That the secret agent proposed to reserve the services of the young aviators to himself thereafter and during their stay in this locality was made manifest when he told them the next day to make ready for a quick departure in the biplanes. As usual, he furnished no advance particulars. It appeared that Schneider was also to figure in the expedition in a capacity indicated by his employment of oiling and polishing a service rifle of the 16-shot brand, and the display of a pair of long-barreled revolvers stuck in his belt. "He looks like an arsenal on parade," commented Billy when the red-haired flyer, in war-like array, passed on the way to conference with Roque. "There is no peaceful intent about that get-up," admitted Henri. "And let me make another prediction," he continued, still proud of his last previous success as a prophet, "this isn't going to be any pink tea or garden party to which we're going." "What a head you have," said Billy, beaming with mock admiration. There was a decided lull in the fighting this day--the ninth since the continuous combat had been commenced, as the soldiers of the two armies were apparently resting on their arms. Some fresh planning, no doubt, was in progress. The boys wandered around the camp, restlessly anticipating the expected summons from Roque. The latter, however, had not picked daylight in which to operate, for it was long past nightfall when Schneider sought and advised the boys that the starting time had arrived. The moon was working full time when the biplanes set their course, following the turnpike toward La Fere. Above a farm, which had practically been razed, and on the edge of a ruined district, both Roque and Schneider signaled the pilots to lower the flight, and the biplanes circled groundward, landing near a row of stunted willow trees. They showed no lights, and with the motors silenced lay hidden behind a huge pile of debris, close to a wrecked dwelling, so close that the full moon shining through the shattered roof gave the aviators a dim vision of hopeless confusion, cooking pots and children's toys, broken clocks and tables, knives, forks and books strewn on the floor, beds and everything awry. Billy and Henri had as yet no inkling of the purpose of this mysterious proceeding in which they were engaged. Their companions did not seem to be in a hurry, either, to enlighten them. Roque and Schneider appeared intent in upward gaze, perhaps hoping that the moon and a dense bank of clouds forming near would soon come together. As a matter of fact, a total eclipse of the great orb above did follow, with the effect of the sudden blowing out of the one lamp in an otherwise dark room. Curious to relate, it was not long until the moon was replaced in the now black canopy by a small but quite silvery brilliant imitation of the big illuminant. The diamond-shaped light in the lowering sky flashed this way and that, as if responding to the manipulation of an aërial cable.