Table of Contents

Title: Wrought iron : a short history of the development of the methods of production with examples of each stage of development
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00101119/00001
 Material Information
Title: Wrought iron : a short history of the development of the methods of production with examples of each stage of development
Physical Description: Book
Language: English
Creator: Pandula, Eugene
Publisher: Eugene Pandula
Place of Publication: Gainesville, Fla.
Publication Date: 1976
Copyright Date: 1976
Subject: Historic preservation
Wrought iron
Architecture -- Florida   ( lcsh )
Architecture -- Caribbean Area   ( lcsh )
 Record Information
Bibliographic ID: UF00101119
Volume ID: VID00001
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.

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Full Text
wrought iron

Introduction ............. .................... p. 1
General Information ....... ..................... P. 3
Early Methods of Manufacture................... p. 7
Primitive Methods of Manufacture............... p. 9
Early Egyptian Methods of Manufacture.......... p. 10
Asiatic Improvements of Manufacture............ p. 12
12 th Century Examples ........................ p. 14
Earliest European Methods of Manufacture....... p. 18
13 th Century Examples......................... p. 20
Double Stage Refining.......................... p. 23
Development of Pig Iron........................ p. 24
14 th Century Examples......................... p. 26
15 th Century Examples......................... p. 28
16 th Century Examples......................... p. 35
17 th Century Examples......................... p. 41
Puddling Process............................... p. 50
18 th Century Examples......................... p. 54
Derivation of Early American Wrought Iron...... p. 64
Mechanical Puddling Process.................... p. 85
19 th Century Examples......................... p. 87
20 th Century Examples......................... p. 92
Early Scientific Research...................... p. 95
Present Day Methods of Manufacturing........... p. 105
Characteristics of Wrought Iron................ p. 113
Quality Standards for Wrought Iron............. p. 120
Forging and Bending of Wrought Iron............. p. 128
Welding of Wrought Iron....................... p. 134
Specifications and Durability Testing.......... p. 138
Care of Wrought Iron........................... p. 144
Bibliography................................... p. 147
Sources for Photographs and Diagrams............. p. 151
Sources for Slides...................... ...... p. 154

page numbers 0

slide numbers 0


This report on Wrought Iron is meant to
give basic information on the processes
of production of the material and the
characteristics which the material exhibits.
It is necessary to know and understand
this information to effectively and
intelligently use the material. The
information is supplemented with pictures
of typical wrought iron products of certain
time and technological periods. The report
makes no attempt to follow the styles
and aesthetic changes of the material.

figure 1) wrought iron lock and key

"Thus at the flaming forge of life

Our fortunes must be wrought;

Thus on its sounding anvil shaped

FLAT Each burning deed and thought!"

U r 1 TS "The Village

figure 2) sign bracket, Oliver Cromwell
Inn, St. Ives

"The smith also sitting by the anvil, and
considering the iron work, the vapor of the
fire wasteth his flesh, and he fighteth
with the heat of the furnace; the noise
of the hammer and the anvil is ever in
his ears, and his eyes look still upon the
pattern of the thing that he maketh; he
setteth his mind to finish his work, and
watcheth to polish it perfectly.
Ecclesiasticus: 38,28

The Blacksmith -old song

Oh the blacksmith's a fine sturdy fellow,
Hard his hand but his heart's true and mellow,
See him stand there, his huge bellows blowing,
Fiery darts fall in showers all 'round
While the sledge on the anvil a-ringing
Fills the air with its loud clanging sound.

General Information

There is certainly at present something of a fashion
for decorative ironwork; that much may be deduced from the
many iron chairs, tables, reading-lamps, fire grates, fire
screens, and the host of other similar objects one sees
offered for sale in hardware and furniture shops. Although
they are all more or less expensively priced, attractively
painted and gilded, few of them manifest any appreciable
degree of true craftsmanship. If only the general public
knew a little of the history and technique of blacksmithery,
it would have no difficulty in perceiving the stamped-out
leaves, roughly finished scrolls, and crudely welded joints,
not only on such furnishings as these, but also on gates and
other architectural features where, for the sake of strength
and durability, a high degree of craftsmanship is absolutely
essential. With a little more knowledge and understanding to
contend with, the sham craftsman would be unable to sell his
goods so easily, and would be less of a menace to the true
blacksmith. Such ignorance is inexcusable when the craft of
the blacksmith has reached some of its highest peaks of
perfection, and where it has, even in the present age of
mass-production, persisted at an outstandingly high level,
albeit to a limited extent.

Before, however, the art can be properly appreciated,
it is essential that its material should be understood, for
it is this, raw iron, that helps to give the resultant work
so much of its character.

Iron is found in so many different forms and in
geological formations of so many vastly differing ages, that
many people consider it to be the most universally available
as well as the most useful of all the metals. Iron ore may
be found in any one of several conditions. The ore may be of
the carboniferous period, and if that is the case it will be
found interbedded with the seams of the very coal with which

it may ultimately be smelted; or it may be found on the still
beds of lakes, where it is even to-day being deposited.

When iron was first discovered by man it was credited
with having many strange and exotic properties. One of the
major reasons why iron was credited with magical powers is
that the metorites in which it was first found by man came
from the heavens and were (not unnaturally) thought to have
been flung thence by the gods. Its oldest (Sumerian) name,
in fact means "the stone of heaven". In those days it was
treated as a precious metal, as, quite apart from its
supposedly sacred origin, it was extremely rare.

There are several forms of iron, but that which is
generally associated with decorative ironwork, wrought iron,
is the purest form of the metal, consisting of 99.85 %
true iron. This purity is responsible for its most valuable
properties resistance to corrosion, ductility and toughness,
combined with great tensile strength. Such a combination of
virtues makes it invaluable for the blacksmith, for it is
sufficiently pliable for him to wreathe it into the most
delicate shapes, while it can also be rugged enough to stand
rough usage, and, although fibrous, pure enough to resist
normal corrosive influences. Little wonder that magical
properties were attributed by the ancients to such a metal!
So strong, in fact, was the belief in iron's supernatural
attributes, that it has forced itself down to us, even
today, for people still hang lucky horseshoes over their

It is difficult to say exactly when iron was first
smelted, as very few really early examples of blacksmithery
have survived the ravages of rust and time. There is
certainly not enough evidence to prove the existence of
a smelting industry.

