The California Stamp Mill California Digital Library
The interior of a quartz mill at Grass Valley, Nevada County, the leading center of hardrock mining, as illustrated in the October 1857 issue Hutchings'' California Magazine.. To the rear stand two fourstamp batteries, or mills. The castiron quot;stampers,quot; or pestles, weighing from six hundred to a thousand pounds, were raised by the revolving horizontal driveshaft and then fell with tremendous