NO MORE SEA-SICKNESS.

Taranaki Daily News, Volume LIII, Issue 324, 10 June 1911, Page 10

NO MORE SEA-SICKNESS.

SHIPS THAT CANNOT ROLL. Even the waves of the sea can now hi- conquered by modern,science^ Bad sailors will, rejoice to. that experts in naval construction Jiave ■ vised a plan which will minimise, if not perhaps stop altogether, the rolling of a ship at sea. Sir Philip Watts, the Director of Naval Construction since l'Jtl't, wno was present at the last day's sitting of the spring meeting of tho Naval Architects, when Dr. H. Frahni, a German engineer, read a paper on recent experiments with anti-rolling tanks, states that, the idea of anti-rolling tanks, filled with water, had heen carried out in the old ironclad Inflexible. The tanks described by Dr. Frahm are creeted on each side of the vessel, and are connected by an extremely large pipe or channel, .so that the water in them can flow from one tank to the other. Sir Philip Watts described the plan or device as a "ship tnat 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 Philip, "synchronises in her rolling with the waves. She does not hurry or delay in her swing, but moves just as the waves force her to. Her movement is what is known as 'co-periodic.' But when a vessel is fitted with anti-rolling tanks, and she goes to the 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 rythm 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 targe extent, the power of the waves of the sea.

"The idea, however, is not new. I myself designed two 'anti-rolling tanks' 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 28 per cent."

"I do not think that these tanks could be fitted with oil ful, because it is difficult ito build tanks which'are oiltight." 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 new 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 experiment, they were temporarily discontinued, the passengers urged to have them put into use again.

Anti-rolling tanks would doubtfess prove of the greatest importance to men-of-war. A steady gun platform was almost indispensable to the gunner, 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 Philip Watts described the experiments on the old Inflexible, saying the water-chamber acted satisfactorily. The water, however, made a great noise. Water, too, added Sir John Thorneycroft, required an appreciable amount of space. It would be an advantage if they could use something heavier than water. Of comae, 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.