SHIPBUILDING 



will only b of the nature of a catalogue. Fur a 

 time the White Star liners maintained first place 

 in the matter of speed, being exceeded, however, 

 a* respects dimensions and tonnage by tin- >'iti/ <if 

 Berlin of the Iniiian Line, produced in the same 

 year, and for a time the longest ves.se! afloat next 

 to the (treat Eastern. Roundly stated, the Itrit- 

 annir reduced the passage to and from Queen-town 

 and New York to 8J days. In 1879 two fn-li com- 

 petitors were in the field, the Arizona of the Guion 

 Line, Imilt hy the Fairtield Company and the 

 Gallia of the Cunard Company, built* by .1. and 

 ('.. Thomson. Clydebank. During 1880-81 the 

 Canard Company added the Servia to their fleet, 

 from the stocks of Messrs J. and G. Thomson ; the 

 Inman Company added the City of Rome (subse- 

 quently transferred to the Anchor Line fleet), from 

 the stocks of the Barrow Company ; and the Guion 

 Company the Alaska, from the Fairfield yard. 

 After them came the Oregon (Fairfield), for the 

 Guion Line, in 1883; the Aumnin (Clydebank), 

 for the Cunard Company, in the same year ; the 

 America (Clydebank), for the National Line, in 

 1884; and the Umbria (Fairfield) and Etruria 

 (Fairfield), for the Cunard Company, in 1885. The 

 average time between Sandy Hook and Queens- 

 town during 1886 was about 6 days 15 hours as 

 compared with 11 days 19 hours in 1856. A table 

 of speeds and dimensions of representative Atlantic 

 steamers is appended. 



Britannic . . . . 



Arituna 



SvrrU 



Alaska 



City of Roma . . 



Oregon 



America . . . . 



Umbria 



Etruria 



Olijr of Parta . . 

 Aufiilta Victoria 

 Columbia . . . . 

 Teutonic . . . . 

 Norman nla . . . 

 Flint Ulimarck . 

 Campania .... 



lad. 



Horw- 



6,600 

 6,300 

 IOM 



10,600 

 11.890 

 7,375 

 7,354 

 14,:t2l 

 14,320 



M,O 



14,110 



18,0110 

 16.SB2 



18,412 



;tn,oi 



tiu. 



16 



17 



16-9 



18 



18-23 



18-3 



17-8 



19 



192 



21-8 



18-31 



10-16 



21 



19-34 



20-7 



23 



Turin-tcrfw Steamers. In 1888-89 four still larger 

 and more powerful steamship were afloat these 

 were the City ofNne York, City of Paris, Majestic, 

 and Trutunir inaugurators of the twin-screw c|M>cli 

 of Atlantic navigation. Of the same da were 

 the twin-screw vessels built and owned by ( Jeriimn 

 and French firms, the Normannia, Avffutfa Vic. 

 /ori/>,and Furst Bismarck of the Hamburg American 

 Line, La Touraine of the Campagnie Traiisatlan- 



recognised as nnadvisahle to transmit the total 

 IKIWIT through one line of shafting. The ri-k- 

 run through ini-ha] to the shafting or pro|M-llers 

 of single-screw Mcanier- i. 'reive only too freipient 

 illustration, and the concurrent decrease in .-ail 

 power makes the consequence- greatly n 

 oils. With twin-screws, each driven liy a separate 

 set of engines and shafting, ships can. in the event 

 of a break-down to one set of machinery, still pur- 

 sue their voyage by means of the other set. The 

 twin-screws can also be used to assist the steering 

 in case of emergency. The duplication of the en 

 ginesalso permits of a complete central water tight 

 bulkhead, greatly increasing the chance of safety 

 in case of collision. 



Turbines. The latest development in propeller.-. 

 consists of engines on the turbine priti' 

 WATKIM-OWKR), steam being the motive ]>\ver 

 and acting directly on turbines enclosed in tube-. 

