The rule was fair enough at that time, because the bull was osually half as deep as it was wide, and the length of the interior space that could have been conveniently used for storing cargo was about equal to the length of the keel less the breadth of hull. But a way to evade the rule and build a large ship that should show the tonnage of, and be classed with, a small one, had been found before the rule was adopted.
The cutter Cygnet (1816) bad a water-Hoe length of 51 feet, but, because her sternpost raked for ward and her stem aft, her keel was less than 43. The Cygnet method of maiutailling size and re (hieing tonnage bee:tine popular. The rule was therefore changed, and the length of the yacht was measured from stem to sternpost on deck. Since 1878 the length has been pleasured on the water line. But while the length was measured on deck, the designers began to build an exten sion to the hull beyond the sternpost, thus ob taining a long ship that would yet show a small measurement, and that extension, or overhang, is still popular.
Because the rule assumed the depth to be one half the beam, and thus taxed beam twice and left depth untaxed, the designers,. in their efforts to produce large ships that would class with sinall ones, pinched the beam and added to the depth and length. Thus the 5-ton Doris (1885) was 33 feet 8 inches long 00 the water line, 5 feet 7 inches beam. and 7 feet draught; she spread 1116 feet of canvas and her displacement (the true measure of size) was 12.55 tons. Yet she was classed with the Diamond (1873), that was only 25 feet 3 inches On the water line, spread 671 feet of canvas, and displaced 4.92 tons. :Models like that of the Doris, however, wrought an im provement in ballasting. The designers first sub stituted iron ore for the shingle of the old times, and then used lead which they bolted under the keel. As the centre of gravity of the hull was thus lowered it was possible to increase the sail area—a decided step in advance.
In America the racing model came from the small boat, usually a sloop or catboat, formerly called a sandbagger or skimming,-dish. This had great width in proportion to its length, and ex tremely shoal draught. A centreboard (a plank on edge that could be moved up and down through a slot in the keel) gave lateral plane.
When the first challenger for the Imerica's cup—James Ashbury's schooner Cambria—met the fleet of the New York Yacht Club (August 8, 1570), the swiftest of the defenders were yachts developed from the broad and shoal bulls of the sandbagger sloops. The schooner Magic led the
fleet. She was 79 feet long on the water line, 20.5 feet beam, drew 6.25 feet of water, and measured 92.2 tons. The Cambria was 98 feet long on the water line, 21 wide, drew 12 feet of water, and measured 24S tons. Each was a type of its nation, and the race therefore had no direct influence on American racing models. But the race had a tremendous influence on American yachting. As a national sport in America yachting began with these races.
Within ten years after the defeat of the Cam bria there were three series of races for the Amer ica's cup without changing the conditions influ encing the American type of model. Keel yachts were built in America for cruising, and the Vindex, the first American yacht that was laid down without a whittled mode], and the first American iron yacht, was built at Chester, Pa., on lines similar to the British Mosquito. But for racing the skimming-dish model retained its popularity.
In 1881, however, a British cutter of deep and narrow hull was impo•ted—the Madge. She was 46 feet 1 inch long over all, 35 feet 9 inches on the water line, 7 feet 9 inches wide, and S feet 3 inches draught. She had an enormous displace ment in proportion to her sail area, but she won seven races out of eight starts against smart American yachts.
The influence of this yacht was great and last in yachts of similar design were built o• imported. The Genesta and the Galatea, two British cutters of the extreme narrow design, came as challengers for the America's cup (1835 and 1886). They were defeated by the centre board sloops Puritan and Mayflower, but their failure did not immediately injure the popularity of the 'knife-blade' model. In fact, after the fashion of the British model, the Puritan and the Mayflower both carried lead on their keels, and both were of greater depth and displacement than the type American racer of previous years. The Volunteer, that defended the cup when the Thistle came (1837). was still deeper and of greater displacement, while the Defender, built to meet the America's cup challenger Valkyrie III. (1895), was much like the British type of the day.