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Catalan Steel Bloomery.

linsday catalog cover
•by Prof. M. W. Williams
Scientific American Supplement -
Sept 50, j876        sary in order
to flux away the silk this is done
Steel made directly from the iron
ore was the        at the expense
of the iron oxide one ore.
primitive method.. In the ancient
bloomerie5, where Here, then,
we have a miniature blast
furnace, pure oxides and
charcoal fires were used, most of
wherein the operation is stopped
at the reducing the iron
contained enough carbon to
come under zone, and the
spongy iron is taken• out before
the modern definition of mild
steel, and some of it        
absorption of impurities and
subsequent fusion
sufficient to form hard steel. 1t
was merely a matter        occ s.
Steel, or hard steely iron, is
usually and        y. of more or
less. blowing, and varying
proportions of mdWeasily
produced. In order to obtain soft
ore and fuel, whether. iron, semi-steel, mild or hard        a greater inclination is given to
the twyer, and the
steel was produced. The same is still the case with        blast is increased. A charge of 8
or 9 cwt. of ore,
the primitive iron workers of India, Burmah, Borneo,        containing 45 per cent of iron,
yields about 33 per
Africa, China, Madagascar, etc.                                               cent of iron ; and about
three tons of charcoal are
The Catalan, or Corsican; furnace, which is still                  used, for every ton of finished
iron produced. If the south of Europe,                                               this process were used in
England, with charcoal
especially in the neighbor- . at 50s. per ton, the cost of fuel alone would be £7
hood of the Pyrenees,                                                        I Os. per ton of iron, besides
very high charges for
demands some further                                                               labor.
description. It is shown                                                                 The American or
Canadian blbomery is similar.
in the diagram, where                                                 It is used in Vermont, Quebec, etc.,
but with a hot
f is the hearth, or fur-                                                                blast and a consumption of
about 1-3/4 of charcoal
,, --        nace, in which the ore is                                                       to 1 of finished iron.
~r<        reduced. The bottom of this is                                              The blowing
apparatus of the Catalan bloomer
.m                made of a sandstone capable                                       is a very Interesting
contrivance, It is called, the
of standinga great neat, and is . "trompe."                                         It is available in
mountainous countries
lined with a coating of charcoal                                          where streams: of water,
pouring from high levels,
;°        i,~14(        dust. A pile of ore - usually                                                are abundant.
An upper tank
rich hematite - is placed on                                                        is erected on a ledge of
rock, or other convenient
the hearth,. and heaped up                                                        place, with one end
overhanging, as shown in the
+7!        over the curved wall opposite        " diagram, where this end is. supported by a
the twyer ; and this portion        trunk. Connected with a large hole in ttie bottom is
is arranged to lie parallel to        a wooden tube with oblique openings in its she at
this curved wall. The hearth        b b. This tube connects wit lithe top of a lc wer'tank
y        is then filled up with charcoal        c, which has an outflow opening at d, and which at
and covered over with "greil-        its upper part communicates with th'e  twyer (made
lade," that is; charcoal dust        of copper) at e. This tank is otherwise closed and
and small ore moistened and        air-tight. At in the. Upper tank is a plug that can be
matted together. A gentle blast        raised and lowered by a lever to regulate the flood
is applied at first, andwhenthe        of water into the descending wooden tube.
flame bursts through the coat-        When the water is allowed to flow down this
tube, its velocity is of course
~        accelerated as it fiends.
Thisaccelerationdividesthe I~.        I ~f%/        column of water, and the
spaces between        r
~tastthere- ,~        `,II        ~l1        ~        fore become mor        ess
vacuous. In consequence
Mr        ~~
(        /        of this, air rushes in at b
.;r fr, b, and is dragged down bythe descending water;. and --ea`n not retYirn oft account
of the resistance offere
rj by the fallen and broken water, which enters the
'fir         — ''        lower tank by an opening
suddenly contracted by the
ing of greillade more is laid over it to check or damp the combustion; and prevent the
heap of ore piled over the curve from fallingin too soon. This is continued for about two
hours, then the blast is turned on fully, and the cinder tapped out. The ore that was piled
on the curved wallis-then pushed down gradually as the lower portion is reduced, and this
is continued until the whole sreduced and a mass of spongy iron formed. The bloom
e.._.        thus obtained is
then drawn out,
hammered, and
rolled with very
sndle        %i brassesa        primitive ma-
"x6Chro elwire~ chinery. Some unsfoirn^er        skilful manage-
IN EXPERIMENTAL PHYSICS, page Ap I        ment is neces-
there is a continual inflow of air as well as Water to the lower tank, and a consequent
pressure of air which produces a blast through the twyer. The pressure is regulated by
the quantity.,t water allowed to fall through from the u.ppet.tank, and may be increased
until it is so great as to overcome the falling water and drive itself back again up the tube.
When the inflow and outflow of water at the lower tank are equal, the blast remains steady
; when the inflow is in excess its pressure increases, when less it diminishes. One defect
of this arrangement, otherwise admirable, is that the air of the blast is supersaturated with
water, and even carries some spray. The ascending chamber at e allows much of the
spray to settle down before entering the twyer.
PO Box 538, Bradley IL 603 1 - 815/935-5353 - www,lindsaybifs..:com
it all
with these,
and an
antler tip
to chip and
These flint tools are
surprisingly sharp. Less than
12 atoms wide at the edge.
Sharper than the sharpest
steel edge. Fred, settle down.  
Are there Noah's
Bronze or Copper age.