r 506 ] 
Caftor and Pollux,, with ROMA In the exergue*- 
which weighs 81 grains. Another with the like 
imprefs on each fide, and V the. mark of the Qui- 
narius behind the head, which weighs 33 grains. 
A third in the fame page hath the mark XVI behind: 
the head of Roma, a biga on the reverfe, with 
ROMA in the exergue, which weighs but 54 
grains. As thefe pieces feem to be exhibited, chiefly 
on account of their uncommon weight, we muft fup- 
pofe the lightefc to be perfect. 
In the Britilh Mufeum is a coin like the tenth in. 
P. 3. Tab. 2. of the Pembroke Collection, which 
weighs above 73 grains. Another like the fecond in 
P. 3. Tab. 1 8, which weighs 66| grains; and a 
third, which feems perfeCl in all refpeCls, with the 
head of Roma and X on one fide, on the other a 
Quadriga with the infer! ption C N.G E, which weighs- 
but 55 grains. 
It is difficult to account for thefe differences in the- 
v/eight of the fame coin, efpeclally as Pliny feems to, 
have been ignorant of fuch inequalities ; for he tells 
us of anEaftern King, that wonderfully admired the- 
juftice of the Romans in coining all their Denarii of 
the fame weight, though the impreffes ffiewed them 
to be the money, of - different Emperors (5). Perhaps 
the King only admired the -invention of coining, 
which was not known in his country ; but Pliny, 
who tells the ftory, certainly fuppofed all the Denarii, 
were of equal weight. , 
Perhaps the heavy pieces of 73 and 81 grains . 
were ftruck at the mint for private perfons, to give 
(5) Pliny, Nat. Hift. L. VI. c. 22. 
. aw.iy>- 
