In the early days the building of quartz-mills kept pace with the building up of the towns. As early as October, 1859, Logan & Holmes had a four-stamp horse-power mill in operation at Dayton, and Hastings & Woodworth had two water-power arastras at work, which reduced six tons of ore a day. This ore was not worked as silver ore. It was from the surface of the Comstock Lode, at Gold Hill, and was worked for gold only. In the spring of 1860 many mills for working silver ore began to be erected.
The First Silver Mill.
The first silver-mill that went into operation was the “Pioneer,” erected by Almarin B. Paul, on Gold Canyon, at the north end of Silver City, just below the Devil’s Gate. It was a steam mill and contained twenty-four Howland rotary stamps and twenty-four amalgamating pans. The work of erecting the mill was commenced May 24, 1860, and it began work August 13, the same year. Some others have claimed the honor of starting the first quartz-mill in Nevada, but this was undoubtedly the first silver-mill. In it were operated the first silver amalgamating pans ever seen anywhere. The iron amalgamating pans were the result of experiments made by Almarin B. Paul before he began the erection of his mill. He thought the German barrel process and Mexican patio too slow, and began to make experiments with some small iron pans that had been in use at some of the quartz-mills in California for grinding and working the sulphurets saved by concentrating machines in working the quartz of the gold mines. The best of these was found to be the “Knox Improved Pan,” in which was a false bottom that formed beneath the pan a steam-tight heating chamber. By the use of this kind of pan, and by treating the heated pulp with certain quantities of salt, sulphate of copper, and some other chemicals, before adding quicksilver, it was found that a charge (whatever amount of crushed silver ore the pan would hold) could be amalgamated in about three hours. The results obtained with Knox’s Improved Pan were so satisfactory that Mr. Paul placed pans of that pattern in his new mill. Soon after a score of pans of different styles were invented, and to this day pans of new patterns are still being invented and patented.
The Coover & Harris Mill, Gold Hill, was the first mill in the country to start up with steam. It blew its steam whistle a day before that of Paul’s “Pioneer” was heard, but it could not then be called a silver-mill as it was working gold quartz, the same as was worked, in October the year before, at Dayton, by Logan & Holmes and Hastings & Woodworth. The mill had a fifteen horse-power engine that drove an eight-stamp Howland rotary battery and crushed six tons of ore a day. At first it was a dry crusher, but soon Paul’s Concentrators and Knox’ pans were used. The Harris of the firm was Dr. E. B. Harris, now a resident of Virginia City.
The Many Mills of the Early Days.
Very soon after these first mills went into operation several others started up. By the spring of 1862 no fewer than eighty-one quartz-mills were at work, the majority of them on ore from mines situated on the Comstock Lode. These mills were located in Virginia City, on Six and Seven-mile Canyons, at Gold Hill, Silver City, Dayton, at Empire City, and all along the Carson River below that town; two or three near Carson City (on Clear Creek and Mill Creek), and a dozen or more about Washoe Valley and down toward Steamboat Valley. Many of these mills were of small capacity, having only from two to ten stamps, but there were already a few first-class reduction works, as regards capacity, though their methods and processes were defective. The reduction works of the Ophir Company, in Washoe Valley, cost $500,000, contained thirty-six stamps, were driven by an engine of 100 horse-power, and was capable of working 100 tons of ore a day. The Gould & Curry Mill then building on Six-mile Canyon was of still greater capacity, and the Land, Bassett, Winfield, Empire State, Central, Marysville, Trench, Swansea, Phœnix, Succor, Rock Point, Merrimac, Vivian, and several other mills, contained from fifteen to twenty-five stamps each. After the completion of the Virginia and Truckee Railroad the majority of the outside mills (mills to which it was necessary to transport ore, wood, and other supplies by wagon) were pulled down and removed to new mining camps in various parts of the State. The greater part of the ores of the Comstock were then reduced in steam mills near the mines or in water mills on the Carson River on the line of the railroad; and this is still the case.
We now have fewer mills than in the early days, but they are of greater average capacity, and are in every respect more effective than were those first erected. More ore is crushed to the stamp, and the time required for the amalgamation of the pulp has been very materially reduced. All the present mills are so constructed that there is very little handling of the ores operated upon, and labor-saving apparatus has been introduced into nearly every department. Even the old oil lamps are being thrown out of the mills and the electric light introduced.
REDUCTION WORKS OF THE PRESENT DAY.
Description of the Process of Working Comstock Silver Ore.
In speaking of the works at present in use for the reduction of silver ore, it will only be necessary to describe the process in use in one mill, as all work after the same system. Being the most recently erected, and quite perfect in all its arrangements, the new mill of the Nevada Mill and Mining Company, commonly called the Chollar Mill (as it stands near the Chollar old shaft), shall furnish the illustration necessary to an understanding of the method of working Comstock ores now generally in use. The mill covers nearly an acre of ground, and the machinery is at present (March, 1889) driven in part by a Pelton water wheel 11 feet in diameter, and in part by power electrically transmitted from the Sutro Tunnel level. The mill building stands in a depression near the head of a small ravine. Such a site was selected in order that from the time the ore enters the mill its course at each stage necessary to its complete reduction, shall be downward—that there shall be no lifting or hoisting of ore or pulp.