What did he mean? We ate a hasty lunch, and then, mounting into the car, my companion ordered the chauffeur to drive south again past Dulnan Bridge to Duthil, where we turned up to the right and ascended the thickly wooded hill of Lochgorm on that stony road that leads out upon the desolate Muirs of Cromdale. After we had cleared the wood he ordered the man to pull up, for the road was so bad. Descending, we climbed the steep ascent to the summit of a hill, where, after sweeping the surrounding country with a small pair of powerful glasses I carried, I at last discerned the aeroplane heading westward some ten miles distant. Unfortunately, however, the clouds came down upon us, and we quickly found ourselves enveloped in a gradually thickening Scotch mist, while the aeroplane, soon but a faint grey shadow, quickly faded from our gaze. Ray Raymond was ever a dogged person. He decided to descend, and this we did, passing over the other side of the hill for half an hour, progress of course being slow on account of the clouds. Presently a puff of cold wind came up out of the east, and patches of dun-coloured moorland began to appear below through the rents of the fast-breaking clouds; when presently our watchful eyes caught the dull leaden gleam of a sheet of water about three miles ahead, which a look at my map enabled me to recognise as Lochindorb. And just as we were able to locate the spot we again saw the big white-winged aeroplane as she swooped down to the surface of the loch, upon which she floated swanlike and majestic. "Well?" I asked, turning and looking him in the face. "Well, Jack, I've seen it in flight just as you have," he said, "but I've never yet approached it. I've had reasons for keeping away. After to-day, however, there is no longer much necessity for hesitation." "I hardly follow you, old chap," I declared, my eyes still fixed through the glasses upon the aeroplane sailing along the surface of the distant lake. "Probably not," he laughed, "but you'll see the motive of my actions before a few days are over, I hope. Let's go back." And returning to the car he carried me as far as the entrance to Grantown, where he deposited me, and then turning, ordered the man to drive with all speed back to Kingussie. When I re-entered my comfortable hotel I learnt that Goldstein had left by the afternoon train for the south. My interest therefore lay in the new arrival in No. 11, but though I waited up till midnight, he did not return. Just as I was returning to bed I made a curious discovery in my room. Running from the top of the high, old-fashioned mahogany wardrobe, with its heavily ornamented cornice, was a long piece of strong, black cord, which, passing down the side panel, was placed close to the wainscoting, so as to avoid notice, the end being placed beneath the mat outside the door.