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Boat Sailing for Amateurs.
In the following chapters it is proposed to begin at the beginning with the principles of sailing, and to treat of the practice of it from the management of open one-sailed boats up to a ten-ton yacht. By the time when the amateur can sail his five or ten-ton yacht he will not be content with elementary treatises. We shall assume that our readers are either quite ignorant of the art we hope to teach, or that they have only attained the usual first stage of knowing just sufficient to see how much there is that they do not know.
Boat sailing is a most fascinating pursuit, and when a man has once taken to it he is, if circumstances permit, a sailor to the end of his days. There is one caution we should like to give at the very outset.
Learn to swim before you go sailing. No mere pleasure is worth risking one's life for, and accidents will happen even to the most skilful sailorman. Many a life has been lost for the lack of ability to swim a hundred yards, or to support a lady or comrade for
a few minutes in the water. Ladies and young people are so frequently taken out in sailing boats that their safety should be especially considered, and a man who can swim, and has taken the wise precaution to keep a life-belt on board, is the only skipper a lady should cruise with. Learn to swim, therefore, is the first axiom of boat sailing. The second is, Be careful. Young fellows think it dashing and manly to be reckless and careless of safety; older sailormen know that it is not only imprudent but unfair to the boat itself, which in the hands of a skilful sailor seems to become a thing of life worthy of care. It
also be taken for granted that a careful and cautious man, so that he be not timid, will get more work out of his boat, and have greater achievements to boast of, than the reckless man. If the tyro will bear these two cautions in mind we shall have the greater pleasure in instructing him.
The first quality of a boat is that it should float on the surface of the water, and there are one or two points about this floating power
which should be understood. A cubic foot of fresh water weighs 62£lb. Any substance of precisely the same weight for bulk would sink in the water until it was covered, but would not go to the bottom unless it was pushed there, when it might remain. If the substance were heavier than the corresponding bulk of water, it would sink with greater or less rapidity. If it were lighter it would float with more or less of it above the surface. The rule to be remembered is this : That any body which, bulk for bulk, is lighter than water, will displace a quantity of water equal to its own weight. The space which it occupies beneath the surface would contain a quantity of water exactly equal to the entire weight of the boat with everything on board. Thus a small boat, weighing exactly
a half a ton, will displace half a ton weight of water; and if a man, weighing, say, 10st., gets on board, 140lb. of water will be displaced by the additional weight; and a proportionate amount of resistance to the passage of the boat experienced. It does not follow that such increased resistance is prejudicial, as additional weight gives greater stability and sail carrying power, of which we shall treat presently. Generally speaking, greater weight has the advantage of giving greater sail carrying power, which more than counterbalances the extra resistance ; but the calculations which may be entered into on this point alone would fill a volume, and must be passed over here.
The wind has two main effects upon the sails of a vessel, the propelling and the heeling. While the first has to be encouraged, the last has to be resisted. The resistance of a vessel to the heeling or upsetting power of the wind is effected by stability. Of this stability there are two kinds—that which arises from the form of the vessel alone, and that arising from the addition of weight. As an instance of the first or primary stability,
FIG. 1. DEEP YACHT UNBALLASTED. place à flat bottomed box on the table, with a mast in it, to act as an upsetting lever. By its side place one of those toy figures, with a round and leaded base, which, however much you may knock them over, regain their uprightness. This is to show the action of the other or secondary stability. Now push the box over by the mast. You will find it takes a good deal of force to cant it over to a sharp angle with the table, but when it reaches that angle it falls over altogether, and will not right itself. Now try the weighted figure. The slightest touch brings it over on its side, but when the pressure is removed it speedily rights itself. We will now transfer this experiment to the water. Fig. 1 is the section of a deep yacht unballasted, and therefore floating on its side. Fig. 2 is the same heavily ballasted, and floating as it should do in sailing trim. Fig. 3 is the section of an ordinary shallow centre-board boat. This has ballast in, but if it had not it would still float upright, and only be a little higher out of the water. In Figs. 4 and 5 both boats are heeled over to the
same angle by the wind. To do this has required much greater wind power in the case of the flatter boat than in the other ; but now mark the difference. Any further
heeling would upset No. 5, FIG. 2. SECTION OF DEEP YACHT the flat boat, but No. 4 could BALLASTED.
only be heeled further by a greatly increased power, and even if it should be thrown flat on the water, it would rise again when the blast was over, or the sheets eased so as to let the wind out of the sails. The practical deduction from this is that a deep-keel yacht
is safer, particularly in a disturbed sea, than a shallow one. Its disadvantages are that, as it has a greater displacement, it will require more sail to drive it
at the same speed through FIG. 3. SECTION OF CENTRE-BOARD Boat. the water, and its greater draught of water will unfit it for use in shallow places. Therefore, as regards the choice between deep-keeled and shallow centre-board yachts, it will depend upon the kind of water where the amusement is likely to be carried on. If shoals are frequent, such as is generally the case in rivers and estuaries, the choice