Complex sentence: When his two sons, Thomas II and Clement, came of age, both moved north to Falmouth, Maine, (now known as Portland, Maine), around 1735, and purchased land in the Stroudwater area.
Split into simpler sentences: When his two sons, Thomas II and Clement, came of age, both moved north to Falmouth, Maine, (now known as Portland, Maine). They moved around the yesr 1735, and purchased land in the Stroudwater area.