98 ENGINEERING PROGRESS IN THE U. S. NAVY. 



the weights of main propelUng engines, condensers, all auxiliary machinery in the 

 engine-rooms, together with the weight of water included in pumps, piping, and 

 condensers, and in addition the weights of the handling gear required for use in 

 overhauling reciprocating engines in the case of the Delaware, and the turbine in 

 the case of the Utah, the difference in weight due to the last item alone being very 

 great. The weights given do not include anything outside of the engine rooms. 



Mr. Anderson makes the statement, in speaking of the engine-room floor area, 

 that it is of interest to note that the Delaware is not being repeated. In reply to 

 this I would say that the floor area required in the later ships was fixed so as to 

 permit the installation of turbine machinery should such installation appear desir- 

 able in the light of late developments, and advantage was taken of this increased 

 area to idealize in laying down the arrangement of reciprocating engines and their 

 auxiliaries. This latter type of machinery could have been accommodated in much 

 less area had we so desired, but it would have been at a sacrifice of this idealization. 



As to the relative maneuvering qualities of vessels driven by turbines and 

 reciprocating engines, the turbine advocates do not hesitate to admit that it is a 

 mistake to have reciprocating-engine vessels and turbine vessels in the same squad- 

 ron, on account of the inferior maneuvering qualities of the turbine vessels. 



Mr. Anderson further calls attention to the excess possible speed of the turbine 

 vessel as compared with that of the reciprocating-engine vessel. In answer to this 

 I would reply that if in designing the turbines the designers hewed as close to the 

 line as do the designers of reciprocating engines this excess possible overload of the 

 turbines would not exist, and therefore the excess possible speed would disappear. 

 This over design of turbines for our battleships has resulted in making the ships 

 over-engined, so that the only guards against excessive over drive of the boilers 

 are the capacities of the feed pumps, feed lines and steam lines, the turbines being 

 of such size that they will take all the steam that we can give them. 



Finally, I do not wish it to be considered that this article was presented for the 

 purpose of increasing antagonism to the use of turbines for propulsion of naval 

 vessels. Such is not the case. I only desire to point out that the range of the tur- 

 bine in which best results can be obtained is Umited, as is also that of the reciprocat- 

 ing engine. Taking our present battleships of 21 knots speed, with the powers 

 which we have used up to date, the advantage rests decidedly with the reciprocating 

 engine, but should the power necessary to obtain this speed be increased to any 

 great extent above that which is required for the New York, Texas, and the new 

 vessel, the Pennsylvania, we would be driven almost necessarily to the turbine for 

 our main propelling unit, and the probabilities are that when such becomes the case 

 we will find the reduction gear has come into its own. 



I wish to thank the Society of Naval Architects and Marine Engineers for the 

 courtesy with which the article has been received. 



The President: — You will agree with me that this paper which has been 

 presented to us is a most interesting contribution to the records of our Society, and 



