Gilbert Mathewson, Jr. remained with DuPont after the Civil War. By 1870 he had become one of the yard foremen. From around 1875 to the end of his employment with DuPont, Gilbert Jr. served in administrative roles at the Hagley Yard and the keg shop. He also intermittently worked for the company varnishing kegs.
Mathewson was one of 248 employees who signed a "Centennial Resolution" to the company during DuPont's one hundredth anniversary celebration in 1902. Then widowed and living with his son Thomas Walker Mathewson, Gilbert Jr. was among the longest serving DuPont employees. Gilbert and the other signers of the resolution noted that several generations of their families (including grandfathers, fathers, themselves, sons, and grandsons) had proudly worked for DuPont.
Gilbert Mathewson, Jr. retired from the DuPont Company not long after the centennial celebration. He died at his son's home in the Henry Clay community on 27 July 1904. His death certificate listed his occupation as "retired gentleman."
Image: Gilbert Mathewson, Jr., ca. 1900 (Hagley Archives)