The working arrangements on board the Olympic and Titanic are necessarily on a scale in keeping with the great size of the vessels. The number of crew employed on board each ship for all purposes is about 860. Of these about 65 belong to the navigating department, 320 are employed in the engineers’ department, and 475 are engaged in the stewards’ and catering- department. The forward portion of the boat deck and the exposed decks at the ends of the vessel are entirely devoted to working and navigating appliances, while the management of the ship is also greatly facilitated by the working passage on the port side of E deck, which extends nearly the full length of this deck and is connected by stairways with all the principal departments.
Accommodation for Officers and Crew
The position of the officers’ accommodation will be seen from Plates III., IV. and V. The officers are accommodated in a house on the boat deck forward. The engineers’ quarters are on the middle deck, and their mess room, pantries, offices, etc., on the deck above adjoining the working passage. The firemen have excellent accommodation on five decks right forward. Access from their quarters to the boiler rooms is obtained by two spiral staircases and a tunnel through the forward holds, an arrangement which keeps the firemen entirely clear of the passenger accommodation. The seamen’s accommodation is placed on E deck forward. The living rooms for the stewards and catering staff are situated on the port side of E deck, and are entered from the working passage.
Cargo, Baggage, and Mails.
To provide access for cargo or baggage to the lower holds, three cargo hatchways, placed at the centre-line of the ship, have been fitted forward for Nos. 1, 2 and 3 holds ; four hatchways have been provided aft, two placed at the centre-line for Nos. 5 and 6 holds ; and two smaller hatchways, away from the centre-line, give access to No. 4 hold. The hatchways to Nos. 1 and 2 holds are served by three steam winches. The third hatch, that near the passengers’ quarters, is served by two 2½-ton electric cranes and two 3-ton electric winches. The two hatchways to No. 4 hold are each served by a 14-ton electric crane. The remaining hatchways, Nos. 5 and 6, are each served by-two 2½-ton cranes and one 3-ton electric winch. The masts, which have a height of 205ft. above the average draught line, are utilized for working the cargo by means of cargo spans, while the foremast supports a derrick suitable for lifting motor cars, which will be stored in one of the fore holds.
The post office and baggage accommodation is arranged compactly on the lower and orlop decks forward, with a view to expediting the reception and despatch of the mails and the transportation of passengers’ baggage on the departure and arrival of the ship.
The Navigating Bridge.
The navigating bridge, from which the vessel is controlled, is situated at the forward end of the boat deck, so that the navigating officer may have a clear view ahead. This bridge is a veritable forest of instruments. In the centre is the wheelhouse, containing the telemotor control wheel by which the ship is steered, with a standard compass immediately in front. In front of the wheelhouse are placed the engine room, docking, and steering telegraphs, and loud-speaking telephones to various stations. In the bridge shelter or chart room adjoining are also placed the watertight door controller, the submarine-signal receiver, the helm indicator, the master clocks, and other apparatus.
The steering gear is situated in the poop at the after end of the shelter deck. It is of the well-known Wilson-Pirrie type, made by Messrs. Harland & Wolff themselves, and consists of a spring quadrant and tiller on the rudder-head worked through wheel-and- pinion and bevel gearing by either of two sets of tliree-crank vertical steam engines. Either engine suffices for the working of the gear, the other being a standby. The whole arrangement is illustrated in Fig. 139. The engines have inverted direct-acting cylinders, each 17in. diameter by 18in. stroke, which take steam at a pressure of 1001b. per sq. in. Piston steam valves have been adopted, and work directly from the crank shaft by means of eccentrics. The cylinders of each engine are supported at the front by three wrought steel columns, and at the back by three cast iron columns, two of the latter also forming supports for the intermediate shaft, which connects the spur and bevel gears. Each engine is so arranged on a sliding bed with adjusting screws that it can be quickly put into or out of gear with the quadrant, when it is desired to change from one engine to the other.
Fig. 139.—Steering Gear.
