Jacob Diffenbacher first appeared in the Pittsburgh city directory in 1863, when he boarded at 162 Lacock Street in Allegheny. The directory did not indicate Diffenbacher’s occupation.
In 1864, Diffenbacher was listed as owner of a bung (stopper or cork) factory at the corner of Market Street and Duquesne Way in Pittsburgh. Diffenbacher lived at 327 Rebecca Street in Allegheny. The 1865 directory listed Diffenbacher as a partner in Diffenbacher & Watson, dealers in oil lands, and living in New York. Diffenbacher’s partner in this venture was Henry Watson, who boarded on Resaca Place near the gas works in Allegheny.
In 1866 and 1867, Diffenbacher was a partner with John F. Glosser of 21 Diamond Street in Allegheny in a grocery store located at 21 Diamond Street. Diffenbacher lived at 327 Rebecca Street (now Reedsdale Street) in Allegheny.
In 1870 the directory listed Diffenbacher as a publisher who lived and worked at 68 Fifth Avenue in Pittsburgh. Diffenbacher moved to Emsworth in the early 1870’s, and maintained an office on Fourth Avenue. The 1874 city directory indicated that Diffenbacher was publisher of the Pittsburgh Official Railway Guide. Diffenbacher began publishing the Pittsburgh city directory in addition to the railway guide by the late 1870’s.
Neither the 1870 or 1880 censuses provide information on Jacob Diffenbacher. The 1890 census, which would provide information on Diffenbacher, was destroyed in a fire following its completion.
City directories listed Diffenbacher as living in Emsworth until 1893, when he was listed at 78 Beech Avenue for the first time. Diffenbacher was listed in the directory at 78 Beech Avenue through 1897.
Jacob Diffenbacher died at Western Pennsylvania Hospital for the Insane at Dixmont on April 1, 1898. Susan Diffenbacher was listed as a widow living at 78 Beech Avenue beginning in 1898.
Current house numbers on Beech Avenue and nearby were used beginning in 1900.
The 1900 manuscript census reported that Susan Diffenbacher, 57, lived at 843 Beech Avenue with a niece, Elizabeth Hale. Susan Diffenbacher had been married 34 years and had no children. She had no occupation.
Elizabeth Rale, 27, was single and had no occupation. She had been born in Virginia to parents also born in Virginia. City directories listed Susan Diffenbacher at 843 Beech Avenue through 1904, the year after she sold the house. She lived in the Buckingham Apartments at Craft Avenue and Kennett Square in Oakland in 1905. She lived at 3604 Forbes Avenue in Oakland in 1906, the last year that she appeared in the directory.