DISCUSSION ON MAY MEETING PAPERS. 29 



provement to the extent of about 20 per cent could be made in fuel consumption by using 

 steam superheated to 200 degrees and by other improvements. 



3. The oil engines run at a lower speed than those used by the authors. A reduction 

 in weight and cost can be effected by the use of higher speed engines, if this is considered 

 advisable. 



4. The engine-room and deck auxiliaries are based on British practice and are more 

 liberal than those used on Danish type motor ships. We considered this was desirable to meet 

 American requirements. 



5. Changes in costs and economic conditions will also modify the comparison. 



I desire to point out two important characteristics of the Diesel installation, the first 

 being favorable and the second unfavorable. 



1. The fuel consumption and the cost of fuel are extremely low. 



2. The weight and first cost of the installation are extremely high. 



It would seem that the trend of development should be towards reduction of weight, 

 and it is believed that not until a substantial reduction of weight is effected will the Diesel 

 engine have material advantages for American conditions, sufificient to induce its general 

 adoption. 



In general our conclusions in regard to Diesel engines are : 



1. That Diesel engines are not advantageous for all services, and the most economic 

 type of machinery will depend on the particular conditions to be met. 



2. Turbine machinery with high superheat will prove more advantageous for ordinary 

 voyages and moderate fuel prices. 



3. The Diesel engine will be advantageous for long voyages and high fuel prices. 



4. From the information available, it appears that a successful single-screw installa- 

 tion will have a considerable advantage for most cargo steamers. (Applause.) 



The Chairman.' — Mr. Smith wishes nqw to speak on the Warriner paper. 



Mr. Smith : — Mr. Warriner has contributed a very valuable paper, which is of especial 

 interest at this time. There are a large number of geared-turbine vessels in service, and the 

 present trend, more especially in Great Britain, is toward the general adoption of geared 

 turbines for marine propulsion. 



Geared turbines have been adopted by our Navy Department for all surface vessels 

 except battleships and battle cruisers. Great Britain and Japan have adopted this type for 

 all surface vessels. The British battle cruiser Hood is equipped with geared turbines which 

 develop 150,000 horse-power. The machinery of this vessel has been a marked success and 

 has advantages in weight, space and economy in steam consumption which it will be difficult 

 to surpass under similar conditions. The machinery of this vessel is of especial interest in 

 comparison with our electrically driven vessels. 



Geared turbines have been adopted by many British steamship companies for the largest 

 and finest of their recent passenger steamers, including the Cunard liners Scythia and 

 Samaria, the Anchor liners Cameronia, Tiburnia and Tyrrhenia, and the Pacific Navigation 

 liners Orduna, Orbita and Oropesa. This type has also been widely adopted by British 

 owners for cargo and channel steamers. 



American owners have not been as progressive as the British in adopting geared tur- 

 bines, although several have apparently adopted this type. There are, however, many geared- 

 turbine vessels under the American flag, most of which were built for the Shipping Board 



