HISTORICAL NOTES: 3IIXIXG, METALLURGICAL AXD STATISTICAL. 35
The stamp-mill, or, as it was originally called, the "pounding mill," was most probably a European innovation. As early as 1836 a 6-stamp mill, with 50-pound stamps, was in operation at the Tellurium mine in Virginia. In 1837 a Frenchman erected a mill at the Haile mine in South Carolina. These primitive mills were constructed of wood, with iron shoes and die-plates; the general type of construction was similar to that of the present California mills, with the exception that the stems were square and did not revolve, the cams working in slots or recesses cut into the stems. A few of these old-fashioned mills may still be seen in operation in Georgia in the Nacoochee valley, seemingly serving the purpose of the tributors and petty quartz miners, and it is stated that they are operated at a fair profit. They are cheaply constructed, a 10-stamp mill with water-wheel and building complete costing about $150. The amalgamation is done on a copper plate of the width of the battery and about one foot long.
The first regular California battery was erected at the Kings mounain mine, in North Carolina, just after the war; and in 1866 a similar mill was built at the Singleton mine, in Georgia, by Dr. Hamilton.
Besides mills of Western manufacture, there are two types which are common to the South. One of these is an excellent 750-pound mill built by the Mecklenburg Iron Works of Charlotte, 1ST. G, a slight variation of the Western type (described on p. 119). The other is the 450-pound Hall mill, which is peculiarly adapted to the saprolitic ores of the Dahlonega district in Georgia (described on pp. 110-113.)
Various types of rotary pulverizers and pan amalgamators have been introduced in the South from time to time, supposedly as improvements on the stamp-mill, as, for instance, the Howland mill, a flat circular disc revolving in an iron shell; and, similarly, the Crawford (with revolving iron balls) and the Huntington mills; the Parson mill, not unlike the Howland, but covered with a hood, and having the interior grinding surfaces coated with lead-amalgam; the Meech mill, in which the quicksilver was comminuted by superheated steam; the Wiswell mill, being practically an iron Chilean mill fed with corrosive sublimate in connection with an electric current; the Nobles process, in which the ore was ground to 100-mesh between buhr-stones and the. pulp run over amalgamated slabs of zinc or lead. Revolving Freiberg barrels were also used at some of the mines. The Blake system of fine crushing, combined with subsequent wet grinding,1 was introduced at the Haile mine in 1884, but was soon abandoned in favor of the present stamp-mill.
The above are simply cited as a few examples of the vast number of mechanical appliances for grinding and amalgamation with which the
! Trans. Amer. Inst. Miiihit] EvyiHt'ery, vo]. xvi. p. 755.
