Like all the other boats of the seventies and early eighties, the _Oceanic_ was a single-screw vessel. The advantage of double propellers in case of accident had long been recognized, but hitherto twin-screws had not proved as efficient as a single screw in developing speed. But in 1888 the _City of Paris_ (now the _Philadelphia_) a twin-screw boat, began making new speed records, and the following year her sister ship, the _New York_, and the new _Majestic_ and _Teutonic_, entering into the ocean-record contests, cut the time of the passage between Europe and America to less than six days. The advantages of the double-screw over the single are so many and so manifest as to leave no question as to their superiority. The disabling of the shaft or screw of the single-screw steamer, or the derangement of her rudder renders the vessel helpless. Not so the twin-screw ship; for on such ships the screws can be used for steering as well as propelling. And it has happened many times that twin-screw ships have crossed the ocean with the steering gear disabled, or with one screw entirely out of commission. THE TRIUMPH OF THE TURBINE In recent years the greatest revolutionary step in steamship construction has been the invention and development of the turbine engine, the mechanism of which has been described elsewhere. Since the day of the little _Turbinia_, whose speed astonished the nautical world, the limit for size and speed of ships has again been materially advanced, and no thinking person will venture to predict restricting limits without a modifying question mark. At the beginning of the twentieth century a keen rivalry had developed between England and the Continent for supremacy in transatlantic traffic, America having dropped out of the race. The Germans in particular had produced fast boats, such as the _Deutschland_ and _Kaiser Wilhelm II_, which for several years held the ocean record for speed. But meanwhile the turbine engine was being perfected in England, the land of its invention, and presently turbine "greyhounds" began crossing the ocean and menacing the records held by the boats equipped with the older type of engine. The reciprocating marine engine, however, had been steadily improved, until it was a marvel in efficiency. Quadruple expansion engines driving twin-screws of a size and shape known to develop the greatest efficiency, for several years offered invincible competition to the new type of engine. There were new conditions to be met, new difficulties to be overcome.