THERE WOULD BE several advantages in driving a tunnel into Tioga Hill to cut the Sheepherder and Great Sierra lodes, the mining experts said. A tunnel would cut the veins at depth and in a zone of greater richness than on the surface. Water could be drained out through a tunnel, and ore and waste rock could be removed with the greatest efficiency. By striking the lodes at right angles the ore could be worked in both directions as well as upward. There was no difficulty in convincing the Board of Directors that this was the logical plan of operation:

November 12, 1881 — The Great Sierra Mining Company of Tioga District had advertised for sealed proposals for running a double track tunnel or adit 500 feet into Tioga Hill, the tunnel to be nine feet wide, six feet high in the clear at the walls, and seven feet in the arch. The Tunnel will be started in the cove at the head of the south fork of Lee Vining Creek and driven for the Lake and Sonora locations now being prosecuted. . . . ²² The Sheepherder lode will be cut by the adit in the Sonora location, near the Lake at a distance in of 1765 feet and at a vertical depth of 751 feet, and the Great Sierra lode will be cut in the Bevan, near the Hancock, at a distance of 2675 feet and vertical depth of 830 feet. . . . ¹⁷

November 19, 1881 — U. S. Deputy Mineral Surveyor H. B. Carpenter returned from Tioga on Sunday, having completed survey for the double track tunnel from the cove at the head of the south branch of Lee Vining Creek to the Sheepherder lode.²³

February 25, 1882 — T. Jeff McClelland, the new foreman, took over twelve miners and a blacksmith on Tuesday last and commenced work on the tunnel Wednesday morning. The hand work will be pushed by three 8-hour shifts. . . . An assay made recently at the chemical laboratory of Wm. D. Johnson, San Francisco, of ore taken from the 15-inch vein in the face of the west crosscut, 100-foot level of the Great Sierra shaft, gave a trace of gold and $438.60 per ton in silver. . . . ²⁴ Thus was started the Great Sierra Tunnel, destined to be driven 1784 feet in a test of men and metal before the collapse of the Great Sierra Consolidated Silver Company.

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