april — sept. 1859.] Ancient and Modern times. 



93 



grains, quarters and eighths. The silver assay pound is divided 

 into 12 ounces, and each ounce into dwts. and half-dwts. 



In the French Mint silver is assayed " par voie humide.'' The 

 specimen is dissolved in nitric acid, and the silver precipitated in 

 the form of insoluble chloride by a standard solution of chloride of 

 sodium. From the precipitate the amount of pure silver present in 

 a given weight of the subject of experiment is easily found. The 

 presence of a little mercury impairs the accuracy of the result — 

 chloride of mercury, the result of decomposition of some of the 

 chloride of sodium, being also precipitated. However, the existence 

 of an appreciable quantity of mercury in the alloy is known by the 

 solution in nitric acid not becoming clearer when shaken ; and by 

 the first deposit of chloride of silver not blackening under the 

 influence of light. The addition of acitate of soda to the solu- 

 tion prevents the precipitation of the mercury. This method is 

 with proper precautions more accurate than the English ; but too 

 complex for an establishment where many assays have to be made 

 daily. 



An alloy of gold, silver, and copper may be analysed (if silver 

 be present in sufficient quantity) by dissolving the two latter me- 

 tals in nitric acid. The gold falls in a black powder and may be 

 fused into a button. The silver is then precipitated from the 

 compound solution by chloride of sodium or hydrochloric acid, 

 and the copper by iron. The assay of gold is more complicated 

 than that of silver, as it has first to undergo cupellation and then 

 the separation of the silver by nitric acid. 



An important subject connected with mint regulations is seig- 

 noeage — the duty sometimes paid to the State upon the conver- 

 sion of gold and silver bullion into coin. 



It is evident that a charge of this kind, whether only equiva- 

 lent to the actual expense of coinage, or in excess of this so as to 

 afford a revenue, adds to the value of the coin. The value of a 

 piece of money as of any other manufactured article is made up 

 of that of the raw material and the cost of manufacture. If there 

 is no seignorage, then, the coin passes for less than its real value. 

 The stamping in the mint adds to the Value of the bullion as " the 

 fashion to plate"— -to use Adam Smith's illustration ; with this 



