Chapter LIIII
Reading edition
ANOTHER METHOD OF SUSTAINING A BALLOON OVER WATER, WITHOUT LOSS OF GASS, OR OF BALLAST.
Section 295. Let the Ballast consist of that Kind of Rope (wound on a Reel) that is either by Nature or Art, specifically lighter than fresh Water: as a hollow cylindrical Rope of Silk, in which Corks are thrust: the Silk to be dipped into elastic Varnish, to prevent the Absorption of Water into the Pores: or a common Rope well varnished; or covered over with a cylindric Case of varnished Silk, might answer the same Intention, if Corks or Bladders were tyed at proper Distances: in which Case, the Rope might, at the first Ascent of the Balloon, hang from the Center above the Car, at its full Extent, suppose a Mile or a Mile and half in Length, without the Encumbrance of a Reel.
If Bladders are used; those that hang near the Car shoud not be more than half blown.
By the above Expedient; as soon as the Balloon began to decline, from Evaporation of Gass, or Depression of the Atmosphere, and the lowest Part of the Rope touched the Water; the Balloon woud continue to levitate, in Proportion to the Quantity of Rope sustained on the Surface of the Water.
The Aironaut woud move less swift indeed, but more conveniently; as he woud not be obliged to rise above the Wind: but be able to lower, and raise himself at Pleasure: first, by pulling up a Part of the Rope into the Car; and having there made it fast;
Secondly, by cutting away, as he saw Occasion, the loose End, and Folds of the Rope so drawn into the Car with him.
