From the OHS PC Database, derived from A Guide to North American Organbuilders by David H. Fox (Organ Historical Society, revised ed. 1997). —
Herman [Henry] Heinrich Holtkamp was born in 1858 in New Knoxville, Ohio; he was the father of Ferdinand, Mary, and Walter Holtkamp Sr.
He attended Calvin College; he later operated a music and piano store in St. Mary's, Ohio; he was a representative of the Votteler firm in Cleveland Ohio, 1903; he became a partner with Henry B. Votteler and Allen G. Sparling in Votteler-Holtkamp-Sparling firm of Cleveland, Ohio, c. 1914. He sold Votteler-Holtkamp-Sparling organs under name of St. Mary's Pipe Organ Co. Herman Holtkamp died March 16, 1931 in Minot, North Dakota.
Patent #1,100,568; June 16, 1914; pneumatic action.
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