"It hasn't got the glider," muttered Foulet and his tone was tinged with disappointment. But hardly had he spoken when, from one of the myriad roof-tops below us, rose a swift streak of shadow. So fast it flew, with such unbelievable speed, that to our eyes it was little more than a blur; but-- "The glider!" Brice gasped. "My God! How did he do it?" We stared, silent with amazement. The airplane, that only a second before had flown alone, now was towing a glider--a glider that had arisen, as if by magic, from the housetops! Another instant and we had piled into the cockpit of the tri-motored plane and were off on our pursuit. That pursuit that led us on and on till, as the sun sank behind us, we found ourselves above the illimitable, tawny wastes of the great Arabian Desert. And now--what? All day long, as I have said, the plane we were pursuing had maintained, but never increased, the distance between us. Each hour had brought us renewed hope that the next hour would bring capture--or at least some definite clue, some shred of information. But the plane, still towing its glider, had gone on and on, steadily, imperturbably. And we dared not open fire and attempt to bring it down for fear of destroying our one meager chance of following it to its destination. * * * * * And now it had vanished. Suddenly, unaccountably it had taken on that terrific burst of speed which I have described. In ten minutes it had become a speck on the far horizon--in another instant it was gone. We were alone. Night was falling. If we turned back our gas might bring us to safety. If we went on--what? I turned to my companions. Foulet still maintained his non-committal attitude, but Brice was deeply disappointed and worried. His ruddy English face was knotted in a scowl and his blue eyes were dark. Quickly he jerked his head back. We understood. Of course, turning back was the only thing to do; to go on was absurd. Our quarry had totally disappeared. But it was heart-breaking. Once again we had been fooled and outwitted. Our disappointment filled that tiny cockpit like a tangible mist. Brice threw over the stick with a gesture of disgust. In response our right wing lifted a bit, seemed to shake itself, then settled--and the plane continued on its course. Brice's eyes flickered with surprise. He shoved the stick back, threw it over again, but toward the opposite side. Obediently our left wing lifted as if to bank, a shudder passed through it, it dropped, the plane leveled, and went on.