Carl G. Barth
1860-1939
Born in Christiania, Norway, on February 28, 1860, mathematician Carl Georg Barth received his education at the Norwegian navy's technical school, at Horten. In 1881, he immigrated to the United States. There, he obtained employment at William Sellers and Company, a machine tool shop in Philadelphia.
In 1899, scientific management pioneer Frederick Winslow Taylor hired Barth to assist in his metal-cutting experiments at the Bethlehem Steel Company in Bethlehem, Pennsylvania. Barth spent the next several years developing slide rules used to determine, for a particular machine, the speed and feed settings necessary to most economically produce a specific cut. In 1902 he followed Taylor back to William Sellers and Company, where he developed similar slide rules for cutting cast iron. Barth also prepared slide rule bases for the Tabor Manufacturing Company in Philadelphia.
In 1905 Barth began work as an independent consultant. For two decades he traveled to various plants, including the United States Arsenal at Watertown, Massachusetts (1909), installing his slide rule systems. Though officially retired in 1923, Barth continued to make slide rules. In addition to feed-and-speed slide rules, Barth created slide rules for calculations related to gears, belts, helical springs, and more.
Barth taught intermittently during his career, including at the Franklin Institute of Philadelphia and the International Correspondence School of Scranton, Pennsylvania. He died in 1939.