In the same year the Rattier, the first screw vessel built for the navy, was laid down at Sheerness.

Although of only 888 tons burthen, she was not launched until the spring of 1843.

She was then fitted with the same kind of screw as the Archimedes, that is, a double-headed screw of half a convolution.

Experiments went on for about three years, so as to determine the best proportions of the screw, and the proportions then ascertained have since been the principal guides of engineering practice.
The Rattler was at length tried in a water tournament with the paddle-steamer Alecto, and signally defeated her.

Francis Pettit Smith, like Gulliver, may be said to have dragged the whole British fleet after him.