Brass . 
98 
is more malleable. This has been proved by experiment. 
Three plates of copper, equal to each other in surface and 
thickness, were exposed, for the same length of time, to a 
violent fire, with a view of seeing which would best sus- 
tain its action ; one plate was made of copper which had 
been purified by a chemical process, another was made 
of copper from Hungary, and the third of Swedish cop- 
per. The purified copper, when freed from the calcined 
scales, had lost 5 grains of its weight, that of Hungary 
had lost eight, and that of Sweden eleven grains. 
[4 Watson 3—69. 
This last experiment can be accounted for, inasmuch 
as copper is less oxydable than iron or lead or antimony, 
and therefore the purer it is the less apt it will be to scale 
off. T. C. 
Prince's Metal (Prince Rupert). This metal was pre- 
pared by Admiral Prince Rupert, in 1682. Three parts 
copper being melted and covered with charcoal, one part 
of zinc is added, and the vessel covered close. Or 8 parts 
brass being melted, one part of zinc is added with char- 
coal, and the vessel covered. 
Pinchbeck . — This is a redder metal, made by fusing 
one part of brass with one and a half or two parts of cop* 
per. 
Tombac.— Three and a half of copper to one and a 
half of brass. 
Or de Manheim. Similar . — -Marggraf melted pure zinc 
and pure copper together, in a great variety of proportions* 
and he found that eleven, or even twelve parts of copper 
being mixed with one part of zinc, (by putting the zinc 
into the copper when melted) gave a most beautiful and 
very malleable tombac or pinchbeck. Mr. Baume gives 
the following process for making a metal, which he says is 
called Or de Manheim , and which is used for imitating 
gold in a variety of toys, and also on lace s — Melt an ounce 
