Playfair, John, Scotch mathematician, born at Benvie; bred for the Church, became professor first of Mathematics and then of Natural Philosophy at Edinburgh University; wrote on geometry and geology, in the latter supported the Huttonian theory of the earth (1748‒1819).
Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)
Plautus * Pleiades