Like the brothers Tissandier, they used an electric battery and motor to drive their screw, their motive power being 9 h.p. It was claimed that out of seven journeys, the airship returned five times to the place whence it started. As an example of these journeys, on September 22nd, 1885, a journey was made from Meudon to Paris and back again. On this day the wind was blowing at a velocity of about 3.50 metres a second--what we should call a calm. Few, perhaps, who saw the small naval airship, the “Beta,” manœuvring over London this autumn realised that a navigable balloon, not so very much unlike it in form, was speeding its way over Paris as long ago as 1885. The advent of the first at all practical military airship was forgotten because the experiments, comparatively successful as they were, suddenly ceased. They came to an end because it was found that though electricity as a motive power could afford an airship demonstration, it was unfitted for serious and prolonged use. One industry has often to wait for another--the world had to wait for the missing link in aërial navigation. That was the light petroleum motor. With its coming came the era of airships and aëroplanes. CHAPTER III TYPES OF MODERN AIRSHIPS With the new century came the modern military airship--to stay, at any rate, until the heavier-than-air principle of aërial navigation has so developed as to absorb those features of utility the airship has and the aëroplane has not. During the fourteen years which have seen the construction of practical airships, three distinct types have been evolved--(i.) rigid, (ii.) non-rigid, (iii.) semi-rigid. In considering the airships of Great Britain, France, and Germany, I propose to class them together as to types rather than under nationalities. Each type has its own peculiar advantages. The choice of type must depend upon the circumstances under which it is proposed to be employed. [Illustration: Top: SNAPSHOT OF ZEPPELIN IN MID-AIR. Centre: MILITARY LEBAUDY AIRSHIP, showing fixed vertical and horizontal fins at the rear of gas-bag, vertical rudder, and car suspended from rigid steel floor underneath gas-bag. Bottom: CAR OF A LEBAUDY AIRSHIP, showing one of the propellers.] I. RIGID TYPE.