Brass and Bronze.
So much similarity is observable in the modes of working in the different combinations of copper with other metals, that the same description will apply pretty accurately to all of them.
In brass founding and working, for instance, the making of the moulds, the melting of the metal in furnaces, the casting and subsequent trimming and finishing, the rolling into sheets, the drawing into wTire— all are conducted pretty nearly in the same way as for other metals. The making of
the brass itself is, however, rather a delicate operation.
This metal consists of about two parts of copper to one of zinc; the proportion not being exactly equal in all specimens. In the first place the copper is melted,
and poured into cold w ater, by which it is made to separate into small pieces varying from the size of a small shot
to that of a bean, and known as “ shot-
to redness in a furnace, reduced to a fine powder, and wrashed. Any quantity of the powdered calamine is then mixed with three-
earthen crucibles for several hours; at the end of which time the two kinds of metal have combined
together in a liquid state, and the charcoal has disappeared. The brass, formed by the union of the two
metals, is poured either into large fiat granite moulds, or
into smaller moulds of cast-
afterwards rolled into sheets or cast into small articles.
Sometimes brass is made by the direct union of zinc
and copper; but this is a more difficult process than
when calamine is employed instead of metallic zinc.
Bronze, like bell-
tin, but the proportions depend partly on the purposes to wffiich it is to be applied, and partly on the
opinions of the maker or artist. Bronze is a term frequently applied to the metal used for cannon, as wrell
as for statues ; and under this designation the French
founders are said to employ, for cannon, a ratio of
100 copper to 11 tin. Cymbals contain 78 copper to
1 22 tin ; medals, 100 copper to about 10 tin ; statues
; (on Mr. Westmacott’s plan), gun-
I cent, of pure copper added to it.
The mode of proceeding in casting a bronze statue is
much the same in principle as that of casting large bells,
but with greater precautions in every part of the operation. The making of the original model belongs to
| the highest department of art; for it is here that the
; sculptor show's his consummate skill, by imparting to
! the lifeless clay almost a living expression : all beyond
this, although requiring a very high degree of care, is
still mechanical, and governed by mechanical rules.
annoyance and disappointment. A t length his labours
seemed to be nearly at an end ; his mould wras lowered
into the pit, the furnace heated, and the metal thrown
in. A t this time, while a violent storm raged
without, the roof of his study, as if to increase the
confusion, caught fire; but, though ill and harassed,
lie.still directed the wrorks and encouraged his assistants, till overcome by anxiety and fatigue he retired
in a raging fever to lie down, leaving instructions
respecting the opening of the mouth of the furnace
and the running of the bronze. He had not, he
says, been reposing very long before one came
running to him to announce evil tidings : the metal
was melted, but would not run. H e jumped from
his bed, rushed to his studio like a madman, and
threatened the lives of his assistants, who, being
frightened, got out of his way, till one of them, to
appease him, desired him to give his orders, and they
wrould obey him at all risks. He commanded fresh
fuel to be throwm into the furnace; and presently, to
his satisfaction, the metal began to boil. Again, how7-
ever, it appeared thick and sluggish, and refused to
run. He then ordered all the plates, dishes, and
other articles of domestic use in his house to be brought
to him, which he threw pell-
it immediately became fluid, and the mould wras $pon
filled. Fie adds that he fell down on his knees, and
poured forth a fervent thanksgiving to Almighty
