GEOLOGY AND MINEKAL EKSOURCES OF SIKHIM. 65 



upper end, the surplus water flowing' off in a parallel channel. In tha 

 case of very dirty " dhan" the powdered ore is put through a wooden 

 sieve, the refuse called " maddam " being thrown away, while the 

 other portion, chan chamru, is again ground in the "jhatoo" and 

 afterwards washed. 



The powdered ore is now washed in these troughs, and continu- 

 ally agitated by the hand : in this way the dust and lighter particles 

 containing but little ore get washed down the troughs by the flowing 

 stream, leaving only the heavier particles containing copper ore. 



These copper particles are taken to the blacksmith's house, where 

 the smelting operations ai'e carried out. These blacksmiths belong to 

 the " Muhur" branch of the " Kamis." 



The ore, whether in pure lumps or in powder as above mentioned, 

 is taken to the smelting house (afur), in which there is a furnace 

 ("tora") built down into the floor and lined with some neatness with 

 refractory clay, about 18 inches deep, a foot square at the top, and 

 tapering a good deal towards the bottom. Small charcoal is first filled 

 in to a depth of about a foot and beaten down by a wooden rammer 

 till a saucer-shaped floor of coarsely powdered charcoal is formed, 

 sufficiently compact to prevent the products of the smeltings sinking 

 into it. These protect it from the blast, and it is besides too compact 

 to burn easily. There is no orifice in this part of the furnace. Two 

 clay tuyeres dip nearly vertically about three inches into it from 

 the top, and are respectively connected with skin bellows by horizontal 

 tubes about a yard long. The tubes are formed of clay mixed with 

 chopped straw, and are moulded on a straight stick, which is subse- 

 quently withdrawn. 



The furnace thus prepared is lighted up with charcoal, and the 

 bellows at each side worked alternately. When at its full heat the 

 powdered ore is sprinkled in at short intervals, until a sutficient 

 amount of regulus or chakhoo, as it is called by the smelters, has col- 

 lected at the bottom of the furnace, covered by the lighter slag. The 

 charcoal is then raked away and the surface of the slag(" keet") cooled 

 • with a whisp of wet straw tied to a stick. The solidified cake is 

 removed and the fresh surface cooled : in this way the slag is taken off 

 in two or three successive cakes, leaving the heavier and more per- 

 fectly fluid regulus behind, which is afterwards cooled and extracted. 



The regulus is then pounded and ground in the jhatoo, mixed 

 with an equal amount of cowdung, and made into balls about the 

 size of oranges, often called " paira." After drying, a quantity of 

 these are spread on a layer of charcoal in a place surrounded by stones 

 and covered with charcoal, then a second layer of balls, and tlien 

 more charcoal. The whole is then ignited, and the regulus thus roasted 

 with free access of air; this roasting lasts nearly twenty-four hours. 



