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 analysed 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 ha