Career
He was brought up as a Quaker. Removing from Maryland to Sussex county (now part of the state of Delaware) on the Delaware, he was sent to the legislature from the latter place in 1693, and again in 1701, and was chosen sheriff in 1695. In 1708 he was unanimously elected alderman.
Almost immediately afterward, Preston was called to the council, on which he served until he died.
He was chosen mayor of Philadelphia in 1711, and in 1714 became the treasurer of the province, retaining the office until his death. In 1726 he became a justice of the peace and of the court of common pleas, and in 1728 one of the commissioners of property, which office he held many years.
He was also one of the trustees under Penn"s will.