The crank shaft of each engine is provided with a spur-pinion which drives a spur-wheel on the intermediate shaft, carried on the back columns of the engine. This intermediate shaft is con¬ nected by bevel gearing to a vertical shaft, which in turn gears into the quadrant by means of a manganese bronze pinion situated above the bevel gearing. The gearing will be better understood by reference to Fig. 139, and is also well shown in the photograph of the engines given in Fig. 140. The spur and bevel gear are of the Citroen type, made of cast steel throughout, and have machine-cut helical teeth of the herring-bone shape, which experience has shown to be the most suitable form for minimum wear when the gears have to transmit power in either direction, as is the case with a steering engine. The sizes of the spur wheels are as follows:—pitch circle diameters, 14¼in. and 69¾in. ; number of teeth, 18 and 87 ; pitch, about 2½in. ; width of face, 9½in. The pitch is given approximately as the Citroen gears are not made to standard pitches. Their noiseless running is mainly obtained through a total absence of back-lash, and this can only be achieved by calculating the exact pitch according to given diameters and a fixed number of teeth. For this reason a special cutter is made for each set of gearing. The sizes of the bevel wheels are :—pitch circle diameters, 5ft. 10½in. and 2ft. 0½in. ; number of teeth, 19 and 55 ; pitch, about 4¼in. ; width of face, 11in. The teeth on both sides of the face are shrouded to the pitch line, and the total width over the shrouds is 14½in. The weight of each bevel wheel is 1 ton 16 cwt., and each, spur wheel weighs 1 ton 6 cwt. The spur pinion weighs about 5 cwt., and the bevel pinion about 9 cwt. The quadrant and the pinion on the vertical shaft have machine-cut involute teeth.
Fig. 140.—Steam Steering Engines with Spur and Bevel Gearing.
The quadrant is connected to the arms of the working tiller by means of heavy spring links, which prevent undue shocks coming upon the gear or the engine. The working tiller consists of two forged arms, one arm being placed at the centre of each half of the quadrant. The tiller arms are keyed to the rudder-head, and are tied together by a strong wrought steel tie-bar. A spare tiller, arranged to come into operation only if the connection between the quadrant and working tiller is disabled, is placed immediately above the quadrant. This tiller can also be worked by the warping capstans should the whole gear be disabled. The steering gear is controlled from the naviga¬ ting bridge by Brown telemotors, and from the docking bridge aft by mechanical means. The telemotor cylinders are placed near the steering engines, and are connected by levers and shafting to the steam control valves on the engines. The control valve on each engine is fitted with an economic valve of Brown’s type, which shuts off the steam automatically when the engine is at rest, and so prevents the leakage of steam into the cylinder. The precise position of the rudder at any moment is shown by means of an electric helm indicatoUplaced on" the navigating bridge. This indicator, which is illustrated in Fig. 141, has been supplied by Messrs. Evershed and Vignoles, Ltd., of London.
Mooring and Warping Arrangements.
Special attention has been devoted by the builders to the mooring arrangements of the new vessels. It was realized that a size of ship had been reached for which the usual arrangement of two bower anchors was insufficient, and it was decided to have, in addition to these, a centre anchor worked by a wire rope through the extra hawsepipe in the stem, to which reference has already been made. The centre anchor, which is illustrated in Fig. 142, weighs 15½ tons, and the side anchors each weigh 7¾ tons. The cables used in connection with the side anchors are 3⅜in. diameter and have a total length of 330 fathoms, weighing in all 96 tons. The anchors are of Hall’s latest improved type, and, with the cables, have been manufactured by Messrs. N. Hingley & Sons, Ltd., of Netherton, Dudley. A strongly built crane is fitted at the centre-line of the forecastle deck for handling the 15½-ton anchor, which is placed in a well on the deck immediately abaft the stem. The side anchors are housed in the hawse-pipes in the usual manner.
The wire hawser used in connection with the centre anchor is 94in. circumference and 175 fathoms long, and has been supplied, in the case of both the Olympic and Titanic, by Messrs. Bullivant and Co., Ltd., of London. These hawsers, together with the thimbles and splices necessary, were guaranteed by the makers to withstand a breaking strain of 280 tons. At the request of the Board of Trade, one thimble and splice were tested to destruction at Cardiff in the presence of their surveyor, with the result that the test specimen broke near the tail of the splice at a load of 289 tons.
Fig. 142.—15½-ton Anchor.
The introduction of the centre anchor has necessitated an addition to the usual Napier windlass gear in the form of a large grooved drum for winding the 9½-in. hawser mentioned above. This drum, which is placed on the shelter deck right forward, is driven through worm gear by one of the windlass engines. The windlass drums, or cable holders, for winding the cables are placed on the forecastle deck, as shown in Plate IV. and in the view of the forecastle deck given in Fig. 33, page 35. Each drum is mounted upon a vertical spindle, which is carried down to the shelter deck. Upon the lower end of each spindle is keyed a bevel wheel of large diameter, which is driven by worm gearing from one of the vertical windlass engines situated under the forecastle. Clutch-engaging and brake gear has been fitted and every detail embodied to ensure the satisfactory working of the cables under all conditions.
