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MARINE REVIEW 25 shelter forward. The hurricane deck will also be available as a promenade deck, being clear from end to end, except for the space required for stowing life boats and life-saving ap- paratus. The greatest interest of course centers in the engines of the new vessel. These will consist of three Parson's com- pound steam turbines as follows: One high-pressure turbine on the center line ship and one low-pressure on either side. Each turbine will control an independnt line of shafting and there will be three propellers, one on each shaft. The revers- ing turbines which will be of special size, will be incorpo- rated in the low-pressure turbines to admit of the boat being worked astern. Steam will be supplied by two large cylin- 'drical boilers. Propelling machinery will be capable of driv- ing the vessel at a speed of about 21 miles an hour. It is well known that the turbine does not reverse and consequently independent machinery has to be carried for that purpose. There has been some question as to whether the turbine is adapted to short runs, with the necessity of frequently touch- ing port, such as obtains on the runs on the great lakes, but it is quite clear that the Turbine Steamship Co. expects no trouble on this score. The illustration of the Turbinia, ac-, companying this article, will convey an idea of what this new turbine steamer will be like. Messrs. H. & A. Allan of the Allan Line of steamships, write to the Marine Review to say that they expect to place their new turbine steamer Victorian in the Atlantic service between Montreal and Liverpool next August. The Victorian will be the first turbine steamship to be engaged regulariy in the north Atlantic trade, and she will be by far the largest as well as the swiftest of the Allan fleet. This venture on the part of the Allan Line is probably the most daring thing that has been attempted in steamship circles in several years. It is daring because it is primal.. Undoubtedly the Allan Line believes the turbine system to have passed beyond the experi- mental stage and to be an assured success, otherwise they would not put to hazard so great a sum of money as is now involved in the construction of a modern liner. This radical departure of the Allan Line lends especial significance to the fact that the Cunard Steamship Co. has just ordered a 12,000-ton steamer to be equipped with turbines and throws an interesting side light on the deliberations of the Cunard turbine commission, which is investigating the availability of the turbine engine for the propulsion of the two Cunard flyers. These flyers are to maintain an average speed of 25 knots across the Atlantic ocean under guarantee with the Brit- ish government. The Victorian will be fitted in the most modern styie for upwards of 1,500 passengers, and it is expected by reason of the absence of the throbbing movement inseparable from the ordinary steam engine, and the rapidity and unbroken steadiness of revolution in her shafting and propellers, to be at once noiseless and steady in a seaway, even while exerting the whole of her great power. 'fhe shafting of the Victorian has been specially designed for the requirements of ocean and island navigation, and consists of three shafts with one propeller on each. In the Turbinia of which, as stated, an illustration accompanies this article, the low-pressure turbine is on the center shaft, with the high-pressure engines on the outside shafts. In the Victorian and on the great lakes tur- bine steamers, building for the Turbine Steamship Co., this order has been reversed, the high-pressure engine driving the center propeller while the low pressures are attached to the outside shafts. For the benefit of those to whom the name "turbine" does not convey any clear idea, it may be explained that the mode of producing rotary motion in the shafting and its attached propellers is, in principle, the same as that of the old-fash- ioned windmill, the force. in the turbine, however, being steam instead of wind, and-the angled arms and sails of the wind- 5 mill being represented in the turbine by metallic vanes set on the surface of a conical casting, which forms, by attachment, the forward end of the propeller shafting; these vanes, work- ing into counterpart flutings on a fixed, surrounding, hollow casting, complete the device. The steam, entering at the forward end of this combined arrangement of blades, can only find passage by forcing the parts attached to the shafts into rapid revolution. Rushing along with the momentum due to its volume and boiler pressure by means of powerful air pumps operating at the other end, the steam imparts a steady, unceasing, rotary movement to the propellers, utilizing to the best advantage the whole boiler power of the ship. Crys- tallized in a sentence the turbine claims over the reciprocating engine a saving of weight, cost, space, attendance, and up- keep, and smooth continuous action with no rubbing surfaces, and no thrust friction, for the thrust is taken by the steam itself. The Parsons turbines are of the parallel flow type, the general course of the steam through them being parallel to the axis of rotation. In each of the turbines steam enters at the forward end and streams aft through an annular space formed between the outside of a cylindrical boss, which is carried by the shaft, and the inside of a corresponding cyl- indrical casing in which the turbine is enclosed. In streaming through this space the steam passes alternate rings of fixed guide blades and moving turbine blades. Having traversed the series in the high-pressure engine it goes to the low-pres- sure engine on either side, where the same process is gone through, thence it finds its way to the condenser as in the ordinary type of marine engine. Now the reciprocating en- gine, with which almost everyone is familiar, is a far from perfect machine. Not more than 50 per cent. of the energy going into its help to drive the boat forward, but the pro- pulsive co-efficient of the turbine' is greatly in excess of that of the marine engine because of its more perfect form as every ounce of steam put into the turbine is helping to turn the shaft. Another special feature in connection with the turbine ma- chinery is the lubrication of the shaft, the oil being forced in at the bearings under pressure, and the speed of the en- gine is so great that it carries the oil with it round the shaft which is thus practically floating and revolving in an oil bath. Cases are numerous where the shaft having been exposed at the bearings after years of working have been found as dull as the day it left the makers' hands, with even the tool marks fresh upon it. This will give an idea how little wastage there is through friction, and suggests to the lay mind the smoothness and steadiness of the machinery. With the old type of marine 'engine it is apparent to every- one that the hurling of a great weight like a piston and piston rod from one end of the cylinder to the other, and back again at an enormous velocity must be altogether unscientific, as it involves great loss of energy, great stress on the work- ing parts, and considerable and distressing vibration. These have been overcome by the turbine, which bids fair to be the pioneer of a new era in ocean traveling. There is of course the fact the turbines cannot reverse, but in the Victorian re- versing turbines will be enclosed in the low-pressure casings, and thus this difficulty is eliminated. It should also be re- membered that the safety of a vessel depends not so much on its:speed astern as on the power to stop quickly, and this turbine as designed is an extremely powerful engine in stop- ping because of the peculiar construction of the blades. Thus when the turbines are rotating in a contrary action to the steam which is passing through them, a turning movement is exer- cised two or three times as great as when the engines are running in the direction they are made for, whereas in the piston engine there is practically the same force whether the engine is going with the steam or against it.