CHAP. XXIII.
WEAR OF COItf.
169
experiments conducted under the direction of acommittee of the privy council 1 between 1798 and1802, by those eminent chemists Mr. Cavendish,since deceased, and Charles Hatchett , Esq., who,happily for himself and for all who know him, stillsurvives.
The object of those experiments was not ex-pressly for the purpose of ascertaining the loss ongold by abrasion in a given space of time; but toascertain what kinds of alloys and what proportionof those several alloys formed the mixture of me-tals which rendered them when coined into moneyleast liable to loss by abrasion. Mechanical con-trivances were adopted for rubbing against eachother pieces of metal of different proportions andkinds of alloys, and by comparison of their weightsbefore and after such rubbing, to determine whichdescription of them would form the metal leastsubject to loss for the future coinage of GreatBritain .
It was ascertained by the experiments of theseaccurate and acute philosophers, that gold of thefinest quantity that could be used, viz. that con-sisting of twenty-three parts and three quarters ofpure gold, and one quarter alloy, suffered a muchgreater loss by friction than our standard gold oftwenty-two parts in twenty-four of pure gold, and