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Show caFteepa ' good ship down Half of Torpedoed Craft of Great Britain Have Been Salvaged. METHODS GREATLY JMPROVED Much Greater Weights Than Believed Possible Are Now Being Lifted No Hope of Ever Raising Lusitania. London. Of 400 British ships sunk In the last two and a half years at least 50 per cent have been raised from the bottom of the sea. The organization or-ganization responsible the Admiralty Salvage department is composed entirely en-tirely of experts employed by a commercial com-mercial firm which engaged in the business busi-ness before the war. Ships were so cheap then, however, that often It did not "pay to raise a sunken wreck and restore her to seagoing condition. Things are very different now, and the result is that Invention has been stimulated to an extraordinary extent It used to be considered that 1,500 tons was the greatest weight that could, be lifted from under water by wire ropes. A sunken government collier col-lier that was obstructing a fairway was lifted out of the mud recently and carried away by four lifting ships, with sixteen 9-lnch wire ropes, and the deadweight carried was calculated at 2,750 tons. The wreck was shifted one mile at the first lift, and so was gradually taken to the beach, patched up and sent off to the repairing yard. She went back into service and made several voyages before a. torpedo ended end-ed her career altogether. Cannot Raise Lusitania. Ships sunk In deep water cannot be salved. It Is not expected that the Lusitania, for example, will ever be lifted. Divers cannot work In more than 25 fathoms successfully, though for special 'purposes they may sometimes some-times go down to 35 fathoms for a brief spell of work. The hulk of the ships saved have been sunk In less than 20 fathoms, or have been towed Inshore by rescue tugs, and have gone aground In fairly easy positions. The salvage men face considerable risks, not only from bad weather but also from submarine attack. Only one I : salvage ship, however, has been lost through enemy action. One of the largest oil tank steamships steam-ships was mined and caught fire. There was a heavy explosion and tha decks were flooded with burning oil. The cargo consisted largely of benzine. Most persons would conclude that the case was hopeless. Not so. The vessel ves-sel was scuttled by gun fire and thus the fire was extinguished. Then divers plugged all the shot holes, besides closing clos-ing other apertures. On being pumped pump-ed out the vessel floated and was forthwith taken to a repairing port New Pump Is Valuable. , As showing how valuable is the new submersible electric motor pump, a recently torpedoed ship which carried a cargo (mainly foodstuffs) of more than $15,000,000 value had a hole 40 feet long by 28 feet deep in her side. She was taken in tow by rescue tugs, but went down before time had served to beach her suitably. No ordinary pumping power would have served the need, but the new type pump enabled stokehold, engine room and all her after af-ter holds to be pumped out, so that caqpo could be discharged and the vessel ves-sel taken higher up the beach. Then the lightening process was continued until the vessel was floated and taken Into dock, practically all her cargo being be-ing saved. The number of the ships of the mercantile mer-cantile marine actually salved by the department In two years from 1915 to 1917 was 260. All these vessels were of big tonnage. For the present year the monthly totals of such vessels salved were: January, 14; February, 41 ; March, 87 ; April, 38, and May, 19. Thus the department has saved 407 Important vessels of the mercantile marine. This does not Include vessels salved outside of home waters. The larger figures of the latter period pe-riod were due, not to increased enemy activity but to improved salvage methods. meth-ods. Many risks are run by the divers, i particularly from gases generated by decomposed vegetables and meat In the holds of sunken ships, deaths having hav-ing resulted from this cause. Grain, it seems, develops sulphuretted hydrogen, hydro-gen, which occasions blindness and violent sickness. A chemist, however, has found a preparatibn which when sprayed on a rotting cargo Immediately kills the gases and enables men to carry on their work in safety. |