The commander gave an order. A man on duty in the gondola thrust down a lever, Instantly the gas in several of the ballonets was withdrawn and forced under great pressure into a strong metal tank. This answered to the old-fashioned method of releasing gas from a balloon by means of an escape valve, but with a vast difference. The hydrogen was not wasted; it was merely stored for further service.
Down dropped the airship to less than a thousand feet. Von Eitelwurmer, leaning over the sill of the large scuttle, peered downwards. By means of a pair of powerful night-glasses he could locate his position with great accuracy. He recognised most of the conspicuous land marks of Barborough, in spite of their unfamiliar appearance when viewed from a height. There was the town-hall—a pile of smoke blackened stonework. The railway station with its web of steel lines radiating in four different directions; the huge factories, working day and night at high pressure; the main thoroughfares, rendered even more pronounced by the blue flashes of the electric tram-cars. The Zeppelin had the town at its mercy.
Ober-leutnant von Loringhoven was also examining the scene beneath him. He had no occasion to consult the spy. He knew quite as much as von Eitelwurmer of the topography of the district; thanks to the accurate air-maps supplied by the German government.
"Now, watch!" he exclaimed, at the same time holding up four fingers as a sign to the airman at the firing apparatus to release the missiles of destruction.
Von Eitelwurmer held his breath. He clearly heard the four metallic clicks as the man released the bombs at quick intervals. Seven seconds after the first had left the dropping apparatus a lurid flash threw the underside of the enormous envelope into an expanse of reflected light. A roar like the concentration of half a dozen thunder peals tore the air, followed by the rumbling of falling masonry. The other explosions took place in rapid succession, causing the Zeppelin to sway and rock in the violently disturbed atmosphere.
The place where the bombs had burst was hidden in a thick pall of smoke and dust. Tongues of red and yellow flames flickered through the vapour.
"Two more," ordered von Loringhoven.
By this time the Zeppelin, forging ahead, was nearly a quarter of a mile from the scene of her first attempt. The objective was a purely conjectural one, for the missiles burst in a street in one of the poorer quarters of the town.
"Two more!"
The two bombs were released, but only one exploded. The other failed to detonate, but the raid was over. In a little over a minute and a half death had been poured upon the unprepared town.