opened trade good stores in Carson City and Silver City. Being reportedly slow mentally, having no education and no business experience, he went broke. After losing nearly all his property and possessions in Nevada, Comstock prospected for some years in Idaho and Montana without success. In September 1870, while in Bozeman, Montana, he died of a gunshot wound, believed to be a suicide. Innovations and development Mining 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. Sometimes, 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 rock resulted in frequent and deadly cave-ins. The excavations were carried to depths of more than 3,200 feet (1,000 m) (eventually, after years of work). The cave-in problem was solved by the method of square set timbering invented by Philip Deidesheimer, a German mining engineer from San Francisco, who had been requested to survey the problem by the owners of the Ophir Mine. Previously, timber sets consisting of vertical members on either side of the diggings (ribs) capped by a third horizontal member to support the back (roof), creating a tunnel (drift). However, the Comstock ore bodies were not veins, but sporadic pockets too large for this method. Instead, as ore was removed it was replaced by timbers set as a cube six feet on a side (ribs), front (face) or top (back), all at the same time. Thus, the ore body would be progressively replaced with a timber lattice. Often these voids (stopes) would be re-filled with waste rock from other diggings after ore removal was complete. By this method of building up squares of framed timbers, an ore body of any width may be safely worked to any height or depth. Deidesheimer was appointed to the Ophir as mine manager for his ingenious idea. Early in the history of Comstock mining, there were heavy flows of water to contend with. This called for pumping machinery and apparatus, and as greater depth was attained, larger pumps were demanded. All the inventive genius of the Pacific Coast was called into play, and this resulted in construction of some of