As far back as the period of the Napoleonic wars, the balloon was given a place in warfare, but up to the Franco-Prussian War of 1870–71 its use was intermittent. The Federal forces made use of balloons to a small extent in the American Civil War; they came to great prominence in the siege of Paris, carrying out upwards of three million letters and sundry carrier pigeons which took back messages into the besieged city. Meanwhile, as captive balloons, the German and other armies used them for observation and the direction of artillery fire. In this work the ordinary spherical balloon was at a grave disadvantage; if a gust of wind struck it, the balloon was blown downward and down wind, generally twirling in the air and upsetting any calculations and estimates that might be made by the observers, while in a wind of 25 miles an hour it could not rise at all. The rotatory movement caused by wind was stopped by an experimenter in the Russo-Japanese war, who fixed to the captive observation balloons a fin which acted as a rudder. This did not stop the balloon from being blown downward and away from its mooring station, but this tendency was overcome by a modification designed in Germany by the Parseval-Siegsfield Company, which originated what has since become familiar as the ‘Sausage’ or377 kite balloon. This is so arranged that the forward end is tilted up into the wind, and the underside of the gas bag, acting as a plane, gives the balloon a lifting tendency in a wind, thus counteracting the tendency of the wind to blow it downward and away from its mooring station. Smaller bags are fitted at the lower and rear end of the balloon with openings that face into the wind; these are thus kept inflated, and they serve the purpose of a rudder, keeping the kite balloon steady in the air.

An early type of the Parseval-Siegsfeld observation balloon.

Used by the Germans in Russia.
An observation balloon about to ascend to watch enemy movements, near Metz, 25th January, 1918.

Various types of kite balloon have been introduced; the original German Parseval-Siegsfield had a single air bag at the stern end, which was modified to two, three, or more lobes in later varieties, while an American experimental design attempted to do away with the attached lobes altogether by stringing out a series of small air bags, kite fashion, in rear of the main envelope. At the beginning of the War, Germany alone had kite balloons, for the authorities of the Allied armies considered that the bulk of such a vessel rendered it too conspicuous a mark to permit of its being serviceable. The Belgian arm alone possessed two which, on being put into service, were found extremely useful. The French followed by constructing kite balloons at Chalais Meudon, and then, after some months of hostilities and with the example of the Royal Naval Air Service to encourage them, the British military authorities finally took up the construction and use of kite balloons for artillery-spotting and general observation purposes. Although many were brought down by gun-fire, their uses far outweighed their disadvantages, and toward the end of the War, hardly a mile of front was without its ‘Sausage.’

For naval work, kite balloon............