The Wheeling daily intelligencer. [volume] (Wheeling, W. Va.) 1865-1903, 1873-10-24

For the purpose Of obtaining the metal.
lie iron from the ore, ablast furnace Is
employed. They are usually from 40 TO
80 feet high, and IA TO II feet in diameter
tits cylindrical In form, diminishing in d.
ameter toward the Top and bottom. The
narrow portion at the bottom Is called the
cruei6e or hearth, and Is made Of very re-
iractory gritstone. In the front Of the
furnace is an inclined piece OF iron or
stone, 8 or 10 inches high, known as the
tymp-ir0n. Above this Is an opening for
the overflow Of the Stag. On both sides
and behind are openings for tuyeres or
blast pipes. At the lowest part Of the
furnace Is the tap hole, for drawing of the
melted metal at suitable intervals, and
which, except at such times, Is closed
with sand and clay. Above the crucible
the furnace suddenly iwidens, forming the
boshes, and above this sgain comes the
shalt. ".
The furnace is first heated with success
sive layers Of fuel and ore The burning
fuel is converted into carbonic oxide and
acid by the enormous quantity Of air
forced through the tuyeres, which Is not
less than 0 ions, or 1901 cubic feet, per
hour. Carbonic oxide Is q powerful re-
ducing agent, and this takes the oxygen
from The ore and forms carbonic acid.
The carbonic acid ascends. and in contact
with the red-hot coal loses half It's oxy-
gen and becomes carbonic oxide, which
10 turn takes tho oxygen from the next
layer Of ore, and so on. These hot gases,
on reaching the top, are no longer allowed
to escape, us formerly, but are conducted
of by large pipes, lone Of which is seen on
the LEFT Of the figure near the top), 10
ovens in the adjacent building, where
they serve 10 heat the air that is forced
through the tuyeres (hot blast To per-
nit OF the furnaces being charged at the
top without allowing the gases to escape,
IN improved arrangement called 0 "bell
and hopper" is used, as seen in the figure.
The ore and fuel are thrown into the hop.
per and rest on the bell, until, by
means OF lever, the bell Is slightly low
cred, and the materials are very evenly
distributed over the whole surface OF the
furnace. -- ~
The use Of the limestone or aux added
Is to unite with the silica, clay and other
impurities In the ore and form q readily
fusible glass called Stag As the meta
Is reduced and fused, 1t flows down into
the crucible, while the melted alag, being
lighter, floats on the top Of the iron, and
Is drawn of at q higher level than the
iron, The opening at the bottom Of the
furnace Is closed by an iron plate called
the dam, containing a coil through which
cold water continually flows TO prevent Il
burning up. The melted iron Is drawn
off twice day, morning and evening, and
Is q grand sight to witness, especially al
night. .m-ai III i-42
Cast iron, as it flows from the blast fur.
mace into the crude sand moulds, Is quite
impure, containing as much as ory5 per
cent Of carbon. 1t also contains little
silicon, and sometimes posphorus and sui
phur. II fuses at q white heat, and can
not be forged or welded. White cast iron
contains more carbon, Is harder, more
brittle and more fusible than gray. asa.
MALLEABLE Or BAR IRON.
To convert cast iron into malleable OF
bar iron, its carbon and other impurities
must be removed. These are burned out
In reverberatory or pudding furnace.
The details are nearly as follows: "The
crude pig iron Is first remelted and sud
denly cooled by which process II loses part
ofits carbon and silica, Is rendered white
crystalline and exceedingly hard. In this
state 1t Is known as fine metal II isnext
broken into fragments and introduced, In
charges Of 400 10 500 pounds, into kind
of reverberatory furnace, called'a pud-
ling furnace, and again melted. The
workmef, then, by means Of long iron
bars, stir up (puddle) the fused mass, and
thoroughly expose it TO the Influence Of
the heated air circulating above 1t. AS
the operation proceeds, the metal passes
from u liquid to pasty condition, emits
blue flames (carbonic oxide) gradually
grows tough and less plastic, and finally
becomes pulverulent Al this point the
heat IS raised TO the highest intensity and
the air Is carefully excluded by closing
the furnace. When the metal soltens sui.
iciently for The puddler to collect It IN
balls (called blooms) upon the end Of an
iron bar, II Is Withdrawn from the furnace
and placed under an immense steam ham.
mer, where the Stag containing the i'm
purities is hammered out II Is then roll.
ed into bars ready Tor market. -
Such ID briet and In popular terms the