A few men would point skywards, others would follow their example, till every soldier in the square was gazing in the air. Then above the hum of suppressed excitement came the unmistakable buzz of an aerial propeller. "Air-craft!" ejaculated Kenneth. "Taubes, most likely," added his companion; "otherwise the troops would be blazing away instead of merely looking on." The words were hardly out of his mouth when the scene underwent a complete change. Horses plunged and reared, some falling and kicking madly on the ground. Men ran hither and thither, seeking shelter, while several of them pitched upon their faces. Yet not a sound was heard of an explosion. A mysterious and silent death was stalking amidst the German transport. Overhead the drone of the propeller increased, yet the aeroplane was invisible from the lads' outlook. Something struck the stones of the courtyard a few feet from their window. It was a small featherless steel arrow, one of thousands that a French aviator had let loose upon the astonished and terrified Germans. Simultaneously there was a crash in the room. Turning, the occupants made the discovery that three of the darts had completely penetrated the tiles of the roof and had buried themselves three inches deep in the oaken floor. "Keep close to the wall," exclaimed Kenneth; "it is the safest place." "It's all over now," announced Rollo after a brief interval. "There she goes!" He pointed to a monoplane gliding gracefully at an altitude of about five hundred feet. He could just distinguish a tricolour painted on each tip of the main plane. A desultory but increasing rifle-fire announced its departure, and, unruffled, the air-craft sailed serenely out of sight. "Pretty effective weapon," remarked Kenneth, vainly endeavouring to wrench one of the darts from the floor. "They must hit with terrific force. I wonder how they were discharged?" "Simply dropped by the hundred, I should imagine," replied Rollo. "The force of gravity is sufficient to give them a tremendous velocity after dropping a few hundred feet. I guess they've knocked these fellows' time-table out." The drivers and several cavalrymen had now emerged from their hiding-places, and were carrying their less-fortunate comrades from the scene. A few of the latter were moaning, but most of them had been slain outright. The "flechettes", or steel darts, had in several cases struck their victims on the head, and had passed completely through their bodies. In addition to about thirty casualties, nearly a hundred horses were either killed on the spot or were so badly injured that they had to be dispatched. Several of the motor-wagons, too, were temporarily disabled by the terrible missiles. Clearly it was out of the question that the convoy could proceed that day.