

464 



SUPPLEMENTARY INVESTIGATIONS IN THE GRAVEL REGION. 





feet above the tunnel. The bed-rock brought out from the tunnel was very soft and of a green 

 color, resembling a chloritic or talcose schist. 



The portion of the ridge lying to the northeast of Eureka I made no attempt to examine. 





E. Monte Cristo and Craycroft's. 



These two places can be easily reached by good trails from Downieville. The former is upon the 

 ridge between Goodyear Creek and the North Fork of the North Yuba River, and the latter upon 

 the spur between the middle and west branches of the North Fork of the North Yuba. The position 

 of Monte Cristo is shown upon the map (Plate B), though perhaps not with accuracy. Cray croft's 

 would also fall within the limits of that map, but I have no good data for fixing its position. On 

 my trip to Monte Cristo I followed first the western trail from Downieville, then crossed the ridge 

 to Excelsior, and returned by the Excelsior trail. A subsequent day was taken for the visit to 



* 



Craycroft's. 



The country rock near Downieville is an easily cleavable slate. It shows frequent alternations 

 of color, and the fresh surfaces of cleavage are often fantastically variegated. Across the slate there 

 is a belt of serpentine, which strikes a little to the west of north. It is probably a part of the 

 belt which is seen at Deadwood and at Whiskey Diggings. The eastern border of the serpentine 

 can be seen at several points on the Excelsior trail ; its western border crosses the mines at Monte 

 Cristo. At the Empire tunnel the rock at the mouth is slate ; the serpentine appears about 400 

 feet from the mouth. At Excelsior the bed-rock is slate. 



Twenty years ago Monte Cristo was a flourishing mining camp. At an election in 1859 nearly 

 a thousand votes were cast : now the total population does not exceed thirty persons. The most 

 of the gold obtained came from drift mines ; hydraulic mining has amounted to but little. The 

 claims used to be laid out parallel to each other, in a direction N. 20° K, fronting on the canon of 

 Goodyear Creek, and extending back to the middle of the ridge. Within a distance of a third of 



a mile there were a half-dozen or more long tunnels. 



The lengths of some of these were given me 



The gravel that I saw was 



by Mr. Thatcher. Beginning at the southeast, they are as follows : Empire, 1,400 feet ; Swallow, 900 ; 

 Poodle, 700 ; Exchange, 1,300 ; Cold Spring and Bigelow, 700. Many of these tunnels have been 

 allowed to cave in and are no longer accessible. The only one that I entered was the Empire. I 

 determined the altitude of the mouth of this tunnel to be 5,010 feet, 

 a clean white quartz. It was from this mine that the "petrified knot-hole," specimen 122, came. I 

 had the specimen taken from the charred trunk of a large tree, which was lying in a horizontal 

 position in the gravel and could be traced for at least thirty feet. The old Empire incline is 

 said to have passed through one hundred feet of line quartz gravel, forty feet of pipe clay, then 

 a little more gravel, and finally the volcanic cement to the surface, the total distance being 500 



feet. 



My determinations of altitude at Monte Cristo I regard as more trustworthy than those made at 



Eureka and Mugginsville. The observations with the hand-level at Monte Cristo agree with those 

 made at Chaparral Hill so far as to place beyond doubt the fact that the Monte Cristo bed-rock is 



— than that at Hardee's tunnel or Mugginsville. 

 The altitude of Mr. Thatcher's house at Monte Cristo I made to be 5,056 feet. The southwestern 

 rim of the channel is at a little lower altitude than this. Its course is about S. 62° E. (magnetic) 

 along the front of the mines ; it then turns to the east and crosses under the volcanic cement to 

 Excelsior, which is on the opposite side of the ridge and nearly due east from Monte Cristo. That 

 the gravel extends through the ridge, has been proved by at least one underground connection. The 

 pay channel, between the rising rims on the north and south, is about 700 feet in width ; beyond 

 that limit the gravel was not rich enough to pay more than three or four dollars a day to the man. 

 In regard to the direction of the flow of the old stream between Monte Cristo and Excelsior, the 

 evidence is conflicting. Some persons told me that the fall of the bed-rock is from east to west ; 

 others that it is in just the opposite direction. My determination of the altitude of the mouth 

 of one of the tunnels at Excelsior, 5,020 feet, is not sufficient to settle this question. 



higher — probably more than a hundred feet higher 













X 



