J. H. Dickinson and his son S. L. Dickinson of New Jersey have been granted more than 12 patents for devices connected with player pianos. W. B. Purvis of Philadelphia was an early inventor of machinery for making paper bags. Many of his patents were sold to the Union Paper Bag Company of New York. Today the Negro is an economic factor in the United States to a degree realized by few. His occupations were thus grouped in 1920:[69] The men were employed as follows: in agriculture 1,566,627 in extraction of minerals 72,892 in manufacturing and mechanical industries 781,827 in transportation 308,896 in trade 129,309 in public service 49,586 in professional service 41,056 in domestic and personal service 273,959 in clerical occupations 28,710 The women were employed as follows: in agriculture 612,261 in manufacturing and mechanical industries 104,983 in trade 11,158 in professional service 39,127 in domestic and personal service 790,631 in clerical occupations 8,301 A list of occupations in which at least 10,000 Negroes were engaged in 1920 is impressive: MALES