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Men of Tribology MEN OF TRIBOLOGY by DUNCAN DOWSON2 4 CHARLES AUGUSTIN COULOMB (1736-1806) 5 ARTHUR-JULES MORIN (1795-1880) 4 Downloaded from http://asmedigitalcollection.asme.org/tribology/article-pdf/100/2/148/5796303/148_1.pdf by guest on 27 September 2021 CHARLES AUGUSTiN COULOMB (1736-1806) ". / was often in the situation of discovering how much all the theories, founded upon hypotheses or upon experiments carried out in miniature in a cabinet de physique, were insufficient guides in practice." Charles Augustin Coulomb, 1781 (Archives de la Guerre, Vincennes, Dossier Coulomb). Biography in Montpellier, but the need to earn a living caused him to enter the Charles Augustin Coulomb was born on June 14th 1736 in Angou- School of Military Engineering or Ecole du genie at Mezieres. He leme in the Angoumois and he was baptized in the parish church of passed the entrance examination administered by the abbe Charles St. Andre on June 16th. His family had been prominent in law and Camus after studying in Paris for about nine months and prepared administration in Languedoc and had lived for several generations to enter the Ecole du genie early in 1760. in Montpellier. Charles Augustin's father, Henry Coulomb, first Coulomb graduated from the Ecole du genie with the rank of served in the military and then accepted a minor administrative post lieutenant en premier on November 12th 1761. The course was a with the grand title of Inspecteur des Domaines du Roi. His mother, mixture of theory and practice, with three days of each week being Catherine Bajet, was related to the wealthy de Senac family. devoted to each activity. Coulomb finished high in his group of eight Early in Charles Augustin's childhood the family moved to Paris graduates, but not all the reports on his work engendered confidence where Henry was involved in the tax-farm system. Catherine was most in his future as a military engineer. Stewart-Gillmor (1971) has re­ anxious that her son should study medicine and she arranged for him corded that the commandant Chastillon reported; to attend lectures at the College des quartre-nations. The college, . "M. Coulomb is from the Academy of Montpellier. His conduct- established by the will of Cardinal Mazarin in 1661, normally received is good, he understands and executes drafting rather well. His siege the sons of... prominent residents who live like nobles ... between memoir is worse than average, very bady portrayed, with erasures the ages of ten and fifteen years. It had a good reputation for the and jottings. It is carelessly done and employs incorrect nomen­ teaching of mathematics, d'Alembert and Lavoisier having studied clature. there, and it is clear that Coulomb developed a liking for the subject . He has a certain intelligence, but not that which will make him about this time. He moved to the College royal de France, where advance in the Corps." Pierre Charles Le Monnier presented his lectures on mathematics, Coulomb's first posting was to Brest, where he was charged with and soon produced a rift in the family by announcing that he wished minor mapping tasks on the coast between Brest and La Rochelle. to be a mathematician and not a doctor. In the meantime Henry This was during the seven years war between England and France Coulomb had engaged in financial speculations which had left him (1756-1763), and the return of Martinique to France after the Treaty penniless and he returned to Montpellier whilst the family remained of Paris in 1763 caused Coulomb to be moved from Brest to Port Royal in Paris. Charles Augustin steadfastly defied his mothers desire that to assist with the reconstruction of the islands fortifications. He sailed he should study medicine, and feelings were so strong that he was from Brest to the West Indies in the Brillant in February 1764. In due forced to return to his father in Montpellier after being temporarily course he was put in charge of the construction of Fort Bourbon on disowned by his mother. His stay in Montpellier proved to be intel­ Mount Garnier, one of the two peaks dominating the entrance to Port lectually rewarding and formative. He became a student member or Royal. He was twenty seven years old when he arrived in Martinique, membre adjoint of the Societe royale des sciences de Montpellier and during the next eight years he gained valuable and varied field at the age of twenty one and presented two mathematical and three experience. In due course much of this experience was to be distilled astronomical memoirs during his subsequent sixteen month mem­ and presented in the form of memoirs on statics, architecture and the bership. Mathematics was his chief interest during this brief period efficiency of labouring men to the Academy of Sciences in Paris. The Corps was plagued with illness, during the construction of Fort Bourbon and Coulomb became seriously