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32 THE Marine REVIEW The Electrical Equipment of the Cunard Express -- Steamer Mauretania In the equipment of a modern steam- ship great improvements have been made in recent years for the economical work- ing of the vessel and for the comfort of the passengers. Of all the changes that have been made, none have been more welcome and so thoroughly appre- ciated as the introduction of electric ~ light. The first vessel to be fitted was the American steamer Columbia, the lighting of which was carried out under the di- rection of Mr. Edison in 1880. There were 115 lamps of 10 C. P. and two dy- namos driven by belts from a counter- shaft. In December, 1881, Professor Andrew Jamieson delivered a lecture to this in- stitution, in which he stated that electric lighting was fast replacing oil lamps on steamships, and gave a description of the installation fitted on .the Cunard steamer Servia at. a cost of £1,000. When I mention that the total cost of the electrical installations on each of the latest Cunarders has been about £65,000, some idea will be formed of the great progress electrical engineering has made within the last 26 years. © aa Since the introduction of electricity : on board ship, it has proved. itself to be the "acme" of petfection for light- ing, and has not only added greatly to the comfort of passengers, but has enable ship owners to utilize lower deck spaces. to better advantage for passenger accommodation; and _ not only passenger vessels have benefited by the adaptability, safety, and econ- omy of electricity, but the ordinary cargo steamer of the present day is taking full advantage of it for the safe and rapid handling of cargo. No first class cargo steamer is now complete without electric light, and ship owners are finding a great many charters can- not be secured unless their vessels are lighted electrically. While it would be interesting to fol- low the development of the various systems of electrical installations on ship board since the introduction of the first 6-K. W. machines on the lit- tle steamer Columbia, to the 1,650 K. W.. in four machines on the Maureta- nia, I can only make a brief reference to some of the more important points. In the earlier designs of dynamo construction, the generators were run *Paper read before the Institution of Engi- neers and Ship Builders of Scotland. ae BY MR. W, C. MARTIN. at a very high speed, and in many vessels the power of the engine was transmitted by belts or ropes and countershafts to the dynamos. Belts on board ship are most objectionable, not only on account of the great space required, but because of their unsteadiness. Many attempts were made in the early days to produce some means of connecting the slow- speed engine and high-speed dynamo without belts, but even the most suc- cessful arrangement devised, namely, friction wheels, was found unsuitable for all but the smallest powers. Noth- ing really reliable for ship work was in use, until the advent of the high- speed steam engine made it possible to couple engine and dynamo directly fogetner...in fact, if was this «very demand for a suitable engine that led to the development and perfection ot the high-speed engine and steam tur- bine. The choice of an engine for electric power on 'board ship is about equally divided between the slow-speed type. * at from 200 to 300 revolutions, and the high» speed ot from 500 to 700 R. P. M., while an occasional engineer pre- fers a turbine. Engineers in charge hot these. plants claim to have the most satisfactory results regarding efficiency and economy; but, undoubt- edly, the steam turbine is the ideal for ship work. It has all the advantages of light weight, less space, steadier driving, higher efficiency under certain conditions, freedom from _ vibration, and, having no _ reciprocating parts, there is less wear. It has been proved that, in smaller sizes, the turbines are not so economical in steam consump- tion, but it is almost certain that this will be overcome, and in the near future the 'turbo-driven dynamo will become universal. Since the first installations many new fittings and devices have been in- vented for safe, reliable working on board ship, and the most important of these is the system of wiring, and the protection of the same. The first insulated wires used for ship lighting were covered with cotton cloth and white lead, and a further protection of rubber tubing when passing through specially damp places. One of the greatest difficulties in ship lighting has been to find wires and fittings that would not be affected by sea air and water, and it still re- mains a fact that, no matter how good the quality of the insulating material and armored protection may be, if the wires haave not been well laid by. ex- perienced men, deterioration sets in quickly with most disastrous results. Any electric installation fitted today with the best material and workman- ship should last as long as the hull of the ship. - Ship builders dare not ig- nore certain standard rules in the building of a ship, but in some in- stances they are not so particular with regard to the lighting of the same, and it would be to the interest of all concerned if insurance registries and the board of trade took a more intel- ligent interest in this kind of work. In preparing an installation to be fitted on board ship, particular atten- tion should be paid to the placing of the wires, so that they might always be accessible and above all things they should be proof against fire and water In the Cunard steamer Servia there were 117 Swan lamps and two arc lamps equal to about 10 K. W. of 13.4 H. P. In the Mauretania the total output of the four electric generators is about: 2,200 E. H.. P., while the ace tual power required for all the lights and motors running at one time is afro tt P. It ts found in general practice that, the power being very intermittent, two generators are capa- 'ble of doing the work, thus leaving a large margin in hand for emergencies. To find space for such powerful plant and to fit the installation on the safest and most reliable system, pre- sented some interesting problems. The first of these was to determine the most suitable type of steam generator. After due consideration, the Cunard company and the builders of the ves- sel decided to adopt the steam tur- bine, by the use of which the space required was reduced to a minimum, with less weight and more freedom from noise or vibration as compared with ordinary high-speed engines. There are four sets of Parsons' turbo continuous-current generators, each dynamo is shunt wound and is : capable. of giving an output of 3,750 amperes at 110 volts and 1,200 R. PB M. These generators are placed on an elevated platform abaft the engine ' a