Mr. Osborne,) at the seat of the latter gentleman near Penstruthal, in Wales. Mr. Henson, accompanied by his friend Mr. Ainsworth, was admitted to a private view of the balloon, on Saturday last—when the two gentlemen made final arrangements to be included in the adventure. We are not informed for what reason the two seamen were also included in the party—but, in the course of a day or two, we shall put our readers in possession of the minutest particulars respecting this extraordinary voyage.
The balloon is composed of silk, varnished with the liquid gum caoutchouc. It is of vast dimensions, containing more than 40,000 cubic feet of gas; but as coal gas was employed in place of the more expensive and inconvenient hydrogen, the supporting power of the machine, when fully inflated, and immediately after inflation, is not more than about 2500 pounds. The coal gas is not only much less costly, but is easily procured and managed.
For its introduction into common use for purposes of aerostation, we are indebted to Mr. Charles Green. Up to his discovery, the process of inflation was not only exceedingly expensive, but uncertain. Two, and even three days, have frequently been wasted in futile attempts to procure a sufficiency of hydrogen to fill a balloon, from which it had great tendency to escape owing to its extreme subtlety, and its affinity for the surrounding atmosphere. In a balloon sufficiently perfect to retain its contents of coal-gas unaltered, in quality or amount, for six months, an equal quantity of hydrogen could not be maintained in equal purity for six weeks.
The supporting power being estimated at 2500 pounds, and the united weights of the party amounting only to about 1200, there was left a surplus of 1300, of which again 1200 was exhausted by ballast, arranged in bags of different sizes, with their respective weights marked upon them—by cordage, barometers, telescopes, barrels containing provision for a fortnight, water-casks, cloaks, carpet-bags, and various other indispensable matters, including a coffee-warmer, contrived for warming coffee by means of slack-lime, so as to dispense altogether with fire, if it should be judged prudent to do so. All these articles, with the exception of the ballast, and a few trifles, were suspended from the hoop over head. The car is much smaller and lighter, in proportion, than the one
