The works of Edgar Allan Poe; newly collected and edited, with a memoir, critical introductions, and notes, by Edmund Clarence Stedman and George Edward Woodberry; the illustrations by Albert Edward Sterner.

THE BALLOON HOAX

ellipsoid. Its length was thirteen feet six inchesheight, six feet eight inches. It contained about
three hundred and twenty cubic feet of gas, which,
if pure hydrogen, would support twenty-one pounds
upon its first inflation, before the gas has time to
deteriorate or escape. The weight of the whole machine and apparatus was seventeen pounds -leaving
about four pounds to spare. Beneath the centre of
the balloon, was a frame of light wood, about nine
feet long, and rigged on to the balloon itself with a
network in the customary manner. From this framework was suspended a wicker basket or car.
The screw consists of an axis of hollow brass tube,
eighteen inches in length, through which, upon a
semi-spiral inclined at fifteen degrees, pass a series
of steel wire radii, two feet long, and thus projecting
a foot on either side. These radii are connected at
the outer extremities by two bands of flattened wire
— the whole in this manner forming the framework
of the screw, which is completed by a covering of
oiled silk cut into gores, and tightened so as to present a tolerably uniform surface. At each end of its
axis this screw is supported by pillars of hollow brass
tube descending from the hoop. In the lower ends
of these tubes are holes in which the pivots of the
axis revolve. From the end of the axis which is
next the car proceeds a shaft of steel, connecting the
screw with the pinion of a piece of spring machinery
fixed in the car. By the operation of this spring the
screw is made to revolve with great rapidity, communicating a progressive motion to the whole. By
means of the rudder the machine was readily turned
in any direction. The spring was of great power,
compared with its dimensions, being capable of raising
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