"Well, your business has interested me greatly, Herr Straus," calmly replied my companion, "and I congratulate you upon the ingenious method by which you got a sight of the Kershaw aeroplane at an early hour this morning. I was at Lochindorb with you--and rather cold waiting, wasn't it?" The man now recognised gave vent to a quick imprecation. "I see you've just developed that photograph you took in secret as she sailed within twenty yards of you! But I shall trouble you to give it over to me, together with the rough sketch I see, and your written description of our new military invention," he said, with mock politeness. "I don't know you--and I shall do nothing of the sort." "I know you, Karl Straus, as a spy of Germany," exclaimed my friend, with a grin. "Your reputation for ingenuity and cunning reached us from France"; and snatching up the sheet of foolscap he turned to me, saying, "Listen to this, Jack," and while the German agent stood biting his lips in chagrin at being discovered at the eleventh hour, my friend read aloud the spy's report, as follows: "The upper plane of the Kershaw aeroplane is somewhat curved, with an upward curve at the front. The side planes are composed of a light framework covered with a number of small squares of some light material, each stretched on a light frame hinged to the main frame at the rear end of each. To the front end is fastened a strong silken cord. These cords are all fastened at their lower ends to a large ring. To this is attached a wire rope, which passes over a pulley-wheel at the end of a species of outrigger, and thence into the cigar-like body of the car. From what I have observed when the machine is in flight, it is evident to me that the steersman (who sits at the fore part of the car) is able to manipulate these by means of levers, so that the numerous flaps forming the surface of the side planes can be opened and closed at will.