

462 



SUPPLEMENTARY INVESTIGATIONS IN THE GRAVEL REGION, 



sixty and seventy degrees. There are some deep pot-holes in the bed-rock. The bank shows next 

 the bed-rock a stratum of twenty or twenty-five feet of blue gravel, which is so compact that it has 

 to be loosened by the aid of powder drifts. Above this there are about seventy-five feet of fine 

 quartz gravel of a reddish or whitish color. The quartz pebbles, taken by themselves, are usually 

 either blue or white. There is but little pipe-clay and no volcanic cement within the present 

 limits of the mine. A quarter of a mile to the west the volcanic capping is nearly one hundred 

 feet thick. Granitic and metamorphic boulders, like those seen at Scales's Diggings and Council 

 Hill, though generally smaller in size and not requiring much blasting, are very common. There 

 seems to be no doubt that the old channel crossed from Council Hill to "Windyville, and thence 

 by way of Brandy City to Depot Hill, Camptonville, and San Juan. The precise position of the 

 deep channel at Windyville is not so clear. Mr. Arnott's view, in which I am inclined to coincide, 

 is that the connection between Windyville and Brandy City was by way of Little Cherokee ravine. 

 This would make the channel rather crooked, though scarcely more so than it is known to be in 

 other places. The width of the channel from rim to rim at W r indyville is from six to seven hun- 

 dred feet. Impressions of leaves are occasionally seen, but no evidences of animal remains have 

 been brought to light. 



Another instance of a fault formed after or during the deposition of the gravel is to be seen at 

 Arnott's mine. The diagram (Plate V, Eig. 1), is from a sketch taken on the spot. The fault crosses 

 the mine in a northwesterly direction, nearly, though not quite, coinciding with the strike of the 

 slates. To the northwest of the blacksmith-shop the hanging wall of the fault is a black slate, 

 while the foot-wall is a sandy, schistose rock, light in color. The sketch shows a section at this 

 point. To the southeast of the shop there is a different variety of rock upon the hanging wall. 

 A little easterly from the fault the bed-rock is light-colored, crystalline, and granular, resembling 

 some varieties of granite or diorite. The amount of the fault is about twelve feet, and the dip is 

 such that the gravel is found underlying the overhanging rock for eight or ten feet. The stratum 

 containing the heavier boulders on the upper side of the fault was not continuous at the same level 

 on the lower side. In connection with these obvious movements of the bed-rock, Mr. Arnott 

 pointed out to me in the gravel of the northwestern bank a peculiar soft, clayey seam, which, 

 where I saw it, was not more than two inches in width, and was not very distinct. The clay-like 

 filling of the seam showed smoothed surfaces, such as would be expected if there had been a slid- 

 ing of one part upon another. There wer<«, no marked differences in the character of the gravel on 

 opposite sides of the seam. Farther to the southeast, where the gravel has been washed away, 

 tins seam, as Mr. Arnott says, was more nearly vertical than it is at the spot where I saw it, and 

 as I have represented it in the diagram. It followed more nearly the general dip of the rocks and 

 of the fault, and was eighteen inches in width. One peculiar feature of this seam, which has long 

 attracted the attention of the miners employed at the mine, is that it has never been traced into 

 any of the overlying, horizontally stratified beds of pipe-clay. If all these different phenomena 

 are related, the fault must have been formed at some time during the deposition of the gravel. 



I could not learn anything of much value in regard to the yield of the mines in this vicinity. 

 The water used is brought in a ditch which follows the line of Canon Creek, and has a carrying 

 capacity of twelve hundred miner's inches. The washing season usually lasts about live months. 

 If rains come before snow in the fall of the year, some mining can be done in the month of 

 November ; otherwise, the ditch cannot be used until the melting of the snow in the spring. The 

 fineness of the Brandy City gold was given me as .940 for the bottom gravel and .950 for the top, 

 or, in value, from $ 18.60 to $ 19.00 per ounce. The gold at Arnott's is fine and scaly, with the 

 exception of an occasional coarse nugget. By Mr. Arnott's kindness I was allowed to take with 

 me the gold and sands from a pan of the blue gravel, which he washed in my presence The 

 mixture has been examined microscopically by Mr. Wadsworth, who says that it is made up of 

 "a few flattened and worn scales of gold associated with fragments and some crystals of zircon, 

 quartz, feldspar, augite (I), magnetite, pyrite, gray grains (platinum ?), etc. The forms are such 

 that in a majority of cases it is difficult to ascertain their true nature." 



