182 Mr. Hatchett’s Experiments on the various Alloys , 
Table XIII. ( continued.) 
Quality. 
Weight be- 
fore friction. 
Weight after 
friction. 
Loss. 
Grains. 
Grains. 
Grains. 
Gold made standard by equal 
parts of fine and dollar cop- 
per, unstamped - 
24 5 ’ 9 ° 
218,10 
27,80 
Gold made standard by equal 
parts of fine and dollar cop- 
per, stamped 
247 , 3 ° 
2iq,.90 
27 , 4 ° 
Gold oi 18 carats, unstamped 
207,70 
■* 97 , 5 ° 
10,20 
Gold of 18 carats, stamped - 
208,70 
197,80 
lo.qo 
Standard silver, unstamped - 
146,20 
134,80 j 
1 1 ,40 
Standard silver, stamped 
144 
127,60 j 
16,40 
Fine copper, unstamped 
14 6,40 
133,80 ( 
12,60 
Fine copper, stamped 
164 
F 51 1 
13 
This experiment proves, that the difference of wear, thus 
produced upon pieces of gold which do not differ very consi- 
derably in comparative ductility, cannot easily be discovered, 
when the material or method employed to produce abrasion acts 
with violence and rapidity. 
For example, the difference of wear between fine gold and 
the various kinds of standard gold, appeared more evidently de- 
fined, when a soft powder like whiting was employed, and when 
the abrasion was very slow and gradual, than by the subsequent 
experiment with sand ; but, even in this case, the different and 
progressive effects became sufficiently apparent. On the con- 
trary, in this last experiment, with the iron filings, very little 
difference could be perceived, between the wear of fine gold and 
that of the various kinds of standard gold ; for, the rapid and 
