Submarine Appliances And Their Uses
Deep Sea Diving, &c., &c.

“ Kotting- ham." in fhA The. Photographs on the preceding page give a good idea of one of the methods employed e raising of sunken vessels. The s.s. Kottingham had gone down in the fairway of the e Tyue’ and the E”‘ Coast Salvage Company, of Leith, called in to remove the serious obstruction to navigation. A WOODEN COFFER-DAM was built and attached to the sides of the vessel, the hull being- meanwhile made watertight, and the Centrifugal Pumping Engines were set to work to pump out the water enclosed within the walls of the coffer-dam and the hull of the ship. By these means the ship was raised, and after being drawn in towards the bank she was beached at Jarrow. The larger photograph shows the pumping operations, the volume of water delivered by the Pumps being amply demonstrated. The two smaller photographs are VieT ° J u Ve3S befOre and after raisin^ and show the way in which Ae coffer-dam was used and the extent of the structure. Thames Conser- vancy Lifting Lighters. Ipnt T LZfING LI^HTERS used by the River Thames Conservancy Board have done excel- lent work. These lighters are built on a system of construction ordinary dredgers, having an arrangement of watertight compartments length and breadth of the vessels. the vessels. similar to that applied to 3 running the whole A well, or open space, is provided through the centre of the lighter, 6oft. long- 2ft in breadth at the bottom, and ift. 6m. at the top. At the top ends of the well, stiff athwart-ship hi k leads are placed making the foremost and after compartments perfectly watertight. The sides of the well are plated m similar manner to the ordinary side plating and six watertight compartments are formed on each side of the well before 'the fore and after bulk- Russian Ironclad “ Vladi- mir.” ° er arrangements are made to ensure great strength in construction, with the result hat ample longitudinal and vertical rigidity is provided to withstand very heavy lifting strains leaving at the same time sufficient surplus buoyancy to lift 400 tons with each lighter. Colonel Gowan, who cleared the harbour of Sebastopol of the wrecks which had pur- posely been sunk by the Russians during the Crimean War, successfully raised the Vladimir a large ship which, being filled with mud, weighed about 5,000 tons. For this operation he constructed four large PONTOONS or CAISSONS, each about IOoft. long, 65ft. wide, and 22ft. deep. ea-cli end of the pontoons weie fixed two wheels on iron pedestals, over which lifting- chains passed. The pontoons being constructed in watertight compartments, water was let into the after compartment to counterpoise the lifting weight. On each pontoon was fixed a portable steam-engine of 15 horse-power, to work the powerful centrifugal pumps and the winches, the pthbinS Wer1 °ftK21T b1est,q^ahty 11'on- Some difficulty was experienced at first in passing these chains under the keel of the wreck, but by means of a scraper, which was pulled back- wards and forwards a passage, or channel, was made, through which was passed a light chain 0 w ich a heavier chain was attached, and which was brought into position by these means.*’ S.S. “ Prince Consort, H.M.S. “ Part- ridge,” etc. Many other means of raising vessels have been adopted with success. Where the vessel is very small, it may be filled with empty watertight casks, which will be almost sufficient of them- selves to raise it in many cases. Air bags or indiarubber pontoons have been successfully used in many instances, both when introduced into the hold or when attached to the sides of -i wreck 1 he Prince Consort paddle-steamer, of 607 tons gross register, y years ago at Aberdeen, the deadweight lift being about 560 tons. Ly??cSer,meanS may be mentioned the brig Ridesdale, 170 tons’, sunk off rl.M.S. 1 artridge, of 180 tons; and the brig Dauntless, of 17g tons. was in this way raised some Of smaller vessels raised Calshot Castle ; S.S. “ Wolf.” Passing to accounts of the methods by which some notable lifts have of the earliest cases of the raising of an iron ship was that of the Woll a 243ft. long, by 27ft. beam, and 13ft. 8in. in depth. been made, one paddle-steamer, * For description of another plan, see page 130. — c