[2] Besides editing two works by his cousin, Roger Cotes, who was his predecessor in the Plumian chair, he published A Compleat System of Opticks in 1738, which gained him the sobriquet of Old Focus, and Harmonics, or the Philosophy of Musical Sounds in 1749.

Smith never married but lived with his unmarried sister Elzimar (1683–1758) in the lodge at Trinity College.

Although he is often portrayed as a rather reclusive character, John Byrom's journal shows that in the 1720s and 1730s Smith could be quite sociable.

Yet ill health, particularly gout, took its toll and severely inhibited his academic work and social activities.

The net income on the fund is annually divided equally between the Smith's Prize and the stipend of the Plumian Professor.