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Hydraulic Pits at Gold Run and 

 Dutch Flat 



Approaching Gold Run a north-south belt of slate of Car- 

 boniferous age (Calaveras formation) , cut by dikes of dark 

 igneous rock, is crossed. Patches of Tertiary lavas, remnants 

 of the lava-flow which covered the plateau in Tertiary time, 

 cap the highest hills along the summit of the ridge in this 

 region. Nearing Dutch Flat Tertiary gold-bearing gravels are 

 crossed. The gravels that rest under the railroad tracks, if they 

 could be "washed" for gold, it is said would be worth $8.00 per 

 cubic yard, while gravels elsewhere that yield $1.00 to $2.00 

 per yard are worked profitably. The town of Dutch Flat is 

 almost surrounded by great pits made by hydraulic washing for 

 gold. Here is a region that was prominent in the early mining 

 days of California for its yield of placer gold. The gold came 

 chiefly from the high bench gravels which were deposited in 

 Tertiary time, and now high above the present streams. The 

 gravels were formerly washed by jets of water driven under 

 great pressure, but this method is now forbidden by law because 

 of the damage to agricultural lands below from the silt and 

 sand washed down the streams. 



In passing it is interesting to note that from a side-track on 

 the railroad near Alta round white quartz boulders, obtained 

 from the old gold washings, are shipped to Sacramento for use 

 in the furnaces of the railroad shops. The pure white cobbles 

 are left behind as the finer materials are washed away, and sur- 

 prisingly there are none of the common red granite boulders. 



Deep Gorge of American River 

 near Midas 



A little south of Midas appears a nearly sheer drop of 2,000 

 feet into the gorge of the North Fork of American River. Near 

 Gorge station on the railroad is Giant Gap or Lover's Leap. 

 This is a narrowing of the canyon caused by the fact of the 

 river here crossing a belt of igneous rock that is harder than 



