414 BOOK IX. 



sized tin-stone which melts quickly, but less of the large ones which melt 

 slowly, and a moderate quantity of the medium-sized which holds the middle 

 course. Those who do not smelt the tin-stone in furnaces made sometimes 

 wide, sometimes medium, or sometimes narrow, in order that great loss 

 should not be occasioned, throw in first the smallest size, then the medium, 

 then the large size, and finally those which are not quite pure ; and the blast 

 of the bellows is altered as required. In order that the tin-stone thrown 

 into the furnace should not roll off from the large charcoal into the forehearth 

 before the tin is melted out of it, the smelter uses small charcoal ; first some 

 of this moistened with water is placed in the furnace, and then he frequently 

 repeats this succession of charcoal and tin-stone. 



The tin-stone, collected from material which during the summer was 

 washed in a ditch through which a stream was diverted, and during the winter 

 was screened on a perforated iron plate, is smelted in a furnace a palm wider 

 than that in which the fine tin-stone dug out of the earth is smelted. For 

 the smelting of these, a more vigorous blast of the bellows and a fiercer fire 

 is needed than for the smelting of the large tin-stone. Whichever kind of 

 tin-stone is being smelted, if the tin first flows from the furnace, much of it is 

 made, and if slags first flow from the furnace, then only a httle. It happens 

 that the tin-stone is mixed with the slags when it is either less pure or 

 ferruginous — that is, not enough roasted — and is imperfect when put into 

 the furnace, or when it has been put in in a larger quantity than was neces- 

 sary ; then, although it may be pure and melt easily, the ore either runs 

 out of the furnace at the same time, mixed with the slags, or else it settles 

 so firmly at the bottom of the furnace that the operation of smelting being 

 necessarily interrupted, the furnace freezes up. 



The tap-hole of the forehearth is opened and the tin is diverted into the 

 dipping-pot, and as often as the slags flow down the sloping floor of the build- 

 ing they are skimmed off with a rabble ; as soon as the tin has run out of 

 the forehearth, the tap-hole is again closed up with lute mixed with powdered 

 charcoal. Glowing coals are put in the dipping-pot so that the tin, after it 

 has run out, should not get chilled. If the metal is so impure that nothing 

 can be made from it, the material which has run out is made into cakes to be 

 re-smelted in the hearth, of which I shall have something to say later ; if the 

 metal is pure, it is poured immediately upon thick copper plates, at first in 

 straight lines and then transversely over these to make a lattice. Each of 

 these lattice bars is impressed with an iron die ; if the tin was melted out 

 of ore excavated from mines, then one stamp only, namely, that of the 

 Magistrate, is usually imprinted, but if it is made from tin-stone collected on 

 the ground after washing, then it is impressed with two seals, one the 

 Magistrate's and the other a fork which the washers use. Generally, three 

 of this kind of lattice bars are beaten and amalgamated into one mass with a 

 wooden mallet. 



The slags that are skimmed off are afterward thrown with an iron shovel 

 into a small trough hoUowed from a tree, and are cleansed from charcoal 



