Baron Scott's design for an aerostat, 1789.
© Science Museum / Science & Society Picture Library
In 1789 Baron Scott, a French army officer, published a work entitled 'aerostat dirigeable a volonte' which contained these illustrations of a steerable, lighter-than-air craft. The vesel he envisioned was like a fish-shaped balloon and supported French engineer and airship pioneer, Meusnier's (1754-1793) proposal that, like a ship on water, an airship should have a definite bow and stern and be longer than it was wide. The most original feature of Scott's design was the introduction of two 'ballonets', or air pockets, at either end which could be inflated or deflated to increase the buoyancy at opposite ends of the balloon. Scott thought this feature would enable the ballonets to achieve an incline for ascent or descent which would increase the forward motion. Dimensions: 146mm x 216mm.