One of the differences between the Mauretania and the Lusitania is, that in the former vessel, a greater use of high-tensile steel has been made, which has resulted in a reduction of weight and increasd capacity for car- rying fuel and deadweight cargo. Most of the riveting of the bottom, upper shell plating, and part of the decks was'done by hydraulic. pressure. The Mauretania has nine decks, the lower orlop, orlop, lower, main, up- per, shelter, promenade, boat and sun decks. The promenade, boat and sun decks are above the main structure of the vessel. A tier of deck houses, running for about half the length of the ship, is erected on the boat deck, the whole being surmounted at the fore end by the commander's bridge, which is about 100 ft. above the keel. The fore ends of the deck houses are curved, so as to' reduce wind resist- ance as the vessel steams ahead. To ensure the safety of the ship in the event of collision, the subdi- vision by watertight bulkheads and decks is the most elaborate that could be devised for a passenger vessel, the number of separate watertight com- partments --175--rendering the ship practically unsinkable. All watertight doors fitted to the main bulkheads are so atranged that they can be in- stantly closed in case of accident, the apparatus for performing this opera- tion being worked by hydraulic pow- er, electrically controlled from _ the bridge, where there are indicators which always show at a glance wheth- er each watertight door is open: or closed. About 26,000 steel plates were used in the shell, decks, bulkheads, casings, etc., of the vessel. Over 4,- 000,000 rivets were worked into the ship, weighing 700 tons. The main piece of the stern frame, which is of cast steel, weighed very nearly 50 tons. The balanced rudder is formed of steel castings which are hollow and shaped to reduce resistance. The rudder head, 25%4 in. in diameter, is of forged ingot steel. The parts are bolted together, and have a_ united weight of about 64 tons. The rud- der and steering gear are entirely be- low the water-line, for additional pro- tection in the event of the vessel be- 'ing fired upon if used as an armed cruiser in time of war. The total weight of the main castings, includ- ing rudder, stem bar, stern frame and propeller brackets, exceeds 200 tons. THE PROPELLING MACHINERY. The Mauretania's turbines and boil- ers, with coal bunkers, occupy a total length of from 400 to 450 ft. amid- ships, with a depth from the main THE Marine Review deck to the double bottom. The coal bunkers along the sides of the ship are so arranged that they will afford protection to the most vital and im- portant parts of the vessel if used as a: scout or cruiser in time of war. For the same reason the principal machinery is placed below the water- line of the ship. Two high-pressure and two low-pressure turbines are provided, each having a separate shaft and each driving one propeller. The total power developed is about 65,000 to. 70,000. LB BP... so. that. exon ot the Mauretania's four propellers ex- erts nearly 24 times the power of the paddle steamer Britannia, the first Cunard. steatner. Throughout, the machinery of the new vessel (includ- ing the steering gear and engines) has, as far as possible, been dupli- cated, so that in the event of accident she can always be worked by one set of engines. When the engines are running, the rotating mass in the en- gine rooms weighs 600 tons, and this weight revolves at about 200 revolu- tions...per minute;...So0. great 15. tue accuracy necessary in the construc- tion of turbine machinery that the whole must be, under control and measurement to. the one-thousandth part of an inch and balanced to an ounce. Some of the larger castings which form the low-pressure turbine casings weigh 38 'tons each. The weight of the ingots from which the large drums were forged was 120 tons each. About 1,500,000 _ blades have been fitted in the turbine ma- chinery, and if these blades were placed end to end they would extend a distance of about 110 miles. Steam is supplied by twenty-three doubie-ended and two single-ended boilers, having 192 furnaces in all. Air is supplied to the boilers by How- den's system of forced draught, the fans being driven by electric motors. If the boilers, which are arranged in the ship in four stokeholds, were _ placed on end one above the other, they would form a column 547 ft. high, or about one-tenth of a mile. The four elliptical funnels rise 152 ft. above the keel of the vessel. It placed on their sides they would form an elliptical tunnel inside of which two locomotives of the ordinary type could pass each other. On the occa- sion of the launch of the Mauretania, the vessel's funnels lay on the ground end to end at the works of the Wall- send Slipway Co., and many of the visitors were driven in motor cars through the tunnel thus _ formed, which had a total length of 430 ft. Lunch could be taken in one of the funnels by 250 people comfortably and 41 seated at tables. The aggregate length of the steam and feed pipes in the machinery rooms is. about 1% miles. Independent of the pipes for steam and water connections, there are about 144 miles of brass and steel tubes in the boilers, condensers, etc. As will be readily understood, the coal consumption to drive the Maure- tania across the Atlantic is very great. It is 'computed that, for a trip from Liverpool to New York and_ back, about twenty trains, each with twenty large trucks of coal, would be re- quired. Approximately, 350 firemen and trimmers will be required to deal. with the coal. PASSENGER ACCOMMODATION. , The passenger accommodation of the Mauretania when its spaciousness and beauty of decoration are taken into account, certainly justify the use of the somewhat extravagant term, "a floating palace." It is claimed that the vessel offers 50 per cent more light and air space and deck prom- enade per passenger than any other liner afloat with the exception of the Lusitania. The following list gives the accommodation provided: First-class: passengers: (4 ii... ste. Second-class passengers .........0...5.. 475 Third-class: passengers = ...0.0) 03-32. .: 1,300 CLOW ie eas ee eee ieee 800 Total ok ea as Vas ae ee ae 3185 There are in all 253 staterooms for first-class. passengers, 133 for second- class, and 278 for third-class. THE FIRST-CLASS ACCOMMODATION. _ The accommodation for first-class passengers placed amidships extends over five decks--the main, upper, shel- | ter, promenade and _ boat, decks. Access from one deck to another is obtained by means of the grand and other stair cases, and by two sepa- rate electric passenger lifts, which travel from the main to the boat deck. -- The greater part of the accommo- dation for passengers, officers and crew has been carried out by the ship builders in their own workshops: This includes all the second-class pub- lic' rooms, the _ first-class corridors, the majority of the first-class staterooms. The following work has 'been done by sub-contractors: The first-class lounge and library, by Messrs. Ch. Mellier. & Co., London; the first-class dining rooms, smoking room, the grand entrances, 54 special staterooms, and the regal suites, by Messrs, Turner, Lord & Co., Lon- don; the children's room and sixteen special staterooms, by Messrs. Rob- son & Sons, Newcastle-on-Tyne. The grand entrances and _ staircase are, in the style of the sixteenth cen- tury, Italian. -The. woodwork is in French walnut, the panels being ve-