It had been part of his training always to take stock of his surroundings, and the knowledge thus obtained when a few hours previously he had walked into Le Tenetoir aerodrome was now of inestimable service. Carefully avoiding the sentry of the gate, and crawling through a barbed-wire fence, he gained the open, devastated country, for the time being a free man again. But between him and the German lines lay fifty miles of ground firmly held by the victorious Allies. CHAPTER XIV With the Tanks For the second time within twelve hours Derek Daventry made a journey by car to Le Tenetoir aerodrome. On the second occasion it was to give evidence against the airman-spy Count Hertz von Peilfell; but upon arriving at his destination he found that the court-martial had been summoned to no purpose. The prisoner had escaped, and, although his description had been circulated all along the Allied front and over the back-areas, the Count was still at large. Amongst the British airmen the general tone of expression was one of sympathy--as far as sympathy could be extended to a Hun. Von Peilfell was a crack airman; his rôle of spy was quite in accordance with modern warfare, for both British and French air-craft had frequently landed spies well behind the German lines. It was almost unanimously felt that, if Count von Peilfell were to fall, a fitting end to him would be in aerial combat. If he fell on territory occupied by the Allies he would be buried with full military honours; if on soil temporarily held by the Huns, then a British aeroplane would doubtless circle over the funeral-party and drop a wreath bearing a tribute to the crack Hun flyer's prowess. But sterner work was on hand. It was a carefully-kept secret that at dawn on the next day following the spy's escape a frontal attack was to be delivered upon the Huns, still holding a strongly-fortified section of the line--a front of twenty miles, protected on both flanks by broad canals, and defended by mazes of trenches and barbed-wire entanglements. Once this section were pierced, the whole German line would be in danger. Army corps would be practically surrounded and forced to surrender, while a broad wedge would be driven between the Huns in Flanders and those who were stoutly resisting the Franco-American troops in the neighbourhood of Metz. An infantry attack would be too costly. Heavy artillery bombardment would give the Boches an inkling of what was about to develop. On this account the British guns had of late remained comparatively inactive, in order to lull Fritz into a state of false security.