426 



NATURE 



[March i, 1900 



and the fixed or guide blades being similarly formed and pro- 

 jecting inwardly from the case and nearly touching the shaft. 

 A series of turbine wheels on one shaft were thus constituted, 

 each one complete in itself, like a parallel flow water turbine, 

 but unlike a water turbine, the steam after performing its work 

 in each turbine passed on to the next, preserving its longitudinal 

 velocity without shock, gradually falling in pressure on passing 

 through each row of blades and gradually expanding. Each i 

 successive row of blades was slightly larger in passage-way than j 

 the preceding, to allow for the increasing bulk of the elastic | 

 steam, and thus its velocity of flow was regulated so as to ! 

 operate with the greatest degree of efficiency on each turbine of 

 the series (Fig. i). 



All end pressure from the steam was balanced by the two 

 €qual series on each side of the inlet, and the revolving shaft lay 

 on its bearings revolving freely without any impressed force 

 except a steady torque urging rotation, the aggregate of the 

 multitude of minute forces of the steam on each blade. It con- 

 stituted an ideal rotary engine ; but it had faults. The com- 

 paratively high speed of rotation that was necessary for so small 

 a size of engine as this first example, made it difficult to prevent, 

 even with the special bearings described, a certain spring or 

 whipping of the massive steel shaft, so that considerable clear- 

 ances were found necessary, and leakage and loss of efficiency 

 resulted. It was, however, perceived that all these defects 

 would decrease as the size of the engine increased, with a corre- 

 sponding reduction of rotational velocity, and consequently 

 •efforts were made towards the construction of engines of larger 



turbine was an exceptionally economical heat engine. With a 

 steam pressure of loo lbs., the steam being moderately super- 

 heated, and a vacuum of 28 inches of mercury, the consumption 

 was 27 lbs. per kilowatt hour, which is equivalent to about 

 16 lbs. of steam per indicated horse-power. This result marked 

 an era in the development of the steam turbine, and opened for 

 it a wide field, including some of the chief applications of motive 

 power from steam. At this period turbine alternators of the 

 condensing type were placed in the Newcastle, Cambridge and 

 Scarborough Electric Supply Company's Stations, and soon 

 afterwards several of 600 horse-power of the non-condensing 

 parallel flow type were set to work in the Metropolitan Com- 

 panies' Stations, where the comparative absence of vibration 

 was an important factor. Turbine alternators and turbine 

 dynamos of 2500 horse-power are now in course of construction 

 in England and the United States, and larger sizes are in 

 prospect. 



A turbo-alternator manufactured at Heaton Works, Newcastle- 

 on-Tyne, for the Corporation of Elberfeld in Germany, was 

 tested a few days ago by a committee of experts from Germany, 

 Prof. Ewing being also present, with the following remarkable 

 results. At the full load of 1200 kilowatts, and with a steam 

 pressure of 130 lbs. at the engine, and 10° C. of superheat, the 

 engine driving its own air pumps, the consumption of steam was 

 found to be at the rate of 18 8 lbs. per kilowatt hour. To 

 compare this figure with those obtained with ordinary piston 

 engines of the highest recorded efficiencies, and assuming the 

 highest record with which I am acquainted of the ratio of elec- 



FiG. 2.— The Viper. 



■Size, which resulted, in 1888, in several turbo-alternators of 120 

 horse-power being supplied for the generation of current in 

 electric lighting stations, and at this period the total horse-power 

 •of turbines at work reached in the aggregate about 4000, all of 

 which were of the parallel flow type and non-condensing. 



In .1889, in consequence of partnership difficullies and the 

 temporary loss of patents, the radial flow type of turbines was 

 -reluctantly adopted. This type of turbine consists of a series of 

 fixed discs with interlocking flanges at the periphery, forming, 

 when placed together, a cylindrical case with inwardly project- 

 ing annular discs. On the shaft are keyed a similar set of discs, 

 the faces of the fixed and moving discs lie a short distance apart. 

 From the faces of the fixed discs project the rows of guide-blades 

 which nearly touch the moving disc, and from the moving disc 

 -project the rows of moving blades which nearly touch the fixed 

 •disc. 



The steam is admitted into the case between the balance piston 

 on the left and the first fixed disc, and passes outwards through 

 the rows of fixed and moving blades between the first fixed and 

 moving discs ; then inwards towards the shaft at the back of the 

 first moving disc, then again outwards between the second fixed 

 and moving discs, and so on to the exhaust ; the action being 

 the same as in the parallel flow type. 



In 1892, this type was the first to be adapted to work in con- 

 junction with a condenser. The first condensing turbine of the 

 radial flow type was of 200 horse- power, and at a speed of 

 .4800 revolutions per minute, drove an alternator of 150 kilowatts 

 output. It was tested by Prof. Ewing, and the general result 

 •of the trials was to demonstrate that the condensing steam 

 NO. 1583, VOL. 61] 



trical output to the power indicated in the steam engine, namely 

 85 per cent., the figure of 188 lbs. per kilowatt in the turbine 

 plant is equivalent to a consumption of 1 1 -9 lbs. per indicated 

 horse-power, a result surpassing the records of the best steam 

 engines in the production of electricity from steam. 



Turbine engines are also used for generating electrical current 

 for the transmission of power, the working of electrical tram- 

 ways, electrical pumping and coaling, and similar purposes. 

 They are also used for coupling directly to and driving fans for 

 producing forced and induced draught for general ventilating pur- 

 poses, also for driving centrifugal pumps for lifts up to 200 feet, 

 and screw pumps for low lifts. 



The most important field, however, for the steam turbine is 

 undoubtedly in the propulsion of ships. The large and increas- 

 ing amount of horse-power and the greater size and speed of the 

 modern engines tend towards some form which shall be light, 

 capable of perfect balancing and economical in steam. The 

 marine engine of the piston type does not entirely fulfil all these 

 requirements, but the compound turbine engine, as made in 

 1892, appeared to be capable of doing so, and of becoming an 

 ideal marine engine. On the other hand, an element of un- 

 certainty lay in the high speed of the turbine engine, and to 

 couple it directly to a propeller of ordinary proportions would 

 have led to failure. 



In January 1894, a pioneer syndicate was formed to explore 

 the problem, those chiefly associated in the undertaking being 

 the Earl of Rosse, Christopher Leyland, John Simpson, Campbell 

 Swinton, Norman Cookson, the late George Clayton, H. C. 

 Harvey, and Gerald .Stoney. It was deemed expedient, for 



