296 EESOUllCES OF CALIFORNIA. 



Kcrtli Fork of the American River runs through the middle of 

 the comity, and the Middle Fork forms its southern boundary. 

 The principal mining towns are Auburn, Yankee Jim's, Gold 

 Hill, Dutch Flat, Todd's valley, Michigan City, Iowa Hill, 

 Bath and Wisconsin Hill. Two-thirds of the present gold yield 

 of the county is derived from hydraulic claims. 



Some of the placer diggings near Bath are found in a peculiar 

 formation. The principal deposit is in a deep hill, at the bot- 

 tom of which is a stratum of pay-dirt, consisting of a fine sandy 

 sediment, with pebbles and pieces of quartz. The gold is 

 round and coarse. Above that is a stratum of blue gravel, 

 which varies from twenty to one hundred and fifty feet in 

 thickness. This blue gravel is " spoted ;" that is, in places it 

 pays well ; in other places it does not pay at all. Above this 

 stratum is another layer of pay-dirt composed of a reddish 

 gravel, which is about three feet thick on an average, and con- 

 tains little scales of gold. The top of the ridge is composed 

 of a whitish cement or tough clay, which, where exposed to 

 the air, is reddish in color, and resembles the red gravelly clay 

 found in most of the hills in the rich mining districts. 



§ 223. El Dorado and Amador. — El Dorado county ad- 

 joins Placer on the south, and is drained by the South Fork 

 of the American River, which runs through its centre, the 

 Middle Fork, which is its northern boundary, and the Cosum- 

 nes its southern boundary. It is the oldest placer-mining 

 county of the Sacramento basin, Marshall having made his 

 discovery within its limits ; and ten years ago it was called 

 the " Empire County," because it cast the largest vote in the 

 state, but it has now lost much of its population and fallen be- 

 hind several others. The principal mining towns are Flacer- 

 ville, Coloma, Georgetown, Diamond Springs, El Dorado, 

 Spanish Bar, and Indian Diggings. In 1859 there were forty 

 quartz-mills in the county, of which six are at El Dorado, 

 three at Steeley's Fork, at Placerville, Nashville, Grizzly 

 Flat, Loafer Hollow, and Logtown two each, and the others 

 are scattered about. The county has fifty-one ditches, twelve 



