He pressed the button down hard. There was the same sharp sound, and a second messenger of destruction sped on its way towards the doomed fortress. [Illustration: "Good God, that is awful." _See page 82._] They saw it strike, and then came the flash, and after that a huge cloud of dust mingled with flying objects that might have been blocks of masonry, guns, or human bodies, rose into the air, and then fell back again to the earth. "There goes one of the angles of the fortification into the sea," said Arnold, as he saw the effects of the shot. "Kronstadt won't be much good when the war breaks out, it strikes me. I suppose they'll be replying soon with a few rifle shots. We'd better quicken up a bit." He went aft to the wheel-house, followed by Colston, and signalled for the three propellers to work at their utmost speed. The order was instantly obeyed; the fan-wheels ceased revolving, and under the impetus of her propellers the _Ariel_ leapt forwards and upwards like an eagle on its upward swoop, rose five hundred feet in the air, and then swept over Kronstadt at a speed of more than a hundred miles an hour. As they passed over they saw a series of flashes rise from one of the untouched portions of the fortress, but no bullets came anywhere near them. In fact, they must have passed through the air two or three miles astern of the flying _Ariel_. No soldier who ever carried a rifle could have sent a bullet within a thousand yards of an object seventy feet long travelling over a hundred miles an hour at a height of nearly four thousand feet, and so the Russians wasted their ammunition. As soon as they had passed over the fortress, Arnold signalled for the propellers to stop, and the fan-wheels to revolve again at half speed. The air-ship stopped within three miles, and remained suspended in air over the opening mouth of the Neva. Then the two after guns were trained upon the fortress, and Colston and Arnold fired them together. The two shells struck at the same moment, one in each of two angles of the ramparts. Their impact was followed by a tremendous explosion, far greater than could be accounted for by the shells themselves. "There goes one, if not two, of his powder magazines. Look! half the fortress is a wreck. I wonder which fired the lucky shot." The man who a year before had been an inoffensive student of mechanics and an enthusiast dreaming of an unsolved problem, spoke of the frightful destruction of life and the havoc that he had caused by just pressing a button with his finger, as coolly and quietly as a veteran officer of artillery might have spoken of shelling a fort.