Carefully packed in the car were large numbers of the most powerful infernal machines, ingeniously designed to effect the most awful destruction if hurled into a thickly-populated centre. Piled in the smallest possible compass were square steel boxes, some filled with mélinite, dynamite, and an explosive strongly resembling cordite, only possessing twice its strength, each with fulminating compounds, while others contained picric acid fitted with glass detonating tubes. Indeed, this gigantic engine, which might totally wreck a city and kill every inhabitant in half an hour while at an altitude of 6½ miles, had rightly been named by the Pole who had perfected Tissandier's invention--"The Demon of War."
While the two officers of the Russian balloon section, both experienced aëronauts, were finally examining minutely every rope, ascertaining that all was ready for the ascent, away on Blackford Hill one man, pale and determined, with coat and vest thrown aside, was preparing a counterblast to the forthcoming attack. Under cover of the clump of trees, but with its muzzle pointing towards Bridgend, a long, thin gun of an altogether strange type had been brought into position. It was about four times the size of a Maxim, which it resembled somewhat in shape, only the barrel was much longer, the store of ammunition being contained in a large steel receptacle at the side, wherein also was some marvellously-contrived mechanism. The six gunners who were assisting Mackenzie at length completed their work, and the gun having been carefully examined by the gallant man in charge and two of the officers who had been in the tent with the General during the midnight consultation, Mackenzie, with a glance in the yet hazy distance where the enemy had bivouaced, pulled over a small lever, which immediately started a dynamo.
"In three minutes we shall be ready for action," he said, glancing at his watch; and then, turning a small wheel which raised the muzzle of the gun so as to point it at a higher angle in the direction of the sky, he waited until the space of time he had mentioned had elapsed.
The officers stood aside conversing in an undertone. This man Mackenzie had invented this strange-looking weapon, and only one had been made. It had some months before been submitted to the War Office, but they had declined to take it up, believing that a patent they already possessed was superior to it; yet Mackenzie had nevertheless thrown his whole soul into his work, and meant now to show his superiors its penetrative powers, and put its capabilities to practical test. Again he glanced at his watch, and quickly pulled back another lever, which caused the motor to revolve at twice the speed, and the gun to emit a low hissing sound, like escaping steam. Then he stepped back to the officers, saying--