224 



SCIENCE. 



[N. S. Vol. XI. No. 267. 



may be made to succeed or to fail, accordingly 

 as the officers of the Government, from the 

 President and the Secretary of the Navy down 

 to lieutenant and ensign, combine to insure its 

 success or conspire to insure a failure. It will 

 only be when every watch-officer, whatever 

 his grade, is made an efficient officer, both above 

 and below decks, that the modern naval fight- 

 ing machine can be made of maximum efficiency 

 under the existing system. Any disinclination 

 of either of the old types of officer to become 

 efficient in either old line of duty, results in 

 serious, perhaps very dangerous, inefficiency, 

 and a liability to failure at critical times. The 

 conversion of the navy from a sailing to a steam- 

 ing fleet, from an aggregation of sailing craft 

 into a collection of floating machines of wonder- 

 fully complicated mechanism, cannot be re- 

 versed ; but the change may prove most dis- 

 astrous during the period of transition if every 

 officer in the service does not display sufficient 

 patriotism to insure rapid and safe metamor- 

 phosis. It is here that the real risk lies and 

 the overcoming of confirmed habits, of prejudice, 

 and any indolence of the personnel, by reason, 

 sense and patriotism, must be relied upon to 

 insure success. 



The structural work of the navy has been 

 greatly promoted by the introduction of a new 

 structural material — nickel-steel ; which alloy 

 is now regularly furnished in any quantity and 

 in parts of any size, from five pounds in a rifle- 

 barrel to many tons in the shaft of a transat- 

 lantic or Naval steamer. This is an alloy of 

 ' mild ' steel, ingot-iron, with a small percentage 

 of nickel, resulting in greatly increasing the 

 limit of elasticity and the ultimate resistance 

 of the metal, without sacrificing its ductility. 



Electrically driven machinery has come to 

 be an important and very extensive element in 

 the construction and installation of details of 

 the machinery of every man-of-war. The ad- 

 vantages, where allowable or applicable, are 

 great ease of operation, convenience of energy- 

 transmission, and especially avoidance of heat 

 due to the transmission of steam to steam- 

 driven machinery about the ship, and a consid- 

 erable gain in economy, in many cases. The 

 disadvantages are stated to be excessive weight, 

 great delicacy, lack of adaptability to the con- 



ditions of everyday work at sea, and the occu- 

 pation of spaces below the protective deck, 

 where space is particularly valuable and diffi- 

 cult to secure for the apparatus of battle. The 

 admiral thinks the advantages of electrical 

 transmissions on shipboard somewhat exagger- 

 ated and that, within the machinery compart- 

 ments, at least, ' steam-drives ' are preferable. 

 He refers to the curious fact that, in the navy, 

 it has been the custom, very generally, to en- 

 trust the machinery of the electric transmissions 

 to the non-expert departments of the organiza- 

 tion. The experts in engineering are apparently 

 called in only when the responsible amateur 

 gets into trouble. As the presumably best- 

 informed man in the navy, on this subject, the 

 Engineer-in-Chief is entitled to most respectful 

 consideration and a full hearing, when discuss- 

 ing these matters of fact and principle in engi- 

 neering. 



The transformation in type of the marine 

 steam-boiler, from the older forms to the 

 'modern', 'sectional,' 'safety' or water-tube 

 type, appears, in the judgment of the respon- 

 sible expert authority of the navy, to have 

 been practically accomplished — a change which 

 was compelled as soon as the steam-pressures 

 needed to insure the now common and high 

 thermodynamic efficiencies of naval steam- 

 engines had attained figures beyond the safe 

 standards for ' shell ' boilers of the old forms. 

 Now that steam pressure is carried at from 15 

 to 20 atmospheres, the safer forms employed by 

 Fulton and Barlow in 1798, by John Stevens 

 1804-5, by Trevithick in 1810, by Gurney and 

 Hancock in 1830-35, and by them made suc- 

 cessful in earlier generations and by Babcock 

 aud Wilcox and Root later, have come per- 

 manently into use. It is somewhat remarkable 

 that they should have been first accepted bo 

 generally in the navy, where it has been a 

 tradition that the traditional is best. The 

 change is perhaps in part due to the introduc- 

 tion of a progressive spirit with steam, and 

 certainly largely through the appearance on the 

 scene of the young element now coming up 

 from the great technical and professional school 

 at Annapolis, where it has become imbued with 

 the scientific spirit of the time. 



R. H. T. 