The earliest method of smelting was probably discovered
by accident by some primitive man, who after having lighted

fires near ore-bearing rock, found iron in the ashes. From
this simple beginning were doubtless developed crude
smelting forges in the form of pits dug on the sides of
windy hills, with tunnels dug into them in which the wind
was trapped for draught.

The first smelting forge known to history, however,
was the air-bloomery. This, which was probably used by the
Romans in Britian, derives its name from the bloom of raw
metal which results from the process, and which was the
form in which the metal was eventually sold to the

Before the introduction of the machine age of the
nineteenth century there was very little difference in the
methods used to fashion wrought iron. The crude charcoal
methods that were used during the Middle Ages were still
in use. A hand-wrought nail recently picked up in the
Roman Forum, where some excavating had unearthed it, proved
upon comparison to be much like one taken from an old
house (built in 1724) in Wethersfield, Conn. In fact,
despite the difference of more than a thousand years in
their ages, they might well have been wrought by the same

**Cast iron is high in compressive strength but low
in tensile strength and, as a result, has little direct
use in construction.

**When pig iron is melted in such a way as to remove
nearly all of the carbon and other impurities, the result
is wrought iron. It is easily worked and welded and is
tough and ductile.

Before any art or craft can be fully appreciated
either historically, aesthetically, or mechanically, it
is essential to know something of its technique; but such
appreciation is made even more complete if that technique
is mastered. For the amateur or casual craftsman blacksmithery
is a difficult technique to acquire; for years of skill and
experience, coupled with much physical strength and
endurance, are necessary before it can be properly
assimilated. The work of the blacksmith is divided into
two main groups, namely forged work in which the iron is
worked hot at the anvil, and bench work in which it is
worked cold at the bench.


Early Methods of Manufacturing Wrought Iron

The manufacture of wrought iron is one of the oldest,
if not the oldest, branch of the ferrous metal industry, and
until recently the details concerning the methods employed
were not generally known. This was due to the fact that a
high degree of individual skill was required to produce a
good quality material. In many cases, the users of wrought
iron had very little reliable information on which to base
their decisions available to them.

Wrought iron is best described as a two-component
metal consisting of high purity iron and iron silicate
(an inert, non-rusting, glass-like slag). The two materials
are in a physical association, as contrasted to the
chemical or alloy relationship that usually exists between
the constituents of other metals.

During the thousands of years that wrought iron has
been made and used by man many different processes have
been employed in its manufacture. Naturally, vast improvements
have been made in manufacturing methods as well as in the
quality of the finished wrought iron. It may seem strange,
but, the characteristics of the metal and its metallurgical
principles used in production have remained unchanged. The
initial product, with any method of manufacture, which is
subsequently squeezed and rolled, is always made up of a
pasty or semi-fused mass of cohering, slag-coated granules
of refined iron.

The slag content of wrought iron, until comparatively
recent times, was considered as an undesirable impurity.
It was present because the maximum temperatures obtainable
in the furnaces used were not sufficiently high to keep
the iron in the molten or liquid state after the greater
portion of the metalloid impurities, principally carbon,
had been eliminated. Today it is recognized that slag is

responsible, in a large measure, for the desirable
properties of wrought iron, particularly its resistance
to corrosion and to fatigue.

In 1930, the American Society for Testing Materials
adopted the following definition of wrought irons "Wrought
Iron- A ferrous material, aggregated from a solidifying
mass of pasty particles of highly refined metallic iron,
with which, without subsequent fusion, is incorporated a
minutely and uniformly distributed quantity of slag"

Finished wrought iron has a content of iron silicate
or slag that varies from about 1% to 3%. The percentage
will vary depending upon the type of product that has been
produced. As an example, in the form of a pipe, the
percentage of silicate or slag will be about 3% of the
total weight. This constituent is distributed throughout
the iron base metal in the form of threads or fibres. These
slag fibres extend in the direction of rolling and are so
thoroughly distributed throughout the pure base metal that
there may be as many as 250,000 or more to each cross-
sectional square inch.

There are many ferrous metals, some are mentioned
later, but wrought iron is the only one of these that
contains the non-rusting slag fibres that give the material
its tough, fibrous characteristics.

Primitive Methods of Wrought Iron Manufacture

Iron was discovered and used long before man began
to record history. Man's first acquaintance with iron was
most likely the result of an accident that was caused by
the building of a fire on rocks and earth heavy in iron
ore. The use of iron really began when it was found that
the material could be easily forged into weapons that were
stronger than wood and tougher and stronger than stone.

For primitive man, the production of iron became a
matter of great importance and over a period of time he
more than likely learned to distinguish iron-bearing ore
from non-bearing earth. He then began to select the ore
that would produce the best and largest yield of iron and
build it into piles around his fires. Man then learned
that the metal could be produced more quickly if the larger
pieces of ore were broken down and mixed with the fuel.

Primitive Method _
figure 3) Primitive Method

Early Egyptian Methods of Manufacturing Wrought Iron

Although the origin of the forced draft in the refining
of iron is unknown, it is known that prior to 1500 B.C.
the Egyptians had developed a bellows that was operated
by having slaves tred upon the device which then expelled
air. The furnace which the Egyptians used was crude and
consisted simply of a hollow pit into which ore was dropped
upon blazing wood, yet the excellent grade of their wrought
iron is attested to by Egyptologists. These people, while
exploring old tombs, found on the doors wrought iron hasps
and nails that were as lustrous and as pliant as the day
on which they were made. There is evidence, and it is
believed, that the huge stones of the pyramids were cut
and fashioned by wrought iron tools made in crude forges.

