Ferris, Richard. [from old catalog] · New York, T. Nelson and sons · leaf 261
a balloon must thereforeweigh less than this, bulk for bulk, in order to becrowded upward by the heavier air—and thus exertits lifting power, as it is commonly called. In practice, two gases have been used for inflatingballoons—hydrogen, and illuminating gas, made or-dinarily from coal, and called… … / One of the otirliost :it(onips to steer Ji sph(M-ie:il bnllooii by retarding itssp(H>fl with thr (lrao;-r()pe, and adjusting (he sail to (he passing wind. BALLOONS. 261 and it Avill therefore be pushed upward in air bythe difference in weight, or 0.0751 lbs. per cubic foot.A cubic foot of coal…
Aeronautics
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
