90 ENGINEERING PROGRESS IN THE U. S. NAVY. 



battleships and what they were for. As I understand the matter, a battleship 

 operates in a squadron with other battleships, and if it should happen that two or 

 three battleships in a squadron have a couple of knots of extra speed, they cannot 

 use this to any advantage, as they cannot go off by themselves. In the case of 

 the battle cruisers and destroyers, however, they do go on and operate by themselves 

 and for that reason the advantage of having one or two, or any additional number 

 of knots speed up your sleeve, would be a very important element, more so than it 

 would be in the case of battleships. 



I would join with the last speaker and ask Mr. Anderson about the subject of 

 weights. 



Mr. Anderson: — With regard to the question of machinery weights, the 

 different items included in the total given for each ship, are as follows : — 



Displacement: — Delaware, 20,000 tons; Utah, 21,825 tons; Wyoming, 26,000 

 tons. 



Delaware, main engines and lagging, throttle valves and fittings, forced lubri- 

 cation casings on engines, pipes and tanks, exhaust pipes to condensers, two con- 

 densers each 11,788 square feet C. S., all shafting, spring bearings and stern tube 

 bushes, propellers and nuts, air and circulating pumps, 654.50 tons. 



In the case of the Utah and Wyoming, as follows: — Turbines and lagging, 

 turbine regulating valves and pipes, all valves and pipes between turbines, forced 

 lubrication system, tanks and coolers, exhaust bends to condensers, two condensers, 

 Utah, 15,225 square feet C. S. each and Wyoming 14,008 square feet C. S. each, 

 all shafting and spring bearings and stern tube bushes, propellers and nuts, air 

 and circulating pumps and including vacuum augmentors for Utah. Total for 

 Utah 659.01 tons and for Wyoming 648.23 tons. 



The author gives the following engine-room weights in wet tons :— Delaware, 

 773.26; North Dakota, 785.93; Utah, 919.80. 



These weights include all the engine-room fittings, but the Utah is not on a 

 comparable basis with the Delaware and North Dakota, for the reason that there is 

 additional machinery in the Utah which is not installed in the Delaware or North 

 Dakota. 



Naval Constructor Robinson: — I am unable to quote the exact figures, 

 but I am in the fortunate or unfortunate position of having to float this stuff. 

 (Laughter.) I know that in every single case when we get a weight for reciprocating 

 engines and a weight for turbine engines for the same design, there is a difference. 

 I cannot, offhand, say just what is the difference ; possibly it may be that the basis 

 of calculation is somewhat different, but when it comes to calculating the displace- 

 ment of the ship, you have to put additional displacement in to float the difference, 

 whatever it may be due to. Similarly, it is often the case that I have to make as- 

 sorted insides for these ships, one to take reciprocating machinery and one to take 

 turbine machinery, and I am very much convinced, from the information we have, 



