Muskets and Pendulums: Benjamin Robins, Leonhard Euler, and the Ballistics Revolution

Abstract

Muskets and Pendulums: Benjamin Robins, Leonhard Euler, and the Ballistics Revolution BRETT D. STEELE Ballistics was revolutionized between 1742 and 1753 by Benjamin Robins (1707-51) and Leonhard Euler (1707-83). As one artillery officer wrote in 1789, “Before Robins, who was in gunnery what the immortal Newton was in philosophy, the founder of a new system deduced from experiment and nature, the service of artillery was a mere matter of chance, founded on no principles, or at best, but erroneous ones.”1 John Pringle, a president of the Royal Society, put it more simply in 1783 by stating that Robins created a “new science.”2John Nef wrote in 1950 that Robins’s work “provides a landmark in the interrelations between knowledge and war.”3 Two engineers more recently described him as being “one of the fathers of aerodynamics,” while Thomas P. Hughes referred to him as “a founder of modern gunnery.”4 What did Mr. Sti ei.e is in the Program for the History of Science and Technology at the University of Minnesota, writing his dissertation on 18th-century ballistics and gunnery and working on an economic theory of technological products. His research was supported by fellowships from the Smithsonian Institution’s National Museum ofAmerican History and the Deutsches Museum and by the assistance of I. S. Weissbrodt. He thanks Ed Layton, Roger Hahn, Michael Segre, Mark Levinson, Maarten Heyboer,John Jackson, Don Opitz, and the Technology and Culture referees for their helpful comments and criticisms. 'Papacino D’Antoni, A Treatise on Gunpowder; a Treatise on Fire-Arms; and a Treatise on the Service of Artillery in the Time of War, trans. Captain Thomson of the Royal Regiment of Artillery (London, 1789), p. xvii. John Pringle, Six Discourses . . . on occasion ofSix Annual Assignments ofSir Godfrey Copleys Medal (London, 1783), p. 273. John Nef, War and Human Progress: An Essay on the Rise of Industrial Civilization (Cambridge, Mass., 1950), p. 194. 4H. M. Barkla and L.J. Auchterlonie, “The Magnus or Robins Effect on Rotating Spheres,”Journal ofFluid Mechanics A7 (1971): 437. See Thomas P. Hughes’s commentary after David D. Bien’s article, “Military Education in 18th Century France: Technical and Non-technical Determinants,” in Science, Technology and Warfare: Proceedings of the 3rd Military History Symposium, USAFA, 8-9 May 1969, ed. Monte D. Wright and LawrenceJ. Paszek (Washington, D.C., 1971), p. 73. No books devoted to the history of ballistics in the 18th century exist in English at present. In other languages, however, there are some useful intellectual histories that include the subject. See M. P. Charbonnier, Essais sur© 1994 by the Society for the History of Technology. All rights reserved. 0040-165X/94/3502-0002$01.00 348 The Ballistics Revolution 349 such a seemingly obscure British mathematician and engineer do to generate such acclaim? Charles Hutton, the 18th-century artillery professor at Woolwich, said that Robins’s research represents “the first work that can be considered as attempting to establish a practical system of gunnery, and projectiles, on good experiments, on the force of gunpowder, on the resistance of the air, and on the effects of different pieces of artillery.”” More specifically, Robins invented new instruments which he used to discover and quantify the enormous magnitude of air-resistance force acting on high-speed projectiles and to make the first observations of the sound barrier. He also conducted a theoretical and experimental thermodynamic analysis of interior ballistics, discov­ ered the Magnus (or Robins) effect of fluid mechanics, and established a rational understanding of the rifling phenomenon. Of all his aerody­ namic discoveries, the enormous and complex function of air-resistance force encountered by high-speed projectiles caused the greatest sensa­ tion in the 18th century. This discovery quantitatively showed the inadequacy of Galileo’s projectile theory, which neglected air resistance, and the oversimplification ofSir Isaac Newton’s and Christian Huygens’s air-resistance theory for projectile motion. Furthermore, Robins’s airresistance experiments made the practical mathematical analysis of high-speed ballistic motion possible. Robins summarized his initial discoveries in New Principles of Gunnery, a short book that was first published in 1742?’ Euler translated this work into German and added an extensive mathematical analysis...