FIG. i.'-Ground plan:
S..h A, The furnace, walls of .
large unburnt bricks, lined
'' with clay ; B, trench 3 ft.
deep, with sloping entrance, r '.
shown by arrow. FIG. 2. r "
v. .-Front elevation c, per-
Sorated plate of clay ;
E, E, plates or tiles of burnt .
S clay to fill space. FIG. 3.
Sd e . -Vertical section :G
figure 4) Early Egyptial mass of cow dung and A
chaff; i, hearth bottom of ra. _
Method sandstone or other hard G"
rock sloping towards front ;
w, clay wedge to regulate
dip of twyer. FIG. 4.- 1.-DIAGRAM OF AN INDIAN
The twyer, T, composed of FURNACE, FROM A MS. OF
two diverging earthen pipes MAJOR FRANKLIN.
embedded in a mass of (" Metallurgy," Percy.)
dried clay.
There are two bellows to a furnace fixed in front at a
convenient height. Twyer is kept in place by a vertical bar,
bottom of which presses on it, while top is hitched into a loop
of iron between two lateral studs or staples. Height of furnace
varies from 4ft. 4ins. to 8ft.; diameter at widest part from
aft. to 3ft. 9ins. Back of furnace inclines forward. This is
stated to be essential.

figure 5) Indian Furnace




figure 6) Indian Furnace

Asiatic Improvements of Wrought Iron Manufacture

The development of the original furnace is generally
credited to the Asiatics. It is also believed that the
Asiatics introduced the idea of adding layers of the ore
and fuel mixture at the top as reduction took place. The
early Asiatic furnace was such that it had a trough at the
top from which the smelter was able to rake fresh raw
material into the furnace. Bellows of improved design were
also employed. The heel of the workers foot (bare foot)
controlled the flow of air to the furnace. As he stepped
down on the bellows air was forced up into the fire
through a series of hollow bamboo sticks along the bottom
of the furnace. As the foot was lifted off of the bellows
the device refilled as the top was raised by a springy
bamboo rod. The refined iron accumulated at the bottom of
the furnace and when a sufficient amount was secured it
was taken from the furnace and forged.

Asiatic Method-Improved Furnace
figure 7) Asiatic Method


figure 8) The Iron Pillar of Delhi 912B.C.


figure 9) Hingework of door


figure 10) Hinge strap England


figure 11) Hinge Bands and Strapwork England

figure 12) Door Hinge England


VI - err ^ I I af ~'t *: E
;J^^U^^ 8^ ^. % gf

figure 13) Screen Door France O

figure 14) Door Furniture Spain 0


Earliest European Methods of Manufacturing Wrought Iron

The Catalan Forge was developed by natives of the
Pyrenies Mountains about 1293 A.D. and consisted of a furnace
two feet high with a forehearth or crucible about eleven inches
deep which was used to receive the heated lump of iron. It must
be remembered that this type of furnace could not produce
temperatures high enough to keep the metal in a molten state.
This resulted in the metal remaining in the form of a spongy
lump, which was then worked into specific shapes. The blast,
which was later derived from water power, entered the furnace
through tuyers which were about eleven inches from the bottom.
The efficiency of this new furnace was a decided improvement
over previous methods. This was due mainly to the charcoal fuel
used and the improved method of handling the air blast. The new
furnace could produce as much as 140 pounds of iron in five hours.
This type of furnace became widely adopted and with only a few
improvements was used as late as the latter part of the nineteenth
century to smelt the magnetic ores of Vermont, New Jersey and
New York.

)*^ h Century Improvement-Catalan Forge
figure 15) Catalan Forge g


figure 16) Catalan Forge


figure 17) Gate Detail France


figure 18) Door work England

figure 19) Grille Detail France


figure 20) Gate Detail -France


'- 4'* -

figure 21) Decorative Door Work
13th Century England

figure 22) Decorative door


figure 23) Panel Detail France

Double-Stage Refining Process of Wrought Iron

Until the fourteenth century the single-stage
reduction process was used with a great uncertainty and
with tremendous waste of time and material. This wasteful
and tedious method of producing wrought iron direct from
the ore began to be replaced by a division of the operation
into two stages.

It was fairly easy to rid the iron of manganese,
sulphur, phosphorus and other impurities. The hardest and
most uncertain part of the process was the elimination
of carbon from the iron because the charcoal used as fuel
was an eneraetic carburizing agent. It was only by the most
painstaking care that the wrought iron, when brought in
contact with this fuel, was prevented from recarburizing
to the point where it was no longer malleable and ductile.

It was discovered that by heating the metal a second
time it would be further refined, from its over-carburized
first stage, to a stage where it was not only more uniform but
also superior to the product of the single reduction
process. The second operation was carried out in a Catalan
type of furnace where the iron was refined further and a
portion of the slag was removed. This double refined mass
of wrought iron was termed the "blume" or flower, from
which the present use of the word "bloom" is derived.


The Development of Pig Iron in the Manufacture of Wrought Iron

Wrought iron was the only product made from iron
ore until the middle of the fourteenth century. About 1350
the iron makers of Central Europe developed a new type of
furnace. This development was in a large part due to efforts
to reduce the fuel consumption and the cost of manufacture by
increasing the size, especially the height, of the furnaces
being used to produce wrought iron. The product of this new
furnace was not, however, wrought iron because it was
removed from the furnace in a molten state, as contrasted
to the slag-impregnated sponge-like mass secured from the
furnaces or forges in which wrought iron was made. Also,
this new material, upon cooling, possessed certain properties
unlike those of wrought iron, due to the fact that it was
hard and brittle, and, when fractured, exhibited a crystalline
or granular structure which contrasted greatly to the tough,
fibrous structure of wrought iron.

