94 
Brass • 
and an half of copper, add to it three drams of zinc, cover 
Instantly the mixture with charcoal dust to prevent the 
calcination of the zinc ; this covering of the melted mass 
with charcoal is certainly serviceable in the way the au- 
thor mentions ; and it is on a similar principle, that when 
they melt steel at Sheffield they keep the surface of it co- 
vered with charcoal ; but I think it probable also, that the 
charcoal contributes to exalt the golden colour of the 
pinchbeck,. These yellow metals are seldom so mallea- 
ble as brass, on account of the zinc which is used in 
making them not being in so pure a state, as that is which 
Js combined with copper when brass is made ; yet it ap- 
pears from the experiments of Marggraf and Ban me be- 
fore mentioned, that when pure zinc and pure copper are 
used in proper proportions, very malleable brass may be 
made thereby. Mr. Emerson has a patent for making 
brass with zinc and copper, as I have been informed, and 
his brass is said to be more malleable, more beautiful, 
and of a colour more resembling gold than ordinary brass 
Is. It is quite free from knots or hard places, arising 
from iron, to which other brass is subject, and this quality, 
as it respects the magnetic needle, renders it of great im- 
portance in making compasses. [4 Watson 45—48. 
The last observation of Bishop Watson agrees with the 
experiments of M. Cavallo, who found almost all the spe- 
cimens of brass he tried, to be magnetic. The great in- 
convenience of this property, when the case of the com- 
pass is brass, is obvious, T. C. 
Mesure’s Metal Substitute for Gold, — Mr. Mesure 
of Craven-buildings, Drury-lane, having been, in conse- 
quence of the great scarcity and exorbitant price of gold, 
Induced to turn his attention to the discovery of a substi- 
tute for that metal, has at length announced the complete 
success of his exertions. The metal which is the result 
