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236 MECHANICAL DENTISTRY AND METALLURGY.

smell somewhat similar to its taste. It is both malleable
and ductile, but excels in the former property, finer leaves
being obtained from it than wire. It is inferior to iron in
tenacity, but surpasses gold, sih'er. and platinum in this
respect.
The Fusing Point.—Copper fuses at about 2000° F.
Alloys of Copper.—Copper unites readily with most
metals, forming alloys of great practical value in the arts,
but which have but a limited application in dental labora-
tory processes. IMany of these alloys are curious and in-
structive, as illustrating the singular and unaccountable in-
fluence of alloying upon the distinctive properties of the
component metals. The followdng summary embraces the
names and composition of the more familiar alloys of cop-
per, omitting, as unnecessary in this connection, a descrip-
tion of their individual properties.
Alloys of Copper with Zinc.—Brass is an alloy of un-
certain and variable composition, consisting usually, how-
ever, of two to five parts of copper and one of zinc.
Prince's Metal, and its allied compounds. Pinchbeck, Sim-
ilor, and Manheim gold, consists of 100 parts of copper
and from 52 to 55 of zinc. Dutch gold, from which foil
of that name w^as formerly obtained, is formed of 11 parts
of copper wdth 2 of zinc.
Brass solder consists of about two parts of brass and one
of zinc to which a little tin is occasionally added.
Alloys of Copper with Tin.—Bell metal usually consists
of TOO parts of copper with from 60 to 63 parts of tin.
Cannon metal is compounded of go parts of copper with 10
of tin.
German silver is composed of copper, 40.4; nickel, 31.6;
zinc, 25.4; iron, 2.6; but the proportion of the metals of
this alloy differ according to the various uses to which this
compound is applied.