ill on numerous occasions. When he left Martinque in the June of 1772 his health had deterio­ 1 Based upon a series of biographical sketches of "Men of Tribology" from a forthcoming book The History of Tribology to be published early in X978 by rated considerably. Longman Group Limited, Longman House, Burnt Mill, Harlow, Essex, England. On his return to France, Coulomb was posted to Bouchain where American enquiries to Longman Inc., 19 West 44th Street, New York, N.Y. he found time to write about his work and experiences in the West 2 Professor of Engineering Fluid Mechanics and Tribology, Institute of Tribology, Department of Mechanical Engineering, The University of Leeds, Indies. His "Essay on an Application of the Rules of Maxima and England. Minima to Some Problems in Statics Relating to Architecture" was 148 / VOL 100, APRIL 1978 Copyright © 1978 by ASME Transactions of the ASME Downloaded from http://asmedigitalcollection.asme.org/tribology/article-pdf/100/2/148/5796303/148_1.pdf by guest on 27 September 2021 Photograph of portrait of Charles Augustin Coulomb. Reproduced by permission of Mr. C. A. Coulomb, Jr., Coulombs' great-great-grandson, Longmeadow, Mass., U.S.A. r<'ad before the Academy in Paris in February and March of 1773. The prize which had initially been announced by the Academy of Sciences wide ranging essay was well received and Coulomb was appointed in Paris in 1777. This was his second and consecutive success in the f!ossut's correspondent to the Paris Academy of Sciences on July 6th naval prize contests of the Academy. Shortly afterwards he requested 1774. In the same year he was posted to Cherbourg for a two year tour a posting in Paris to enable him to pursue his interests in the Acade­ of duty and it was whilst he was at La Hougue, near Cherbourg, that my. He moved in September, was awarded the Croix de Saint Louis h<' completed his important essay on "Investigations of the Best on September 30th and elected to the Academy of Sciences on De­ Method of Making Magnetic Needles." The Academy of Sciences had cember 12th 1781. These hectic events late in 1781, when Coulomb announced a competition for the best means of constructing magnetic was forty five years old, marked a transition from his earlier career compasses, with the prize being offered in 1775. No winner was se­ in engineering to his later career in physics. Few men have changed I<'cted in 1775 and the prize was therefore doubled in 1777. Coulomb disciplines so effectively half-way through their professional lives. shared the doubled award with J. H. Van Swindon. Stewart Gillmor The move to Paris in 1781 provided Coulomh with an established (1 D71) has drawn attention to the fact that this particular memoir, home for the first time in many years. Military Service and transfers written by Coulomb the engineer, contained all the elements, in­ to new locations every two years or so prevented the establishment cluding friction, of Coulomb's subsequent major contributions to of a permanent laboratory facility. On the other hand it exposed physics. Coulomb to a wide range of problems in engineering and physics and Coulomb's next posting was to Besancon in 1777 and it was in­ he clearly responded to the challenge. He investigated architecture I ended that he should move to Marseilles in 1779. His father had died and construction in Martineque, friction in Rochfort, coastal defences during his service in the West Indies, but his mother survived until in Cherbourg and windmills in Lille. In Paris his studies were directed 1779. Charles Augustin shared the inheritance with his sisters as a more towards physics and he became active in the Academy. Academy result of a reconciliation following the strained relationship which membership brought its share of administrative work and Coulomb arose over the question of his early career. It is not clear whether he was an active committee member. He became involved in committees <'vel' went to his post in Marseilles, but he certainly spent some time dealing with hospital reform, weights and measures and water pumps. in Paris attending to his mothers estate. He also read a paper to the He was a member of the Academy's Library Committee and on March Academy in May 1779 on the subject of dredging machinery. 19th 1783 he became the first person in France to describe publicly In May 1779 Coulomb served in the Brigade of Toulon at Mar­ the principle of the Boulton and Watt improved (condensing) steam seilles, where he he was involved in the construction of a fort near engine developed across the English channel. He nevertheless found j{ochefort. Itwas here that he undertook his extensive studies of fric­ time to read thirty two scientific memoirs to the Academy and its I ion and in the spring of 1781 his extensive essay entitled "Theorie successor the Institut de France between 1773 and 1806.
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