oubtedly be disastrous to air-ship and crew. For
this reason the non-rigid balloon does not appear to have much future
value as a fighting ship. But, as great speed can be obtained from
it, it seems especially suited for short overland voyages, either for
sporting or commercial purposes. One of its greatest advantages is that
it can be easily deflated, and can be packed away into a very small
compass.

A good type of the non-rigid air-ship is that built by Major Von
Parseval, which is named after its inventor. The Parseval has been
described as "a marvel of modern aeronautical construction", and also as
"one of the most perfect expressions of modern aeronautics, not only on
account of its design, but owing to its striking efficiency."

The balloon has the elongated form, rounded or pointed at one end, or
both ends, which is common to most air-ships. The envelope is composed
of a rubber-texture fabric, and externally it is painted yellow, so that
the chemical properties of the sun's rays may not injure the rubber.
There are two smaller interior balloons, or COMPENSATORS, into which can
be pumped air by means of a mechanically-driven fan or ventilator, to
make up for contraction of the gas when descending or meeting a cooler
atmosphere. The compensators occupy about one-quarter of the whole
volume.

To secure the necessary inclination of the balloon while in flight, air
can be transferred from one of the compensators, say at the fore end of
the ship, into the ballonet in the aft part. Suppose it is desired to
incline the bow of the craft upward, then the ventilating fan would
DEFLATE the fore ballonet and INFLATE the aft one, so that the latter,
becoming heavier, would lower the stern and raise the bow of the vessel.

Along each side of the envelope are seen strips to which the car
suspension-cords are attached. To prevent these cords being jerked
asunder, by the rolling or pitching of the vessel, horizontal fins, each
172 square feet in area, are provided at each side of the rear end of
the balloon. In the past several serious accidents have been caused by
the violent pitching of the balloon when caught in a gale, and so severe
have been the stresses on the suspension cords that great damage has
been done to the envelope, and the aeronauts have been fortunate if they
have been able to make a safe descent.

The propeller and engine are carried by the car, which is slung well
below the balloon, and by an ingenious con