ELECTRIC AUXILIARIES ON MERCHANT SHIPS. 183 



est advantage, on tankers it is not so apparent. On this latter point we would take some issue, 

 as it is possible to furnish motors entirely enclosed, gas and watertight, or where location 

 on tank vessels renders the same desirable to furnish forced ventilation through the enclosed 

 motor casings. Several tank vessels in this country have already been equipped in this man- 

 ner, and there are others under construction. 



With regard to the question of economy of engine auxiliaries on steam-driven vessels, 

 Mr. Dickinson has furnished some interesting figures, although we feel that perhaps his as- 

 sumption for the steam required for auxiliaries at sea is a little too high a percentage of tlie 

 total. The advantages obtained from the use of electric drive for all auxiliaries on motor 

 ships is, we believe, now apparent, and similarly the advantages of the electric drive for deck 

 auxiliaries on steam vessels as well as motor ships. The question, however, of the use of elec- 

 tricity for auxiliaries in the engine room on steam vessels furnishes the most debatable ground. 

 A certain amount of exhaust steam from engine auxiliaries is always diverted to feed water 

 heating, but beyond the point where exhaust steam can be used economically for this purpose 

 lies considerable possibility in economy for electric drive as well as the advantages of con- 

 venient operation and freedom from leaking steam pipes, etc. 



We heartily endorse the statement of the author in his last paragraph that engineers of 

 this country should combine their efforts and avail themselves of every opportunity to improve 

 the efficiency of our merchant ships to the end that they may be able to compete successfully 

 with the modem ships of other countries. In this connection, we were much impressed on a 

 trip this summer to the Pacific Coast, to find that numerous European and Scandinavian motor 

 ships, electrically equipped, were making regular trips through the Canal to the Pacific Coast 

 ports. In addition to the conducting of a satisfactory cargo-carrying business, these vessels 

 were buying California oil on the coast at $1.50 per barrel, sufficient for a round trip, this 

 same oil selling in their own home ports at $8 to $9 per barrel. 



President Capps: — Before giving the author of the second paper an opportunity to 

 respond, the Chair is of the opinion that it would add very much to the value of this dis- 

 cussion, if the Eng-ineer-in-Chief of the Navy, who is with us, would make some comments 

 on the papers and the discussions which have ensued. If he does not feel so prompted, of 

 course, it is his privilege not to respond. 



Rear-Admiral John K. Robison, U. S. N., Engineer-in-Chief : — About ten years 

 ag-o I was called upon to discuss an article presented by Mr. W. R. L. Emmet on the subject 

 of "Electric Drive," and I expressed then that I was from Missouri. Do you remember 

 that, Mr. Emmet? 



Mr. W. R. L. Emmet: — Yes. 



Rear Admiral Robison: — Well, I have seen a few things since. Concerning the 

 economy proposition, I can state for the benefit of the Society that on trial trips we have 

 had figures that have given us in no case so much as 0.9 of a pound of fuel per shaft horse- 

 power, under any speed between 10 and 21 knots. Within the last week, I attended a trial 

 where that took place. The best performance we have gotten on the trial-trip conditions is 

 on a geared-turbine drive, on a destroyer, which was 0.83 ; the best we have on the electric 

 drive is 0.86. 



Concerning the geared-turbine drive for the North Dakota, the current operating effi- 

 ciency of the ship has not been so satisfactory as we had hoped. We do not lay that to the 



