have described, had discharged, by means of the gun-like tube he carried, a huge canister over whatever hill, copse, cluster of houses, or other possible cover for guns, chanced to be in front of him. Some fired only one of these, some two—as in the case of the one we had seen; the one at Ripley is said to have discharged no fewer than five at that time. These canisters smashed on striking the ground—they did not explode—and incontinently disengaged an enormous volume of heavy, inky vapour, coiling and pouring upward in a huge and ebony cumulus cloud, a gaseous hill that sank and spread itself slowly over the surrounding country. And the touch of that vapour, the inhaling of its pungent wisps, was death to all that breathes.
It was heavy, this vapour, heavier than the densest smoke, so that, after the first tumultuous uprush and outflow of its impact, it sank down through the air and poured over the ground in a manner rather liquid than gaseous, abandoning the hills, and streaming into the valleys and ditches and water-courses even as I have heard the carbonic-acid gas that pours from volcanic clefts is wont to do. And where it came upon water some chemical action occurred, and the surface would be instantly covered with a powdery scum that sank slowly and made way for more. The scum was absolutely insoluble, and it is a strange thing, seeing the instant effect 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
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