He had faced too many perils of late to begin to turn coward now.

So long as he felt that he was leading these followers away from the other pass to be taken by his comrade, he cared for nothing else--not even for the discovery he once made that they were three in number, though Lord Claud had calculated that they would only be two.
Sometimes Tom noted that his guide would look back, and more than once he fancied that he detected him signalling to those below.
This aroused in his mind a doubt of the fellow's fidelity; but there was nothing to be done now.

They were in the midst of trackless snow plains, ice slopes, and precipices.

He must perforce trust to the leading of the guide, albeit, if he had been tampered with by those in pursuit, things might look ugly when it came to the moment of attack.
As the hours wore away, Tom began to wish that the situation might declare itself.

The drear wildness of the mountain height oppressed him with a sense of personal insignificance which was rather overwhelming.