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¡Jways a mixlure of fulphur io il. 11,e olher fon, nn
Ihe cunlrary, is briule when cold, bUI lomcwhal duflile
wbm red·hol. This iroo is nOI folphonlcd, is natur2l–
Iyof a good qU¡JilY, and iu arifes (rom ¡IS me–
!allioe pans 001being (uBiciendy contpaaed logelher.
Iron abounds (o much, and is fo unire,f¡Jly diffufed
Ihrough Ihe earth, Ihal il is dilliCllIt 10 6..1a body io
",hich,here is oone al all: Aod Ihis halh led fevenl che–
milis inlo Ihe error of !hinkiog, lhal !hey had uanfmulcd
inlO iroo fewal fom of eartbs in which lhey fufpeaed
no iroo, by contbioing tbelll wilh an inBammable mauer j
",hereas, in faa, all !hey did was 10 give lhe mc,¡Jlioe
form 10 a lroe mani.1 eanb whicb happcned 10 be mix·
ed wilb otber eanbs.
r. " nl" Pig-iron antl 6rill/, [ron m~lItaUt.
Ino an canheo vcJfe! IL'Ídeniog upwuds, pOI fome
eharooal-du{l, and Ihereon lay Ihe pig·iroo whicb you
propofe 10 render dullile; cover il all over IL'Ílh a quan–
lity of charcoal; excile!he fire violeody IL'Ítb a pair, or
more, of perp~lual bcIlolVs liU Ibe iron me!l. If il do
nOI readily ftow and form a grral de¡J o( flag da its fur–
, add fome Box, foch as a very fuGble fand.
When Ihe mmer is in fufion, keep IIirring il from
time lO lime, lbal all Ihe pam !hereo( R1ay be equ¡Jly
¡aed 00 by Ihe air and lhe 6re. 00 !he forface o( Ihe
melted iron {miL IL'ÍII be fornted, whicb mu{l be takeo off
as !hey appcar. Al !he fame time you will fee a grra!
many fparklcs darted up from Ihe fumce of!he mel¡J,
whieh will form ~ fon of 6ery lbolVer. By degrees, as
Ihe iron grows porer, lbe oomber of I.befe fparkles di–
mioifhes, Ihough Ihey oever vanilb entire!y. Wheo bUI
few fparklcs appear, remove Ihe ccal! whicb corer Ihe
iron, and lel !he flag run OUI o( tbe velTel; whereopoo
me melal will grow folid io a momenl. Take il OUI
",hile il is mil red·hol, and give il a few Rrokes IL'Ílh a
hUlmer, 10 uy if il be doaUe. If il be 001yel mallea–
ble, repeal tbe op:rali90 afecoad time, io !he fame mao–
ner as before. L2fi1y, wbeo il is !hus fuJllciently puri–
fied by Ibe 6re, work il for a loog rime 00 Ihe anvil,.
eXlendiog il different ways, ani! makiog il red·hol as 0(–
len as !here is r.ccafioo. Iron !hos broughl Iu Ihe ne–
celTalY degree of dullilily, fo as 10 yield 10 Ihe hammel"
aod fuffer iúel( 10 be exlended every way, ei!her hOlor
cold, wi!houl brcaking 10 bits, er eveo cracking io Ihe
lean, is very good and very pore lf it =001be broughl
10 Ibis degree by Ihe melhod here prefcribed, il is a
proof, lbal Ibe ore flom whieh Ihis iron was eXlratled,
oughl 10 be mixed ,,'ilh .Iher ores; bOl il freq uenll. re·
quires a greal n-umber o( lrials lO obtain an exaa koow·
Icdge o( Ihe qualily and proportion o( !hofe olber orcs
wil~ whicb il is 10 be mixed.
r. cono,,' [ron inl. Slft/.
TAl t fm. 1I b~rs of Ibe bell iron; tllU is. of fach as is
malle~ble bolh hN and cold; fer Ihem 00 Iheir end, in
2 cylindrical earthcn vcJfel. "'hofe deplh i.s equ.llo Ihe
Icnglh of Ihe bars, aud in foeh a maoner Ihit Ihey may
be In inch rlillanl from each olher, and from Ihe fides
of Ihe crucible. Filllhe velfcl wilh a ceruent compound–
ed of IWO pans of charcoal, on pan o( booes burol in ;¡
s T R Y.
clofe ~dfcl lill Ihey become very Lbck, am! ooe half
p~rt of Ihe albes of greco wooJ; having 61a pulrelifed
and tboroughly mixed Ihe .. hole 10gelJ,u. care
10 lifl up Ihe iron ban a linle, 10 !he cnd Ihal Ibe te–
ment may cover Ihe bollom of Ihe vtfiel, and fo Ihal
!hm be aboul !he deplb o( balf ao incb !hercof uad"
every bu: Caver Ihe crocible .nd 10le on Ibe co\·er.
