Benjamin Williamson (1827–1916) was an Irish mathematician who was a Fellow of Trinity College Dublin (TCD) for over 60 years and was Professor of Natural Philosophy there from 1884 to 1890.^[1][2]

Williamson was born in Mallow, County Cork, son of the Rev Benjamin Williamson. He attended Kilkenny College. At TCD he was awarded BA (1849) and MA (1855), having become a Fellow in 1852. He was Donegall Lecturer in Mathematics (1876–1884), and then Professor of Natural Philosophy (1884–1890).^[1][2] TCD awarded him a DSc (1891) and Oxford a DCL (1892). He later became vice provost of TCD (1908), and died in Dublin.^{[citation needed]}

His two calculus books were very popular and ran into many editions over the 40 years following their publication.^[3]

• 1872 An Elementary Treatise on the Differential Calculus, Containing the Theory of Plane Curves, With Numerous Examples
• 1874 An Elementary Treatise on the Integral Calculus, containing applications to plane curves and surfaces
• 1884 An Elementary Treatise on Dynamics, containing applications to thermodynamics, with numerous examples (co-written with F. A. Tarleton)
• 1894 An Introduction to the Mathematical Theory of Stress and Strain of Elastic Solids