The record-union., 1896-09-06

Otner, none are more useful than those
or copper with zinc, forming the differ
ent varieties of brass. This alloy ap-
pears to have been used when the world
was new-long before the silver ques-
Uon got before the people-and Lucre-
tius, one of those old-time Latins who
wrote books and died a pauper, bluntly
says that 1.-The use of brass was known
before that of iron" Pliny, too, who is
OFTEN wrong by the way, states that
Numa, the successor of RomuluS, who
is generally accredited with having
founded Rome, formed the workers of
brass into kind of community or COL
ony.
Scientists assert that long before zinc
was obtained as a distinct metal it's al
10y with copper was in use, the zinc ores
being reduced in process of making the
alloy by the charcoal mixed with them.
SO that when thus formed the metallic
zinc was absorbed in the copper placed
IN the crucible without once appearing
IN its own form.
Indeed, this process for the manufact-
ure Of brass was employed until 1871,
when James Emerson, the last OF the
Hlchemists, obtained a patent for MAX
tng 1t by a direct fusion of it's metallic
elements. Emerson's patent was
ringer" and his method, which was to
melt the metallic zinc and introduce
the copper in thin strips. is still en-
ployed. When enough copper had been
added to render the alloy difficult Of fu-
sion, the heat was increased and the ad-
dftional copper required was introduced
In the melted state.
;- f,
melt the copper first and introduce the
zinc with iron tongs, but the man who
first introduced the method failed to get
dis name on the patent right list, and
though he may have been worthy of
Better things, died at peace with him
self and unsung by the spring poet. The
process most used at the present time,
however, Is to place the copper and zinc
In alternate layers in fire-clay or graph
1te crucibles, and smelt them under a
thick layer of charcoal. When the fu-
sion Of the metals is complete the alloy
is cast into granite molds luted with
clay.
1t is extremely difficult to preserve
the proportions Of copper and zinc in
the manufacture of brass, owing to the
uncertain quantity Of zinc which es-
capes In consequence Of the high melt
ing points Of copper C2,200 degrees F.).
while the zinc becomes liquid at no de-
erees. Then. too, old brass is often
worked over, which further complicates
the estimation of the relative quantities
of the constituent parts. and the exact
composition of the metal is seldom
known except from analysis.
ut was ascertained years ago that the
best proportions to make fine brass was
two parts Of copper and one of zinc, and
that the quality of brass, as regards its
ductility, malleability and tenacity, va
Tied much according to the proportions
Of its ingredients.
Enough changes may be rung upon
the two metals-copper and zinc-to
make the ordinary professor Of legerde-
main turn green with envy. Thus, IL
copper sheets are exposed at a red heat
10 the vapors Of zinc. they are complete
1y penetrated by them and converted to
brass. Ingenious Frenchmen expose
copper rods to these vapors until the
surface is converted to brass, and then
draw them out into wire and put them
on the market as Lyons gold lace. Then
again, IL one place a copper coin in
crucible above mixture of zine oxide
and charcoal and heat it, it will become
brass without obliterating the device
And this is the metal used in the brass
foundry in the Southern Pacific Com
pany's shops In this city, and 1t Is here
that all brass castings, bearings Jour-
mails, ETC., are turned out preparatory to
being smoothed and polished, and often
plated in other of the departments
Brass, then, properly speaking, Is an
alloy of copper and zinc in varying
proportions, but the name is generally
applied TO all compositions of which
copper is the base, alloyed with tin
zinc or lead, and frequently all Of these
metals, in such proportions as to Sc
cure the desired result. Many castings
are made, however, that contain only
one metal-copper, lead or zinc. Four
parts Of copper alloyed with one part Of
tin, although both are very soft metals
makes the composition known as bell
metal, which is harder than cast iron,
and may be almost as easily broken
and by increasing the amount of tin
metal may be produced so hard and
brittle that it can be reduced to a pow
der Nine parts of tin and six of zinc
added to 100 parts OF copper make the
tenacious metal used for manufactur-
ing brass cannon.
In this department is made all brass
and bronze castings, car journal bear
ings. Rabbits and solder for the entire
Southern Pacific system, it's river and
ferry boats, and includes a wide range
OF work Within the last quarter of
century the construction of the big To-
comotiye marine and stationary en-
gine, the ponderous machinery of all
kinds. and the application of electri-
cal energy. have called for a compost
tion of greater strength and efficiency
with q minimum Of friction
The demand has been met by the in
PRODUCTION Of the phosphorus, magnesia.
aluminium and other bronzes which
have made a new era in brass found
ing. The ranges of combination of the
original ingredient had long ago been
reached. and while every shop had it's
own formulas for producing metals for
tts different kind of work, they all fell
short when great tensile strength, re-
sistance to heavy pressure and absence
of friction had to be combined in the
same casting. The chemical action OF
almost every known mineral has been
studied and experimental with In the
laboratory until combinations have
been effected that have doubled the
tensile strength and resistance, and de-
creased the friction of rapidly moving
machinery until the heating OF bear
ings. which has always been fruit
full source of trouble and delay. seldom
occur, and the expense OF repairs Is re-
duced to minimum
- In ha q a