SEA SALVAGERS.

Timaru Herald, Volume CXXXIV, Issue 18822, 10 March 1931, Page 12

SEA SALVAGERS.

MODERN METHODS. RISKS SALVAGERS RUN. The loss of tne salvage steamer Artlglio off the west coast of France while on a salvaging job is a reminder of the risks that sea salvagers run, though there has never been another example of a ship being overwhelmed and destroyed by a mountain of water caused by a terrific explosion (says a writer in the Melbourne “Herald”). The disaster is unique in that respect. The Artiglio was a most interesting and valuable vessel, representing the new type of salvage ship as compared with the old. The art of sea salvage has advanced enormously since the war, and feats which had hitherto been regarded as impossible have been frequently accomplished. The modern salvage ship, specially built and equipped for the work, is really a floating workshop fitted with most modern contrivances. Salvage Is essentially work where human skill, experience, and determination are pitted against wind and sea. Formerly wrecks sunk at a great depth were regarded as unsalvagable, but a new and great advance has been made in diving, the old-time helmet and dress being superseded for deep work by the new diving chamber. There are various methods of raising wrecks. One is by sinking pontoons and then filling them with compressed air so that they float the wreck to the surface; another is by filling compartments in the wreck with compressed air; a third is by installing powerful pumps and giving the wreck sufficient buoyancy, and there is also the difficult case of uprighting the capsized vessel lying on its side. The modern salvage ship is small, but complete, and usually built of wood. Modern pumps are capable of discharging 5000 tons of water in an hour; instead of working in darkness, the diver is equipped with electric light conveyed through watertight cables; and in recent years a complete group of working plant for under sea operation has been evolved. This includes submersible oxy-aceytlene plant for cutting steel plates under water, submersible pneumatic hammers and drills and electrically driven submersible pumps, which are lowered into the water from a derrick and can pump water to a height of 80ft.

It is scarcely an exaggeration to say that nowadays salvagers and salvaging plant are so advanced that no job is considered hopeless unless at a great depth. It is, for example, quite impossible to salvage or even to reach the Titanic, which lies at ocean depth. The diver can work at 200 or even 250 fathoms for a brief spell, but he cannot descend to 2000 fathoms. Fortunately, all around the oceans is the comparatively shallow continental shelf, and wrecks lying in water up to 60 or 70 fathoms can be reachel and searched even if they cannot be raised. But the two jobs are entirely different, and require different plant and treatment. Thus to search for the bullion room of a sunken liner and to extract therefrom the gold and send it to the surface is an entirely different job from that being carried on at Scapa Flow, where ships of the German Fleet are being raised and righted in shallow water.

The diver’s main bugbear is a strong current or tide, which sweeps him off his feet and also makes the task of those on the salvage ship difficult. Darkness has been overcome by strong electric lights, but wind and weather still remain the dominant factors. For work of this kind the weather must be “set fair”; the slightest “joggle” on the sea complicates matters, and adds to the risk, and consequently most of the big salvage jobs in European waters are carried out in the summer. The Artiglio was working in December, but it is believed that she was at work on the wreck of the Florence inside the sheltered channel off Quiberon.