22 DISCUSSION ON MAY MEETING PAPERS. 



Mr. Donald Mathieson, Member (Communicated) : — I wish to convey to Mr. Met- 

 ten and Mr. Shaw my regrets not being able, owing to strike trouble, to be at the meeting and 

 my congratulations for their excellent, practical paper which offers shipowners just the right 

 kind of information. 



Mr. John Martin, Member: — Mr. Chairman and members, it is not so much a dis- 

 cussion as it is a tribute I would like to offer for a moment. About ten days ago it was my 

 good fortune, representing the American Bureau of Shipping, to attend the sea trial of the 

 motor ship William Perm, equipped with Diesel engines by Mr. Metten and Mr. Shaw for 

 the Cramp Company. 



The trip was notable in the marine-engine history of this coimtry inasmuch as we have 

 just learned from the authors that the William Penn is the largest American ship fitted with 

 Diesel engines, and its successful trial performance marked another blaze in the trail the 

 end of which may be our ability to meet the lower operative costs of foreign ships and get 

 our share of the world's trade. 



On this trial the ship was stopped, started, run at different speeds over measured miles, 

 maneuvered in various ways such as ahead with starboard propeller and astern with port, 

 with helms alternately with and at variance with propellers, and finally a many-hour endur- 

 ance run, during all of which the engines and auxiliaries functioned perfectly with a notice- 

 able absence of vibration in all parts of the ship. 



I take this occasion to felicitate Messrs. Metten and Shaw upon their accomplishments, 

 and believe it would be of great interest to the members present to know how closely the 

 ship's performance met their estimates. Of this latter Mr. Shaw enlightened us tonight, and 

 I am sure you were very much interested to learn that the ship's performance met very nearly 

 their estimates. (Applause.) 



Mr. Chester B. Mills, Visitor: — With the chairman's permission I will endeavor to 

 throw a ray of hope into the hearts of the naval constructors of the coming generation. 



The advantages of the Diesel engine in economy of fuel over other prime movers has 

 long been recognized, and this type of engine is rapidly moving to the forefront where econ- 

 omy of fuel is a prime consideration. The disadvantages of the Diesel engine in its present 

 conventional form, however, are its complexity, great size and weight per brake horse- 

 power developed. A tremendous amount of energy and skill has been expended in attempts 

 made to simplify the design, eliminate the air compressor and lower the manufacturing cost. 



It will be of interest to members of the Society to know that one of the workers in this 

 field, Mr. E. A. Sperry, has struck out on a pioneer trail in the direction which will pro- 

 duce a heavy oil engine with a number of new characteristics, chief among which is its low 

 capital charge because of the greatly simplified construction, low weight per brake horse- 

 power, great economy of operation, and noticeable gain in space occupied by the engine and 

 machinery. The weight of this engine for the same power and revolutions is between one- 

 tenth and one-twentieth that of the conventional engine, and it will require approximately 

 one-fourth the floor space. What this means in the powering of a ship will be readily appre- 

 ciated by naval constructors. 



This engine as constructed is more efficient through the cariying out of compression 

 and expansion in two stages, with expansion to practically atmospheric pressure. It is noise- 

 less and bums, without carbon or smoke, ordinary bunker oil. Having fewer parts, its 

 mechanical efficiency is higher. High speeds are practicable through the employment of new 