The new furnace was known as a "stuckofen" and was
the progenitor of the modern blast furnace, and, like all
of the furnaces of the time and for some centuries later,
used charcoal for fuel. Raw materials which consisted of
iron ore, flux, and charcoal were added at the top of the
furnace while air, under very low pressure, was blown in
at the bottom of the furnace.

figure 24) Stuckofen Furnace

figure 25) Sweedish or Osmund Furnace

In 1619 Coke was first considered as a fuel, but it
did not really get any extensive use until around 1730. At
that time Darby successfully applied it to blast furnace
operation. The introduction of the hot blast followed in
the early 1800's.

The product of the stuckofen, or blast furnace, had
several poor characteristics, including its not being
malleable and ductile, its inability to be hammered or
forged and welded like wrought iron. It was soon discovered,
however, that the new metal could be cast into various
useful shapes. This was the introduction of cast iron.
From this, the principal product of the blast furnace
process became known as "pig iron" because it was cast in
small molds or "pigs". The pig iron, in this form, is
later remelted and used for the manufacture of other products.

The production of pig iron led to the development
of indirect methods for the manufacture of wrought iron.
It is not known at exactly what time pig Iron was first
used in the manufacture of wrought iron, but, in all
probability, it was employed to replace the product of
the initial step in the double-stage refining operations.
It is known for certain that the next major development
in the method of producing wrought iron, the Puddling
Process, was based on the use of pig iron as the raw material.

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figure 26) Door Detail France

figure 27) Door Detail France 0






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figure.28) Screen Italy 0



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figure 29) Door Austria


figure 30) Grating Austria

gure 31) Door Germany


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Nq 4-_!T

figure 32) Lock -France

figure 33) Lock France

figure 34) Door Germany

figure 36) Door Knocker Germany

figure 37) Door Knocker German;

l i re ) d ,m

figure ) Door ocer G e 4a.

figure 40) Door Knocker Germany

figure 41) Grating France

figure 42) Door Germany


'2' "-


figure 43) Door Knocker

figure 44) Door Knocker Italy


, !


figure 45) Door Knocker Italy




figure 46) Padlock


figure 47) Water Power Bellows

Ut -( Th-


figure 48) Keys -

igure 49) Door Knocker France 0

r rantt



figure 50) Grille Germany



t *

figure 51) Grille Germany

figure 52) Grate Italy

figure 53) Door Knocker Italy

figure 54) Grate Italy

figure 55) Grate Italy

figure 56) Gate France


figure 57) Window Grill Spain


figure 5

) Screen Czechoslovakia


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figure 59) Grill Denmark
.. .",a*

o j ,,--l n ^111i


i.-. 0) -g
fiur 60 ae England

figure 61) Chandelier Hanger

figure 62) Chandelier Hanger

'igure 64) Church Detail England

figure 63) Chandelier Hanger England


figure 65) Gates of Ham House England

figure 66) Hampton Court Palace England


figure 67) Staircase Balustrade England


figure 68) Grille France

figure 69) Gate Germany

The Puddling Process of Wrought Iron Manufacture

Although many minor changes were made from time to
time, the next major development in wrought iron manufacture
occurred in 1784. It was in that year that Henry Cort, an
Englishman, invented a new and radically different furnace
in which coal was used as the fuel instead of charcoal.
Cort described his invention as follows:
"For the preparing, manufacturing, and working of
iron from the ore, as well as from sow and pig metal, and
also from every other sort of cast iron, I make use of a
reverberatory or air furnace, the bottoms of which are
laid hollow or dished out so as to contain the metal when
in a fluid state."

The principal feature of Cort's furnace was that
the fuel was now burned on a grate adjacent to the bottom
where the iron was worked. All furnaces up to this time
had the fuel in direct contact with the metal which therefore
prohibited the use of coal as a fuel in the production of
wrought iron. The new furnace had the hot gases from the
burning coil pass over and fuse the charge of iron. This
had the effect of removing most of the impurities by

About 1830 Joseph Hall invented the Pig Boiling
Process which greatly improved Cort's original development
and used his reverberatory furnace for the new process.
During the refining operation it was necessary for the worker
to agitate constantly the molten pool or puddle of liquid
and iron slag. The tool that was used for this was known
as a rabble, and the process generally became known as the
"puddling process". This new process allowed the production
of wrought iron, in one plant, to increase from ten tons
per week to two hundred tons per week. The handling of
larger masses of iron with new and improved tools, methods,
and equipment produced wrought iron of a much better quality

than had been previously obtained.

The puddling process, as it is known today, parallels
the more general aspects of Cort's development of more than
a century ago. The most used furnace was simple, usually a
coal-fired reverberatory that sometimes had a waste heat
boiler in the stack. It was common in the Pittsburgh district
to use a single furnace, manned by two puddlers, and charged
with about six hundred pounds of pig iron. In the East
double furnaces were generally the rule. These were comprised
of two single furnaces placed back to back with the back
walls of each removed to make a single hearth. This situation
required four puddlers, two on each side, to work the charge.

The hearth of the puddling furnace, of either type,
had a cinder (iron oxide) bottom and was also lined with
plastic iron ore. The charge of cold pig iron was refined
to the desired wrought iron in about one and three-quarter
hours. The heat cycle consisted of several steps which began
with the pig iron being melted. Next, iron oxide, in the form
of roll scale, was added to the bath of molten metal and
thoroughly agitated by the puddler using a rabble. The
oxidizing reaction that follows, in addition to the basic
conditions maintained by the furnace lining, cause an almost
complete elimination of the carbon, silicon, sulphur,
phosphorus and manganese that were originally present in
the pig iron. The result is that the composition of the new
metal approaches that of virtually pure iron.

r8th Century Development-The Puddling
Furace figure 70) Puddling Furnace
.. .. .. ... .

The slag that was produced during the refining
reactions was an iron silicate, high in iron oxide ratio.
As the refining process progressed, it was necessary to
increase the fusion temperature of the metal bath due to
the reduction in the quantity of metalloids present. The
furnace temperature of about 2600 degrees F. was not enough
to maintain the metal in a liquid state, it was however hot
enough to keep the slag in a molten condition. For this
reason, it was necessary to carry out the finishing operations
with the metal in a solidified or pasty condition. Because of
both the reactions involved and the working by the puddler,
the metal took on the form of a spongy, plastic mass
impregnated with the liquid slag in which it was immersed.

