Marking Gauges, Rules, Suares
Directory of American Toolmakers Information
Though he worked in Charleston, Watts marked his tools Boston. One report of A.J. Watts, Boston, is thought to be a misrecording of the name.
Phil Platt states "Joseph Watts' working dates were 1834 - 1849 (D.A.T.) He apparently worked at rule making, making gauges and squares in Charlestown, MA.; but, marked at least the rules 'BOSTON'. There are many 'Watts' family members in and around the city of Boston. Don and Anne Wing, Marion, MA (EAIA) are currently doing research on J. Watts and trying to connect him back to English rule makers. See: Milt Bacheller, "American Marking Gages" for an extensive write up on the Watts family."
Nelson, Robert E., Ed. (1999). Directory of American Toolmakers: A listing of identified makers of tools who worked in Canada and the United States before 1900. Early American Industries Association.