THE WASHINGTON RIDGE. 411 
average height of bank at the time those “claims” were worked, the yield per cubic yard was 
about 13} cents. 
There being some uncertainty about the area covered by the gravel between Omega and Diamond 
Creek, I thought it necessary to extend my examination in that direction. In so doing I followed 
first the line of the Omega ditch to a point opposite the Diamond Creek diggings, and subsequently, 
for a part of the way, the Blue Tent ditch, which runs nearly parallel to the other but at a higher 
altitude. The difference of altitude between the two ditches at a point near Omega I made to be 
170 feet. On the Omega ditch I first saw bed-rock near the head of Iowa Ravine. Its altitude 
was about forty feet higher than the highest surface of the gravel at Omega. For the rest of the 
distance as far as Diamond Creek I saw in the ditch nothing but slate, or some other variety of 
schistose bed-rock. Upon the top of the ridge between Iowa Ravine and Missouri Caiion, 
near where the ditch is carried through a short tunnel, there was a small deposit of rolled gravel 
which very likely was once connected with the high bench at Gold Flat. There had been an 
opening made of perhaps 300 feet in diameter and fifteen in depth. The Blue Tent ditch was in 
lava until after the crossing of the spur between Iowa Ravine and Missouri Cajion, and from that 
point on in slate as far as the second or third branch of Diamond Creek, which was the limit of 
my walk in that direction. I went far enough to satisfy myself that the quartz gravel, said to be 
seen in the Blue Tent ditch above Missouri Cafion, had no obvious connection with the deposit at | 
Omega. 
The gravel at Diamond Creek extends for half a mile or more, principally upon the right or 
eastern bank of the creek, and about one hundred and fifty feet above its present bed. I took one 
observation for altitude upon the bed-rock near the old blacksmith-shop, just above the mouth of a 
tunnel. I made the altitude at this point to be 4,206 feet. I saw no one at work. The bed-rock 
has a steep pitch down the creek, and also a more gradual inclination under the bank of gravel 
lying to the east. At one of the lower banks, farther down the stream, the top of the gravel was 
on a level with my point of observation. Back of the gravel, bed-rock hills rise rapidly to a con- 
siderable height. The gravel differs very much in appearance from that at Omega. It looks more 
like an irregularly stratified drift, with small boulders distributed from top to bottom through a 
reddish sandy gravel. Many of the boulders were evidently of volcanic origin, though not all. At 
one of the lower banks, as seen from across the creek, the gravel appeared to be finer and lighter- 
colored. 
Taking all these facts into consideration, I was led to the conclusion that the gravel at this 
point represents some former channel of Diamond Creek alone, and that there never was any 
direct connection with the Omega deposit. 
From Omega I went by stage to a point about a mile below the Central House, and thence 
on foot to Blue Tent and Sailor Fiat; but before reporting upon this portion of the ridge I will 
add a few words about a small deposit of low gravel, which probably owes its origin to the 
washing away of the old channel between Alpha and Omega. 
The Hathaway claim, on the south bank of the South Yuba, at the mouth of Scotchman’s 
Creek, about a mile above Washington, presents one or two features of interest. There is no 
precisely similar deposit that I have heard of along the river, either above or below. The gravel 
is reputed to extend back from the river for at least a quarter of a mile. Near the Yubsa it 
has a thickness of twenty-five feet, the lower half being blue in color while the top is red. 
Farther from the river the thickness is considerably greater, a bank of two hundred feet being 
looked for in some parts of the claim. This deposit has been prospected by means of tunnels 
from the Yuba and from Scotchman’s Creek, each about 1,200 feet in leneth. The mouth of 
the latter tunnel is now buried seventy feet beneath tailings. It seems almost beyond ques- 
tion that this deposit came from the washing away by natural causes of a portion of the old 
channel between Alpha and Omega, and it is probable that it has been caught where it is in 
consequence of a change in the courses of the ravines, for there is some evidence that there 
was formerly a different outlet, a little lower down the Yuba, for Krumbacher Ravine, or Scotel- 
