[3] He derived a huge income from his copper mines at Chacewater and Gwennap where he was the principal landowner.
[4] The Chacewater mine, now known as Wheal Busy, was located in what was known at one time as "the richest square mile on Earth".
[7][8] He was a colonel of the Militia from April 1660 to 1680, and a commissioner for oyer and terminer on the western circuit in July 1660.
[8] Boscawen was very active in all the parliaments in which he sat, and as a strong Protestant was considered the "great pillar of the presbyterians".
They had eight sons, all of whom predeceased their father, and two daughters, only one of whom survived, becoming his sole heiress:[1] Most of his Cornish Estates, including the family seat at Tregothnan, passed to his nephew, Hugh Boscawen, 1st Viscount Falmouth.