Centre-Board Boats

In 1870 a boat was built by Messenger, and called Wideawake, with a kind of shoe keel. The boat or rather canoe was 15ft. 10in. long, and 3ft. 2in. beam, depth, gunwale to keel, 1 ft. 4in. She had an oak keel increasing in depth from tin. forward, to 6in. aft. To this keel was fitted a hollow galvanised keel—a kind of case in fact to take the oak keel 12ft. long, made of fin. iron (see Fig. 61). The keel was pivoted forward 4ft. from the stem plumb to load line. Care was taken to make the iron case fit the oak keel. The case was raised by a wire fastened to the stern end of the case, and passing through a tube as shown by A B, Fig. 62. The wire passed over a pulley on deck and was secured at mainmast. The keel weighed 281b.

A

better plan than the shoe keel was fitted a few years ago in a small boat, Robin Hood, by Searle, for Mr. W. B. Forwood. She had an oak keel 5in. deep, in the under side of which a slot 9ft. long and 3in. deep was cut; into this slot a galvanised iron plate fin. thick, 9ft. long, and 3in. deep was fitted. It was raised and lowered by a rod at each end, working in upright lead pipes.

Among the many curious contrivances to prevent leeway, one exhibited at the Exhibition of 1851 is as strange as any. The designer's idea appears to have been, that to obtain the greatest advantage in the way of stability a yacht should be very broad and big above water, and very narrow and small under it (see Fig. 63) ; and that to get a large amount of lateral

resistance, two keels should be had instead of one shaped longitudinally as shown by Fig. 64.

So far as the question of stability is concerned, we need scarcely say more than that it would be much increased if the greatest beam were put on the water line ; but as the idea of parallel keels is continually cropping up, it may be well to point out that they cannot be of any advantage. In the first place, there is an extra surface for friction provided by the doubling of the keels, and as surface friction enters so largely into the aggregate resistance of a vessel double keels should be condemned for this reason alone. Secondly, the actual increase in the lateral resistance would be only a very small percentage of the added surface, as the water would practically be locked up between the two keels, and so really out of the four sides of the keels, only one side (the leeward one of the leeward keel) would meet with lateral resistance.

Among many other contrivances, the time-honoured lee-board may be mentioned, and the " horizontal keel," descriptions of both of which will be found at the end of the book.