 The screw shaft, again, is acted on directly by 

 the turbines, which weigh about one fifth of an 

 ordinary steam-engine. The 7W/</<'torpcdo-lioat, 

 with three such turbines, made 4-J'. miles ]>er hour 

 at Bpithead during the review in IMC 



Water-tight Subdivision. Subdivision of the hull 

 by strong water-tight Bulkheads (q.v. ) has un- 

 doubtedly become the essential factor in the safe- 

 guarding of .steamships against foundering through 

 collision or grounding on rocks. In the event of 

 the shell being penetrated and an inrush of 

 water taking place, the inflow is con- 

 lined to the space between two bulk- 

 heads, and there is reserve of buoy- 

 ancy enough in the remaining com- 

 Cments to keep the vessel afloat 

 ly of the high-class mail and 

 passenger ships on the Atlantic and 

 elsewhere are so minutely subdivided 

 that even in the contingency of any 

 two compartments being lai(f open to 

 the sea as in the case of the shell 

 being penetrated precisely in the line 

 of a dividing bulkhead the vessel 

 would not sink. In the case of purely 

 cargo-carrying vessels the commercial 

 and other conditions imposed are such 

 as restrict the degree and nature of 

 subdivision, but even in vessels of this 



Quleksit 



I'Mttarfr 



(Kutward). 



The next triumph was the con-t ruction at 

 Fairfield for the Cunard Company of the < 'IIIHJHIH m 

 and I.IK-IIIIIII, two powerful twin-screw \e--els. 

 which l-gan to ply in 1833. In .lantiury Is'i'i \va- 

 bandied at Belfast by Messrs Harland \- Wolff 

 the While Star liner llrrnnir, the biggest ship ever 

 built ; length (over all) 704 ft., breadth (is ft., depth 

 4! It., with a displacement of 28,500 tons. 



Twin -crews hare been employed in steamers for 

 particular tervieM for many years, notably in those 

 for roasting and cross-channel work, where depth 

 of water is restricted, and in vessels of the navy, 

 win-re BMWMVriaf facility wits and is a desidera- 

 tum. The comparative efficiency of single-screw 

 mid twin-screw steamers is Mill the subject uf 

 debute by naval architects, but the conditions 

 under which the evolution of the Atlantic 'ex- 

 ].!-- -i<-:imship must nroceed make it ini|M-rative 

 that twin screws should form the agents of pro- 

 |nil-iiiii. In vi-ss<-ls having engines which develop 

 i.h.p. ranging from 13,000 to 20,000 it has been 



class the system is being more and more developed. 

 These very conditions, curiously enough, encourage, 

 nay demand, the extended application of the prin- 

 ciple of subdivision in another part of the hull 

 structure of cargo-carrying vessels, sailing as well 

 as steam viz. throughout the bottom. The carry- 

 ing of water-ballast (see BALLAST) has for vefy 

 many years lieen imposed on vessels compelled by 

 the exigencies of service to proceed light or par- 

 tially loaded, and this same need, associating itself 

 with the structural requirements arising from the 

 growth in ships' dimensions, ha.- resulted in 

 the general adoption of water-ballast l>ottoms on 

 the subdi visional or 'cellular' principle. This 

 modification in the internal features of a ship's 

 stincture dates from before the time of the (/m/C 

 /.'/A/I/-/I, in which, its well n in previous smaller 

 ships built by Scott Kussell, the cellular system 

 received thorough illustration, although not associ- 

 ated with water-ballast That it contributes im- 

 mensely to the security of a vessel in the event of 

 its grounding on rocks or other sunken obstacles is 

 of course easy to understand. Not only is the 

 length of the -hip subdivided by transverse bulk- 

 heads as already explained, hut the top of the 

 cellular bottom or 'inner shell' is in all vital 

 res|>ect8 as water-tight, though necessarily not so 

 thick, as the outer skin of the ship. 'We are 

 enabled through the courtesy of Messrs William 

 Denny and Bros., shipbuilders, Dumbarton a linn 



