of the gas, that one could drink without hurt the water from which it had been strained. The vapour did not diffuse as a true gas would do. It hung together in banks, flowing sluggishly down the slope of the land and driving reluctantly before the wind, and very slowly it combined with the mist and moisture of the air, and sank to the earth in the form of dust. Save that an unknown element giving a group of four lines in the blue of the spectrum is concerned, we are still entirely ignorant of the nature of this substance.Once the tumultuous upheaval of its dispersion was over, the black smoke clung so closely to the ground, even before its precipitation, that fifty feet up in the air, on the roofs and upper stories of high houses and on great trees, there was a chance of escaping its poison altogether, as was proved even that night at Street Cobham and Ditton.The man who escaped at the former place tells a wonderful story of the strangeness of its coiling flow, and how he looked down from the church spire and saw the houses of the village rising like ghosts out of its inky nothingness. For a day and a half he remained there, weary, starving and sun-scorched, the earth under the blue sky and against the prospect of the distant hills a velvet-black expanse, with red roofs, green trees, and, later, black-veiled shrubs and gates, barns, out- houses, and walls, rising here and there into the sunlight.But that was at Street Cobham, where the black vapour was allowed to remain until it sank of its own accord into the ground. As a rule the Martians, when it had served its purpose, cleared the air of it again by wading into it and directing a jet of steam upon it....
