28 DISCUSSION ON MAY MEETING PAPERS. 



The figures for the cost of operation, on page 11, are considerably less for the steamer 

 and very much less for the motor ship than we found. It appears that both the operating costs 

 and the earnings for both vessels are optimistic for the freight rate specified. 



The table shows that there is a saving in the cost of the engine-room staff, but we 

 did not find this to be the case. It should be remembered that the Diesel vessel has twin 

 screws and requires more routine work and attention when in port. Fifteen' men were 

 allowed by us in both cases. 



The comparisons which we have made show that the earnings per year are about as 

 follows, based on conditions which prevailed some time ago : 



1. Voyag'e from New York to Hong Kong via Panama Canal — 



Steamer. Motor ship. 



Net earnings in per cent of first cost 11.32 13.47 



Net earnings in per cent of steamer .... 119 



2. Voyage from New York to Seattle, via Panama Canal — 



Steamer. Motor ship. 



Net earnings in per cent of first cost 14.73 1 1.4 



Net earnings in per cent of steamer .... 77.4 



This illustrates the fact that the earnings will differ with the character of the voyage. 

 The first voyage was based on the price of oil as given in Table I herewith; the second was 

 based on steam oil at $18.26 per ton and Diesel oil at $23 per ton. 



Table I. — Comparison Between Geared-Turhine and Diesel-Engine Machinery for Cargo 



Vessel. 



Length — 425 feet; speed, three-quarters loaded, 12 knots; displacement, full load, 14,050 tons; deadweight 



capacity, about 10,000 tons. 



Turbine. Diesel. 



S. H. P. for 12 knots, % loaded 3,100 3,020 



Weight of machinery, dry, tons 470.5 1,052 



Weight of machinery, wet, tons 560 1,060 



Weight of machinery, wet, per S. H. P. lbs 405 785 



Deadweight capacity, tons 10,050 9,500 



Bale capacity, cubic feet 497,000 493,000 



Voyage from New York to Hong Kong via Panama Canal. 



Turbine. Diesel. 



Oil consumption for all purposes, lbs. per S. H. P 1.08 0.45 



Fuel consumption per year, tons 8,978 3,468 



Fuel consumption, per cent of turbine 100 38.7 



Cost of fuel per ton (dollars) 23.85 29.90 



Cost of fuel per year (dollars) 214,000 103,700 



Cost of fuel per cent of turbine 100 48.5 



In connection with our comparison, the following' may be noted : 



1. Cheaper oil will be more favorable to the steamer. 



2. The steam plant is not the most economical and the lightest type, and further im- 



