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On the Art of Hardening Copper. 277 
may at leaft exprefs a with that fome perfon would make, 
of copper mixed in this manner with iron, different in- 
flruments, and then endeavour to fhew. real antique works 
made of the fame mixture, in order that they may be com- 
pared. Until this be accomplifhed, it will be beft to adhere 
to that procefs which feems to have been chiefly followed, 
and of which indubitable proofs are ftill in exiftence. 
The hiftory of the antiquity and ufe of metals in the period 
to which this queftion properly alludes, is involved in fo great 
darknefs, that nothing decifive on the prefent fubject can be 
derived from it. This much, however, is certain, that the 
works of ancient authors {till extant fpeak of gold, filver, 
copper, iron, tin, and Jead, as known at the fame time, 
and employed for various purpofes. In regard to copper in. 
particular, it is found more abundantly in a native ftate 
than any other metal, and requires nothing farther than 
{melting to be immediately ufed. In procefs of time man- 
kind would become acquainied with the art of extracting the 
metal from other ores of copper; not, however, without 
greater labour, and therefore at firft none but rich ore could 
be ufed; and we may with juftice conclude, that copper was 
one of the firft metals worked. 
Tin is not found in a native ftate, but its ore is abundant 
in certain places, and is eafily revived, or brought to the me- 
tallic ftate, efpecially when people are acquainted with the 
procefs of {melting other metals. The antiquity of tin, there, 
fore, is as well eftablifhed as that of the other metals among 
which it is named. In the time of the Tyrians a confider- 
able trade was carried on in this metal, which they brought 
from the Caffiterides iflands, beyond the pillars of Hercules, 
under which name England 1 is no doubt meant. 
Whether the art of mixing thefe two metals together by 
fufion was firft found out by accident, or by experiments 
made for the purpole, it is not tq be daubted that caft works 
of fauch a compofition are mentioned at. the fame period with 
the fimple metals. Befides, the works in bronze of the an- 
¢ients are a fufficient proof of their {kill in combining me- 
tals, of their art of modelling after Natyre, and of their 
readiness 
