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Swedish builders (in the forefront of
theoretical design) gave arising floor, a full fore body, and a fine
after body, which was the British tendency also. The best clippers had
a moderate rise offloor, an easy round of bilge, and the fore and after
bodies equally balanced.
The fineness of the extremities of the clippers was such that
they could be easily depressed by the addition of little weight. This
was taken advantage of, when loading tea, by moving portable weights in
boxes along the deck to give a slight trim by the stern. It was long
considered that a ship sailed better when trimmed by the stern, and as
during the voyage provisions stowed in the after part and fresh water
in after tanks would be consumed, this loss of weight could be
compensated by the additional weights in the boxes. Tea chests were
sometimes stowed (illegally) in the after accommodation.
The fineness of the underwater body could be carried too far in
the interests of speed, resulting in instability. The famous Leander
was at fault in this respect as she needed so much ballast that a full
cargo of tea could not be stowed before the ship was down to her marks.
The development of the upper stem in the British clippers
closely paralleled the American style, on the wooden and composite
hull. After the planked-in, overhanging, Aberdeen type bow, the
termination of the bow planking was straightened out to meet the side
of the stem in a slightly raking straight line or gentle curve, with
the forecastle deck line considerably fined down to a very light hollow
flare or straight vee'd section.
The long projecting upper stem knees with ornamental side cheeks
and headboards with their supporting timbers were too popular to
eliminate ; a markedly different attitude from that of the Americans,
who considered the British tradition as 'old hat'.
However, these headboards were considerably reduced in size and
weight and frequently made portable so that once at sea they were
unbolted and removed, leaving only a minimum framework. The iron
clippers, however, did retain the skin of the ship carried out to the
curved stem knee until the last days of the sailing ships, and into
modern times in the case of large steam yachts. This style inherited
the name 'clipper stem' which we use today whenever it occurs.
One of the greatest difficulties the clipper ship designers
faced was the lack of continuing, progressive records on which to build
up facts. Naval warship designers could draw on statistics from whole
fleets over many years and effect gradual experimental changes to
arrive at certain facts, whereas the merchant ship designer had only
the ships produced from his own yard on which to prove his theories.
Much of what he did was based on instinct guided by intelligent
observation, after the elementary facts had been established
mathematically.
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