The sound of the cataract stole with a whispering rush through the underbrush, for the water was low at midsummer, and a good deal of it was diverted to the mill, which was working busily away, with its big water-wheel going round and round.

Nils paused close to the mill, and peered intently into the rushing current; but nothing appeared. Then he stole down to the river-bank, where he seated himself on a big stone, barely out of reach of the spray, which blew in gusts from the cataract. He sat for a long while motionless, gazing with rapt intentness at the struggling, foaming rapids, but he saw or heard nothing.

Then all of a sudden it seemed to him that the air began to vibrate faintly with a vague, captivating rhythm. Nils could hear his heart beat in his throat. With trembling eagerness he unwrapped the violin and raised it to his chin.

Now, surely, there was a note. It belonged on the A string. No, not there. On the E string, perhaps. But no, not there, either.

A flash, surely, through the water of a beautiful naked arm.

And there--no, not there--but somewhere from out of the gentle rush of the middle current there seemed to come to him a marvellous mist of drifting sound--ineffably, rapturously sweet!

With a light movement Nils runs his bow over the strings, but not a ghost, not a semblance, can he reproduce of the swift, scurrying flight of that wondrous melody. Again and again he listens breathlessly, and again and again despair overwhelms him.

Should he, then, never see the Nixy, and ask the fulfilment of his three wishes?