The New Orleans bulletin. [volume] (New Orleans [La.]) 1874-1876, 1875-08-15
THE PITTsBURG OF THE SOUTH.
CHATTANOOGA, Tenn, Aug. IL, 49,

i CHATTANOOGA, Tenn, Aug. IL, 1875.
, Editor New Orleans Bulletin:
,, In my last letter I mentioned that blast
furnace and rolling mill were in full opera
ton here. Since then I have visited both
and so well pleased was I with what l saw
!, have concluded to give you the benefit of my
eyes. The blast-furnace is of very large size
is about eighty feet high, is constructed o
brick work, with great solidity, the interior
being lined with excellent friedrich, while
the exterior is covered with boiler iron tc
within about twelve feet of the base The in
side furnace is V-shaped from the bottom tc
about ten feet high; the remainder is of su-
gar-loaf shape, with the top squared off The
materlal-lime, coal, ore, etc.-is carried tC
the top of the furnace by means f two ele.
vators, one ascending while the other de-
scends.
There is valuable improvement over the
old style furnance, consisting of an iron pipe,
OF large dimensions, inserted near the upper
part Of the furnace, which extends downward
to the ground, and from there to the engine
room; in this pipe is collected the gas, which
IS now used as fuel for the engine, and to heat
| the air that is to be blown into the furnace.
The sole use of this splendid engine is to
blow-yes, to blow. the hot air into the fur
mace; and SO we'll does it perform its duty
that Immediately voted it the champion
blower, and this is good deal to say when
| call to mind some of our city blowers.
The use OF this furnace is to manufacture
iron, which is a most important industry. 1t
consists OF two distinct parts-frst, the pro-
duction from the ore, fusible carbonide of
iron; secondly, the decomposition of this
carbonide and its conversion into pure or
maleable iron. The clay iron ore is found in
the greatest abundance just across the river.
1t is mined, hauled and ferried by steam di-
rect to the furnace 1t is found associated
with coal, formed in thin beds, and consists
of ferrous carbonate, mixed with clay, some
times with lime and magnesia. 1t is broken
into pieces and carried direct to the furnace
above described. The old process of roasting
to drive off water and carbonic acid is dis
pensed with. q.
The aperture in the bottom of the furnace
being closed with wet clay, the fire lighted, it
is maintained by powerful artificial blast of
hot air, introduced by four twyere pipes,
around which continually circulate stream
OF cold water, to prevent the points of pipes
melting great improvement has been
made by blowing hot air instead of cold into
the furnace; this is effected by causing the
air, on leaving the blowing machine above
mentioned, to circulate through red hot iron
pipes until its temperature becomes high
mense saving in fuel, said fuel for heating this
air is the gas heretofore allowed to 90 to
waste.
The material, consisting of due proper
ton of coke, coal, iron ore ard limestone, are
constantly supplied from the top (Which is |
opened and closed by bell, by raising or |
lowering). The operation proceeds continu-
ously night and day. In the upper part of |
the furnace, where the temperature is still
very high, and where combustible gases
abound-whch are now saved aud used-the |
iron OF the ore is probably here reduced to
the metallic state. As the whole sinks down
and attains higher degree of heat, the iron
becomes converted into carbonide, while the
other minerals therein contained unite with
he lime, purposely added, to make kind of
glass or slag-nearly free from iron-lhe
ron and Stag in melted state, at last reach
he bottom OF the furnace, where they arrange
themselves in their order of density. The
Lag flows out at openings contrived for the
purpose, and the iron is discharged twice a
iay-morning and evening-and allowed to
un into rude molds Of sand by simply open
ng the orifice at the bottom of the furnace,
stopped with clay. And this is the
'rlgln of crude or cast iron Now, the con-
ersion of cast iron into bar iron is effected
hietiy by an operation called pudding; pre-
ious to which it undergoes process called
Ginning; it is remelted in contact with the
uel, in small furnaces called refineries, while
II is blown over the surface by means of
wyers. This process deprives the iron of
reat part of the carbon and silicum asso-
lated with it.
The metal thus purified is run into
rench and cooled. 1t is now white, crys ia
ne, very hard and called fine metal. The
uddling process is conducted in an ordinary
ay hut f11rn int nh; ab 81
introduced by side opening, speedily
lelted, and its surface covered with crust .
r oxide. The workmen then, by the aid of '
q iron tool, diligently stir the melted mass, il
, intimately mix the oxide with the metal,
ow and then throwing in little water, to b
lore rapidly promote oxidation; SIN all Jets of
lue flame soon appear on the surface of the
on, which now begins to lose its fuidity,
ad acquires first pasty, and then granular
ondition.
The fire is now strongly urged, the sandy .
articles once more cohere, and the contents
furnace are now formed into large balls or
asses and then withdrawn and placed
nder an immense hammer, driven by ma
linery, by which each is quickly fashioned D
to rude bar; this is reheated and passed
'tween grooved cast iron rollers and drawn
1t into long rods or bars; to make this into
llroad iron these bars are cut into number
pieces, piled and bound together, and
ain raised to white or welding heat, and T,
ssed back and forth through three sets
cast iron rollers, and lastly through
roller with groove or die, that fashions
d molds the railroad bar ready for the
IN horse. The bar is then placed on barrier
d drawn to two circular saws driven at
eat speed, and placed at proper distance H.
ar) where it is sawed off at both ends,
lille still red hot which operation ia indeed
autiful to see. The sparks, or iron saw NJ
st, thrown from ten to twenty feet in every
.ection, resemble myriads of the brightest
the spectacle is not equaled by any
eworks that it was ever my good luck to
hold. VIM. G. II.
t Will pay to buy your coffee, parched or
'und, at the Tea Depot, 5 Camp street.
!. DE KOYEN AND THE ILLINOIS q
BISHOPRIC.