Q80 ON METAL3. 



sion to the throne. This must not be understood as if gun metal 

 was in her time made chit-fly of brass, for the term brass was 

 sometimes used to denote copper ; and sometimes a composition of 

 iron, copper, and calamine, was called brass ; and we at this day 

 commonly speak of brass cannon, though brass does not enter into 

 the composition used for the casting of cannon. Aldrovandus* 

 informs us, that 100 pounds weight of copper, with twelve of tin, 

 tnade gun. metal ; and that if, instead of twelve, twenty pounds 

 weight of tin was used, the metal became bell-metal. The work- 

 men were accustomed to call this composition metal, or bronze, 

 according as a greater or a less proportion of tin had been used. 

 Some individuals, he says, for the sake of cheapness, used brass 

 or lead instead of tin, and thus formed a kind of bronze for vari- 

 ous works. I do not know whether connoisseurs esteem the 

 metal, of which the ancients cast their statues, to be of a quality 

 superior to our modern bronze ; but if we should wish to imitate 

 the Romans in this point, Pliny has enabled us to do it ; for he 

 has told us, that the metnl for their statues, and for the plates on 

 which they engraved inscriptions, was composed in the following 

 manner. They first melted a quantity of copper; into the melted 

 copper they put a third of its weight of old copper, which had 

 been long in use ; to every hundred pounds weight of this mixture 

 they added twelve pounds and a half of a mixture, composed of 

 equal parts of lead and tin r . 



In Diego Ufano's Artillery, published in 1614, we have an ac- 

 count of the di tie rent metallic mixtures then used for the casting 

 of cannon, by the principal gun. founders in Europe. 



Copper . 160 100 100 100 parts. 



Tin . . 10 20 8 8 



Brass . . 8 5 5 



The best possible metallic mixture cannot be easily ascertained, as 

 various mixtures may answer equally well the rude purpose to 

 which ordnance is applied. Some mixtures, however, are unques- 

 tionably better adapted to this purpose than others, in some parti, 

 cular points. Of two metallic mixtures, which should be equally- 

 strong, the lightest would have the preference : at the last siege of 

 Prague, part of the ordnance of the besiegers was melted by the 



Aldrovandus, p. 10*. t Hist. Nat. L. XXXI V. S. XX, 



