John William Mackay (November 28, 1831 – July 20, 1902) was an Irish-American industrialist. Mackay was one of the four Bonanza Kings, a partnership which capitalised on the wealth generated by the silver mines at the Comstock Lode. He also headed a telegraph business that laid transatlantic cables and he helped finance the New York, Texas and Mexican Railway Company. Life and career Early years John William Mackay was born in Dublin to a working-class family. They had a dirt floor hovel shared with a pig. In 1840, the family emigrated to the notorious Five Points slum in lower Manhattan; his father died soon after. As a boy Mackay hawked newspapers such as the New York Herald, and later apprenticed at William H. Webb Shipyard to support his mother and sister. Gold and silver mining In 1851, he sailed by clipper around the Horn to California and worked eight years in placer gold fields in Sierra County without much success. In 1859, he went to Virginia City, Nevada, site of the recently discovered Comstock Lode, and there began work at $4 a day laboring in a mine by day and working his own small claims in his spare time. He bought small claims or "feet" and used the proceeds of his labor and finds to buy more feet. In 1865 he used his savings to buy into the Kentucky mine and hit big, he was suddenly worth US$1.6 million, more than enough to retire for life. He then began investing in other mines, sometimes risking everything he had. He formed a business partnership with fellow Irishmen James Graham Fair, James C. Flood, and William S. O'Brien, later known as the Bonanza Kings. The four dealt in mining stocks and operated silver mines, and had a success in the Hale & Norcross mine. In 1871, using proceeds from the Hale & Norcross they bought out a number of smaller mine claims under the name of the Consolidated Virginia Mining Company, and later added the nearby California mine. In 1873, the Con Virginia made the greatest ore body discovery ever found in North America, known as the "Big Bonanza". The strike would pay out US$181 billion in current dollars, with Mackay's portion being about $50 billion. The bonanza was in a location previously overlooked and outside where other strikes had been found. The four-way partnership was more commonly known as the "Bonanza