Autograph Letter Signed, to Professor Royle [Dr. J.Forbes Royle, the naturalist], about an acquaintance coming from India, a visit to London, etc. 3 pp. 5 x 3 inches, fine. Leintwardine [Herefordshire], 31 September 1845. Colonel John Colvin (1794-1871), Bengal Engineers. By the time he left Calcutta he had completed 27 years service and fought two battles, introduced American cotton to Bengal and earned the title Father of Indian Irrigation.