200. The metals are in some degree permanent, although several of them are employed in such forms that they are ultimately lost.
Copper is a metal of which a great proportion returns to use: a part of that employed in sheathing ships and covering houses is lost from corrosion; but the rest is generally remelted. Some is lost in small brass articles, and some is consumed in the formation of salts, Roman vitriol (sulphate of copper), verdigris (acetate of copper), and verditer.
Gold is wasted in gilding and in embroidering; but a portion of this is recovered by burning the old articles. Some portion is lost by the wear of gold, but, upon the whole, it possesses considerable permanence.
Iron. A proportion of this metal is wasted by oxidation, in small nails, in fine wire; by the wear of tools, and of the tire of wheels, and by the formation of some dyes: but much, both of cast- and of wrought-iron, returns to use.
Lead is wasted in great quantities. Some portion of that which is used in pipes and in sheets for covering roofs returns to the melting-pot; but large quantities are consumed in the form of small shot, or sometimes in that of musket balls, litharge, and red lead, for white and red paints, for glass-making, for glazing pottery, and for sugar of lead (acetate of lead).
Silver is rather a permanent metal. Some portion is consumed in the wear of coin, in that of silver plate, and a portion in silvering and embroidering.
Tin. The chief waste of this metal arises from tinned iron; some is lost in solder and in solutions for the dyers.
Chapter 17
Of Price as Measured by Money
201. The money price at which an article sells furnishes us with comparatively little information respecting its value, if we compare distant intervals of time and different countries; for gold and silver, in which price is usually measured, are themselves subject, like all other commodities, to changes in value; nor is there any standard to which these variations can be referred. The average price of a certain quality of different manufactured articles, or of raw produce, has been suggested as a standard; but a new difficulty then presents itself; for the improved methods of producing such articles render their money price extremely variable within very limited periods. The annexed table will afford a striking instance of this kind of change within a period of only twelve years.