When the refining operation was completed the cellular
or sponge-like mass of slag saturated iron was divided into
two or three portions each weighing two hundred to three
hundred pounds. Each of these portions was then formed into
a coherent ball which, at a welding heat, was taken out of
the furnace and put through a squeezer. The squeezer or
press caused the surplus slag to be ejected and formed the
metal into compact blooms. These blooms were immediately
rolled into rough, flat bar sections called "muck bar".
The muck bar was later sheared to short lengths which were
piled, reheated to a welding temperature, and rolled into
the desired shapes.

It was desirable for two reasons to include the "piling"
operation. First, it allowed a more uniform finished material
to be obtained, and second, it provided a mass of metal that
was sufficiently large enough to work properly into the
finished products. Uniformity is a very important aspect
of wrought iron production, and due to the fact that no
two puddlers could produce a finished material that was
chemically or physically the same, muck bar from several
different furnaces was used to make up the "pile". With
modern day techniques much larger masses of iron are
handled and accurate, scientific control over the manufacturing

operations has superseded the skill of the puddler.

Like all other methods used in the manufacture of quality
wrought iron, the puddling operation had as its object the
production of a coherent, sponge-like mass of highly
refined metallic iron. This mass would have incorporated
within it a quantity of siliceous slag. The sponge-ball,
as it is commonly called, is made up of many thousands of
small slag-coated particles of refined iron. In the pressing
and rolling operations that follow these are welded together
to form the finished material.

From the time it was introduced, until recently, the
hand-puddling process was the principle means used to supply
the worlds' requirements for wrought iron. The hand-puddling
process, however, had some serious limitations, especially
from the standpoint of quantity production and physical
uniformity of the finished product. Because of this, several
attempts were made to develop machines that would do the
same work that the puddler did in operating a hand-puddling


figure 71) Screen Austria



figure 73) Grille England

figure 74) Fanlight England

figure 76) Balustrade England


figure 77) Gates England ;[




gure 78) Sword Rest England



figure 79) Mace Stands England

figure 80) Suspension Rod for Chandelier
England 0

figure 81) Sword

figure 82) Sword


figure 83) Bracket France



figure 84) Bracket France


figure 85) Screen Germany 0

figure 86) Gates Italy


figure 87) Railing Switzerland 0

Derivation of Early American Wrought Iron Designs

Strictly speaking, there is little if anything
in the field of early American wrought iron that one
might justly claim as being distinctly American, that
is, of being characteristically indigenous or novel in
design and execution. Before the discovery and colonization
of America by Europeans, the use of iron seems to have
been unknown to the Indians generally, though, those in
Mexico were using gold, silver, and copper. This is
doubtless due to the fact that iron, though most common,
is the most difficult of all metals to obtain in a state
fit for use; and the discovery of the method of working
it seems to have been posterior to the use of gold, silver,
and copper.

European traditions were transplanted to a new
environment, and custom was rarely deviated from save as
an exceptional occasion might require. The Dutch settlers
in New York, New Jersey, and elsewhere left their impress
on the household hardware of their time, and any one
familiar with the subject can find in most of the original
13 colonies duplicates of the handiwork of the contemporary
English smiths, A little exploring in the Pennsylvania
German towns will reveal many replicas of the art as found
in the German Palitinate of two or more centuries ago.

In northern New York, and in Vermont, New Hampshire,
and Maine one still sees an occasional reminder that this
district was originally under French Domination. Evidence
of the early French blacksmiths' work crop out here and
there in the form of a shapely old hinge, or in the
subtle turn or twist of an andiron or latch or other bit
of old wrought iron. Some interesting specimens have
recently been unearthed in the old fortifications of
both Crown Point (old Fort St. Frederic of the French,
built in 1731) and Ticonderoga (originally known as Fort
Carillon and Vaudreiul, built in 1755-56), The traditional

"Latin" lines of sixteenth and seventeenth century France
and Spain are everywhere evident, too, in the ironwork
of the Vieux Carre in old New Orleans.

Wrought Iron Door Hardware
Locally made, or imported from England

Whether forged by the colonial smith or the product
of English factories, nearly all of the early American
hardware was hand-wrought, so it is difficult to judge
from this general surface characteristic whether a specimen
was locally made or imported. There are little crudities,
or slight modifications in the working out of the designs,
however, that mark an article at once as having been
locally produced.

It is reasonable to assume that in the more isolated
and inland settlements much of the hardware was a local
product. But as early as 1684, in the Fort districts, at
least, hardware needs were evidently supplied by importations
from England, judging from the ledger entries and
advertisements of old colonial merchants. The accompanying
entry from the account book of Paul Revere is interesting
evidence not only of what was being handled at that time
by the importers, but also of the old names and prices
of the articles. Indeed, if they were only a trifle more
specific, or more of them could be examined, it might
be established that many a piece of old wrought iron
here-to-fore classed as one-hundred-per-cent American
was "made in England" after all.

All White and Black-Smiths in the City of New York are re-
quested to meet at the City Tavern Tomorrow Evening at 6
It will be remembered in this connection that a blacksmith isone who'
.works in iron with a forge, and that a whitesmith works inwhite metal (as
a tin or silversmith), or is a finisher or galvanizer of iron.


