Forty Knots Over the Ocean.

New Zealand Graphic, Volume XL, Issue 7, 15 February 1908, Page 46

Forty Knots Over the Ocean.

There is a curious contrast between the way in which developments in fighting and merchant shipping are received by the average man. Every new battleship or cruiser design is regularly heralded as the “last word,” beyond which the wit of man can no further' go. Even eminent naval officers and architects declared that the Nile, built in 1888, marked the climax of battleship development, while the advent of the Drake in 1901 was very widely held to write “finis” to the armoured cruiser. Yet we have advanced from the 12,000 tons of the Nile to 18,000 in the Dreadnought, and from the 14,100 of the Drake to 17,250 in the inflexible; and, considering the energy with which improvements are being sought both at home and abroad, he would be a rash man who would say that the highest possible point in size and power has been reached even in these leviathens. With merchant ships and passenger liners tihe case is different, though why it should be no one can tell. Successive Atlantic record-breakers have never inspired this belief. They are recognised, as all creations of science should be, merely as steps in a progress of which no man can see the end—to which, may be, there is no end—and the twenty-five knots of the Mauretania and Lusitania is no more regarded as the ne plus ultra of Transatlantic speed than is the Nnlli Secundus of aerial navigation. TWENTY YEARS AGO. What for many years must remain the goal of marine architects was laid down more than twenty years ago by one of the most prominent ship-designers of the day. Sir William Pearce has just designed the Umbria and Etruria, which shattered all previous records by crossing the Atlantic at an average speed of nineteen knots, and in an address delivered shortly after to one of the learned societies of Glasgow he declared tihat he was ready, then and there, to produce a vessel which should accomplish the voyage at a speed of forty knots. If this could be done, it would reduce the Lusitania’s time by 50 per cent. . i It is not surprising that Sir William Pearce’s- statement was received with a good deal of scepticism. Even in these days the realisation of such a feat seems sufficiently far off, and in 1885 .twinscrews were only just coining into prominence, while the turbine, for marine purposes, at all events, was unknown. The difficulties to be overcome were, therefore, tremendous, and in order to combine the requisite horse-power with a capacity for paying its way as an ordinary cargo and passenger ship, it would, said Sir William, be necessary to give the vessel a length of 1,500 ft. and a beam of 150 ft. —- just about twice the dimensions, of the Lusitania. The cost of such a ship would have been fabulous. THE TURBINE. The progress of the last twenty .years, and most of "all the'adoption of the turbine as a marine engine, enable us to look upon Sir William Pearce’s boast with more credulity than was possible when he made it. If for the next thirty years we advance at the same proportionate rate as we have done for the last twenty, a 40-knot liner should be crossing the Atlantic in three days by 1940. The evolution of marine, architecture has been phenomenal. The last wooden liner was built in 1850, and the last iron liner in 1883. The last paddle-ship was the Scotia, of 1804; and Etruria, of 1885, was the last Now that the turbine has so completely vindicated itself, it cannot be many years before we come to the last of the recip-rocating-engined ships, and with the unhampered development of the turbine, forty knots will be'comparatively easily realisable. ,-There is at present no sea-going ship afloat which can do more than thirty-four knots an hour. The torpedo-boat destroyers, Viper and Cobra, the first tur-bine-engined warships ever built, each did well over thirty-six knots, but were both lost at sea. and swiee those;disasters the Admiralty has been content with comparatively moderate speeds. There is now building, however, a destroyer which bids fair to break all records. The Swift, a vessel of 1,800 tons —four times the size of the average destroyer-—now completing at the works of Messrs. Cammell, Laird, and Co., at Birkenhead, has a contract speed of thirty-six knots.

This alone is sufficiently remarkable for a vessel of her size, but it is an open secret that the builders and designers hope to get forty-two or forty-four knots out of her. THE COST. The displacement of the Swift is little more than a twentieth of the Lusitania’s, but her engines will develop 30,000 horsepower as compared with the - liner’s 72,000, and she will cost as much as four or five ordinary destroyers. Of course, the Swift could not cross the

Atlantic at thirty-six knots, or anything like it, since her oil-carrying capacity is limited to 180 tons, but the naval architect, if left to himself, would have no difficulty whatever in producing a ship capable of doing it. The trouble with such a ship would not lie with the naval architect, but with the civil engineer. Waters now traversed in perfect safety by the Lusitania and her. sister would become perilous, all existing- wharves and docks would be useless, and frequent docking is vital to a ship -which is to maintain her speed.