278, On the Art of Hardening Copper, 
readinefs in cafting. All their inftruments and edged tools 
of this kind hitherto found have been caft, and not ham- 
mered; and of this kind, without doubt, were the inftru- 
ments mentioned by Profeffor Pallas as having been found 
near the Tfchudi mines. Al! of them, except a few, con- 
Alted of a compofition of copper and tin. 
The art of preparing and feparating i iron may have been 
difcovered as early as that of preparing other metals. As this 
art, however, requires a greater degree of dexterity, it was 
doubtlefs lefs common at firft, and muft have been diffufed’ 
more flowly, This muft have been the cafe much more 
with the art of preparing ftecl, which naturally would be 
much later than that of preparing iron, and melting tin and 
copper. The method of preparing fteel may have been ge- 
| nerally known in one country before it was communicated 
to another, where copper, hardened in the above manner, 
may have been ufed in its ftead. The Japanefe ftill ufe mir- 
rors of white copper, which confifts of a mixture of that me- 
tal and tin. The metal of the Chinefe gongs confifts of cop- 
per, mixed with 18 parts in a hundred of tin, and probably 
a little nickel ; and thefe inftruments are at the fame time 
fubjeted to ftrong hammering when cold. The Chinefe 
form their ill-fhaped razors of iron (not hammered) filed to 
an edge, and which cut fo badly, that, after every ftroke on 
the beard, they muft be drawn over a file. Many tribes 
who have been difcovered in modern times, and who are 
unacquainted with the ufe of metals, employ hard kinds of 
fiones for making knives, hammers, arrow-heads, axes, &c. 
Induftry always fupplies itfelf with its neceffaries, and em- 
loys for that purpofe fuch materials as can be obtained, 
without taking into account the degree of Jabour which the 
preparation of them may require. ? 
ine} 
rf : XII. Experi- 
