Hydrostatics and pneumatics / [Dionysius Lardner].

  • Dionysius Lardner
Date:
1831
Catalogue details

Licence: Public Domain Mark

Credit: Hydrostatics and pneumatics / [Dionysius Lardner]. Source: Wellcome Collection.

    352/376 (page 336)
    solid possesses sufficient strength to enable a globe, or any other vessel formed of it, to resist the atmospheric pressure from without, when that pressure is not ba- lanced by a corresponding pressure from within, unless Fig. 46. it he made of so great a thickness that its weight will very much exceed the weight of the air which it dis- places. To give sufficient buoyancy to a large hollow body, and at the same time to secure it from the effect of atmo- spheric pressure, it will be therefore necessary to fill it with some elastic fluid, which will, by its elasticity, balance the effect of the external air, and, by its small specific weight, produce a degree of buoyancy sufficient to raise the materials of which it is constructed. In this case, as the forces which- act on the balloon are held in a state of equilibrium, or nearly so, no extraordinary degree of strength is required, and any extremely light and flexible substance impervious to air or gas may be used.