ABSTRACT
The aeroplane and the dirigible are no sudden advances in man’s struggle with nature, but rather the final yielding of defences which have withstood his attacks for a hundred years. In 1852 Giffard, the inventor of the injector which bears his name constructed a balloon fitted with a steam-engine and propeller, and succeeded in driving it at the rate of 5 or 6 miles an hour. An interesting balloon was constructed in 1872. The engine was driven by gas obtained from the balloon itself, and air was pumped into a smaller bag called a ballonnet contained inside the larger one, in order to compensate for the gas consumed. The French Army used a balloon in the Franco-German War in which the screw was worked by eight men, and at a later date one was constructed with an electric motor driven by a battery.
