"Now," said the Sergeant, "there are one or two points I want explained, and as you know the man, it's possible you can help me. How did he come to be here with only about three days' rations?"

"I can answer that," said Harding. "He was in the habit of staying at the Indian village we told you of. We saw tracks coming from it when we were there the day before the blizzard began."

"A white man's tracks? Why did you go to the village?"

"I believe they were," Blake replied. "We went to look for provisions and didn't get them, because the place was empty."

"Then how do you account for the fellow's being there alone?"

"I can't account for it," Blake said quietly.

Lane turned to Harding, who had a theory but was not prepared to communicate it to the police.

"It's certainly curious," he remarked.

"We'll start for the village to-morrow."

"As the Indians are away, there won't be much to be learned," Benson suggested.

"They may have come back. Anyway, it's my business to find out all I can."

Soon afterwards they went to sleep and rising an hour or two before daylight broke camp and turned back across the hills. The march was rough and toilsome, and when they camped at night fatigue and drowsiness checked conversation, but Blake's party were sensible of a difference in Lane's manner. It had become reserved and he had a thoughtful look. Reaching the village one evening, they were surprised to find that some of the Indians had returned and after supper Lane summoned them into the tepee he occupied. Emile interpreted, but he had some difficulty in making himself understood, for which Harding was inclined to be thankful.

The Sergeant began by explaining the authority and business of the North-West Police, of whom it appeared one or two of the Indians had heard, after which he made Emile ask them if they knew Clarke. One of them said they did and added that he stayed with them now and then.

Lane next asked why they took him in and the Indian hesitated.

"He was a big medicine man and cured us when we were ill," he replied.

"Do you know these white men?" Lane asked, indicating Blake's party.

An Indian declared that they had never seen them, though he added that it was known they were in the neighbourhood. Being questioned about this, he explained that about the time of Clarke's arrival one of the tribe had come in from the North, where he had met a half-breed who told him that he had travelled some distance with three white men who were going to the settlements. Knowing the country, they had calculated that the white men could not be very far off. As he heard this Harding felt anxious. He saw where Lane's questions led, and that the Sergeant meant to sift the matter thoroughly. There was not much cause to fear that he and his friends would be held responsible for Clarke's death, but he suspected things he did not wish the police to guess, and the Indians might mention having seen a white man's footprints on the occasion when he had forcibly taken Clarke away.

Owing perhaps to their difficulty in making themselves understood, nothing was, however, said of this, and by and by Lane asked--

"How was it you left the white man in your village by himself?"

The Indians began to talk to one another, and it was with some trouble Emile at length elicited an answer.

"It is a thing that puzzles us," said one. "The white man came alone and told us he had seen tracks of caribou three days' journey back. As we had no meat and our fish was nearly done, six of us went to look for the deer."

"Six of you?" said Lane. "Where are the rest? These tepees would hold a good many people."

"They are hunting farther North," answered the man. "When we got to the place the white man told us of we could see no caribou tracks. As he was a good hunter, we thought this strange, but we went on, because there was another muskeg like the one he spoke of and we might not have understood him. Then the snow came and we camped until it was over and afterwards came back, finding no deer. When we reached the tepees, he had gone and we do not know what has become of him. We could not follow because the snow had covered his trail."

"He is dead," Lane told them. "I found him frozen some days ago."

Their surprise was obviously genuine and Lane was quick to notice signs of regret. He imagined that Clarke had been a person of some importance among them.

"Tell them I don't want them any more," he said to Emile, and when the Indians went out turned to Benson. "You had better give me all the information you are able about the man."

Benson told him as much as he thought judicious, after which Lane sat silent for a time. Then he said, "There is no reason to doubt that he came to his death by misadventure. I don't quite understand what led him to visit these fellows, but after all that doesn't count."

"It isn't very plain," Benson agreed. "Is there anything else you wish to know?"