.*', 6/ 7 0o 7 . "-

S71 X Y

30 .7, /

d ra 3 //aVf 7"

S7/- 3 ", 7

Or Exchanged for Property in the Country, on advantageous
THAT well known Nail Manufactory and Smith Works, No.
22 Cl'erry street, now in compleat repair with tools and im-
plemnents sufficient to employ 28 workmen-These works are
S'so ivell known and established, that the proprietor may, with I:
..propriety assert that his nails have a more universal circula-
tiori than any others manufactured in America. Any person
S willing'to -purchase the above works, and employ the hands
,. no 'at-worlk, will be enabled to keep up the credit of this
;', mmahufactory as is now established. And the subscriber as-
' ,_-sr-sures. thl':-ublic that the business bears a more flattering pros-
potth.an .:k' eyer has since its commencement.
s~ wishe's to enter in a line of business more retired is his .-
.! otive for disposing of the same. For further particulars .'.
'tl the fbscriber on the premises- O F TR .
". ,- "' ; ,". JACOB FOSTER. *
- p'"' ':' ,- "'" '- '* ' "! -"*" | '" ' ''

on following page

Old Anvils (typical)

figure 1

figure 2

Old Spanish anvil at Fort Marion, St. Augustine,
Florida. Believed to have been brought over
in the sixteenth century when the first followers
of Ponce deLeon settled there. This anvil
is reputed to be the oldest in the United

Early bicker-iron from the collection of
the Bucks County Historical Society, Doylestown,

Another eighteenth century "bickern"

figure 3

Old Anvils




'p. -
*1' p.

.4 V
'* fl p"'


4' a



,, ^ f':," '
>, .y *' '\ 2 h
~^ L*- ^.
'*< ^ ;?;A

figure 88)


on following page

Knockers (typical)

figure 1

From Funchal, Madeira

figures 2,3, and 4 Also from Madeira, and similar
in general lines to one from the old cloister
at Ephrata, Pa. and one on the Van Deusen
House. Here in the Portuguese possession the
hardware followed the traditional continental
lines as closely as in our own colonies.

figure 5

A scotch tirling-pin originally on Kellie
Castle, Scotland. This unique device, so far
as we have been able to ascertain, is a
peculiarly Caledonian invention and is rarely
found outside of the Scottish domain. Taking
hold of the "pin" and running it up and down
the twisted handle-grasp produces a racket
more than loud enough to notify those within
that a caller is at the door. There is a
possibility that one of these "knockers" may
come to light in the hills of North Carolina
where many Scotchmen settled in the early
days, so this specimen has been included
to aid in identification and comparison of
the future lucky find.



I.. -e
-xv /
& It

* C (i~
* '1

'I .i



figure 89)


U' .

on following page

Suffolk Latches Swordfish Type (typical)

figure 1

figure la

figure 2

figure 2a

figure 3

Swordfish latch on door of Nathan Hale Schoolhouse
in New London, Conn., @ 1774, similar to those
on Pocotopaug Tavern in East Hampton and
elsewhere. Thumb-press has some ornamentation,
but bar is much simpler.

Back-latch group of above. Bar is less ornate
than usual, and the bend in it near the catch
end seems strange. Perhaps it was so shaped
to fit a different jamb which may have been
altered during "restoration". The bar on the
Parson Russell House latch is bent similarly.

An attractive little specimen, similar to
figure 1 but much smaller over all, from
Colchester, Conn. Note the close resemblance
of thumb-presses, tooling of center handle,
shapely bar ends, and C.L. This latch probably
dates from early 1800, and has a sort of
dominating upper cusp.

Back members of figure 2. Bar is long, with
characteristic ornamental axis end.

A poor relation of figures 1 and 2 from
Marlboro, Conn., much simpler in design and
almost undecorated save at the center of
handle, Back latch missing. Thumb-press plain. C.L.


Suffolk Latches Swordfish Type

t' t

. ,

* /
I '






Is>. ~
~ r,.
ft L.
-, 3. -
- 'I. b
(9 '-'I.
K. ~


-~ 'A
~b ~-'


!**' 1


7 .. q ."-r.,,

,1 \jJ1 *' ,f ,

'4 4.
'-~ VA

figure 90)



on following page

Thumb-Presses or "Strikers" (typical)

figure 1












figure 13



Early form. Straight lift with very spare
grasp end. Notched type.

Straight lift. shaped, small grasp end. Notched type

Straight lift. Swivel. Ample grasp.

Short S.L. Notched type,

Curved lift. Notched pattern.

Curved lift, Notched pattern. Deerfield Suffolk latch

Straight lift. Pin joint. Neither notched or swivel

Curved lift, swivel, with formed grasp.

Curved lift. Novel.

Curved lift. Saucered thumb-press.

Curved lift. Drop curved thumb-press.

Curved lift. Extraordinary size, swivel with dished

Curved lift. Circular grasp. Notched. Flat-round

Curved lift. Swivel

Curved lift. Elongated and notched



Thumb-Presses or "Strikers" (typical) continued

figure 16 Curved lift. Swivel

figure 17 Curved lift. Very small notched type.

I Thumb-Presses or "Strikers"

-7 1'




r-'~ A3

.7. I


C, I

* >1

- I,

- ~- -I.
~' *~.

A 'A
-~ t -- -P.. -


-- 1~(->A.~1-;t--4t U

I,-' ,



~'y fi- a~ -~*~- -~ P
C C - ~ z...2......:


* 'it



~s I
.)Qj\ i

-9 --9-,' 3-. 9-~V1;
4 V ~ -,


.. cq.

C *tA- **1J"' -t it WA

15 ' 2. ?' -'~


figure 91)


T -'

Thu b r e or "

" ^ -T' '-. ^

on following page

Locks (typical

figure 1

figure 2

figure 3

Lock from old Crown Inn @ 1743, at Berhlehem
Pa. Probably the work of a local Moravian
smith, as the outlines of the escutcheon,
etc. are suggestive of the hardware handicraft
of that vicinity.

Lock of the old Spanish Treasury 1638, at
St. Augustine, Florida. A very good example
of the early wooden lock of simple form.

From the old State Treasury @ 1694-'-37 at
Annapolis, rMd., shows another lock of somewhat similar
type, with wrought iron binding. Locks of this
type were common to all the early settlements,
some of them heroic in size, particularly on
buildings of a public or semi-public character.


