Corporal Rand pursed his lips. “But one thing is slowly dawning upon me.”

“What?” asked Sandy breathlessly.

“That MacGregor’s wife was right, that MacGregor didn’t take Dewberry’s money, or the small poke he had around his neck.”

“But if he didn’t take it, who did?” Dick inquired.

“Frischette himself might have taken it.”

“Surely MacGregor had something to do with it,” argued Sandy.

Corporal Rand rose and walked slowly across the floor to a little table, where he helped himself to a glass of water. He turned and regarded the boys thoughtfully.

“Here is a supposition that may throw a little light on what actually occurred. ‘Rat’ MacGregor, as we have reason to believe, was the first person to have designs upon Dewberry. He planned the robbery. He drugged his victim. Evidently murder did not enter into his calculations. When all was still in the room, MacGregor crept over to Dewberry’s bunk to commit the robbery.

“In some way his plans went wrong. Perhaps the drug had not proved sufficiently potent. While taking the money and poke, let us say, Dewberry woke up. Perhaps Dewberry made some slight exclamation or sound, which terrified MacGregor and which also might have aroused some other sleeper in that room. In desperation, we will assume, MacGregor murdered Dewberry, but is surprised in the act by this other person who had awakened. Just for the sake of my theory, we will say that that person was Frischette, that in some way he got the ‘drop’ on MacGregor, compelling him to hand over the money and poke and then forcing him to leave the place immediately.”

“Yes, that is plausible,” agreed Dick. “But why Frischette? There were other persons in the room beside him. Why do you think that Frischette may be the guilty one?”

“Because Frischette is planning to leave the country. He claims that he had made a lot of money up here, and is now giving his business to the boy, Fontaine, for a small consideration. That in itself is suspicious. Frischette’s determination to go ‘outside’ surprised me because I remember that, less than a year ago, he confided to me his intention to build three new road-houses here in the North.”

“When is he planning to leave?” asked Sandy.

Corporal Rand smiled reminiscently.

“He expected to go this week, but he has changed his mind since my last talk with him. As a personal favor to me, he has consented to postpone his journey until this little mystery has been cleared up.”

“But do you think that Frischette is aware that you suspect him of the theft?”

“No, I believe not. I merely told him that he would be of invaluable assistance to me in solving this case, and that the mounted police would be deeply indebted to him if he would consent to remain here for a few weeks longer.”

Dick and Sandy both laughed.

“I’ll bet he’s worried stiff,” grinned the latter, “that is, if he’s really the thief. By the way, corporal, how much money did this Dewberry have in his possession at the time of the murder?”

“There’s no way of determining the exact amount,” Rand answered. “Probably several hundred dollars in cash.”

“I wouldn’t think that that would be sufficient bait to tempt MacGregor.”

“There was the poke. Don’t forget that.”

“But you said it was a small one. Perhaps there wasn’t more than a few hundred dollars in nuggets and gold dust.”

“I’m not sure that it was gold.”

“What makes you say that?”

“Well, it was a very small poke. That much I know. It was almost too small for a prospector’s pouch. As you have suggested, if it contained nuggets, there would scarcely be a fortune there—hardly enough to tempt MacGregor. MacGregor would never have taken the chance he did for the small amount involved. He was naturally a coward, a sneaking human rat, and only a big stake could have induced him to gather sufficient courage to make the effort. After reasoning it all out, I have come to the conclusion that MacGregor must have known what that poke contained: Something infinitely more valuable than gold.”

“More valuable!” exclaimed Dick.

“Yes. Why not? Precious stones—or a secret of some sort worth thousands of dollars.”

Sandy sat up, clutching the sides of his chair.

“I’ll say this is getting interesting. You’re arousing my curiosity, corporal. I love a mystery.”

“Well, you have one here,” smiled Rand. “The morning after the murder I came to the conclusion that it would not be a very difficult case. However, it seems that I was wrong. Apparently, ‘Rat’ MacGregor is not the only person involved. Before we sift this thing to the bottom, we may discover that many persons are implicated. It is one of the most mysterious, unusual cases with which I have ever had to deal.”

“How do you purpose to work it all out?”

“I’m almost wholly at a loss to know. I haven’t a great deal to go on. It occurred to me that you boys might be able to pick up information that I couldn’t get myself. You may be able to find a clew. In the meantime, I’m going over to Crooked Stick River—the place where Dewberry came from just before the murder—and question some of the people there. Perhaps Dewberry had a friend or two in whom he confided. Certain it is that the contents of that poke has been seen by someone. Otherwise, to use a well known expression, MacGregor never would have been ‘tipped off.’”

“Don’t you suppose that Dewberry might have told MacGregor about his secret?” asked Dick.

“Scarcely likely. MacGregor was hardly the type of person in whom one would confide. He was a notorious character here in the North. He had a very unsavory reputation. At various times he had been implicated in certain questionable undertakings, and once had served a term in jail.”

“You think, then, that MacGregor had been following Dewberry?”

“Yes, awaiting his opportunity. He’d learned of the secret. But I’m positive that Dewberry gave him no information at all.”

Thus far Toma, naturally reticent, had taken no part in the conversation. He sat rigid in his chair, eyes wide with interest, nothing escaping him. Suddenly he drawled forth:

“When you want us go over this fellow Frischette’s place?” he asked.

“Tomorrow, if you will,” answered the corporal. “Arrange to stay there for three or four days. Then come back here to meet me.”

“I know this young fellow, Fontaine, you talk about,” Toma informed them. “One time we pretty good friends. We go to school one time at Mission. If he know anything, me pretty sure him tell Toma.”

“Good!” exclaimed Corporal Rand. “I’m glad to hear that, Toma. Your friendship with Fontaine may be the means of solving this mystery. If Frischette is implicated, Fontaine must be aware of it.”

The policeman rose to his feet again.

“Well, I guess you understand what’s to be done. If you’ll excuse me, I’ll hurry away now. I want to see Inspector Cameron for a few minutes before I go on to the Crooked Stick.”

He turned and shook hands with each of the boys in turn.

“Well, good luck to you. I hope you’ll like your new role of police detectives. When you return, you’ll probably find me here awaiting you.”

On the evening of the following day, the three boys, dressed for the part, arrived at Frischette’s road-house. It had been a warm afternoon and the boys were weary as they rode up to the well known stopping place and slowly dismounted. Sandy paused to wipe the