Carrigan lowered his flag and gathered himself in tighter.  The accuracy of the other’s marksmanship was appalling.  He knew that if he exposed himself for an instant to use his own rifle or the heavy automatic in his holster, he would be a dead man before he could press a trigger.  And that time, he felt equally sure, would come sooner or later.  His muscles were growing cramped.  He could not forever double himself up like a four-bladed jackknife behind the altogether inefficient shelter of the rock.

His executioner was hidden in the edge of the timber, not directly opposite him, but nearly a hundred yards down stream.  Twenty times he had wondered why the fiend with the rifle did not creep up through that timber and take a good, open pot-shot at him from the vantage point which lay at the end of a straight line between his rock and the nearest spruce and balsam.  From that angle he could not completely shelter himself.  But the man a hundred yards below had not moved a foot from his ambush since he had fired his first shot.  That had come when Carrigan was crossing the open space of soft, white sand.  It had left a burning sensation at his temple—­ half an inch to the right and it would have killed him.  Swift as the shot itself, he dropped behind the one protection at hand, the up-jutting shoulder of shale.

For a quarter of an hour he had been making efforts to wriggle himself free from his bulky shoulder-pack without exposing himself to a coup-de-grace.  At last he had the thing off.  It was a tremendous relief when he thrust it out beside the rock, almost doubling the size of his shelter.  Instantly there came the crash of a bullet in it, and then another.  He heard the rattle of pans, and wondered if his skillet would be any good after today.

For the first time he could wipe the sweat from his face and stretch himself.  And also he could think.  Carrigan possessed an unalterable faith in the infallibility of the mind.  “You can do anything with the mind,” was his code.  “It is better than a good gun.”

Now that he was physically more at ease, he began reassembling his scattered mental faculties.  Who was this stranger who was pot-shotting at him with such deadly animosity from the ambush below?  Who—­

Another crash of lead in tinware and steel put an unpleasant emphasis to the question.  It was so close to his head that it made him wince, and now—­with a wide area within reach about him—­he began scraping up the sand for an added protection.  There came a long silence after that third clatter of distress from his cooking utensils.  To David Carrigan, even in his hour of deadly peril, there was something about it that for an instant brought back the glow of humor in his eyes.  It was hot, swelteringly hot, in that packet of sand with the unclouded sun almost straight overhead.  He could have tossed a pebble to where a bright-eyed sandpiper was cocking itself backward and forward, its jerky