MURPHREE'S VALLEY; MANGANESE ORES. 113 



bottom of the deposit, the ore chunks are more numerous, 

 and seams of the pulverulent black oxide penetrate into the 

 underlying clay. On the east side of the gorge this deposit 

 is not seen. If it exists there, it is wholly covered over by 

 earth and soil. But where it is seen on the west side, it is 

 wholly on the surface, no rock, or soil covers it. No rock, 

 except occasional pieces of soft chert, exists in it. The 

 question naturally arises, how could such a formation have 

 been produced ? If resulting from decomposition like wad, 

 it would have been more mixed with impurities. Its pres- 

 ent position gives no indication of a basin. From whatever 

 source it came, and however formed, it was certainly once 

 roofed in with rock and solid earthy strata. These have 

 been removed by erosion, and probably much of the man- 

 ganese also. It is scattered for several hundred yards down 

 the slope, north, and east of the deposit. Another similar 

 deposit, but much smaller, was once on the surface about 

 300 yards to the south, and 80 feet higher. This was about 

 two feet thick, and 20 to 30 feet in diameter. A deep test 

 shaft was sunk here to see what lay beneath. Nothing was 

 found, except small pieces, and seams, and dendritic in- 

 crustations of manganiferous matter o,n the rocks. These 

 were very marked, until the shaft had penetrated strata, 

 which owing to the dip, Jay beyond the deposit. This shaft 

 was sunk nearly 100 feet, but it did not reach the supposed 

 underlying manganiferous chert. A marked feature in it 

 was, the loose, seamy and partly decomposed rock^ encoun- 

 tered in all the strata lying leneath the manganese deposit. 



Owing to long exposure much of this surface deposit is 

 decomposed, and without washing, would not give a high 

 enough per centage. of dioxide of manganese to be market- 

 able. The amount of salable ore that exists here cannot 

 therefore be estimated, but it probably exceeds the annual 

 product of all the mines in the United States. (1882.) 



South-west from this large surface deposit about quarter of a 

 mile, surface out crops of pyrolusite ore were plainly seen, 

 and at nearly the same geologic level. Th^se indicated a 

 regular stratum of ore. It had been dug into in several 



