The boy's book of trades and the tools used in themAnonymous
General
The boy's book of trades and the tools used in them
Anonymous
Industrial arts -- Juvenile literature; Vocational guidance -- Juvenile literature
These heading tools are held, not by handles of their own, which would
break off with the concussion of the hammer, but by a sort of withe of
birch, or some other tree fastened loosely round them at their heads,
and bound by a ring to keep them from parting. The _punch_ is used in
making bolts or rivets, the _slice_ and _fire irons_ for arranging the
fuel in the furnace, and removing small articles after they are heated,
the _double hooks_ for removing or suspending bars, and for some other
purposes.
THE BRASSFOUNDER.
[Illustration: Casting.]
Next to iron, perhaps brass is the metal chiefly employed in the
manufacture of articles of daily use, and the trade of the Brassfounder
is therefore of very great importance, especially in connexion with the
small metal fittings, such as catches, locks, bolts, hooks, screws, and
other objects used in completing and furnishing the house.
Brass is not a pure metal, but is what is called an alloy, that is, a
mixture of various metals. It is composed of copper and zinc in such
proportions as may be necessary to obtain various degrees of hardness
and colour, according to the use for which the compound is to be
employed. The best proportions for common brass are about two parts of
copper to one part of zinc. Formerly brass was made by heating copper
with _calamine_ (which is the ore of zinc) and charcoal, but it is now
formed from melting the two metals together. It is then cast into plates,
which are either broken up for recasting into any required form, or
rolled into sheets. Common brass is very malleable, is more easily melted
than copper, and may be cast into any form. It will take a very high
polish, does not rust or tarnish by exposure to the air, and, although
it is durable in wear, is sufficiently soft to yield readily to the file
and other tools used by the workmen. These properties make it useful for
a great variety of purposes where steel or iron could not be so well
employed.
[Illustration: Crucible. Magnet.]
The smelting or mixing houses where the brass is made are fitted with air
furnaces, and in some of the best workshops the _crucibles_ or melting
pots are made of _plumbago_ or pure blacklead, which, although it is more
expensive, is much more durable than the Stourbridge clay, of which the
commoner crucibles are formed.
A very fine quality of brass for best castings consists of three parts
of best selected copper, and two of spelter, with some best scrap
brass and a little tin; while a second quality is formed of two parts
of ordinary copper and one part of spelter, melted into ingots with a
proportion of scrap brass and brass filings. Before the latter are used
the iron filings are separated from them by a _magnet_, or by a series of
magnets fastened to a revolving chain frame.
The sheet brass is procured from the mills where it is rolled, and the
brass wire is also supplied from the special manufactories where it is
drawn ready for use.
[Illustration: Making Moulds.]
Public-domain text, read in full here on John Shaqi.
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