Our inquiries in Blair Atholl had had a negative result. In the long, old-fashioned Blair Arms Hotel Ray had made a number of searching inquiries, for though two officers of the Ballooning Department lived there, and had been conducting the experiments in Blair Park, it was plain that the machine had never yet taken flight. So the pair of mysterious Germans, whose names we discovered in the visitors' book, had either obtained the details they wanted or had left the neighbourhood in disgust. It was at my friend's suggestion that we had hired the car from Perth, and had now set out upon a tour of discovery in the wildest and least frequented districts of the Highlands--some of which are in winter the most unfrequented in all Great Britain. Something--what I know not--had apparently convinced him that the tests were still in progress. "And where the trials are taking place we shall, I feel certain, find this inquisitive person Karl Straus," he declared. "From Berlin, through a confidential source, I hear that it was he who obtained the German General Staff photographs and plan of the new French aeroplane that was tried down in the Basque country last May. He's an expert aeronaut and engineer, and speaks English well; our object is to discover his whereabouts." In pursuance of this quest we visited the various hotels on our way north. The "Loch Ericht" at Dalwhinnie we found closed, therefore we went on to Newtonmore, and by taking luncheon at the hotel there ascertained that there were no visitors who might be either British military officers or German spies. In the gloomy, frosty afternoon we, a month after the affair down at Maldon, sped up the Speyside through dark pine forests and snow-covered moorland till we found ourselves in the long grey street of Kingussie, where we halted at the Star Hotel, a small place with a verandah, very popular in summer, but in winter deserted. Leaving me to warm myself at the fire, Ray crossed to the telegraph office to despatch a message, and afterwards I saw him enter a small shop where picture post-cards were sold. For a quarter of an hour he remained inside, and then went to another shop a few doors further down. Afterwards he rejoined me, and as we remounted into the car I saw that his face wore a dark, puzzled expression. "Anything wrong?" I inquired, as we sped away through the firs towards Loch Alvie and Aviemore. "No," he replied. Then, after a pause, he asked, "You once used to ride a motor-cycle, didn't you, Jack?" I replied in the affirmative; whereupon he said that it would be necessary for me to hire one, an observation which somewhat mystified me. And for the next hour we roared along over the loose, uneven road through Aviemore, where the chief hotel was, of course, closed, and on over Dulnan Bridge, that paradise of the summer tourist; then turning to the right past the post office, until we were soon "honk-honking" up the wide main street of Grantown.