specific Gravity, and comparative Wear of Gold. 163 
fespect to abrasion, is produced under a less weight, yet it must 
be remembered, that the first case may occur.* 
Moreover, by the late experiments it has been proved, that 
fine gold, under all circumstances, is more subject to have any 
embossed or raised parts of its surface obliterated than any 
variety of alloyed gold; not always, nor indeed so much, by 
actual abrasion, as by having the protuberant parts pressed and 
rubbed into the mass, in consequence of its extreme softness and 
ductility .-f 
2dly. That fine gold, or of 23 car. 3^ grs. when rubbed 
against the various kinds of alloyed gold, always or generally 
suffers the greatest comparative loss. 
3dly. That gold reduced to 22 carats, or to standard, by silver, 
or by silver and copper, or merely by copper, suffers by friction, 
under general and similar circumstances, a smaller diminution 
than the fine gold abovementioned ; and, with or without abra- 
sion, the protuberant parts on the surfaces of these pieces remain 
* It is proper to remark, that the preceding experiments were made under a much 
greater weight than can be supposed to operate generally during the circulation of 
money ; and as, by some previous experiments, a less weight was found to produce, 
during a certain time, little or no effect, it may be suspected, that although, under a 
great pressure, fine or very ductile gold sustains a greater loss than some of those 
which are reduced to standard, yet, under a less pressure, or such as that which 
most commonly prevails in the course of the usual wear of coin, the reverse may pro- 
bably be the case ; for then the same causes operate with less rapidity, during a long 
period of time. From many various circumstances, there is reason therefore to believe, 
that the wear of coin against coin^f a similar quality is, under a small or very moderate 
weight, in the inverse ratio to the degree of ductility ; but this is only to be under- 
stood in the abovementioned case, of coin rubbed against coin of equal quality. 
f This is, however, of much consequence ; for, although coin may not suffer by 
actual abrasion, yet, if the impression made upon it can so soon be destroyed, it follows 
of course, that the pieces become (although still allowed to be current) no better than 
mere blanks, or fragments of a bar or ingot. 
Y 2 
