60 PROGRESS IN TURBINE SHIP PROPULSION. 



carrying three propellers. Tests were carried out in 1897 and 32.76 knots mean 

 speed per hour was attained. 



The application o£ turbines to marine propulsion became very rapid, and the 

 construction of the turbine as applied to the larger ships called for the greatest skill 

 of the designer, in regard to which no words of the author could pay adequate 

 tribute. 



The engineering skill required in the design of the modern high-speed geared 

 turbine bears no comparison to that required for such gigantic engineering un- 

 dertakings as the direct-connected turbines of the Mauretania, the Lusitania, or 

 the Carmania, for example. 



It became early apparent that, because of the disparity between the best speed 

 of the turbine and the propeller, there was a distinct line of demarcation, about 17 

 knots, below which the application of turbines was not economical, which naturally 

 debarred not less than some 90 per cent of the vessels afloat. 



In 1904 turbine marine propulsion had reached such stages that by the end 

 of that year some twenty-six vessels, aggregating 147,000 horse-power, were in ser- 

 vice, which created enough interest to lead George Westinghouse to consider en- 

 tering the marine field. 



At his instigation the late Admiral G. W. Melville, U. S. N., and Mr. John H. 

 Macalpine visited Europe in 1904 to report on the marine situation as it then existed, 

 and it is interesting to note that, in spite of the large number of vessels equipped in 

 Europe, the report was anything but encouraging. They did not see any opportunity 

 for the steam turbine for driving ships as compared with the existing reciprocating 

 engines, particularly in the case of ships which are required to operate at cruising 

 speeds, and they showed how inferior were the turbine installations as compared 

 with the reciprocating engine installations when so operated. They recognized the 

 applicability of the turbine to express steamers which always operated at their full 

 speed, and pointed out their lack of economy when applied to lower speed ships which 

 comprise the greater part of the merchant marine. They said, "If one could devise 

 a means of reconciling in a practical manner the necessary high speed of revolution 

 of the turbine with the comparatively low speed of revolution required by an effi- 

 cient propeller, the problem would be solved and the turbine would practically wipe 

 out the reciprocating engine for the propulsion of ships. The solution of this prob- 

 lem would be a stroke of great genius," and proceeded some time thereafter them- 

 selves to become the genii by designing a tooth reduction gear adaptable to such 

 service, embodying the now well-known floating frame. 



Mr. Westinghouse at once recognized the great possibility of its construction, 

 and though considerably delayed on account of the financial depression at that time, 

 a reduction gear expected to develop 6,000 horse-power, reducing from 1,500 to 

 300 revolutions per minute, was tested in 1909. 



The inventors recognizing that no gear was suitable for shipboard use that 

 was not capable of successfully operating with considerable misalignment, the gear 

 was operated with the pinion deliberately set out of alignment 0.020 inch in the length 



