What the instrument was I could not tell, but the sound seemed more nearly to resemble that of a violin than anything else of which I could think.
When we first heard it the strains were gentle, sweet, caressing and full of an infinite depth of feeling, but in a little while its tone changed, and it became a magnificent march, throbbing upon the air in stirring notes that set our hearts beating in unison with its stride and inspiring in us a courage that we had not felt before.
Then it drifted into a wild fantasia, still inexpressibly sweet, and from that changed again into a requiem or lament, whose mellifluous tide of harmony swept our thoughts back again to the earth.
"I can endure this no longer," I said. "I must see who it is that makes that music. It is the product of a human heart and must come from the touch of human fingers."
We carefully shifted our position until we stood in the blaze of light that poured out of the door.
The doorway was an immense arched opening, magnificently ornamented, rising to a height of, I should say, not less than twenty or twenty-five feet and broad in proportion. The door itself stood widely open and it, together with all of its fittings and surroundings, was composed of the same beautiful red metal.
Stepping out a little way into the light I could see within the door an immense apartment, glittering on all sides with metallic ornaments and gems and lighted from the center by a great chandelier of electric candles.
In the middle of the great floor, holding the instrument delicately poised, and still awaking its ravishing voice, stood a figure, the sight of which almost stopped my breath.
It was a slender sylph of a girl!
A girl of my own race; a human being here upon the planet Mars!