*~***" ,~'N
N, %



-. 4 42
*~'-~1'* ~f44. jilt

4. .44C*f-'*~ A-' I.

Id ~ '2
4' 4 -.

I ~* ~ *. 41
Ia ___ V ne---~ -.3 I

4* %4I.r' .~.
-S -.4.


* 4-
* i

.2 I-"

i4. .,







figure 92)



-7, '-, .

on following page

Lock Escutcheon Plates (typical)

figure 1 From the Moravian Museum, Nazareth, Pa., a
design quite similar to that of a latch from
Bethlehem, Pa.

figure 2 An eighteenth century escutcheon formerly in
Carpenters Hall, Philadelphia, but removed
in 1857 during alterations.

figure 3 From Bell House, Bethlehem, Pa. eighteenth century

figure 4 From Elder Brewsters chest brought over on
Mayflower in 1620 and now in Connecticut
Historical Society's Museum, Hartford, Conn.

figure 5 From Old San Miguel Mission, California,
eighteenth century. Drawn from sketch by Mr.
Hervey P. Clark, of Santa Barbara, Calif.

figure 6 From old church in Reading, Pa. late eighteenth
or early nineteenth century.

figure 7 Fine brass cockshead escutcheon owned by Mr.
Randolph R. Urich, of Myerstown, Pa., included
because of resemblance to pattern of figure 1
and interesting decoration.

figures 8,9 Old Pennsylvania escutcheons from the collection
of Mr, E. Zimmerman, of Monterey Pa.

figure 10 From Bethlehem Pa.

figure 11 Escutcheon from door of English Cathedral,
@ 1804, Quebec, Canada.


Lock Escutcheon Plates (typical) continued

figure 12

figure 13

Heart escutcheon from old Bronk House, Greene
County, New York.

Cockshead escutcheon recently unearthed from
the ruins of old Fort Ticonderoga, New York.
This piece, as well as others of characteristic
Pennsylvania German design found there, was
probably made by some of the Hessian contingent
of the British forces stationed at "Fort Ti"
in 1777.

Lock Escutcheon Plates


-, k C)

'4 7 -I
* 4

'N, <

-. N


L ~ 1)1,


Ii': N.

'4' '4

9. -4"' /
'N. /

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'- /',
K ^.'- -^

k. *1 \-

X* '*** "4
S *i

I" 'v
1 ? s

i^ ^

f... *^ A
v (A


4. '. ~J



-'I 9)

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/ 'N
.7 k, -



4'- A-


N ~

K. -

(~t )
o~ ~i\

K', _



figure 93)


' "'** *

on following page

Shutter Bolts (typical)

A group of Colonial shutter-bolts, giving an
idea of the variations in the form of pieces
of inside hardware. As one can readily imagine,
there was a great variety of these on the
churches and the more pretentious houses. It
is easy to believe that many of them were
imported,for some have all the appearances of
having been made in quantity.

figures 1,2 From the collection of Mr. W. E. Irving of
New York City.

figures 3,4 From Essex Institute, Salem, Mass.


N ~ii~

w<** ,. -,*



figure 94)


on following page

Cross-Garnet Hinges with pin joint (typical)

figure 1

figure 2

figure 3

An elaboration of the same motif as with
side member and pin joint. This handsome
hinge has birdhead finials suggestive of
the pelican, and is from the collection
of Mr. William B. Montague, of Norristown,
Pa. It is an excellent example of Pennsylvania
German craftsmanship.

Pewwdoor hinge of smaller dimensions, but
of similar general character, from the historic
old church founded by Muhlenburg in 1743,
Trappe, Pa.

Sketch of the pew-door showing placement of
these hinges (figure 2) and latch bar.


figure 95)

Mechanical Puddling Furnaces in the Manufacture of Wrought Iron

A furnace known as Danks Puddling Furnace was one of
the first mechanically operated furnaces which was used to
some extent in this country between the years 1868 and 1885.
The furnace was cylindrical in shape, and in order to
agitate the charge of metal, was rotated about a horizontal
axis. The furnace turned out to be a failure for several

James P. Roe, in 1905, invented the Roe Puddling
Furnace which was used by the Reading Iron Company of
Reading Pennsylvania. It was in production from about 1920
until 1938. The furnace itself was rectangular, twelve
feet wide and twenty-four feet long, and had a trough-like
bottom. To agitate the charge the furnace was oscillated through
various angles up to 120 degrees.

E.L. Ford of Youngstown Ohio invented the Ford
Process. The furnace was operated in an experimental
capacity for a number of years and was finally used on a
commercial basis in the early 1920's. This mechanical
furnace was similar to a Bessemer Furnace in both size and
shape and was rotated about a horizontal axis.

The Ely Process, patented by W.C. Ely of Terre Haute,
Indiana, and later purchased by the American Chain Company,
was adapted for the puddling of pig iron in about 1921.
The furnace was five feet square in cross section and six
feet in axial length. The structure of the furnace was
supported on two large carrier rings which were mounted
on power-driven rolls. This allowed the furnace to be
rotated or oscillated as required. Each heat, with a charge
of 750 to 800 pounds of molten pig iron, required about
35 minutes for completion.

H.D. Hibbard of Plainfield, New Jersey, invented the
Hibbard mechanical puddling furnace. The furnace was
essentially of the rotating barrel type and was first
operated on a commercial basis in 1921. The maximum
capacity of the furnace was about 1500 pounds of molten pig
iron which was worked into the finished product in a little
over 45 minutes.

