74 
jBrass* 
they generally obtained 90 pounds of brass. Cramer re- 
commends 3 parts of powdered calamine to be mixed 
with an equal weight of charcoal dust and two parts of 
copper, and says, that the brass obtained by the process 
exceeds the weight of the copper by a fourth, or even a 
third part of its weight f At most of our English brass = 
works they use 45 pounds of copper to 60 pounds of ca- 
lamine for making ingot brass, and they seldom obtain 
less than sixty or more than seventy pounds of brass ; at 
Holywell they reckon the medium product to be 68 : and 
hence a ton of copper, by this operation, becomes rather 
more than a ton and an half of brass. This is a larger in- 
crease of weight in the copper, than is observed in any of 
the foreign manufactories that I have ever read of, and it 
may be attributed to two causes, to the superior excel- 
lence of our calamine, and to our using granulated cop- 
per. Postlethwayte, in his Commercial Dictionary, at- 
tributes the difference in the increase of weight acquired 
by the brass to the different natures of the coppers which 
are used, “ there is an increase of 48 or 50 pounds in an 
hundred, if copper of Hungary or Sweden be used ; that 
of Norway yields but 38, and that of Italy but 20.” When 
they make brass which is to be cast into plates, from 
which pans and kettles are to be made, and wire is to be 
drawn, they use calamine of the finest sort, and in a great- 
er proportion than when common brass is made, general- 
ly 56 pounds of calamine to 34 of copper. Old brass ! 
which has been frequently exposed to the action of fire, 
when mixed with the copper and calamine in the making 
of brass, renders the brass far more ductile and fitter for 
the making of fine wire than it would be without it ; but 
the German brass, particularly that made at Nuremberg f 
*Fleta Minor, by Sir J. Pettus, P.286. Newman gives the 
same proportions, P. 65. 
t Cram. Ars Doc. Vol. II. p. 246. 
