bit him, and I don't think he would ever
be ungrateful, though I think he feels hurt that you do not place more
trust in him."

"Well, let him prove himself well worthy of my trust," said the Doctor,
bluntly. "I have not found him so ready as he should be in helping me
with my plans."

Here the Doctor became very silent and reserved, and though Bart asked
him several questions, and tried to get him into conversation, he hardly
spoke, but seemed moody and thoughtful till they were close upon the
little camp.

This was hidden from them till they were almost there, for the upper end
of the Horse-shoe Valley was extremely rugged, and their way lay in and
out among heavy blocks of stone that seemed as if they had been hurled
down from the mountain-side.

When they were just about to turn into the narrow opening where the
waggon lay and the horses were tethered, the Doctor stooped down to
examine some fragments that lay loose about their feet, and the
consequence was that Bart went on alone. He was just about to give a
peculiar whistle, one used commonly by himself and the men when they
wished to signal their whereabouts, when he stopped short, half hidden
by the rocks, raised his rifle to his shoulder, and stood ready to fire,
while his face, tanned as it was by the sun, turned of a sickly hue.

For a moment he was about to fire. Then he felt that he must rush
forward and save Maude. The next moment calmer reflection told him that
such help and strength as he could command would be needed, and,
slipping back out of sight, he ran to where he had left the Doctor.

He found him sitting down examining by means of a little
magnifying-glass one of the fragments of rock that he had chipped off,
while his rifle lay across his knee.

He seemed so calm and content that in those moments of emergency Bart
almost shrank from speaking, knowing, as he did, how terrible would be
the effect of his words.

Just then the Doctor looked up, saw his strange gaze, and dropping the
fragments, he leaped to his feet.

"What is it?" he cried; "what is wrong?" and as he spoke the lock of his
double rifle gave forth two ominous clicks twice over.

"They have come round while we have been away," whispered Bart hoarsely.

"They? Who? Our men?"

"No," panted Bart; "the camp is surrounded by Indians."

CHAPTER SIX.

A SURGICAL OPERATION.

Dr Lascelles' first movement was to run forward to the help of his
child, Bart being close