Richard Payne Knight of Downton Castle in Herefordshire, and of 5 Soho Square, London, England, was a classical scholar, connoisseur, archaeologist and numismatist, best known for his theories of picturesque beauty and for his interest in ancient phallic imagery. He served as a Member of Parliament for Leominster (1780–84) and for Ludlow (1784–1806).
The version of this that I read was titled "Two Essays on the Worship of Priapus" and is on Aleister Crowley's recommended reading list for his students.