METALLURGICAL PRACTICE. 



to prevent amalgam-thefts (see fig. 7). The plates are in two 

 tiers, each 5 feet square, the lower one tapering to 3 feet. 



The tailings from the 

 mills run into settling pits 

 whence the sands are dis- 

 charged by hand-labour, 

 and stacked for exposure 

 to the atmosphere before 

 being submitted to the 

 cyanide treatment. Priest 1 - 

 man dregers were tried, but 

 on account of the waste of 

 water, which is not too 

 abundant on the field, their 

 use had to be abandoned. 

 With hand-labour tha 

 sands pack better and the 

 waste of water is obviated. 

 The cost of emptying the 

 settling pits is charged to 

 milling. 



The practice of grinding 

 mill-tailings with mercury 

 in Wheeler pans, which till 

 recently was in favour at 

 Kolar, has been practically 

 abandoned since the intro- 

 duction of the cyanide 

 treatment on a large scale; although it still lingers to some extent at 

 the Ooregum Mine. 



According to the returns published by the Mysore company 

 9 2 )343 tc, ns of ore were milled during the year 1899, producing 

 156,128 ounces of standard gold, having a value of £606,947. 

 This is equivalent to a yield from all sources of 31 dwts. of fine gold 

 to the ton of ore. According to the Superintendent's report the 



Fig. 7.— Mortar-box, Champion Reef 



New mill (1,2501b. stamps). 



Scale ii''= 2 ft. 



