The grandfather of Tobias Smollett. He sat on a variety of parliamentary commissions and committees; however, his most important position was the commissioner for union with England, first in August 1702, and more successfully in February 1706. He helped frame the articles of the union, and in 1707 was the elected member for Dunbartonshire to the first parliament of the United Kingdom of Great Britain. His manuscript Memorials of Certain Passages of the Lord's Signal Mercies provide his comments on the affairs of the time.