IRON.

709

w order to prevent the metal from running together as it softens, he removes it from thevicinity of the fire-bridge. When the whole of the fine metal has thus got reduceda pasty condition, he must lower the temperature of the furnace, to prevent it frombecoming more fluid. He closes the damper, takes out a portion of the fire, and theJibs of the grate, and also throws a little water sometimes on the semi-fused mass. Hethen works about with his paddle the dotty metal, which swells up, with the discharge°t gaseous oxyde of carbon, burning with a blue flame, as if the bath were on fire. Thehtetal becomes finer by degrees, and less fusible; or in the language of the workmen, itbegins to get dry. The disengagement of the oxyde of carbon diminishes, and soonstops. The workmen continue meanwhile to puddle the metal till the whole charge be■"educed to the state of incoherent sand; and at that time, the ribs of the grate arere Placed, the fire is restored, and the register is progressively opened up. With thedm?™ t * le heat, the particles of metal begin to agglutinate, the charge becomes moreatmcult to raise, or in the laborers 5 language, it works heavy. The refining is now■■■shed, and nothing remains but to gather the iron into balls. The founder with hisPaddle takes now a little lump of metal, as a nucleus, and makes it roll about on the^artaee of the furnace,- so as to collect more metal, and form a ball of about 60 or 70Pounds weight. With a kind of rake, called in England a dolly , and which he heats_ e jorehand, the workman sets this ball on that side of the furnace most exposed to thect *°n of the heat, in order to unite its different particles; which- he then squeezes3«her to force out the scoriae. When all the balls are fashioned, (they take abouti? niinutes work,) the small opening of the working door is closed with a brick, to causeJ heat to rise, and to facilitate the Velding, Each ball is then lifted out, either withbags, if roughing rollers are to be used, as in Wales , or with an iron rod welded to the■np as a handle, if the hammer is to be employed, as in Staffordshire . Thus we see■at the operation lasts in whole from 2 hours to 2j; in a quarter of an hour, the fineend ^ me * ts at its edges, when the puddling ljegins, in order to effect its division; at the,, a ®f an hour or an hour and a half, the metal is entirely reduced to a sand; a statet-iP 1S kept up for half an hour by continual stirring; and finally, the balling operation

hikes

uearly the same time.

—tuc saint; nine.

cutr ehar " e for ea ch operation is from 3J to 4 hundred weight; and sometimes thev , 3 s _°f bar-ends are introduced, which are puddled apart. The loss of iron is heresuff Vaiaa hle, according to the degree of skill in the workman, who by negligence maytorn er i • coas ’ < l er able body of iron to scorify or to flow into the hearth and raise the bot-

fcoali

^ Ju good working, the loss is from 8 to 10 per cent. In Wales , the consumption

are r est imated at one ton for every ton of fine metal. About five puddling furnacesPuddr lUlret * f° r the service of one smelting furnace and one finery. The hearth of the■Ronrt n ” ^ llrnacc should be exposed to heat for 12 hours before the work begins on therum,- a '*’ an '* 011 the Saturdays, the old sole must be cleared out, by melting it off, and11 °at by the floss-hole.

'vroimh • la fih a| R t obtained, in May, 1835, a patent <for the conversion of cast intoPotter 5 1 i UOn ’- ky adding a mixture of black oxyde of manganese, common salt, andfa r nace C " 5 ' n certa * u sma ll portions, successively, to the melting iron in the puddling

f nrn e ? Seating furnaces, balling furnaces, or mill furnaces, are analogous to the puddlinghut only of larger dimensions.

&c. tr V °°^ charcoal forge hearth is employed for working up scrap iron into boiler plate,tinn c ero ^ bushels of charcoal are consumed in making one ton of iron of that descrip-hoiler plate parings.

r n$.J lne \ f ? r f°. r S in S an d condensing the iron .—In England there are employed for the'hflerentp out °f the iron, cast-iron hammers of great weight, and cylinders ot

Powerfio l h mens i°as, for beating out the balls, or extending the iron into bars, as also^affordsh" earS " T^ese several mechanisms are moved either by a steam engine, as inthe local v™ 5 ant ^ ' n a ' most all the other counties of England, or bv water-wheels whenflff cvso"T? ) av .? favora Me, as in many establishments in South Wales . We shall hereTh e nj 6 ■ a ^ s concerning these machines.

cotnrnunic'T shaft usually carries at either end a large toothed wheel, which

these, the^ 6S 1Tla ^ oa the different machines through smaller toothed wheels. Ofand the two ^th eommon '5 r six, four of which drive four different systems of cylinders,'Vorlj should ° herS wor ^ the hammer and the shears. The different cylinders of an irona hd they mus? Cr ^ ace( * on the same arbor, because they are not to move together,haze time and p V -p’^ eient velocities, according to their diameter. In order to econo-chine the ham ac , ate labor, care is taken to associate on one side of the motive ma-f he several svstp 6 ^ p s ' 1 ? ar,? ’ and the reducing cylinders ; and on the other side to placeIhe Puddlin» furn 118 °‘ c l''nders l -01 " drawing out the iron into bars. For the same reason‘ai'naces on^the nii? es to he grouped on the side of the hammer; and the reheatingon tne other stde of the works.