.'12 



sinni,A\v. 



made water-tight. In Rome 



plated over to form the deck, the deck plank being 

 laid on the plating, but in other cases plates are car- 

 ried along the sides of the vessel and wood only used 

 on the rest of the deck. 



When all the plating is on the ontsidc, and enough 

 of the inside of the vessel completed to give her 

 the requisite stiffness, she is ready for launching. 

 Launches are usually times of enjoyment, and great 

 crowds turn ont to see them. While launches are, 

 as a rule, successful, and the ship glides most easily 

 and gracefully into the water, rarely failing to make a 

 bow to the lady who christens her, it must not be 

 forgotten that to transfer a moss of thousands of Ions 

 fiom supports on land to the buoyancy of the water 

 is one of the greatest of engineering feats, mid there 

 are few ship-builders who do not heave a sigh of re- 

 lief when they see their vessel well water-borne. 



The vessel rests on the keel blocks, and on each 

 side of the keel blocks is placed a track or ground 

 way, at an inclination of about U of a " " lc " to ''"' 

 foot These extend well out into the water. Ou 

 top of these are placed the sliding ways, forming a 



the beams are designed that aro very light for the horw> pover de- 



velojK-d, the engines and boilers of the Vesuvius 

 weighing, when the boilers and condenser are full of 

 water, only 250 tons, and developing on this weight 

 4200 horse-power, giving a KJKTI! of 21. (io knots per 

 hour. When a tank is not available for model cx- 

 j>riments, the performance of some vessel already 

 built is taken a-s a basis from which to estimate tho 

 required horse-power. The resistance to be over- 

 come is of three kinds : The frietional resistance of 

 the water, which forms tho greater part of the resist- 

 ance at low speeds; tho eddy resistance, due to sudden 

 changes of shape or projections ; and the wave resist- 

 ance, which increases most rapidly at high M 

 These are all studied by the naval aicliiteet, and 

 every care is taken to keep the bottom clean and 

 well painted to diminish the friction, to get the fair- 

 est lines to decrease the eddies, and to chooso 

 properly tho general dimensions so that the \\avtn 

 raised at the required speed may require the least 

 expenditure of power. 



Tho outlook for the ship-builder in America is ex- 

 cellent. With onr largo and constantly increasing 



carriage or slide to support the vessel. coasting fleet, w -herein the cheap iron ship with 



The sliding ways are built up to the vessel, and when economical engines is lapidly becoming a necessity, 

 all is ready for launching wedges are driven in above with excellent rates for freight, anil vi.h the v- 

 the sliding ways. In this way tho weight is token j vessels fast disappearing, there must be for many 

 on the slidings and the keel blocks are knocked out, j years to come a great demand for iron nnd steel 

 and the vesr-el, held in place by a trip of some sort I steamers for our coasting trade; and with the uniform 

 or a plank bolted to sliding and ground ways, is re- j cheapening of iron in tho United States wo Khali, in 

 leased and slides into the water. The machinery is a few years, enter into competition with Great Brit- 

 then put in, and the vessel completed in evei-y re- nin and other European countries in ship-building 

 spect. The fittings of vessels are now very elaborate for the rest of the world. 



and costly. The drainage system of a large vessel is 

 fur more complicated than that of a house, as every- 

 one of the numerous compartments must be pumped 

 separately, 

 which tell 



A bounty bill is to be urged upon Congress pro- 

 viding for the payment, to sail or steam vessels en- 

 gaged in the foreign trade and built and owned 



if necessary. There are water-alarms wholly in the United States, of lit) cents per registered 

 when a compartment is leaking, and 'ton for each thousand miles sailed, and ]>><> rtitn fcr 



alarms to show when a dangerous temperature has any distance less than 1000 miles on any voyage bc- 

 been reached in the coal-bunkers. Provisions are tween this and any foreign country or countries. 

 made for exhausting foul air from below and for &up- This is excellent, so far as it goes, but our first ef- 

 forts should l)e to secure trade, to build up agencies 

 in eveiy large shipping centre where business conld 



bo secured for American vessels. Such a method of 



plying fresh air. 



Payments are made in various ways. In private 

 contracts there are various methods, instalments 

 being paid when certain portions of the work are payment would probably bring about vessels with an 

 completed, as when the first frame is raised. Under exaggerated tonnage measurement and, with econom- 

 government contracts the payments aro made in ten ie:il engines, the voyage would be the main thingand 

 instalments, with a reservation which, together with 

 the hist payment, is kcpta certain number of months 

 after the vessel has been turned to tho govern- 



the ports at the greatest distances and with the low- 

 est dues would be visited, and tho great object of all 

 an increased tonnage- would be lost. 



A better system, it seems, would be to pay "0 cents 

 per tun otfrei;/lit i-m-riivl, and there would then be the 

 take about two years in build ing tho former costing derided effort a to get freights and trade which are used 



nient. A 4000-ton merchant steamer is built in about 

 teu month*, while the same size man-of-war will 



about 8300,000 and the hitter 81,200,000. 



With a merchant vessel, when everything is com- 



Ce-t.-d, a run at full power is usually made for several 

 nirs, but with a man-of-war an official trial trip 

 must be made on which a guaranteed horse-power 

 or s|>eed mnst lie attained. As s|>eed is the object 

 to be attained in men-of-war of certain type,, it 

 wonld seem most natural to require a certain speed 



rather than a certain horse-power, though th.s is not of hull when of steel ami 10 when of iron, 

 always done. 



In beginning the design of a vessel, it is first nec- 

 e**ary to know tho conditions of service, the lo.id to 

 be carried, and the speed. It is known approximate- 

 ly what ratio the load will Ix-ar to tho Ural displace- 

 ment in the particular sendee, and, knowing tho total 

 volume of displacement, this volume must be en- 

 closed by a shape which will best attain tho t'iven 

 peed and suit the conditions of service and give 

 the required room. When what is known an a model 

 tank is available for experiments, a model is towed 



at home. Great Britain's vast 1 i :ide enables her mer- 

 chants to have agents in every poit, and Germany, by 

 sending men to offer her goods, is getting control of 

 what little trade we have in Africa. Europe's chenp 

 money is as much to be feared as her cheap labor, 

 and while we are helping the ship-owner we should 

 likewise help the shipbuilder, and pay 8500 per 

 'iwer "U the engines and $20 per ton weight 



In the preparation of the afcore article tho following publica- 

 tioufl ha v flraun fiom : Thr Xhijibutltlintf /</<j- 



; AV/'*/-:A <>ilti' ihi'ft "I'ttructvr oflht 

 A'ai't/ ; Htportt iiftkc Caiitmu*ivn< r oj .Va* iyativn. 



(L. .) 



SIIIULAW, WALTKB, artist, was born in Paisley, 

 Scotland, Aug. t>. !>->. and vias brought to tho 

 United States in 1HJO. He worked fora time as a bank- 

 note engraver, but later took up painting, exhibiting 

 first at the National Aeademv in isill. In 18C8 he \\an 



at various speeds, and the resistanceK obtained ; ami elected an aeailemician of the Chicago Academy, and 



from these the horse-powers required to drive the two years later lie ent t Munich, win re lie spent 



venae) at various speed* can be computed From these seven years in study. While there he painted the 



d*ta the engines are deaignwi. Engines can now be Toning of the Bell, and, Liter on, his best-known 



