A Short History of Balloons and Flying Machines #250491

The flaccid bag was suspended on a pole 33 ft. High, and straw and chopped wool were burnt under the Opening at the bottom: the vapour soon inflated the bag, and on a sudden this immense mass ascended into the air with such velocity that in less than ten minutes it appeared to be about toises above the heads of the spectators, then the vapour escaping through some Ioopholes the great globe gradually descended with little damage to it. II. — The Parisian philosophers resolved to use, instead of vapour, inflammable air. This being expensive, the author of the book now quoted set on foot a subscription and raised a sum sufficient to set to work, and they constructed a globe of taffetas glazed over with elastic gum, this was filled with inflammable air, produced from lbs. Of iron filings and 498 lbs. Of vitriolic acid.