NO MORE SEA-SICKNESS.

Oamaru Mail, Volume XXXIX, Issue 10780, 31 May 1911, Page 2

NO MORE SEA-SICKNESS.

SHIPS THAT CANNOT ROLL. Even, the waves of the sea can now be conquered, by modern science. Bad sailors will rejoice to hear that; experts in naval construction have: devised a plan which will minimise, if not . perhaps stop altogether, the rolling of a ship at sea. . Sir Phillip Watts, the Director of Naval Construction sinqe 1901, who" was present at the last day's sitting of the spring meeting of the Naval Archi--' teets, when Dr H. Frahm, a Germanengineer, read a paper on recent experiments with anti-rolling tanks, states that "the idea of anti-rolling tanks,: filled with water, had been carried -out in the. old ironclad Inflexible. The tanks described by Dr Frahm are erected on each side of the vessel, and" are connected by an extremely large pipe or channel, so that the wafer in them can flow from one tank to thp other. Sir Phillip Watts v described : the plan or device as a "ship that carries her own waves" —and those waves in the ' tank counteract, to a great extent, the real waves of the sea. . "A ship at sea," said Sir Phillip, "synchronises in her rolling with the waves. . She does not hurry or delay in .her swine, but moves just as the waves force her to. Her movement is whpt is known as 'co-periodic.' 1 But when a vessel is fitted with anti-rolling tanks,' and' she goes to starboard, some ninety tons of water in her tanks goes over to starboard, too. This weight of water delays her from coming back on the rhythm of the waves, and really acts as a wave working in the opposite direction. Consequently the regular swing of the wave is broken, and the ship, by virtue of her own self-carried waves, is able to resist, at least to a large extent, the power of the waves of the sea.

"The" idea, however, is not new. I myself designed two 'anti-rolling-tpiks' for the old battleship Inflexible in 1883, but, owing to the difficulty of finding room for them, only one was constructed. This tank, owing to want of space, was the same depth right across the ship,- but even then it reduced the rolling by some 25 per cent." "I do not think that these tanks could be fitted with oili fuel, because it is difficult to build tanks which are oil-tight." Herr Frahm, in his lecture on his •anti-rolling tanks, stated that experiments on two large trans-Atlantic passenger steamers, the Ypiranga. and Corcovado, vessels of 14,000 tons loaded displacement, which, though now and of excellent construction, were said to be bad rollers, had been very successful-

Even under the worst conditions the tanks had a very favorable influence, and when, during experiments, they wore temporarily discontinued, the passengers urged to have them put into use again. Anti-rolling tanks would doubtless prove of the greatest importance to men-of-war. A steady gun platform was almost indispensable to the gun-. ner» and he was, he added, about to make experiments on another form of anti-rolling device, which was especially suited to men-of-war. Sir Phillip Watts described the experiments on the old Inflexiblej saying the water-cham-ber acted' satisfactorily. The water, however, made a great noiso. Water, too, added Sir John Thorneycroft, required an appreciable amount of space. It would be an advantage if tliey could use something heavier than water. Of course, if mercury were not so expensive,, the tanks could be got into very small space. If they. were hampered for space, the gyroscope might overcome the difficulty.