A DANGER TO IRON SHIPS.

Grey River Argus, Volume XII, Issue 1281, 6 September 1872, Page 2

A DANGER TO IRON SHIPS.

[LIVERPOOL MAIL.] , r 'I f i We'tfi\ne8 f eaeyi that it is now fouba that the plating of tHoGlatton's bottom is again «« iriucn damaged from corrosion. • The action Baa not 'been- confined to the "former area „ ~ -near tb»atwn-poßt-and-ihH[mmediaU> yioxrspreaa over 6very part of the BUbme>*ge(t portion of the monitor's hull. Tho shelf-piece ,H lappbft&g^tbe'armoTed fafa round 1 til hull, the armor-plates resting noon the s shelfH'KlpfcWfCtho^JpTiftibg of tfe'fiull : bel6w the armored band, under the counters arid amiddiipaf(l|hO'frott ! '^Bb6ei^6T -prolongation of the keel supporting tho balanced rudder, the pbithig Hinder -the line of keef and the •—*Bpofor^« beak" pTojectiug-fronTthg'StSm aJ[ bear signs .Qfi -decay fromfsomo cause which bos power to destroy iron immersed in water. . 7 Near the two screws, but not on tho Uinmediate parts where the decay of the plating wai found-to have* occurred' whdn the ship was examined some months since at Chat- , ham, , the present damage appears to have . been concentrated more thau id other parts. «! Under the flat of the counter, and lrame- . ,} diately over the Bcrewal, there are innumer- ;, able spots of rust on each side inline with the throw of the screw. If these spots on rust are probed, the iron underneath is found to-bef pitted, lio the majority of instances, to 'ftLj^&j/i^f 6^ l^^ aQiinch. The » ' edges and' tiujler of tufl ' 'shoe l ' is nearly half an'iilqh thicKyfi'th.'iherust-mud, and] the iron proportionately' eaten away. Of - ihe port side of the shelf piece supporting the armorflhbstttl/fiA.'fcrlide with the centre - of the rodder, and therefore some feet abaft ( <t ; fan, mpwion Jtha¥/sldel "tLere'/iß* K \hw several inches in length deeply eaten' into' longitudipally with -the fibre 1 of the iron, nnd thia is also extending vertically into the - h'KWW^W ?f Ifearropcrpfct*'.. - M« the port 1 siae, nearly amidships, some nine or ten feet. below the wajier ,and,,^/no groat distance from the Kingston valve openings, the plating has been eaten into some depth in an oval form,' thi cetitre' of the plate hi the oval ■■" ' bciug iofir ynsrlMtlfiSfffm, \'he point of the '•prow" # prj|y;fteyiJiJWiafe<as> suffered extensively—in fact, it is gradually changing from V wrought ispn ,to the rust mndn Afltha de-._ ' feetive places as they are. found arS Feing carefully examined and stopped with cement, -...[Hi a( matter of coarse, and 1 the 1 cans* of the damage it-ia presumdd ia" fully understood ; but r iw?erjkhelew; there would: ' Appear to be several theories-held upon this subject. One ,-,. .oitheaefik that the watJßr«r"of the ; Medway, irom.sprae peculiar properties they are supposed to possess, are certain to net injuri- ;: oflaly ofl the bfltioras; ofallsirdfa SbipfAich lie in that river for auy length of Mine ; another -theory claim* for (tho cause of the; Glatkn s d image J;ho, .action of the/ pair of four-blftde* screws u'ppiitiie iron df'the ship's bottom ; while, another theory, ascribes j^t to local defects in the. iron itself. Of course it does not follow that any of the theories mentioned may^be correct., Metallurgista professors of chemistry may reply officially ,<.n.^thoroßghly tmderstood, that tU *imo thing has occurred boforo, and very Hkelv wiUpocnr again. Still tbefact remSnsth-t , the- plating of the Gktfcon is corroded to an exceptional extent, from a process to which other iron ships sue liable, that no means have yet been devised sufficiently efficacious to cheek it, and that unless science can far.

nish, the Required the time must come;wherthe vessel will be of no further use! ■ ' ' ' ' . ' ; ■• ■ ■ [Happily! science can furnish the required, remedy.' Useful inventions do not, as a/ule, emariato from learned or scientific men— more commonly from jthe practical hard-worker ; now, wo are, however, gratified to find that we have in Greymouth men who have patieUtlygrappled " with, and at length' sue-' cessfully overcome this difficulty, and have, reduced the effectual preservation of iron ships from rust to a dead certainty. The -fortunate possessors ~ofr this" secret* (Messrs* Stocks and Sherlock) in addition to this greatlj desired object, claim for their process the following, among other advantages, over any other at present known,- namely, an almost nominal cost when compared with other processes, economy in the time required, perfect immunity from marine vegetation or animalculre, and increase of speed, owing to the friction being reduced to a minimum, the hull always presenting a perfectly smooth and bright surface. We learn that the inventors are desirous of taking out a patent for their process, but unfortunately are not in a position to do so unaided ; they would, however, deal most liberally with any .juipitalißt who may appreciate the great iin'portance of the invention and its true commercial value in this age of iron steamers, ironclads, and iron ships.]