862 
Tin. 
upon the tin, and plunged to the bottom by means of an iron 
instrument resembling a wheel, with a long handle fixed 
in the axle. A violent ebullition is immediately excited, 
and a little slag, which was before mixed with the metal, 
rises to its surface, and is scummed olf. In a minute or 
two after, the metal is tried, by taking up a ladleful and 
pouring again into the mass, when if it appears quite 
bright like silver, and of an uniform consistence, the pu- 
rification is complete, and nothing more is requisite than 
to cool it to a proper degree, and lade it into the moulds, 
by which it is formed into pigs, weighing from two to 
three hundred weight each. If the metal is poured too hot 
into the moulds, it is apt to be brittle. Good stream-tin 
affords from 65 to 75 per cent, of the very best and purest 
grain tin. 
None of the Cornish tin may be sold till it has been 
coined ; for this purpose a small piece is cut off from eve- 
ry pig and assyed ; if it appears of the requisite purity, it 
receives the stamp of the Duchy, and pays to the Prince of 
Wales, as Duke, four shillings per cwt. 
Tin is a metal of a yellowish white colour, considerably 
harder than lead, scarcely at all sonorous, very malleable, 
though not very tenacious. Wires cannot be made of it ; but 
under the hammer it is extended into the leaves, called tin 
foil, which are about one thousandth of an inch thick, and 
might easily be beaten to less than half that thickness, if 
the purposes of trade required it. Atkin. 
The following remarks of the Bishop of Landaff, on 
Tin, on the alloys of Tin, and on the 
vessels, are very instructive. 
“ Tin ore, though it is sometimes unmixed, is often 
otherwise ; it frequently contains both tin, and iron, and 
copper. The fire with which tin ore is smelted, is suffi- 
ciently strong to smelt the ores or the other metals which 
tinning of copper 
. 