Ample arrangements have been made for warping the vessel in harbour. The forward gear for this purpose consists of four capstan drums placed on the forecastle, and one at a lower level for handling smaller ropes. The two foremost capstan spindles are driven by worm and bevel gearing in a similar manner to that adopted in the case of the windlass drums. The same engines are arranged to perform either of these duties, a system of clutches enabling the windlass drum to be thrown out of gear while the engine is working the capstan drums, and vice versa. The second pair of capstan drums are driven independently by vertical engines placed on the shelter deck beneath them. Similar warping capstans are installed at the after end of the ship. At this end there are five drums with four steam engines, one of which actuates two capstans.
For securing wire hawsers and warps, a large number of mooring bollards have been provided. These bollards are of very large size, as will be seen in the view of the forecastle deck, Fig. 33, referred to above.
Boats and Davits.
The lifeboats, which are 30ft. long, are placed on the boat deck, as shown in Plate IV. The davits are of the Welin double-acting type manufactured by the Welin Davit and Engineering Co., Ltd., of London. Sixteen sets, specially designed for handling two or, if desired, three boats each, have been provided. The double-acting system is not altogether new, as it was adopted by another company some time ago in the case of boats carried on the poop, but its employment on such a large scale is a distinct departure. The well-known principle of the Welin davit is retained in all its simplicity, with the addition of a slight segmental increase at the inboard edge of the quadrant. This modification enables the arm to be swung right inboard so that it may plumb the inboard boat, and thereby save the time-wasting operation of shoving and pulling the latter into position, which has to be done with davits of the ordinary type.
The arrangement for saving fore and aft deck space is also worthy of notice. Instead of having two separate standards between each boat, the standards are combined in the form of a twin frame ; see Fig. 143. The latter carries the two quadrants and all the necessary gear for operating the forward and after boat at will. The operating gear is also of an ingenious and interesting nature. For this purpose a single handle is employed, driving a small pinion, which is mounted upon a swing bar. The latter is thrown into or out of gear by means of a simple eccentric arrangement, which enables either screw of either davit to be worked independently of the other.
For hoisting and lowering the boats, four 15-cwt. electric winches have been provided in the positions shown in Plate III. A description of these winches, which have been supplied by the Sunderland Forge and Engineering Co., will be found in the chapter on the electrical equipment.
The compass outfit consists of four Lord Kelvin’s latest patent standard compasses, supplied by Messrs. Kelvin and James White, Ltd. Two of these compasses are placed on the captain’s bridge, one on the docking bridge aft, and one on an isolated brasswork platform in the centre of the ship (see Plate III.), which is built up from the boat deck 12ft. above all ironwork and 78ft. above the water-line.
Adjacent to the navigating bridge are two Lord Kelvin’s patent motor-driven sounding machines, arranged with spars to enable soundings to be taken when the ship is going at a good speed. The design of the machines is well known, but the latest pattern embodies an improvement in the form of an illuminated dial for night use. The illumination is provided by an electric lamp fitted on the top of the machine. The arrangement is such that the dial rotates, and only the figures adjacent to a pointer on the lamp case are illuminated.
Both the Olympic and Titanic have been fitted with the Submarine Signal Co.’s apparatus for receiving submarine signals. With this system the sound of submarine bells is received through the hull of the vessel. By locating the direction of the sounds, the position of the vessel, when in the neighbourhood of the coast can be accurately ascertained. The bells are established by the Trinity House and the lighting authorities of the United States, and over 120 are now in operation. The system is a great improvement upon that of aerial fog signals, as the latter, owing to the variations in the density of the atmosphere, are frequently misleading; and water, being constant in density, allows the sound to travel without any interruption at a speed 3¼ times greater than its rate of transmission in air.
Fig- 144—Receiving Tank for Submarine Signals.
The signals are received by small tanks containing microphones, placed on the inside of the hull of the vessel on the port and starboard sides below the water level ; see Fig. 144. These tanks, which may be termed the “ears” of the ship, are connected to a direction indicator on the navigating bridge (Fig. 145) by ordinary telephonic cable. By moving the switch on the indicator box to port, the port “ear” only is in operation. By changing the switch to starboard, the starboard “ear” commences its work. Assuming the bell to be on the port side of the ship, it is only by that “ear” sounds are received. Should, however, the bell be dead ahead, the sound will be heard equally by both “ears.” The signals, therefore, not only give warning of the ship’s proximity to a point of danger, but also assist her progress in a fog, as the navigating officer can by their aid tell with more certainty where the ship is located.
Fig. 145—Direction Indicator for Submarine Signals.