His horse was the one friend in whom he would trust.

He at least would never betray or desert him.
Presently Wildfire, having eaten his fill of herbage, came and snuffed at the cave's mouth with a whinny of inquiry.

On hearing Tom's voice, he stepped lightly in, and after standing for a while beside his master, lay down between him and the opening to the cave, so that Tom was well shielded from the keen night air, and could sleep as snugly as in his bed at home.
Sleep he did, and soundly too; for the day's ride had wearied him, and he was of the age and temperament when slumber is seldom wooed in vain.

How long he slept he knew not; but he was aroused at length by a movement of Wildfire.

The horse had lifted his head, and was snorting slightly as if in anxiety or fear.
Tom looked out.