mpounded?

_A._--Babbitt's patent lining metal for bushes has been largely employed in
the bushes of locomotive axles and other machinery: it is composed of 1 lb.
of copper, 1 lb. regulus of antimony, and 10 lbs. of tin, or other similar
proportions, the presence of tin being the only material condition. The
copper is first melted, then the antimony is added, with a small proportion
of tin-charcoal being strewed over the surface of the metal in the crucible
to prevent oxidation. The bush or article to be lined, having been cast
with a recess for the soft metal, is to be fitted to an iron mould, formed
of the shape and size of the bearing or journal, allowing a little in size
for the shrinkage. Drill a hole for the reception of the soft metal, say
1/2 to 3/4 inch diameter, wash the parts not to be tinned with a clay wash
to prevent the adhesion of the tin, wet the part to be tinned with alcohol,
and sprinkle fine sal-ammoniac upon it; heat the article until fumes arise
from the ammonia, and immerse it in a kettle of Banca tin, care being taken
to prevent oxidation. When sufficiently tinned, the bush should be soaked
in water, to take off any particles of ammonia that may remain upon it, as
the ammonia would cause the metal to blow. Wash with pipe clay, and dry;
then heat the bush to the melting point of tin, wipe it clean, and pour in
the metal, giving it sufficient head as it cools; the bush should then be
scoured with fine sand, to take off any dirt that may remain upon it, and
it is then fit for use. This metal wears for a longer time than ordinary
gun metal, and its use is attended with very little friction. If the
bearing heats, however, from the stopping of the oil hole or otherwise, the
metal will be melted out. A metallic grease, containing particles of tin in
the state of an impalpable powder, would probably be preferable to the
lining of metal just described.

718. _Q._--Can you state the composition of any other alloys that are used
in engine work?

_A._--The ordinary range of good yellow brass that files and turns well, is
about 4-1/2 to 9 ounces of zinc to the pound of copper. Flanges to stand
brazing may be made of copper 1 lb., zinc 1/2 oz., lead 3/8 oz. Brazing
solders when stated in the order of their hardness are:-three parts copper
and one part zinc (very hard), eight parts brass and one part zinc (hard),
six parts brass, one part tin, and one part zinc (soft); a very common
solder for iron, copper, a