Dr John Percy (1817–89) was a metallurgist, the author of the four-volume A Treatise on Metallurgy, and an amateur artist who collected watercolours, drawings and prints. Sales of his drawings were held at Christie's in 1890 (15–18 and 22–24 April 1890) and sales of his prints took place at Sotheby’s in the same year (12–13 May 1890). The former included thirty-five items by or attributed to Girtin (Exhibitions: Christie's, 17 April 1890; Christie's, 23 April 1890). The informative catalogue he compiled of his collection is in the Library of the Department of Prints and Drawings at the British Museum (Percy Catalogue).