In 1818 Mason’s surname became Washington [NHNameChange24].
He moved to Mass in 1835 and in 1853 was calling himself Mason Davis, a soap manufacturer, living in Cambridge Mass [SonsNH212].
He m. in Cambridge Mass 16 Nov 1843 Caroline Harriet Teel [CabridgeMAVR2:112].
For the 1880 census he was still in Cambridge Mass living with wife Harriet b ca 1816, his daughters Carrie, b. ca 1855 and Sarah, b. ca 1857, wife of William Saul and two small grandsons.