New-York daily tribune. [volume] (New-York [N.Y.]) 1842-1866, 1856-09-16
MALLEABLE IRON.

From The Lond.a SATURDAY, P,,,~,
| When il was announced, at the late meef;,u.,
| British Association, that paper would h. sSs
| new method Of converting east into malIssS. =,
| without the use Of fuel, the intelligence W.
| by many with smile of ncrcdulity. and NJ
| "pratt teal men" went to the meeting Of Sea-
| expecting to be entertained by the visionary ~.
| of some Ingenious but idle enthus iast Tbe;v s~A
| tons were utterly falsitied. Conviction va ce
| upon minds from which no ready assent co,uSS
| been hoped; great invention was Iucidlv 49, n
tentatousy propoundcd; and mon who went 80.
for an exhibition of temerity If not Of clly. 49,
to express their concurrence in the graceful SSss y
admiration paid by Mr.. Nssmyth 10 one OF Ia ~.
est discoveries OF the age Every one felt H..
ing Mr. Bessemers paper that II any reliance ~,
be placed upon the facts stated to the Assorstjos.
new era at hand in all those numeso us and inns,
tant branches Of manufacturing industry which con
the working Of wrought iron and steel. Without f,rs
reference TO the paper communea TO the Assocst
we will now describe what we have seen al Mr. ~
ner's premises at Baxter House leaving readsns
say whether we have oyerstated the Importance A.
subject.
Ii is necessary TO premise that common css \,
contains somewhere about or per cent. Of csSs
as well as variable quantity Of scium and d.
earthly bases phosphorus and sulphur. The objea
every process for making malleabe iron lie the sepsR
ton and removal Of these foreign substances. n
best maleable iron contains about l per cect 4
cnrbon but the process of extraction is difficult n
expensive. The feasibility of iron depends upca
quantity of carbon present; and no rommercialyayS
able method has till now been discovered by whH
iron, after parting with very large proportion Oh
carbon can be brought to remain in state mn
nearly approaching fusion than that of pas'y ma
Steel il produced from iron from which the carbon *
other impurities have been extracted, bya tedious II
costly process the object OF which IL the rcstoratoa
portion of the carbon which previous processes h,s
removed. Steel contains, according Ia the puIos
for which it is wanted, from rather more than r
cent to rather less than per cent. of carbon. Ns
able iron-or iron comparatively free from carbcn-s
usually produced, in this country, in the followg
manner:
The melted iron a. extracted from the ore in d
smelling or blast furnace, is out into bars h
feet i'm length technically termed pigs. These pig
when cold are removed from the sand-mol,ls ms
which they were rum and transferred to second fr
mace called the iDing furnace, where they are agsn
reduced TO state of fusion; and finally, the tins
produced is placed in third furnace where II undes
goes the process of pudding Omittng all matter d
detail the essential part of this operation is the redae
ton of the iron TO pasty mass which IL stirred anil
rolled about by the workman until a large ball o.
"boom" of iron, weighing from % to ~ pouInls b
conglomeraed at the end of the rod with which BE-
works and is Judged 10 be in Tit state tor the hnl
process. 1t is then withdrawn from the fire, and tak
10 " fitting hammer" and pair Of squeezers,
TO Nasmyths steam forge, where it Is Subjected
TO a very heavy pressure, and q quantay
melted Stag and refuse, mixed with the padded
iron, squeezed out. For the purpose of our preeens
comparison We need follow the process no fartl@.
Other methods of producing maeable iron directly
from the ore are in in various parts OF the Conf
nept; but they are extremely expensive, require nca
ore and very pure fuel, are only applicable upon
small scale and sacrifice very large percentage
some eases from 40 to 50 per cent-of the metal
OF all our more important mechanical operation
perhaps pudding is the most imperfect and unsatisfs
tory Ii is very expensive, both from the quantity Of
fuel consumed (which is about equal to the weight
metal treated and the severe nature Of the labor ~
49, hot. fl..rs tsunI
necessary to stop nearly all the Stsordshhe pwidas
funaces-two men having fallen dead at their work
The result is the production OF an iron 30 tar from be
chemically pure that it il astonishing how much We
have.sbe able Ia effect with 50 imperfect mascn1
From the immense demand for iron which has pre-
vailed for some years past and the stimulus tmt No
thus been given to the production OF increased
f;ty the quality has very seriously deterioraed. Ik
difficulty experienced by the Government during Tie
last war in procuring iron OF quality suitable for II
purposes of warfare ia too well known 10 need nor
than passing reference. .t
Mr.. Bessemers experiments have been conducts
upon the pig-iron He proposes that for the pmpcx
OF manufacture the smelted ron II leaves the sM
furnace shall be run Immediately into the converilE
vessel presently to be describcd but for the pupos
of experiment, it has been more convenient ID me-
down pig-iron as the metal is much sooner reduceds
state Of fusion The experiment. therefore, takes "
the process at the point at which the metal Is ordinary
placed in the fning furnace IL must he remembers
however that one impOrtantend answered ny his 'nvs
ton is do away with the consumption OF fuel rcqu
for this intermediate process. The converting vessel
where the change Of the melted metal from or'ina1
east iron 10 malleable iron steel In to take place
consists EXIT rnaly, OF cylinder of iron, surrounded
near the bottom, by hollow ring-an annular pipe
In fact-Of the Same metal communicating with nv,
small "tuyere" pipes placed at equal distances rouni
the cylinder. These pipes are can-iei ihrougo
the outer and inner structure VI the vesee, aud ee
of them enters the chamber within near the junction
of the side with the floor, by aperture aboH three
egbths Of inch in diameter, protected by cos,n
Of the best ire-clay. The external cylinder Is toed
It'll thick lining of friedrich, and the internal strsc
ture consists of two chambers or Stories cOnmunlcs
ing by small cylindrical opening in the center. IN
lower chamber, into which the melted iron h intro
duced, is simple cylinder-be upper chamber has
floor inversey arched that any melted metal ioree'
up through the opening from the lower chamber ma
tckle back sgain, and the roof Is ia the shape Of
cupola or dome Two apcrturcs. few inches square
placed opposite 70 cnch other, between the floor an
The ton ofthis Chamber communicate with the oxterns
air. power iu blast worked by small engine, ca
be let into fLo hollow ring which girds the outer sylI
der and thence of course, enters the lower chambe
through the tIyoYc pipes hole Mt the bottom Of tli
chamber secured in the usual manner, furnishes tn
means Of tapping the vessel aud running OIL the prOuc
into the mods prepared for II.
When everyihing is ready for the operations 4
commence the blast il set on b. blow into the convert
ing vessel-tbe melting furnace il tapped-apd the
melted iron OF the usual deep orange tint pous slowly
down the channel into the lower chamber of the con
yerting vessel through an aperture which is the
closed up and luted. The pressure of the blast
about OF 10 pondsto the square inch-s'rong enouf
to force the all completely through the suporincuu
bcnt mass Of fused iron, and ont through the aperla
near tie top of the vessel As the action Is continued
every particle ofhe melted metal is brought in tun
into contact with stream Of air. To use the langus
of chemistry, energetic combination taxes place
tween the oxygen of the air pumped in and the ssr
Ion mixed with the iron In popular language, fire
stead of being supplied externally round and about u
ass of ron kndIed and sustained throughout eve9
particle Of the liquid metal heat is thus generated
vastly greater than that which be supplied BY nS
external combustion. What is taking place indicss
by the tongues Of fame which in two three nnnase