Alt. X.] Watson, Yellow OcJier- Deposits of Gioi-gia. 219 



With one exception, the form of washer in use at the 

 different plants in the district is of the kind used in washing the 

 manganese and brown iron-ores, known as the log-washer, and 

 has been described by me in a former paper, ' entitled "The 

 Geologic Relations of the Manganese Ore-Deposits of Georgia. "■ 



The form of washer in use at the Blue Ridge Ocher Com- 

 pany's plant was planned for the purpose of diminishing the 

 grinding and rubbing action of the log-washer, and thereby de- 

 crease proportionately the resulting percentage of finely divided 

 impurities, principally sand and manganese dioxide, which 

 would be floated with the ocher. The washer consists of a 

 V-shaped box about 7 ft. in length, 5 ft. high, and 3 ft. wide at 

 the top. In the bottom of the box is fastened a 3-in. pipe with 

 i/^-in. perforations along the top at intervals of about 1.25 in. 

 The water is introduced into this pipe, and passes into the box 

 through the perforations in the pipe. Over this pipe revolves a 

 shaft set with i-in. pins so arranged that those of one row fall 

 just halfway between those of the next, giving a spacing of 2- 

 in. between pins, if they were aligned in the same row. 



By this arrangement the ocher is sufficiently disintegrated 

 without being subjected to the grinding and rubbing action of 

 the ordinary log-washer. The water containing the suspended 

 particles of ocher overflows at the top of the washer-box into a 

 line of troughs, through which it passes into the settling-vats. 

 The ocher is further purified by the settling of a portion of the 

 impurities along the bottom of the troughs in transit to the vats. 

 After the overflow becomes thin, showing that the ocher in the 

 charge is about exhausted, a long narrow door at the bottom 

 of the washer is raised and the sand, clay, etc., mixed with 

 some ocher, are washed through and carried off in a trough as 

 waste. 



I am reliably informed by the manager of this plant that 

 the washer of the size above stated easily handles from 25 to 30 

 tons of ocher per day of ten hours, and that all the necessary 



* Trans. ^ xxxiv., p. 207. 



- Reprint, BtdUtin Scientific I.a/'oratorics of Dc'ni^on University, 1904, N'ol. 

 XII, Art. X, pp. 146-198. 