"No," said Lane, looking at him steadily. "You can take it that this inquiry is closed; we'll pull out first thing to-morrow." He beckoned Walthew. "Now we're here, we may as well find out what we can about these fellows and how they live. It will fill up our report, and they like that kind of information at Regina."

When the police had left the tepee Harding turned to his companions with a smile. "Sergeant Lane is a painstaking officer, but his shrewdness has its limits, and there are points he seems to have missed. It would have been wiser not to have let Clarke's coat out of his hands until he had searched it."

"Ah!" said Blake sharply. "You emptied the pockets?"

"I did; I allow my action was hardly justifiable, but I thought it better that the police shouldn't get on the track of matters that haven't much bearing on Clarke's death. I found two things and they're both of interest to us. We'll take this one first."

He drew out a metal flask and when he unstoppered it a pungent smell pervaded the tepee. "Crude petroleum," he explained. "I should imagine the flashpoint is low. I can't say how Clarke got the stuff when the ground's hard frozen, but here it is."

"Isn't a low flash-point a disadvantage?" Benson asked. "It must make the oil explosive."

"It does, but all petroleum's refined and the by-products they take off, which include gasoline, fetch a remarkably good price. Shake a few drops on the end of a hot log and we'll see how it lights."

A fire burned in a ring of stones in the middle of the tepee and Benson carefully did as he was told. Hardly had the oil fallen on the wood than it burst into flame.

"As I thought!" said Harding. "I suspect the presence of one or two distillates that should be worth as much as the kerosene. We'll get the stuff a.n.a.lysed later, but you had better stopper the flask, because we don't want the smell to rouse Lane's curiosity. The important point is that as I've reasons for believing the oil is fresh from the ground, Clarke must have found it shortly before the blizzard overtook him.

That fixes the locality and we shouldn't have much trouble in striking the spot when we come back again." His eyes sparkled as he concluded: "It's going to be well worth while; this is a big thing."

Blake did not feel much elation. His was not a mercenary nature, and he had all along thought his comrade too sanguine, though he meant to back him.

"In a way, it was very hard luck for Clarke," he said. "If you're right in your conclusions, he's been searching for the oil for several years, and now he was cut off just when it looks as if he'd found it."

"You don't owe him much pity. What would have happened if we hadn't met the police?"

"It's unpleasant to think of. No doubt we'd have starved to death."

"A sure thing!" said Harding. "It hasn't struck you that this was what he meant us to do?"

Blake started. "Are you making a bold guess, or have you any ground for what you're saying?"

"I see you'll have to be convinced. Very well; in the first place, the man would have stuck at nothing, and I've already tried to show you that he'd something to gain by Benson's death." He turned to the latter. "I suspected when we took you away from him that you were running a risk."

"I was running a bigger one before that, if you can call a thing a risk when the result's inevitable," Benson rejoined. "The pace I was going would have killed me in another year or two, and even now I'm half afraid----" He paused for a few moments with sombre face and knitted brows; and then resumed thoughtfully: "I believe you're right, Harding, but you haven't told us how he proposed to get rid of me."

"I'm coming to that. There was, however, another member of this party who was in his way, and he made his plans to remove you both."

"You mean me?" Blake broke in. "It's possible, but I don't altogether see how he'd profit."

"First, let's look at what he did. As soon as he reached the village he heard that we had started from the Hudson's Bay post. It wouldn't be difficult to calculate how long the stores we could carry would last, and he'd see that the chances were in favour of our calling at the village for provisions. Presuming on that, he sent his friends away to look for caribou which they couldn't find. Recollect that they owned to being puzzled because he was a good hunter. Then he cleared out by himself, but I believe that if there was any food left in the place he carefully hid it."

The others felt that their comrade was taking something for granted, but they believed his suspicions were correct. They, however, made no comment, and Harding went on, looking at Blake--

"Now I'll show you how he would have profited. I found this in his pocket."

He took out a letter which he gave to Blake, and the latter started as he recognized the writing. It was from Colonel Challoner to Clarke.