the vessel, and was so satisfied with the performance of the
screw that he recommended his directors to adopt this method for
propelling the Great Britain. His advice was adopted, and the vessel
was altered so as to adapt her for the reception of the screw. The
vessel was found perfectly successful, and on her first voyage to
London she attained the speed of ten knots an hour, though the wind and
balance of tides were against her. A few other merchant ships were
built and fitted with the screw; the Princess Royal at Newcastle in
1840, the Margaret and Senator at Hull, and the Great Northern at
Londonderry, in 1841.

The Lords of the Admiralty made slow progress in adapting the screw for
the Royal Navy. Sir William Symonds, the surveyor and principal
designer of Her Majesty's ships, was opposed to all new projects. He
hated steam power, and was utterly opposed to iron ships. He speaks of
them in his journal as "monstrous."[7] So long as he remained in
office everything was done in a perfunctory way. A small vessel named
the Bee was built at Chatham in 1841, and fitted with both paddles and
the screw for the purposes of experiment. 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. Were the paddle our only means of propulsion, our
whole naval force would be reduced to a nullity. Hostile gunners would
wing a paddle-steamer as effectually as a sportsman wings a bird, and
all the plating in the world would render such a ship a mere helpless
log on the water.

The Admiralty could no longer defer the use of this important
invention. Like all good things, it made its way slowly and by
degrees. The royal naval authorities, who in 1833 backed the side
paddles, have since adopted the screw in most of the ships-of-war. In
all long sea-going voyages, also, the s