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March, 1910 been strong enough there is no rea- son why she should not be floating today. As to the desirability of giving in tables for the scant- lings, that would no doubt be a very good thing to have, but it has been impossible, as I said before, to get to that practical point yet. I have not got facts enough and tests enough to approach that part of the subject yet, In @ satisfactory amatner, "so° 1 had to limit mself to the theoretical consideration. Of course, on the face of it, that looks somewhat interesting. It was mentioned that a bulkhead deflected 2 in--I have seen a bulk- head which deflected 6 in. and al- though it was not quite water-tight, such a paper there was considerable leakage at the seams, still it was not a serious mat- ter, and the ship could easily be kept afloat with the pump. That was in the imperial yacht the Standard built for the Czar of Russia--that bulkhead. TAc. MarRINE. REVIEW was strengthened with one or two horizontal stiffeners, I cannot remem- ber I think that bulkheads will generally stand a great amount which. of deflection before they break down, and for a considerable time, and then there will be usually leakage on the seams, and that is a point I have not touched on in this paper, leakage along the seams in a large bulkhead may become a serious mat- ver, and the pumps may not be able to keep the vessel afloat. Chairman Stevens: Was not that the cause of the loss of the Republic? The Case of the Republic. Prot, Hovesard: In. the Republic that seemed to be the case; there was a great deal of leakage; the ship sank deeper. and deeper. 'When tthe relief vessels came, she was 6 ft. by the stern, and, of course, the water in the compartments was thus very much increased, and the and- the. height of: 105 pressure on the bulkheads was very great indeed. ~ Chairman Stevens: I believe the chief engineer of the Republic stated that one good steam pump would have saved the ship if he could have kept it going. Prof. Hovgaard: Quite possible. I wish there'° was some one here who could give further data on the loss of the Republic. I was hoping some one would come forward and discuss this point. Chairman Taylor: -<The thanks ot the Society are certainly due to Prof. Hovgaard for the paper, the value of which will probably grow greater and greater as time extends, and that is really the true measure of the value of a production of this nature. E. T. Keyser's paper on "The De- velopment of the Gasoline Power Boat" and James H. Warrington's paper on "A System of Mathematical Lines for Ships' were read by title only. The New Westinghouse Marine Steam Turbine Drive HE November Marine Review contained the of the Melville-Macalpine re- duction gear appearing in any American publication. We present here- with a description of the hydraulic brake devised for testing out the gear. Although the apparatus was designed primarily for marine use in order to permit of the use of a high speed tur- bine in conjunction with a moderate or low-speed propeller, it should be equally applicable in other cases where a pos- itive and compact connection between the prime mover and the driven ap- paratus is desired. Incidentally while permitting of the use of positively con- nected turbines and propellers, each run- ning at its most efficient speed, it also makes for a substantial reduction in space and in weight, the latter not only in itself but in reduction in fuel carried due to the higher economy attainable by reason of taking fullest advantage of rotor speeds nad steam velocities. A most complete series of tests were un- dertaken by the Westinghouse Machine Co., East Pittsburg, Pa., builders of the gear, in order to determine its capacity and efficiency and in order to do so it was necessary to provide some form of brake or dynamometer that would, be capable of absorbing a continuous out- put of 6,000 effective horsepower, and first description - the following particulars. of this brake and of the tests conducted therewith are from information supplied by the West- inghouse Co, A brake of this capacity was in its way as entirely unprecedented as the gear itself. In any form of mechanical brake, the energy is transformed into heat, and in dealing with such large powers as were contemplated, the problem of car- rying away the heat generated becomes a very serious one. An ordinary band or "Prony" type of friction brake was entirely out of con- sideration, as the speed would limit the diameter of the brake wheel to 6 or 7 ft., and its face would have to be not less: than 30 ft. The difficulties involved in the construction, and the cooling of such a brake, and the maintenance of the proper tension on a brake band of this width are practically insurmount- able. For a number of years, the Westing- "house Machine Co. has successfully em- ployed a form of hydraulic brake for measuring the power developed in the works tests made on all steam turbines manufactured by it. This form of brake consists of a rotor mounted on a shaft coupled to the shaft of the turbine, and rotating within a closed casing sup- ported on journals through which the rotor shaft passes. The casing is held against turning by means of a radial arm bearing against a vertical strut, the lower end of which rests on an or- dinary platform scale. Within the cas- ing is a quantity of water, which quan- tity may be maintained constant at any desired amount by means of inlet and outlet pipes with adjustable controlling valves. The rotor has a series of vanes or teeth on its periphery which tend to impart a rotary motion to the water contained in the casing. The inner sur- face of the casing is provided with vanes or teeth which resist this tend- ency, and the result is a powerful brak- ing action, the intensity of which can be regulated by the quantity of water in the casing. The resistance which the casing must offer to prevent its being rotated by the water striking its in- wardly projecting vanes at high velocity is measured by the pressure exerted on the platform scale by the strut under the radius arm, and from this pressure, the effective length of the radius arm, and the number of revolutions per min- ute, the power is calculated in identical- ly the same manner as in the case of an ordinary Prony or band brake. As a matter of course, the temperature of the water is quickly raised to the boil- ing point, and a considerable portion of it evaporates, and in the form of steam easily carries off the enormous quan- tities of heat generated. The amount of fresh water admitted to compensate