Racing The ordinary rules of the road at sea appl% in the main to yacht-racing. Yachts sailing with the wind free must clear !hose sailing close-hauled. Yachts on the port tack must give way to those on the starboard tack, and an overtaking yacht must clear the vessel, The start in a yacht race is now always a flying one, hut prior to about 1860 yachts started from anchor Frequently much depends upon the start, and accordingly ma noeuvring for initial position is of considerable importance. At the start, as throughout the race, the skipper counts for a good deal. The course to be traversed is marked out by buoys, light-ships or flag-boats. The time allowances corresponding to differences in rating are deter mined in accordance with a scale prepared by the Yacht Racing Association. Vessels always start together, the time allowance being made at the end of the race. Handicapping is also practised to some extent in yacht-racing. Pleas ure yachts are supposed to carry ensigns when in commission, also a hurgee (swallow-tailed pennant) and a private signal flag. Sailing yachts fly the ensign at the main peak; power yachts hang it on a staff at the stern. All yachts when at anchor in the daytime are ex pected to fly an ensign from a stair at the stern. Yachts in commission usually hoist their colors at 8 a.m. and lower them at sunset. Amateur yachtsmen sailing on the coasts and Great Lakes may obtain from the Bureau of Lighthouses at Washington a 'List of Lights and Fog Sig nals` and a •List of Buoys, Beacons and Day Marks,' together with maps, which are very important in navigating.
Racing Yachts.— The designing and con struction of a racing yacht require no small amount of scientific and technical knowledge besides large experience, and consequently the yachts entered for the leading races, at least in the higher classes, are the work of a very few designers and builders. In a yacht intended for racing, speed is the primary essential, and to it accommodation and convenience arc in large measure sacrificed. Moreover, a designer has to take into account the circumstances under which his vessel is to be run or the competitors which she has to meet, because a yacht that does well in fine weather and a smooth sea will usually be of little account in boisterous weather and a rough sea. The rating rules of the Yacht Racing Association (formed in 1875) also con dition the designer's work, and it will he neces sary, therefore, to give some account of them here. The object of rating regulations is to secure that all competitors shall start on prac tically even terms in any given race, and this is achieved by the classification of yachts in well defined groups according to certain measure ments, and also, especially among largeyachts, by means of time allowances corresponding to differences in these measurements. In the early days of racing, yachts were grouped according to tonnage, the tonnage being determined, as for other vessels at that time, by multiplying the length by the breadth and the depth and divid ing by % (afterward 941. This was replaced by what is called builder's measurement or old meas urement, which is still in use for some purposes connected with yachts. The formula for tonnage where 1. and B denote length and breadth re spectisely. The Thames measurement rule, introduced in 1854, made tonnage equal to (L—B)XBXiB but in 1881 the Yacht94 Racing Association introduced the 1730 rule, ac cording to which the tonnage was equal to (LX B)' X B . These rules were found to 1730 have the effect of encouraging the construction of yachts of very narrow beam, especially after about 1871, when designers learned the use of outside ballast on the keel. A great change was effected in 1886 when the length-and-sail-area rule came into {one, and yachts were classified according to rating determined by the formula Length X Sail Area in sq. ft. . The present lin 6000 ear rating rule was adopted in 1896, hut it can not be said that finality has yet been reached. Linear rating is expressed in feet and is deter mined by the formula Length X .75 Girth X .5 s/Sail Area 2 In 1903 the rule was altered to Rating — L X x/3 18 where L = load water line; S sail arca; D= displacement in cubic feet. Limi
tations are added to prevent excessive listed length.
For the smaller vessels wood is the cheapest and lightest material, but larger ones arc made of steel or of steel frames with a wooden skin, the latter class being called composite. Other metals, notably aluminum, have also been used for the construction of yachts. Practically all large composite vessels and also many small ones have a copper sheathing to protect the submerged parts of the wood from the action of the water. The sails of racing yachts are gen erally made of cotton, mostly of the finest Egp tian variety; but ramie fibre is coming into use for this and a mixed cotton and ramie material is also in use. Up till a comparatively recent date flax was generally used for the sails of racing yachts, though it does not produce a sufficiently smooth and close-textured cloth.
The speed of a racing yacht of given size may be regarded as the result of a compromise between stability, which determines sail-carrying power, and resistance-. The sta bility depends upon well-known hydrodynamic principles, and may be roughly said to he deter mined by breadth of beam, the lowness of the centre of gravity of the vessel and the quantity and position of the ballast. Resistance at low speeds is due chietly to surface or skin friction, but at higher speeds it is principally caused by wave-making, a phenomenon too intricate to be discussed here. An increase in beam increases stability, but at the same time increases skin fnction. Wave resistance is less in vessels whose displacement is obtained mainly by breadth than in those where displacement is ilicipalh determined by depth Various means los% ering the cciltre of gravity have been 0,1opti d ss ith athatitave. such as the use of hollow masts and booms, the use of a/uminum for the upper part of the vessel's sides, sic Stone ballast was used in the early days of yachting, but it was superseded by iron, and that in turn by lead. The lead ballast was after ward carried on the keel, and later the keel consisted of a plate of lead, hung horizontally below the hull. The fin-keel followed, this being a fin or extension of thin metal for carrying a lead keel to a lower position. The .4merita was a keel boat, and beat out the English boats because it had a deeper draft. and because the weight of the keel was so cen tred as to bring the effort of the sails well aft When other designers had profited by this idea, and further improvements were demanded, the centre-board was introduced. Many claim this to he an English invention, although it was developed to success by American designers. The centre-board is nothing more than an ad justable keel that may be raised or lowered as conditions make it best. When set low the boat can be steered much closer to the wind. The centre-board boat is very fast in smooth water and down wind. It was used on the Maine in 1870, the Columbia 1871 and on down to the Vigilant in 1893. American yacht builders then returned to keel designs, depending on other proportions. The Defender, Columbia and Re liance were all keel boats. Probably the Madge. of Scotch design, built in 18431, influenced de signs more than any other except the centre board. Her ballast was in one piece of lead. she was full amidships, with heavy displace ment but a very light hull; though cramped in beam she was practically non-capsizable In 1885 Sir Richard Sutton, observing the success of the Madge, built the Genesta on these lines and challenged. Burgess designed the ['wizen on a somewhat similar model, hut wider and shallower than Genesta, and won. In 1891 the agreed waterline length for cup-racers was 46 feet, and Herreshoff designed the Glornana co new principles, giving her an overhang of scene 25 feet, so that she was 71.9 over all. When the Gloriana heeled over she gained in stater line, and the more she leaned the more she gained. As a result, in a stiff breeze she had all the best of it and won easily. This boat was also Herreshoff's first cup-racer with a fin keel. This design was later penalized and nothing radically new in type has developed since.