Sellhe crucible Ibus prepa eJ in a fomace, fo contri–
yed, Ihal Ihe crocibl. may be furrouuded 1L'Í!h coal, from
10p 10 bo 10m: Por eighl or leo hours keep up f, eh ~
degree of 6re Iba¡ !he relTeI may be moderalcly red; ¡j–
ler Ihi, taxe il 001 of Ibe furnace; plunge four liule
iron han inlo cold aler, aod you wil! find tbem con–
verted iOlo {Iecl.
Tbe prioÓj'¡J diffmnce belwccn iron and tlee! confins
in Ihis, Ihal !he Imer is combined wilh a grealer quan–
tilY of phlogiRon Ihan Ibe former.
It appem by tlli, experimenl, Ihal, 10 maxe iron unile
IL'Ílh an ioBammable mmer, il is necdTary il Iboald be
in fuuon; il is fufliciem Ih.1 il be fo red·hol as 10 be
opeoed .od foflened by Ihe 6re.
Erery kind of charcoal is 61 10 be an ingredienl in Ibe
oompo61ioo of the cemenl employed 10 make Reel, pro–
, ided il contain no vilriolic acid. Howerer, il hatb
beeo obferved, !hal anim¡J coals produce a fpeedier er–
fea Ihan olben: (or which rrafoo il is prop" lO mlx
fomelhiog of Ibal kind wilb chuco¡J-duR, as abore di–
leaed.
The follolL'Íng Ggns Ibew Ihal tbe operalion hub fue–
ceeded, and Ibat tbe iloo is ehanged inlo good {Ied.
This melal being quenehed in cold W2ler as propofed
above, acquires fi:eh an exlraoldinary degree of hard–
oé{s, Ihal il IL'ÍII by no meaos yicld 10 aoy impleffion of
Ibe 61e or hammer, and will foom break in pieces Ihao
{Irelch upoo lhe anvil. Aod hm il is proper 10 obfelT~,
lhal Ibe hardnefs of Ree! varies wilb Ihe maootr iDwhich
il is quenehed. The generu role i.s, Iba¡ Ibe homr
Ihe (Iecl i.s when qoenehed, and Ihe colder !he water is
in wbicb yoo queoch il, Ibe barder it becomes. It may
be deprived of Ibe lemper Ihus acqqired, by r.nakiog il
red-hot, and lettiog il cool 80wly; for il is Ihmbj'
foflened, rendered malleable, and Ihe 61e will bile upon
il. f or Ihi, reafon !he anifans who work io aee! begin
wilb unlempering il. Ihal tbey may IL'Ítb mOle raf~ fhape
il iOlo Ibe 1001 Ihey iOltod 10 make. The)' after...ard,
oew-Iemper Ihe 1001 wbeo 60ilbed. lnd bv Ihi.s fecond
lemper !he {Ieel recoven lhe fame degree of bardoefs il
bad acqaired by !he 6rfi lemper.
The colour o( lIeel is nOI fo white as Ihal of iron, bUI
darker, and the gr¡jus. faetts, or fibres, ",hich appcar
00 breaking il, are 6ner !hao Ihofe obferved io iroo.
1 ( Ihe bm o( iron !hu, cernentcd, in order 10 coorert
thent inlo Reel, be 100 Ihick, or nOI kepl long enough io
cemencalion. rhey ~ ill nN he turned inlo 11..1Ihroogh–
OUI Ihtir ",hale Ihickne(s: tllCir furfaces only will be
lIecllo acutain dcrlh, and Ihe centIC ,viII be mm iroo ;
becaofe me phloginon .... 11 nOI have thoroughly peoe·
tralcd IhL~n. On hreaking a bar o( Ihis fon, thc differ–
ence in. culour anJ grun buweeo Ihe {lee! and Ibe iroo is
very vifible.
It i.s eafy 10 deprire tlccl of Ibe fnpmhuodlol quanlity
oi