front conditions,
fully appreciated the coaxing, the general manoeuvering, the constant
delicate manipulation of brake and throttle necessary to produce this
result. But his admiration of the fellow's skill was swiftly swallowed up
in eager curiosity and speculation.

Who were they? What were they doing here? Where were they going? At first
he had a momentary fear lest they should see him perched up here on his
point of vantage. Then he realized that the backing of rocks prevented his
figure from showing against the skyline, which, together with the distance
and the clouds of dust stirred up by the car itself, made the danger
almost negligible. So he merely dismounted and, leaning against his horse,
kept the glasses riveted on the slowly moving machine.

The car advanced steadily until it reached a point about a quarter of a
mile from the rough ground and a little distance north of where Buck
stood. Then it stopped, and a capped and goggled head was thrust out of
the tonneau. Buck could make out nothing definite about the face save that
it was smooth-shaven and rather heavy-jowled. He was hoping that the
fellow would alight from the car and show himself more plainly but to his
disappointment the head was presently drawn back and the machine crept
on, swerving a little so that it headed almost due north.

Ten minutes later it halted again, and this time the two men got out and
walked slowly over the sand. Both were clad in long dust-coats, and one
seemed stouter and heavier than the other. Unfortunately they were too far
beyond the carrying power of the binoculars to get anything more clearly,
and Buck swore and fretted and strained his eyes in vain. After a delay of
nearly an hour, he saw the car start again, and followed its blurred image
until it finally disappeared beyond an out-thrust spur well to the
northward.

Stratton lowered his glasses and stood for a moment or two rubbing his
cramped arm absently. His face was thoughtful, with a glint of excitement
in his eyes. Presently his shoulders straightened resolutely.

"Anyhow, I can follow the tracks of the tires and find out what they've
been up to," he muttered.

The difficulty was to descend from his rocky perch, and it proved to be no
small one. He might have clambered down the face of the cliff, but that
would mean abandoning his horse. In the end he was forced to retrace his
steps along the twisting ledge by which he had come.

From his knowledge of the