his guests while he proceeded to plan the
details of their visit to the mine.

In an hour or two, the modus operandi had been fully decided upon, and
nothing remained but to fix the night for their expedition, and this
it was thought best to leave to be determined by circumstances the
following week. The instruments needed for taking measurements were to
be taken down beforehand by Houston, and concealed in a safe place
near the mine, and on the night of the examination, he was to go from
the house directly to the mine, where he would be joined by Jack and
Van Dorn, the latter dressed in a suit of Mike's mining clothes, and
personating him as closely as possible.

All arrangements being now as nearly complete as possible, Houston and
Van Dorn bade their host a cordial good night, and walked cheerfully
homeward, in the cool, night air, under the star-lit sky, all
unconscious of a pair of eyes, which from behind a large rock, had
eagerly watched for their appearance, and followed their every
movement.

CHAPTER XXXIII.

As Houston and Van Dorn disappeared around a turn in the road, the
figure of Haight emerged into the starlight from behind a large rock
where he had been concealed most of the time during their stay at the
cabin. Incidently he had seen them on their way to visit Jack, and the
lateness of the hour combined with the direction in which they were
going, aroused his curiosity to such a degree that he followed them at
a distance, and having seen them enter the cabin, his suspicious
nature was at once on the alert.

"I guess I'll find out what in the devil this means," he said to
himself, as he paused behind a rock at a little distance, determined
to ascertain what he could regarding their movements.

It was a long and wearisome watch; once or twice he ventured near the
cabin, to see whether by closer observation he could obtain any clue
to what might be going on within, but the closely shaded window gave
no sign, and beyond an occasional low murmuring of voices, nothing
disturbed the silence, except once a low, ominous growl from Rex, as
he caught sight of Haight's skulking figure from his station just
outside the door.

When at last the door opened, and Houston and Van Dorn stepped forth
into the calm night, the lynx-eyed watcher failed to detect anything
beyond a friendly leave-taking, after which the two walked homeward,
chatting in the most commonplace manner imaginable.

"By George!" he s