The Portland daily press., 1874-11-09
THE ES S.
MONDAY MORNING. NOV. 8. 1874.
THE FARM AND HOUSEHOLD.
Valuable Mechanical Receipts.

Valuable Mechanical Receipts.
Pinchbeck consists of copper, 5 lbs, zinc,
An imitation of silver is made of tin, 8 or.
copper, Abs. ..--.
Good Britannia metal consists Of tin, $50
lbs. copper, lbs. antimony, 1Olbs.
German silver of first quality, for casting
may be made of copper, 50lbs. I; zinc, 20 lbs.
nickel, best pulverized, 25 lbs.
To anneal steel, make the steel red hot,
then put it in heap of dry saw-dust till cold,
when it will be found to be quite soft.
For best red brass, for fine castings, take
copper, 24lbs.; zinc, 5 lbs,; bismuth, OF.
Put in the bismuth last before pouring off,
For black fux, take nitre, part; cream of
tartar, parts; mix and burn in small guam
titles in a red hot crucible; mix the product
with finely powdered charcoal; keep in a dry,
corked bottle. This is used in smelling me-
tallic ores.
To soften files, cover them with oil and
as soon as the flame runs all over the file,
plunge it in the water; or put them in
moderate hot oven for half an hour, if large
files; but, if small, the first plan is the best.
In metallurgy the following articles are
used as fluxes: Crude tartar, (if op a small
scale, commercial cream of tartar,) borax,
nitre, sal ammoniac, common salt, limestone,
glass, and fluor spar. These articles, being
easy to fuse, are added to substances which
are more refractory, to promote their fu-
sion.
To extract rust from steel, immerse the ar
ticle to be cleaned for few minutes, until
all dirt and rust is taken off. in strong So
luton of cyanide Of potassium-say about IL
oz.-in wine-glass full of water; take out
and clean 1t with a toothbrush, with some
paste composed of cyanide of potassium, cas-
tile soap, whiting, and water. These last
are mixed in paste about the consistency of
thick cream.
It is requisite that artists should have the
linseed oil they use perfectly colorless, or
otherwise it would spoil the most delicate
tints. To purify it is extremely easy. Even
putting bottle of the oil in the sun for some
days will accomplish the object: but, as this
process is somewhat tedious, it is better to
put in two ounce vial, three-quarters full of
good common linseed oil, piece of whiting
as big as nut, previously powdered, and
shake them together and put the vial in an
oven. In two days, and sometimes in few
hours, the whiting will have carried down to
the bottom all color and impurity, and the
refined oil floating at the top may be poured
off for use.
Boiled linseed-oil will keep polished tools
from rusting if it is allowed to dry on them.
Common sperm-oil will prevent from rusting
for short period. A coat of cOpal is fire.
quently applied to polish tools exposed to
the weather. Woolen materials are the best
for wrappers for metals. Iron and steel
goods of all descriptions are kept free from
the rust by the following: Dissolve half an
ounce of camphor in one pound of hogs lard,
take off the scum and mix as much black
lead as will give the mixture an iron color.
Iron and steel, and machinery of all kinds,
rubbed over with this mixture and left with
it for twenty-four hours, and then rubbed
with linen cloth, will keep clean for
months. If machinery is for expectation il
should be kept thickly coated with this dur.
ing the voyage.
Take pure copper, 100 parts; zinc, or pre-
| ferably tin, II parts; magnesia, parts: sal
ammoniac, 3.6 parts; quick-lime, 1.8 parts
tartar OF commerce, 8 parts. Copper is first
| melted, then the magnesia, sal-ammoniac,
| lime, and tartar, are then added, separately
and by degrees, in the form of powder; the
whole is now briskly stirred for about halt
an hour, so as to mix thoroughly, and the
zinc is added in small grains, by throwing il
on the surface, and stirring until it is entirely
fused; the crucible is then covered, and the
fusion maintained for about thirty-five min
utes. The surface is then skinned, and the
alloy is ready for casting. 1t has fine
| grain, is malleable, and takes splendid pol
ish. 1t does not corrode readily, and fol
many purposes is an excellent substitute fol
| gold. When tarnished, its brilliancy can bt
restored by little acidulated water.-West
ern Manufacturer.