the last Supplement we had occasion to speak of several
Birmingham manufacture in which brass or copper,
or some alloy intermediate between the two, is the material
on which the skill of the operator is displayed.
There are many more such, differing only in minor details of
working from these; but we may pass over them, and say a few
words on other matters.
Wire-drawing, or the manufacture of wire from rods of iron,
steel, or other metal, is extensively carried on at
Birmingham, and is a process illustrating in a remarkable
degree the ductility of metals. Unless a person has
actually witnessed the operations, there is some difficulty
in conceiving how the transformation takes place - how the
diameter of the rod lessens and the length increases.
There is no hammering or pressing or stamping, no cutting or
dividing, no moulding or casting; and perhaps this is almost
the only operation in the mechanical arts in which
alteration of shape is produced without any one of the above
At the Wire-Works of Messrs. Carpenter and Co., to which we
were favoured with access, the outline of the arrangements
is such as may be here briefly described.
The factory is situated in the western part of Birmingham,
and consists of several buildings, of which some are
occupied by wire-drawers, and the rest in a way afterwards
to be noticed. There is considerable power required in
the transformation of the iron rods into wire, and to
provide this force there is a steam-engine employed.
The other apparatus will come for notice as we proceed.
As nearly all wire is made pretty much in the same manner,
it will suffice to confine our attention to that made of
The iron is brought to the Works in coils of rods, wrought
to the state of what may perhaps be termed thick wire.
In the Supplement for February, while describing the
operations at a large Iron Works, we explained how iron is
brought into the form of rods and bars, by being drawn
between two heavy revolving rollers while in a white-hot
state. For wirework this drawing is conducted to a
greater extent than for most other purposes, until the
lengthened rod is thin enough to be twisted up into a coil,
and in that state to be transferred to the wire-factories.
The iron is covered with scale (the hard oxide produced by
the heat necessary to roll the rods) when it comes to the
Works; and to remove this scale the coils are put into large
revolving cylinders containing gravel and water, the
friction against which effects the desired object.
From these vessels the coils are taken to a large shop or
room where the whole apparatus is contained for reducing the
thickness of the metal.
Previously to describing these, it may be well to notice the
successive steps whereby the present system has been brought
Narrow filaments of metal have probably been employed for
various purposes from very early time; but Beckmann supposes
that, in the first instance, the metal was beaten with a
hammer into thin plates or leaves, that these leaves were
afterwards divided into small slips by a pair of shears or
some similar instrument, and that the slips were hammered
and riled to a tolerably round form.
Respecting the subsequent change in the mode of operation
Beckmann says, "As long as the work was prepared by the
hammer, the artists at Nuremberg were called wire-smiths;
but after the invention of the drawing-iron they were called
wiredrawer and wire-millers (Drahtzieher and Drahtmuhler).
Both these appellations occur in the history of Augsburg as
early as the year 1351, and in that of Nuremberg in 1369; so
that, according to the best information I have been able to
obtain, I must class the invention of the drawing-iron, or
proper wire-drawing, among those of the fourteenth century."
As respects our own country, it is supposed that all wire
was made by the hammer till about 1565, when some German
wire-drawers introduced an improved method. Even after the
improved plan of drawing the wire was adopted, the
preparatory processes were still very defective, for the
iron rods were brought to the requisite thickness by means
of the hammer.
To this succeeded a plan by which the rods were drawn
through a hole by sudden jerks, thereby reducing the
thickness and increasing the length. Lastly came the
improvement of passing the red-hot rods between grooved
rollers, until such a thickness is attained as to be fit for
the wire-drawer's operations; and in this state the art
remains at present.