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 taleose schist. 
The portion of the ridge lying to the northeast of Eureka I made no attempt to examine. 
E. Monte Cristo aNnD 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 R), though perhaps not with accuracy. Craycroft’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° E., fronting on the caiion 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 
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 1 entered was the Empire. I 
determined the altitude of the mouth of this tunnel to be 5,010 feet. The gravel that I saw was 
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 fine quartz gravel, forty feet of pipe clay, then 
a little more gravel, and finally the voleanic 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 
higher — probably more than a hundred feet higher—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. 
