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In the early 1850s, '49ers on their way to California as part of the Gold Rush discovered small placer gold deposits in the vicinity of Dayton, Nevada. These deposits were followed up Six-Mile Canyon, where veins of gold-flecked decomposed quartz underlying a heavy blue-black sand were discovered. This sand was viewed as a nuisance until an assay determined that it was, in fact, a rich silver ore far more valuable then the gold ore beneath it. The deposits of this ore came to be collectively referred to as the 'Comstock Lode' after Henry Comstock who was the most conspicuous claim holder in the area.

News of this discovery spread quickly and soon hundreds and then thousands of people flocked to the area. The ore was first extracted through surface diggings, but these were quickly exhausted and miners had to tunnel underground to reach ore bodies.

Unlike most silver ore deposits which occur in long thin veins, those of the Comstock Lode occurred in discrete masses often hundreds of feet thick. The ore was so soft it could be removed by shovel. Although this allowed the ore to be easily excavated, the weakness of the surrounding material resulted in frequent and deadly cave-ins.

The cave-in problem was solved by the method of square-set timbering invented by Philip Deidesheimer. Previously timber sets consisting of vertical members on either side of the diggings capped by a third member were used to support the excavation. However the Comstock ore bodies were too large for this method. Instead, as ore was removed it was replaced by timbers set as a cube six feet on a side. Thus the ore body would be progressively replaced with a timber lattice. Often these voids would be re-filled with waste rock from other diggings after ore removal was complete.

As the depth of the diggings increased, the hemp ropes used to haul ore to the surface became impractical, as their self-weight became a significant fraction of their breaking load. The solution to this problem came from A. S. Hallidie in 1864 when he developed a flat woven wire rope. This wire rope went on to be used in San Francisco's famous cable carCable car can mean: a light rail system using a cable in the road to pull the light rail cars along; see Cable car on rails. a cabin suspended along a cable in the sky, pulled by a cable; see Aerial lift.s.

Intrusion of scalding-hot water into the mines was a large problem, and the expense of water removal increased as depths increased. In 1871Events January January 18 The member-states of the North German Confederation unite into a single nation-state known as the German Empire. The King of Prussia is declared the first German Emperor as Wilhelm I of Germany. January 28 France surrenders to en the Sutro Tunnel was driven up from the valley near Dayton through nearly four miles of solid rock to meet the Comstock mines approximately 1,650 feet beneath the surface. The purpose of the tunnel was to provide drainage and ventilation for the mines as well as gravity-assisted ore removal. However by the time it reached the Comstock area mines, most of the ore above 1,650 feet had already been removed and the lower workings were 1,500 feet deeper still. Although virtually no ore was removed through the tunnel, and the ventilation problems were solved at about the same time by the use of pneumatic drills, the drainage it provided greatly decreased the operating costs of the mines it serviced.

Peak production from the Comstock occurred in 1877Events January 1 Queen Victoria proclaimed Empress of India by the Royal Titles Act, introduced by United Kingdom Prime Minister Benjamin Disraeli. January 8 Crazy Horse and his warriors fight their last battle with the United States Cavalry ( Montana) Ja, with the mines producing over $14,000,000 of gold and $21,000,000 of silver that year. Production decreased rapidly thereafter, and by 1880Events January 1 Construction of the Panama Canal begins February 2 The first electric streetlight is installed in Wabash, Indiana February 13 Thomas Edison becomes the second person to observe the Edison Effect. February 17 Bomb explodes in Winter Palace the Comstock was considered to be played out. The deepest depth was struck in 18841884 is a leap year starting on Tuesday (click on link to calendar). Events January 4 The Fabian Society is founded in London. February 1 Edition one of the Oxford English Dictionary is published. March 13 The siege of Khartoum, Sudan begins (ends on Janu in the Mexican Winze at 3,300 feet below the surface. Underground mining continued sporadically until 1922Events January 7 Dali Eireann ratifies the Anglo-Irish Treaty by 64-57 votes. January 10 Arthur Griffith is elected President of Dail Eireann January 11 First successful insulin treatment of diabetes. January 12 British government releases Irish prisoners, when the last of the pumps was shut off causing the mines to flood. Re-processing of mill tailings continued through the 1920s, and exploration in the area continued through the 1950s.