The following text may have been generated by Optical Character Recognition, with varying degrees of accuracy. Reader beware!

54 Mr. Emmet one question--it is prob- ably so simple a matter that he has not thought it necessary to mention it. However, it is not clear to my mind exactly how you balance the power between the generators and motors in cases where you reverse and slow down and start up, etc. W. L. R. Emmet:--The turbine is operated without the governor, the load goes off automatically, and the load comes on again. When I was on the Jupiter I did not do as many things as I would like to have done, -ae 1 was atraid the people: on her would be nervous about the machin- ery and the handling of it. I wanted minds to get used to the simple func- tioning of it, and I did not get them to do very much. I knew it would 'be done ultimately, and thoroughly experimented with, and it takes men's minds some time to get 'accustomed to that, and it is not desirable to hurry them. The only effect of lift- ing her propellers in the sea was to see the current cut down on _ the ammeters a little bit, and maybe shift a valve on the turbine. Another thing which I think is useful and is noticeable in the Jupiter is that the power required, as indi- cated by our measuring instruments, was less than we were told to ex- pect by the engineering department; that is, that we got a better propul- sion coefficient than' had been ex- pected. That fact, I think, may" be partially attributable to perfectly uni- form rotation of the propellers. Reversing at Full Speed Joseph HH. Linnard:--I ask Mr. Em- met if among the few experiments 'that were made, under the circum- stances he mentions on the Jupiter, there was any experimentation on the subject of quickly reversing at full speed ahead? It is known that brings very heavy strains on apparatus of any kind in propelling a ship, and is a pretty severe test of any machinery. Ernest H. B. Anderson:--This pa- per is of great interest to marine en- gineers for the reason that a great deal of matter has been written about this system, and this installation is the pioneer of its kind in the coun- try. It is rather disappointing that the 'final trial results are not avail- able, and that the difficulties which interfered with these trials appear to have been largely due to faults in the generating unit and not in the motive power driving the propellers, which is the real novelty of this in- stallation. In connection with the preliminary trials I should like to know if the vessel was fully loaded to the designed draught and the corre- 'estimated THE MARINE REVIEW sponding displacement of 20,000 tons. The test of the steam consumption per shaft horsepower for the turbine is exceptionally good, but I think this result was obtained whilst the machine was under test on shore and not during any sea trials. It is, however, in no way a con- clusive argument as a comparison with a sister ship having another type of machinery, for the reason that the shaft horsepower upon which the fig- ure was based is not given, but I be- lieve the original design called for an shaft horsepower of 7,000 for 14 knots speed of the vessel. Bureau of Steam Engineering The- estimates Mr. Emmet puts forward for an electrical installation for a battleship similar to the Penn- sylvania are interesting, but I do not see how he can justify himself in pub- lishing such figures until he has shown just what the system is capa- ble of in the Jupiter. With regard to the second last Paragraph of this paper: -l trust the author will see his way to withdraw this completely, for I consider it hard- ly seems to be a statement that should be made in the proceedings of this society. The navy department, and especial- ly the bureau of steam engineering, have given Mr. 'Emmet and his col- leagues' a splendid opportunity of proving their claims, and it is up to these gentlemen to make good and not belittle the marine engineers of the navy, who are forced to listen to all kinds of propositions submitted for their consideration. It is not my purpose or wish at this time to put forward any claims or advantages for other systems of propulsion, but solely 'to show the members of this society that I per- sonally consider the navy department has given Mr. Emmet every assist- ance in making his system a success. In. England a company has been formed, consisting of the leading electric engineers and one or two shipbuilders, and they have had to build and equip a ship at their own expense, and I feel certain they have not had the assistance of the gov- ernment financially. As you all prob- ably know, I refer to the Tynemont, which has propelling machinery some- what similar to that under discussion, and for a complete description and various criticisms of this interesting vessel I refer you to Engineer, Oct. 10 and 17, and also to many of the other technical journals published in England. In regard to the Jupiter, I got this morning the Journal of the American February, 1914 | Society of Naval Engineers, and there is a very full account of this ship in this issue, giving all the particulars of the turbines and the motors and everything in connection with the ship. Edwin A. Stevens Jr.:--I would back up what Mr. Anderson says about the ability of the engineers jn the United States navy. Although not connected with the service in any way at all, at the same time I was in the naval militia as an officer and came in contact with a number of the naval officers of the United States, and my respect for them as engineers -is very high, and I think that the statement which Mr. Emmet has made in the next to the last para- graph of his paper is putting it very broad. He says: ll my- first design for a warship made over four years ago had been accepted by the navy department, the vessel produced would have been very greatly superior in respect - to. . economy, © reliability, weight, simplicity and cruising radius to any ship. now aflaat, and ever since that time my case has been steadily strengthening through the great im- provements which have been made in high-speed turbines." In regard to economy we can rely, probably, upon certain calculations, although we do know that calculations go amiss sometimes. In regard to weight, the same thing applies there. In simplic- ity, we might or might not. It de- pends whether the mechanical engi- neer wants to have a lot of electrical devices to bother with. The two do not seem to go together, there are lots of men who succeed in the me- chanical line who cannot grasp the electrical line. Economy of System In regard to reliability, all I have to say is that I am surprised that a man of Mr. Emmet's ability and ex- perience should make a statement of that character. In my short and lim- ited experience, compared with that of Mr. Emmet, I would say that re- liability is something that we cannot tell anything about until we have actu- ally tried a thing in practice. I can- not understand Mr. Emmet making | such a statement. He might have reason to believe so, but to come right out and say it would be more reliable, I fail to see it, that-is, to accept it as a fact before it has been proved. In regard to economy, I do not think there is very much question but what the combination of reciprocat- ing engine and the turbine is an eco- nomical unit. My idea is that the combination of a reciprocating unit