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16 their large vessels for the Canadian ser- vice, in the Virginian and Victorian of 15,000 tons displacement. The ordinary mean speed attained on regular service across the Atlantic is rather more than 17 knots, and the highest average speed from land to land has been slightly un- der 18 knots. © . In the Pacific, also, a turbine liner, the Maheno, has now begun to run be- tween New Zealand and Canada. The Loongana, moreover, now trading be- _ tween Australia and New Zealand must be mentioned among turbine steamers, if only because on her maiden voyage she went out to Australia in 30% days at an average speed of 15 knots, as fast an average speed as that attained by the vessels carrying the weekly mails. As marking a further step in the prog- ress of the turbine, after the Allan liners must be named the Cunarder turbine- propelled Carmania, which is of 30,000 tons displacement. . She, like other tur- bine steamers, has some advantage in speed over a sister vessel (in this case the Caronia), launched a few weeks ear- lier, and propelled by quadruple expan- sion engines, and, altogether, the results in Service of this vessel have, it is un- derstood, been extremely satisfactory. The Carmania, however, is. herself over- - shadowed by the two giant steamships already mentioned. These two vessels are being built, one' on the Clyde and one on the Tyne, and are expected to be put into com- mission for regular service between I[.iv- _erpool and New York some time next year; they are very similar, though not identical, in lines and dimensions, and will be by far the largest and fastest ocean steamers ever constructed. Their length is nearly 800 ft., and their breadth approaches 90 ft; the displacement will be at least 40,000 tons, and they are ex- pected to have an average service speed of 24% to 25 knots, even in moderately - rough weather. To maintain this speed the power of the main turbines will be far greater than has ever been installed on board any ship. The very great horse- power developed will be distributed over four turbines, each of which will drive its own propeller shaft; in addition, there will be two turbines for the purpose of reversing. ~ Each vessel will have six decks, and a feature of the complete arrangements on board is that there will be electri- cally-worked lifts for facilitating com- munication between the decks. The elec- tricity required for these, and for other labor-saving appliances, as well as for the lighting of the vessels throughout, ' will be generated by four turbine-driven dynamos. That is to say, each steamer will have a central electric supply sta- tion of a capacity only exceeded at the TRAE Marine. REVIEW present day by some eighty towns in Great Britain, and corresponding to that of a town, say, as big as Ipswich, with a population of about 70,000. | Even on turbine-propelled ships there is, as a rule, still a certain amount of vibration perceptible, owing to the em- ployment of small reciprocating engines for the air pumps, and the other aux- iliary machinery of all kinds necessary on board ship. It seems possible, as on these new Cunarders, to obviate this, discomfort by the introduction, in' place of such engines, of motor-driven pumps, -etc., and turbine-driven dynamos for gen- erating the necessary electricity. In this way hardly a tremor should be felt, and in the saloons it should be almost im- possible to detect whether the steamer's engines are at work or not. There seems no reason to doubt that in these very large and fast liners un- 'precedented and phenomenal results as regards speed, economy of coal, and cost of upkeep and engine-room staff will be attained, advantages which should be accompanied by a great increase of com- fort to all on-board. It only remains to remind the reader that in most of the comparative trials re- ferred to, the turbine is being compared 'with modern triple and, in some cases, quadruple-expansion engines, which em- body all up-to-date improvements, that is to say, with the reciprocating engine at its very highest stage of dévelopment. According to Lloyds Register at the beginning of this year, out of sixty-eight vessels with a speed exceeding 20 knots, ro fewer than ten use Parsons turbines in place of reciprocating engines. It must further be remembered that whereas ~so lately as five years ago there was only one passenger steamer afloat fitted with turbines, this summer nearly all regular passenger services between Great Britain 'and Ireland and Great Britain and the Continent steamers. We may venture to predict that the turbine will ere long entirely supersede the reciprocating engine in vessels of 16 knots' sea speed and upwards and over 5,000 indicated horsepower. This fore- cast might probably be extended to in- clude vessels of speeds as low as 13 knots if of 20,000 tons and upwards, possibly to include vessels even lower in the scale, in course of time. As things act- ually stand at present, within the limits of what we may call the above-named most suitable field, is comprised some- thing like one-fifth of the total steam tonnage of the world; nor must it be forgotten that whilst the speed. of ships tends to increase and the turbine to im- prove, so also will the class of vessels suitable for the turbine become larger in like proportion. are performed by turbine To take a final survey of results achieved and of future prospects. Up to the present time this country has led the way in the development of the tur- bine, but it can hardly be doubted that just as engineers abroad have not been slow to see the advantages gained by the use of turbines on land for driving. elec- tric dynamos, so they will quickly turn to practical account the advantages to be derived from the employment of the same on ships. Such competition may be healthy; it is at any rate inevitable and must be faced. Meanwhile the fact that twenty-five of the greatest and most fa- mous British ship building and engineer- ing firms have already taken up the manu- facture for ships of turbines of the Par- sons type is doubly reassuring. On what lines, it may be asked, can these future developments be looked for? It must be admitted, to begin with, that in a slow vessel, say, of 10 knots, it does not at present seem possible to: re- place reciprocating engines entirely by the turbine, for the following reason. _ The small number of revolutions at which the propellers are driven would mean, for reasons already stated, a tur- bine of so large a diameter as to make the cost and weight prohibitive; while, on the other hand, it is impossible to increase materially the propeller revo- lutions by using a smaller propeller with- out greatly impairing the efficiency. Difficult as the problem. looks, at the present time, of attempting to replace the reciprocating engine altogether by turbines, yet there is apparently a gap that the turbine can even now most use- fully fill. The engines of the ordinary coasting cargo tramp cannot, or at any rate do not, make full use of the steam raised by their boilers. After the steam has passed through the engines, a 'large amount of unused energy is wasted on its passage into the condenser. 'Three- quarters of this wasted energy can be utilized by a turbine--an additional aux- iliary turbine we will call it--to be driven simply and solely by this steam, techni- cally known as "exhaust steam." In this way, the steam, by help of the aux- iliary turbine, instead of being wasted, will give additional power to drive the steamer, amounting to something like 20 per cent, at the extra cost of not a single pound of coal. It is claimed that the fastest work done at the head of the lakes in un- loading soft coal was in discharging tie Cargo of the steamer P: - G: Walker, at the new Hanna docx at Superior a few days ago. In seven- teen hours working time with three Mead towers, the cargo of 7,152 tons was unloaded. This was at the rate of 142 tons per hour per hoist.