At the end of five minutes the curtain fell again. The flying, panic-stricken pickpocket huddled down once more with a frightened curse. But London was no longer alarmed. A passing glimpse of the aerophane had been seen, and better informed folks knew what was taking place. Presently another explosion followed, tearing the curtain away over Hampstead; for the next two hours the explosions continued at short intervals. There were tremendous outbursts of cheering whenever the relief came. Presently a little light seemed to be coming. Ever and again it was possible for a man to see his hands before his face. Above the fog banks a wrack of cloud had gathered, the aerophane was coated with a glittering mist. An hour before it had been perfectly fair overhead. Then it began to rain in earnest. The constant explosions had summoned up and brought down the rain as the heavy discharge of artillery used to do in the days of the Boer War. It came down in a drenching stream that wetted the occupants of the aerophane to the skin. They did not seem to mind. The exhilaration of the fresh sweet air was still in their veins, they worked on at their bombs till the last ounce of the high explosives was exhausted. And the rain was falling over London. Wherever a hole was torn in the curtain, the rain was seen to fall--black rain as thick as ink and quite as disfiguring. The whole city wore a suit of mourning. [Illustration: Wherever a hole was torn in the curtain, the rain was seen to fall.] "The cloud is passing away." Eldred cried. "I can see the top of St. Paul's." Surely enough, the cross seemed to lift skyward. Bit by bit and inch by inch the panorama of London slowly unfolded itself. Despite the sooty flood--a flood gradually growing cleaner and sweeter every moment--the streets were filled with people gazing up in fascination at the aerophane. The tumult of their cheers came upwards. It was their thanks for the forethought and scientific knowledge that had proved to be the salvation of London. As a matter of fact, the high explosives had only been the indirect means of preserving countless lives. The conjuring up of that heavy rain had been the real salvation. It had condensed the fog and beaten it down to earth in a sooty flow of water. It was a heavy, sloppy, gloomy day, such as London ever enjoys the privilege of grumbling over, but nobody grumbled now. The blessed daylight had come back, it was possible to fill the lungs with something like pure air once more, and to realise the simple delight of living. Nobody minded the rain, nobody cared an atom for the knowledge that he was a little worse and a little more grimy than the dirtiest sweep alive. What did it matter so long as everybody was alike? Looking down, the trio in the aerophane could see London grow mad, grave men skipping about in the rain like school-boys at the first fall of snow.