Peter of Maricourt
Peter of Maricourt
Flourished 1260s
Engineer
Experimental Method. Also known as Peter Peregrinus (the Pilgrim) of Maricourt, Peter of Maricourt was a French engineer whose De magnete (On the Magnet), written on 8 August 1269, is the first major medieval scientific-experimental treatise composed in Western Europe.
Life and Writings. Peter’s birth and death dates are unknown, and little is known about his life, except that he wrote his treatise while an engineer in the army of Charles I of Anjou during his siege of Lucerna, Italy. In De magnete, written in the form of a letter to a knight named Siger de Foucecourt, Peter castigated reliance on reason alone, stressing experimentation, manual skill, and technique as crucial to science.
Experiments with Magnetism. Peter’s work on the magnet, which was used in the Renaissance by William Gilbert in his work On the Magnet (1600), describes how to construct a magnet so that the polar north can be found. In Peter’s experiment, a needle is placed on the magnet at various points, and each time it comes to rest, a line is drawn. The results demonstrate that the meridians meet at the poles. Another of Peter’s experiments shows that a needle placed in a wooden bowl in a large container of water will invariably point north. Peter also discussed the relation of the magnet to iron and the theory of magnetic attraction and repulsion, and he suggested that magnetic instruments could provide new technologies, describing, for example, a perpetual-motion machine and the compass.
Source
Edward Grant, “Peter Peregrinus,” in Dictionary of Scientific Biography, edited by Charles Coulston Gillispie (New York: Scribner, 1970-1980), 10: 532–539.