ENGINEERING PROGRESS IN THE U. S. NAVY. 89 



always be kept on hand, especially where ships are designed in units of 5 and 6, 

 like the New Jersey and Connecticut class; in fact, spare crank-shafts are carried 

 by many of our battleships. On the other hand, with turbine machinery it is dif- 

 ferent ; they would be kept in the yard for a considerable time, because the work 

 could not proceed any faster. 



In the case of the Paulding, trouble was experienced with the high-pressure 

 cruising turbine and it was taken out, and I believe she is to-day running without 

 that turbine. 



The engine-room of a turbine ship is considerably hotter than that of a recip- 

 rocating-engine ship, and anyone who has had experience with a hot engine-room 

 knows what that means. I speak from experience, because last summer I was in the 

 engine-room of the gunboat Marietta, where the thermometer showed 140 degrees 

 within about two feet of a forced draught ventilator. One can readily understand 

 the effect and the disinclination to work such an engine-room has on the personnel 

 of the engineer division. 



If, as Mr. Anderson states, no record has been kept of the amount of make-up 

 feed water, where does he get his figures in comparing the Delaware with the turbine 

 ships ? He also makes a remark which would lead us to believe that as we are going 

 to oil burners in battleships we will ultimately have to go to turbines. Why should 

 oil burners be used any more successfully in turbine ships than in those fitted with 

 reciprocating engines ? 



Mr. Anderson also says that they get more speed out of the turbine than the 

 reciprocating engine. This is largely due to what Captain Dyson says, that the tur- 

 bine is designed with more excess power than the reciprocating engine. If the 

 turbine can use every bit of steam that the boilers will supply, as Mr. Anderson 

 says, why could not the reciprocating engines, made slightly larger than the ones 

 put in the ships already built, do the same thing ? 



Mr. Anderson also talks about the detrimental effects of the high-pressure 

 steam, and states that a lower pressure should be used. I would like to ask what 

 effect this would have in the weights, especially on our torpedo-boat destroyers, 

 where the question of weights is a prime factor. He also states that the rotor 

 corrosion is a matter of carelessness, that the manholes are made so that they can 

 be examined, but no mention is made about the length of time required to raise 

 the casing and also the time required to replace it, should this be necessary in order 

 to check corrosion or for any other purpose. 



Naval Constructor Richard H. Robinson, Member of Council: — One of 

 the speakers who favored the turbine used the argument for it that a greater speed 

 can be secured. As I understand the paper of Captain Dyson, it is not intended 

 to indicate that the Navy Department makes any advocacy of reciprocating engines, 

 as distinguished from turbines, except possibly in a ship such as a battleship, which 

 is, comparatively, a slow-speed ship. This last summer I studied a good deal on 

 the subject of high-speed cruisers, and what they were for, as distinguished from 