The 200-300 pound Sponge Ball Produced in the Puddling Furnace

figure 96) Mechanical Puddling Process

on following page



figure 97) Balcony Charleston, South Carolina

figure 98) Gate Washington Square

figure 100) Balcony New Orleans

figure 99) Gate- East Bay
- ^^Bfl "^

figure 101) Balcony New
Orleans e

figure 102) Balcony Charleston, South Carolina

figure 1u3) balconyy en1iaaeipnia

ny Charl<
( ", '** *

% .0a

icony -tnur-n s,,v -,

figure 106) Balcony New Orleans

figure 107) Railing

figure 108) Balcony New Orleans

figure 109) Balcony Savannah, Georgia



figure 110) Balcony Charleston
South Carolina

figure 111) Balcony

figure 112) Balcony New Orleans:.

figure 113) Gates South

figure 114) Balcony Charleston
South Carolina

figure 116) Balcony Philadelphia

figure 117) Gate Charleston

^p-'^A& 1

figure 118) Balcony Philadelphia\.1

figure 119) Balcony New Orleans


figure 120) Fire Place Screen

figure 121) Fanlight
'-. ", '' ^ SS

figure 122) Fire Place Screen

figure 123) Fanlight

L vll


figure 124) Railing

figure 125) Railing @

figure 126) Railing !EW

Early Scientific Research in Wrought Iron Manufacture

From the time that the puddling process was introduced,
until recent times, it was the means used to supply the
world's requirements for wrought iron. In the late part of
the nineteenth century and during the early part of the
1900's some serious limitations were found in the puddling
process from the standpoint of quantity production and
physical uniformity of the finished product. These limitations
were found to be the cause of a number of efforts to place
the manufacture of wrought iron on a scientific basis. For
the most part, these efforts were un-successful because
the quality of iron produced in the puddling furnaces
was directly proportional to the quality of work that the
puddler was capable of, and beyond that skill no scientific
control was possible. This fact was subsequently discovered
through research.

Prior to 1915, almost all of the study done of
wrought iron concerned itself with the methods of production
rather than studying the material itself. Because of this,
it was believed that wrought iron consisted of "thousands
of fibres of pure iron, each coated with an oxidized slag
and each welded firmly to the other fibres". In some rare
instances this belief still exists.

In 1915 an exhaustive study of the material wrought
iron was started. Many samples of wrought iron, with known
records of service, were analized in the chemical laboratory
and studied under the microscope. From this it was learned
that the metal consisted of a matrix of high purity iron
in which thousands of threads or fibres of ferrous silicate
were embedded. Study with a microscope indicated that about
250,000 of the silicate fibres were contained in each cross-
sectional inch of good quality wrought iron. This contrasted
with the crystal-like structure of cast iron.

Wrought iron bars fractured to show the fibrous, hickory-like structure which is charac.
teristic of the material.

figure 127) Fractured Wrought Iron

Steel bars fractured to illustrate the crystalline or granular structure of the metal as con-
trasted with the fibrous structure of wrought iron.
figure 128) Fractured Cast Iron

It was also found that wrought irons, as produced by
hand methods, showed a great number of variations in chemical
composition. Due to previous beliefs and records of past
specimens, this. total lack of uniformity with respect to the
materials chemical make-up led to the conclusion that these
effects had no practical bearing on the durability of wrought
iron. This was believed to be true as long as the material
retained the characteristics of the purity of the base metal

and the embedded ferrous silicate fibres, which distinguish
it from all other metals.

The studies of old samples of wrought iron, which
have definitely established their durability under actual
service conditions, have been separated into four main
groups which are listed as follows.

group 1) Wrought irons containing normal phosphorus and
varying amounts of copper.
group 2) Wrought irons containing normal phosphorus and
no copper.
group 3) Wrought irons containing high phosphorus and
no copper.
group 4) Wrought irons containing high phosphorus and
varying amounts of copper.

In studying the tables of analysis it should be
kept in mind that the time period in which these wrought
irons were produced had a knowledge of chemistry and
metallurgy that was quite meager. At that time, very little
information of the chemical composition of ores was available
and the product of their reduction, pig iron, was classified
according to fracture. It just so happened that the chemical
content of the ore used was the chemical content of the
product, there was no further control.

This research on the structural characteristics and
chemical composition of good quality wrought iron resulted
in the basics for the development of present day manufacturing

Analyses of Wrought Iro


ns Containing Normal Phosphorus and No

C Mn P S Si Slag
.023 .026 .163 .023 .122 3.35

.o08 .070 .18o .022 .212 2.68

.044 .o059 .157 .014 .235 3.23

.030 .063 .146 .032 .202 6.22

.042 .015 .181 .010 .030 1.36

.038 .033 .18o .034 .197 3-97

.020 .022 .172 .020 .169 3.98

.0o36 .022 .152 .020 .16o 2.93

.019 .141 .145 .o025 178 3.16

Service Age


Cu. Service





1888 1934 46 16" suction line used in drydock
No. i at the Philadelphia Navy

1881 55 Wrought iron plate from loco-
motive watering tank owned.by
A. T. & S. F. R. R. at National
City, California.

1884 1931 47 /8" plate taken from the open,'
spill tanks serving the hydraulic
elevators in the old: Home In-
surance Bldg., Chicigo, which;
was razed in 1931.

1894 1934 40 11/4" pipe used as underground
gas service lines by the Public
Service Co. of Indiana at Tipton,
Indiana. .

figure 129

41 16" pipe line owned by the Pitts-
burgh & West Virginia Gas Co.,
located between Central, W. Va.,
and Littleton, W. Va. Now
operates under 140 lb. to 0oo lb.

1929 69 Wrought iron rail chair found
buried in wet clay soil along
Central of Georgia Rwy. tracks
about 40 miles east of Macon,
Ga. This type rail chair has
been obsolete since the Civil

44 4" wrought iron pipe (sample
No. i) taken from the lines be-
tween Titusville, Pa., and Mar-
cus Hook, Pa., laid by the U. S.
Pipe I.ine Co. In 1923 the old
pipe was sold to various other
companies and reinstalled.

1934 40 1/4" pipe taken from the orig-
inal heating system in the Cen-
tral Station Bldg., Chicago. Pipe
had been in continuous service.

1933 io8 Chain link taken from an old
chain suspension bridge across
the Lehigh River below Lehigh
Gap, Pa. Wrought iron link
still in good condition. Sample
No. i.

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