It was after a long period of thus lying in dead calm—­with the occasional appearance of a diver on the surface of the shining blue sea—­that Macleod’s sharply observant eye was attracted by an odd thing that appeared far away at the horizon.

“What do you think is that now?” said he, with a smile.

They looked steadfastly, and saw only a thin line of silver light, almost like the back of a knife, in the distant dark blue.

“The track of a seal swimming under water,” Mr. White suggested.

“Or a shoal of fish,” his daughter said.

“Watch!”

The sharp line of light slowly spread; a trembling silver-gray took the place of the dark blue; it looked as if invisible fingers were rushing out and over the glassy surface.  Then they felt a cool freshness in the hot air; the red ensign swayed a bit; then the great mainsail flapped idly; and finally the breeze came gently blowing over the sea, and on again they went through the now rippling water.  And as the slow time passed in the glare of the sunlight, Staffa lay on the still water a dense mass of shadow; and they went by Lunga; and they drew near to the point of Gometra, where the black skarts were sitting on the exposed rocks.  It was like a dream of sunlight, and fair colors, and summer quiet.

“I cannot believe,” said she to him, “that those fierce murders and revenges took place in such beautiful scenes as these.  How could they?”

And then, in the broad and still waters of Loch Tua, with the lonely rocks of Ulva close by them, they were again becalmed; and now it was decided that they should leave the yacht there at certain moorings, and should get into the gig and be pulled through the shallow channel between Ulva and Mull that connects Loch Tua with Loch-na-Keal.  Macleod had been greatly favored by the day chosen at haphazard for this water promenade:  at the end of it he was gladdened to hear Miss White say that she had never seen anything so lovely on the face of the earth.

And yet it was merely a question of weather.  To-morrow they might come back and find the water a ruffled leaden color; the waves washing over the rocks; Ben More invisible behind driving clouds.  But now, as those three sat in the stern of the gig, and were gently pulled by the sweep of the oars, it seemed to one at least of them that she must have got into fairyland.  The rocky shores of Ulva lay on one side of this broad and winding channel, the flatter shores of Mull on the other, and between lay a perfect mirror of water, in which everything was so accurately reflected that it was quite impossible to define the line at which the water and the land met.  In fact, so vivid was the reflection of the blue and white sky on the surface of the water that it appeared to her as if the boat was suspended in mid-air—­a sky below, a sky above.  And then the beauty of the landscape that enclosed this wonderful mirror—­the soft green foliage above the Ulva rocks; the brilliant