



BETWEEN INDIANA HILL AND QUAKER HILL. 



421 





to attempt to collect detailed information upon this point, and I cannot give any list of incor- 

 porated companies or other mining organizations. The tendency is towards the consolidation of 

 individual claims in the hands of large companies, with sufficient capital to control both the 

 gravel and the water supply. 



The published portion of my former report contains but little in regard to the lithological char- 

 acter and the stratigraphical features of the gravel of this region and its included boulders. The 

 removal of the gravel to bed-rock at so many new places enables me now to present additional 

 information upon these points, and, incidentally, upon the results of some of the more recent 

 mining work. 



The deep gravel at Indiana Hill, which is a part of the property belonging to the Gold Run 

 Ditch and Mining Company, has been worked through a deep bed-rock tunnel from Canon Creek. 

 The main tunnel was driven 050 feet in the direction of the old 1849-54 shaft in Potato Ravine, 

 which it will take, 1,600 feet more to reach ; and then a branch tunnel, 1,600 feet in length, was 

 driven to Indiana Hill, which at its extremity was ninety feet below the deep bed-rock. A section 

 of bed-rock, about 100 by 150 feet in dimensions, has been exposed and roughly cleaned up; and 

 the gravel has been removed nearly to bed-rock over an area of about 500 feet square, or nearly 

 six acres. For from four to six feet above bed-rock the gravel is a very hard blue cement, so hard 

 that it does not get broken up by the water in the sluices, and consequently carries gold away to 

 the canon. On exposure to the weather, however, it gradually disintegrates and can be more 

 easily moved. This cement Mr. Gould, the superintendent, proposes to treat in special mills to be 

 built in the mine and be run with hurdy-gurdy wheels. Above this hard cement come from forty 

 to sixty feet of a cement which can be easily worked with the aid of powder. Including these two 

 strata, the blue gravel is about 200 feet in thickness. Like the other blue gravel of the district, 



this becomes rapidly red in color when exposed to the air. In this gravel there is an exception- 

 ally small number of large boulders. Those which are met with represent several varieties of 

 metamorphic rock, and the spaces between them contain a considerable quantity of quartz pebbles. 

 Above the blue gravel comes the white or red variety, extending either to the original surface, 

 or to the bottoms of the old workings, where the upper bench has been already removed. The 

 top of the present highest bank is fully 400 feet above the deep bed-rock. The width of the 

 channel a short distance from this point was estimated at 1,200 feet. The gravel of Indiana Hill 

 is also remarkably free from strata, or even streaks, of clay. Here and there are local spots of 



a bluish sand, from a few incli.es to three feet in thickness, but not traceable in a continuous 

 layer. Taken all in all, the Indiana, Hill bank must be selected as the best specimen of a clean, 

 uniform gravel deposit that I saw anywhere in the State. 



At the Cedar claim an area of bed-rock of about 150 by 200 feet has been uncovered, which 

 shows a decided pitch towards Indiana Hill. The gravel is similar to that at Indiana Hill, though 

 there are more large boulders, particularly Oil the western rim. 



'idie two claims on Dutch Flat Hill in which bed-rock has been reached — the Southern Cross 

 and the Polar Star — have been opened by deep tunnels from Bear River, and at both places 

 there are now deep, funnel-shaped excavations, in which can be seen about 150 feet in thick- 

 ness of blue gravel at the bottom, and fifty feet or more of white quartz gravel above, reaching 

 to the present surface of the ground. The original top gravel was washed away many years 

 ago. At the Polar Star mine I saw several patches of red gravel, within the limits of the blue 

 stratum, which had very peculiar shapes. They were not simply filling old depressions in the 

 blue gravel, but were entirely surrounded by the blue, which by itself would not stand in place 

 "without supports if the red portions were removed. The blue gravel turns red very rapidly when 

 water runs over it, as, for instance, where the waste water from the surface is allowed to run down 

 the bank. The boulders in the blue gravel, like those at Indiana Hill, are almost exclusively of 

 metamorphic rock ; a piece of quartz as large as one's head is rarely seen. The interstices between 

 the boulders, however, are almost always filled with white quartz. These blue boulders are large 

 in size, up to ten or twelve feet in diameter, and pervade the whole of the blue gravel. They show 





