In the living-room below they heard it, Dan and Kate Cumberland.  All day she had sat by the fire which still blazed on the hearth, replenished from time to time by the care of Wung Lu.  She had taken up some sewing, and she worked at it steadily.  Some of that time Dan Barry was in the room, sitting through long intervals, watching her with lynx-eyed attention.  Very rarely did he speak—­almost never, and she could have numbered upon her two hands the words he had spoken—­ay, and she could have repeated them one by one.  Now and again he rose and went out, and the wolf-dog went with him each time.  But towards the last Black Bart preferred to stay in the room, crouched in front of her and blinking at the fire, as if he knew that each time his master would return to the fire.  Then, why leave the pleasant warmth for the chilly greyness of the day outside?

There he remained, stirring only now and then to lift a clumsy paw and brush it across his eyes in an oddly human gesture.  Once or twice, also, he lifted that great, scarred head and laid it on her knees, looking curiously from her busy hands to her face, and from her face back again to her work, until, having apparently assured himself that all was well, he dropped his head again and lay once more motionless.  She could see him open a listless eye when the master entered the room again.  And with each coming of Dan Barry she felt again surrounded as if by invisible arms.  Something was prying at her, striving to win a secret from her.

As the day wore on, a great, singing happiness rose in her throat, and at about the same time she heard a faint sound, impalpable, from the farther side of the room where Dan Barry sat.  He was whistling.

A simple thing for a man to do, to be sure, but the astonishment of it nearly stopped the heart of Kate Cumberland.  For in all her life she had never before heard him whistle except when he was in the open, and preferably when he was astride of the strength and the speed of Satan, with Black Bart scouting swiftly and smoothly ahead.  But now he whistled here by the warmth of the fire.  To be sure the sound was small and thin, but there was such music in it as she had never heard before.  It was so thin that it was almost ghostly, as if the soul of wild Paganini played here on a muted violin.  No tune that might be repeated, but as always when she heard it, a picture rose before the eyes of Kate.  It wavered at first against the yellow glow of the firelight.  Then it quite shut out all else.

It was deep night, starry night.  The black horse and his rider wound up a deep ravine.  To one side a bold mountain tumbled up to an infinite height, bristling with misshapen trees here and there, and losing its head against the very stars.  On the other side were jagged hills, all carved in the solid rock.  And down the valley, between the mountains and the stars, blew a soft wind; as if that wind made the music.  They were climbing up, up, up, and now they reach—­the music rising also to a soft but triumphant outburst—­a high plateau.  They were pressed up against the heart of the sky.  The stars burned low, and low.  Around them the whole earth seemed in prospect at their feet.  The moon burst through a mass of clouds, and she saw, far off, a great river running silver through the night.