A translation into English has been made by Silvanus P. Thompson ("Epistle of Peter Peregrinus of Maricourt, to Sygerus of Foucaucourt, Soldier, concerning the Magnet", [London: Chiswick Press, 1902]); by Brother Arnold [=Joseph Charles Mertens] ("The Letter of Petrus Peregrinus on the Magnet, A. D. 1269", with introductory note by Brother Potamian [= M. F. O'Reilly], [New York, 1904]); and H. D. Harradon, ("Some Early Contributions to the History of Geomagnetism - I," in Terrestrial Magnetism and Atmospheric Electricity [now Journal of Geophysical Research ] 48 [1943], 3-17 [text pp. 6–17]).