had heard our story he promptly approved Hall’s dismissal of the men. He expressed great surprise that Dr. Syx should have resorted to a deception which had been so disastrous to innocent people, and at first he talked of legal proceedings. But, after thinking the matter over, he concluded that Syx was too powerful to be attacked with success, especially when the only evidence against him was that he had claimed to find artemisium in his mine at a time when, as everybody knew, artemisium actually was found outside the mine. There was no apparent motive for the deception, and no proof of malicious intent. In short, Mr. Boon decided that the best thing for him and his stockholders to do was to keep silent about their losses and await events. And, at Hall’s suggestion, he also determined to say nothing to anybody about the discovery we had made.

“It could do no good,” said Hall, in making the suggestion, “and it might spoil a plan I have in mind.”

“What plan?” asked the president.

“I prefer not to tell just yet,” was the reply.

I observed that, in our interview with Mr. Boon, Hall made no reference to the side tunnel to which he had appeared to attach so much importance, and I concluded that he now regarded it as lacking significance. In this I was mistaken.

A few days afterwards I received an invitation from Hall to accompany him once more into the abandoned tunnel.

“I have found out what that sidetrack means,” he said, “and it has plunged me into another mystery so dark and profound that I cannot see my way through it. I must beg you to say no word to any one concerning the things I am about to show you.”

I gave the required promise, and we entered the tunnel, which nobody had visited since our former adventure. Having extinguished our lamp, my companion opened the peep-hole, and a thin ray of light streamed through from the tunnel on the opposite side of the wall. He applied his eye to the hole.

“Yes,” he said, quickly stepping back and pushing me into his place, “they are still at it. Look, and tell me what you see.”

“I see,” I replied, after placing my eye at the aperture, “a gang of men unloading a car which has just come out of the side tunnel, and putting its contents upon another car standing on the track of the main tunnel.”

“Yes, and what are they handling?”

“Why, ore, of course.”

“And do you see nothing significant in that?”

“To be sure!” I exclaimed. “Why, that ore—”

“Hush! hush!” admonished Hall, putting his hand over my mouth; “don’t talk so loud. Now go on, in a whisper.”

“The ore,” I resumed, “may have come back from the furnace-room, because the side tunnel turns off so as to run parallel with the other.”

“It not only may have come back, it actually has come back,” said Hall.

“How can you be sure?”

“Because I have been over the track, and know that it leads to a secret apartment directly under the furnace in which Dr. Syx pretends to melt the ore!”

For a minute after hearing this avowal I was speechless.

“Are you serious?” I asked at length.

“Perfectly serious. Run your finger along the rock here. Do you perceive a seam? Two days ago, after seeing what you have just witnessed in the Syx tunnel, I carefully cut out a section of the wall, making an aperture large enough to crawl through, and, when I knew the workmen were asleep, I crept in there and examined both tunnels from end to end. But in solving one mystery I have run myself into another infinitely more perplexing.”

“How is that?”

“Why does Dr. Syx take such elaborate pains to deceive his visitors, and also the government officers? It is now plain that he conducts no mining operations whatever. This mine of his is a gigantic blind. Whenever inspectors or scientific curiosity seekers visit his mill his mute workmen assume the air of being very busy, the cars laden with his so-called ‘ore’ rumble out of the tunnel, and their contents are ostentatiously poured into the furnace, or appear to be poured into it, really dropping into a receptacle beneath, to be carried back into the mine again. And then the doctor leads his gulled visitors around to the other side of the furnace and shows them the molten metal coming out in streams. Now what does it all mean? That’s what I’d like to find out. What’s his game? For, mark you, if he doesn’t get artemisium from this pretended ore, he gets it from some other source, and right on this spot, too. There is no doubt about that. The whole world is supplied by Syx’s furnace, and Syx feeds his furnace with something that comes from his ten acres of Grand Teton rock. What is that something? How does he get it, and where does he hide it? These are the things I should like to find out.”

“Well,” I replied, “I fear I can’t help you.”

“But the difference between you and me,” he retorted, “is that you can go to sleep over it, while I shall never get another good night’s rest so long as this black mystery remains unsolved.”

“What will you do?”

“I don’t know exactly what. But I’ve got a dim idea which may take shape after a while.”

Hall was silent for some time; then he suddenly asked:

“Did you ever hear of that queer magic-lantern show with which Dr. Syx entertained Mr. Boon and the members of the financial commission in the early days of the artemisium business?”

“Yes, I’ve heard the story, but I don’t think it was ever made public. The newspapers never got hold of it.”

“No, I believe not. Odd thing, wasn’t it?”

“Why, yes, very odd, but just like the doctor’s eccentric ways, though. He’s always doing something to astonish somebody, without any apparent earthly reason. But what put you in mind of that?”

“Free artemisium put me in mind of it,” replied Hall, quizzically.

“I don’t see the connection.”

“I’m not sure that I do either, but when you are dealing with Dr. Syx nothing is too improbable to be thought of.”

Hall thereupon fell to musing again, while we returned to the entrance of the tunnel. After he had made everything secure, and slipped the key into his pocket, my companion remarked:

“Don’t you think it would be best to keep this latest discovery to ourselves?”

“Certainly.”

“Because,” he continued, “nobody would be benefited just now by knowing what we know, and to expose the worthlessness of the ‘ore’ might cause a panic. The public is a queer animal, and never gets scared at just the thing you expect will alarm it, but always at something else.”

We had shaken hands and were separating when Hall stopped me.

“Do you believe in alchemy?” he asked.

“That’s an odd question from you,” I replied. “I thought alchemy was exploded long ago.”

“Well,” he said, slowly, “I suppose it has been exploded, but then, you know, an explosion may sometimes be a kind of instantaneous education, breaking up old things but revealing new ones.”