Page:Encyclopædia Britannica, Ninth Edition, v. 14.djvu/591

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LIFEBOAT 571 about 9 cwts. in a 33-feet boat, and to the air-cases and ballast, which latter weighs from 7 to 8 cwts. When the boat is upset it cannot rest on its two elevated air-chambers; it necessarily rolls on one side, then the heavy iron keel and ballast come into play and drag it back to its right position FIG. 2. Lifeboat (Sheer Plan) FIG. 3. Lifeboat (Deck Plan). in a few seconds. This principle of self-righting was dis covered at all events first exhibited at the end of last century, by the Rev. James Bremner of Orkney, but was not finally adopted till the middle of the present century. The self-emptying quality depends chiefly on the well- known physical fact that water must find its level. The floor of the lifeboat (fig. 2, the dotted double line ex tending from stem to stern), on which the men s feet rest when seated on the thwarts, is placed so as to be very slightly 2 or 3 inches above the level of the sea when the boat is fully manned and loaded. In this floor there are six holes of C inches diameter, into which are fitted six metal tubes. These pass through the boat s bottom into the sea. The water of course enters them, but cannot rise above them into the boat, because it cannot rise above its own level. Valves at the upper ends of the tubes, opening downwards, prevent the annoyance of water spurt ing in, but allow it freely to run out. When, then, a billow overwhelms the boat, and fills it, the water rushes violently down the discharging tubes until it reaches the sea-level ; by that time it has descended below the level of the floor and left the boat empty. So complete and swift is the process that a filled boat frees herself in about half a minute. This principle was first applied by the institution in 1851. Lifeboats devoid of the self- discharging quality become temporarily useless when filled by a sea, as they can be emptied only by the slow and laborious process of baling. Strength, that will enable the lifeboat to suffer treatment which no ordinary boat could stand, is dependent on peculiarity of construction and material. The best Hon duras mahogany is used, and the diagonal plan of construc tion adopted, that is, the boat has two distinct " skins " of planking, both sets of planks being laid on in a position diagonal frj the boat s keel and contrary to each other, besides passing round from gunwale to gunwale under the boat instead of from stem to stern as in ordinary boats. The skins have a layer of prepared canvas between them, and thus great strength and elasticity are combined. The carriage of the lifeboat is an essential adjunct for the purpose of conveying it over any kind of road or beach to the place where it may be required. It can be run deep into a raging surf, and the boat, with its crew seated and oars ready out, can be launched at once, by blocks and tackle, so as to enable the men to dash forward and meet the incoming rollers with sufficient force to propel it through or over the seas, and thus avoid the risk of being hurled back on the beach. Each lifeboat is furnished with a set of spare oars, as these are frequently broken. The institution s lifeboats are of various sizes six, eight, ten, and twelve oared, and they are placed at various points of the coast according to the necessities of each station. Some are called out at long intervals ; others, such as those near the Goodwin Sands, are constantly on duty in rough weather that of Ramsgate having a steamer to attend on it, which lies in harbour, with its fires banked up, ready for instant action night and day. The average cost of a lifeboat station is 1000, the boat and equip ments, including belts and carriage, costing 650, and the boat-house 350. The average annual expense of main taining a station is 70, which is expended in paying the crew for going off and saving or attempting to save life from shipwreck, for exercising the lifeboat once a quarter, paying coxswain s salary, replacing gear, and repairs. The lifebelt of the institution is a part of the equipment of the lifeboat which merits special attention, because it is a very efficient contrivance, and has been the means of saving many lives in time past. Fig. 4 shows its appearance and the manner in which it is worn. It was designed in 1854 by Admiral J. R. Ward, the institution s chief inspector of lifeboats. It is made of cork fastened on canvas, and combines great buoyancy with strength and flexi bility. It not only floats a heavily-clothed man head and shoulders above water, but enables him to support a comrade easily the extra buoyancy being 25 lt>. One of its distinctive features is its division at the waist, by which means great freedom of action is allowed. It serves also as a species of armour to protect the wearer s most vital parts from blows against rock or wreck, while it affords some degree of warmth. No man may serve in the lifeboats of the institution Fig. 4. without it, and it would be well if every British ship were obliged to carry lifebelts of this kind. History. The first lifeboat was conceived and designed by Lionel Lukin, a London coachbuilder, in 1785. Encouraged in his philanthropic plans by the prince of Wales (George IV.), Lukin fitted up a Norway yawl as a lifeboat, took out a patent for it, and wrote a pamphlet descriptive of his " Insubmergible Boat." Buoy ancy he obtained by means of a projecting gunwale of cork and air- chambers inside one of these being at the bow, another at the stern. Stability he secured by a false iron keel. The self-righting and self-emptying principles he seems not to have thought of ; at all events he did not compass them. Despite the patronage of the prince, Lukin went to his grave a neglected and disappointed man. But he was not altogether unsuccessful, for, at the request of the Rev. Dr Shairp, Lukin fitted up a coble as an " unimmergible " lifeboat, which was launched at Barnborough, saved several lives the first year, and afterwards saved many lives and much property. Public apathy in regard to shipwreck was at length swept away by the wreck of the "Adventure" of Newcastle in 1789. Tins vessel was stranded only 300 yards from the shore, and her crew dropped, one by one, into the raging breakers in presence of thousands of spectators, none of whom dared to put off in an ordinary boat to the rescue. An excited meeting among the people of South Shields followed ; a committee was formed, and premiums were offered for the best models of a lifeboat. This called forth many plans, of which those of William Wouldhave, a painter, and Henry Greathead, a boatbuilder, of South Shields, were selected. The committee awarded the prize to the latter, and, adopting the good points of both models, gave the order for the construction of their boat to Greathead. This boat was rendered buoyant by nearly 7 cwts. of cork, and had very raking stem and stern-posts, with great curvature of keel. It did good service in after years, and Greathead was well rewarded; nevertheless no other lifeboat was launched till 1798, when the duke of Northumberland ordered Grcathead to build him a lifeboat which he endowed. This boat also did good service, and its noble owner ordered another in 1800 for Oporto. In the same year Mr Cathcart Dempster ordered one for St Andrews, where, two years later, it saved twelve lives. Thus the value of life boats began to be recognized, and before the end of 1803 Greathead had built no fewer than thirty-one boats eighteen for England, five for Scotland, and eight for foreign lands. That these boats were lamentably insufficient to meet the necessities of England was shown year after year by the ever enlarging record of wreck and loss of life on her shores ; nevertheless, public interest in lifeboats was not thoroughly aroused till 1823. In that year Sir William Hillary, Bart., stood forth to champion the lifeboat cause. Sir William dwelt in the Isle of Man, had