1872.) Gold Coinage. 229 
design of St. George and the Dragon has again been restored 
to the sovereign. 
The last mechanical operation to which the finished coins 
are subjected is the weighing, which is performed by auto- 
matic balances devised by the late Mr. Cotton. It is impos- 
sible to describe these beautiful machines without the aid 
of diagrams; it will be sufficient to state that the coins are 
not only weighed, but are divided into three classes, the 
light, the heavy, and those which are either of standard 
weight or are within the ‘‘ remedy” or allowance permitted 
by law. 
Formerly the law directed that the ‘‘ remedy” should be 
on a pound weight of the coins, but the Coinage Act of 1870 
specified the actual legal weight of each individual coin, 
and rendered it necessary that each separate piece when 
issued, instead of each pound weight of pieces, should be 
within the limits of weight and fineness assigned to it: for 
instance, the weight of the sovereign is, as has been already 
stated, 123°2747 grs., and the variation permitted is 2-1oths 
of a grain above or below this weight. 
It will be evident that in aCtual working a considerably 
smaller ‘“‘ remedy” must be used in order to render it im- 
possible for a coin, the weight of which exceeds the 
prescribed limits, to pass into circulation. It will be evi- 
dent to all who are familiar with the small dimensions of a 
weight which represents the 1-1oth of a grain, that the at- 
tainment of accuracy in coinage must be attended with 
many difficulties. It is nevertheless the fact that the aggre- 
gate weight of the coins representing many millions in value 
does not exhibit a greater variation than I oz. from the 
exact standard. 
It must be remembered that the law also directs coins to 
be produced of an alloy the true composition of which is 
rigorously guarded; therefore the most important chemical 
operations of the Mint is the process of assaying. A piece 
of metal is first brought to the exact weight by cutting or 
filing : each weighed portion is then added to molten admix- 
tures of lead and silver contained in porous cups or ‘‘cupels” 
of phosphate of lime, which are arranged in rows in a 
muffle or small oven. The proportions of the latter metals 
are calculated so as to bear a definite relation to the sup- 
posed amount of gold and base metals present in the alloy. 
The lead oxidises and is absorbed by the porous “‘ cupel,” 
together with the copper and other oxidisable metals, and 
the silver and gold remain in the form of a button, which 
may also contain platinum, iridium, or metals possessing 
