The projectile with which the cannon was loaded was not an instantaneous motor-bomb. It was simply a heavy solid shot, driven by an instantaneous motor attachment, and was thus impelled by the same power and in the same manner as the motor-bombs. The instantaneous motor-power had not yet been used at so great a distance as that between the repeller and the Adamant, and the occasion was one of intense interest to the small body of scientific men having charge of the aiming and firing. The calculations of the distance, of the necessary elevation and direction, and of the degree of motor-power required, were made with careful exactness, and when the proper instant arrived the button was touched, and the shot with which the cannon was charged was instantaneously removed to a point in the ocean about a mile beyond the Adamant, accompanied by a large portion of the heavy boom at which the gun had been aimed. The cannon which had been suspended from the end of this boom fell into the sea, and would have crashed down upon the roof of Crab K, had not that vessel, in obedience to a signal from the repeller, loosened its hold upon the Adamant and retired a short distance astern. Material injury might not have resulted from the fall of this great mass of metal upon the crab, but it was considered prudent not to take useless risks. The officers of the Adamant were greatly surprised and chagrined by the fall of their gun, with which they had expected ultimately to pound in the roof of the crab. No damage had been done to the vessel except the removal of a portion of the boom, with some of the chains and blocks attached, and no one on board the British ship imagined for a moment that this injury had been occasioned by the distant repeller. It was supposed that the constant firing of the cannon had cracked the boom, and that it had suddenly snapped. Even if there had been on board the Adamant the means for rigging up another arrangement of the kind for perpendicular artillery practice, it would have required a long time to get it into working order, and the director of Repeller No. 7 hoped that now the British captain would see the uselessness of continued resistance. But the British captain saw nothing of the kind, and shot after shot from his guns were hurled high into the air, in hopes that the great curves described would bring some of them down on the deck of the repeller. If this beastly store-ship, which could stand fire but never returned it, could be sunk, the Adamant's captain would be happy. With the exception of the loss of her motive power, his vessel was intact, and if the stupid crab would only continue to keep the Adamant's head to the sea until the noise of her cannonade should attract some other British vessel to the scene, the condition of affairs might be altered.