specific Gravity , and comparative Wear of Gold. 133 
Table III. (continued.) 
Standard gold. 
Specific grav. 
Names of authors. 
Guineas, on a mean of seven 
trials upon those of dif- 
ferent reigns 
17,726 
Ellicot. 
A guinea 
17,629 
Brisson.* 
A piece of gold coin of the 
Commonwealth 
17,625 
Harris. 
Guineas, two new ones - 
174 H 
Hauksbee. 
Gold made standard by 
silver, in the ingot 
’ 7.92 7 
Hatchett. 
Gold made standard by 
equal parts of silver and 
copper, in the ingot - 
1 7.344 
Hatchett. 
Gold made standard by fine 
Swedish copper, in the ingot 
17^57 
Hatchett. 
* From the whole of the experiments related in this Paper, it must be evident, that 
small fractional variations in the specific gravity of gold coin do not merit attention ; 
it is not safe, therefore, to draw any general inference from a single experiment, 
made upon one piece, or even upon a small number of pieces. 
Mr. Brisson examined the specific gravity of a single guinea, which he found to be 
17,629; and, as he had previously ascertained the specific gravity of the gold coin of 
France to be 17,647, he says, “ this proves, (contrary to the received erroneous idea,) 
“ that the specific gravity of the French gold coin is greater than that of England.” 
Pe'santeur specifique des Corps, p. 9. 
But this conclusion of Mr. Brisson cannot be admitted; for, even the different 
proportions of silver and copper in the alloy, (exclusive of other causes,) may produce 
variations in the specific gravity of standard gold, between 17,927 and 17,157. 
