68 



best artificial brass, and is called Laxa copper, from 

 the river of that name in the vicinity of the mine. 



The method of melting the ore is very simple : 

 After separating it from the earth and superfluous 

 matrix, it is broken into small pieces with wooden 

 pestles. These pieces are placed between layers of 

 wood, which are set on fire, and the heat kept up 

 with a large bellows moved by water. The furnace 

 is constructed of an adhesive clay ; but the bot- 

 tom, which is slightly inclined towards the centre, 

 is formed of a cement of plaister and calcined 

 bones. The vault contains a sufficient number of 

 outlets for the smoke, and at the top is an aperture 

 that may be closed or opened at pleasure, which 

 serves for the introduction of ore and fuel. 



At the bottom of the furnace is a hole for the 

 passage of the liquefied metal, which is conveyed 

 into a receptacle, and from thence taken and refined 

 in the European manner. 



I do not know what quantity of copper is annu- 

 ally obtained from the mines, but from the expor- 

 tation it must be very considerable. Five or six 

 ships sail every year for Spain, each of which usually 

 carries twenty thousand quintals or upwards. Much 

 is also sent to Buenos- Ayres by land ; and the Pe- 

 ruvians, who have an extensive commerce with the 

 coast, export at least thirty thousand quintals yearly, 

 which is principally employed in their sugar works. 

 Besides which the quantity made use of in the can- 

 non foundries, and for domestic purposes, is by no 

 means inconsiderable. 



