Hi,Nancy, although there were a bevy of Mason families in Swansea, Mass in 1700's--1800's, many moved to Bristol Co., Rhode Island, NY towns before they had Ohio land grants. I just endured two weeks of checking for my Swansea Masons who moved to Fort Washington,NY, another NY town, and Ohio before Gggggrandma stayed in Mo.
There were a total of eight Willam Masons born before 1817 in Swansea, Fall River, Bristol Co.Ma., and Warrington, RI. which is not too far from Swansea. FAMILYSEARCH.ORG has them listed, and please don't try the Sampson Mason line in Swansea,as most of sons are named Nathan. Good luck.LD=