b'Bouguer and the shape of the EarthFeature1757. These papers were to become useful for navigation at sea and marine explorers like James Cook and his French contemporaries benefited from them. Pierre was also good at inventing instruments such as the heliometer, and in 1748 he was probably better known as the father of photometry. In 1750 he was elected a fellow of the British Royal Society. After enduring all the health hazards of Ecuador for nearly seven years, he succumbed to the polluted water of Paris in 1758.AcknowledgmentThe author is very grateful to Larrie Ferreiro for his ready permission granted to reproduce Figures 1, 2 and 3.ReferencesAiton, E. J., 1972. The vortex theory of planetary motions. MacDonald, London. 282 pp.Bouguer, P., 1749. La figure de la Terre. Jombert, Paris.Descartes, R., 1644. Principia philosophiae, English trans. Miller, V. R. and Miller, R. P., 1983, Principles of philosophy, Kluwer Academic Publishers. Dordrecht.Ferreiro, L. D., 2011. Measure of the Earth: The enlightenment expedition that reshaped our world. Basic Books, New York. 353 pp.https://www.encyclopedia.com/people/science-and-technology/physics-biographies/pierre-bouguerFigure 4.A portrait of Bouguer at age 55, painted in 1753, which can be seenhttp://mathshistory.st-andrews.ac.uk/Biographies/Bouguer.htmlin the Louvre in Paris. Source http://arts-graphiques.louvre.fr/ https://en.wikipedia.org/wiki/Pierre_BouguerJuan J. and de Ulloa A., 1765. Relacin histrica del viajela Amrica Meridional. 2 vols. Abridged translation: Leonard the concept of mountain roots understood or the Theory ofI., 1964. A voyage to South America. Knopf Doubleday, New Isostasy to come later. York.Bouguer returned home in January 1744, after almost nineMilsom, J., 2018. The hunt for Earth gravity: A history of gravity years away, when he had not only definitive proof of the Earthsmeasurement from Galileo to the 21st century. Springer, oblateness but he had also practically verified, for the first time,Switzerland. 416 pp.Newtons theory of universal gravitational attraction. TheseNewton, I., 1687. Philosophiae naturalis principia mathematica. results were published in 1749 in La Figure de Terre,. (BouguerRoyal Society, London. trans. Bernard Cohen, I. and Whitman, 1749) which became the official account of the mission11. HeA. 1999, University of California Press, Berkeley. 974 pp.quickly became one of the most esteemed scientists in FranceRicher J., 1679. Observations astronomiques et physiques faites and later, Director of the Academy and its most prolific author.en lisle de Caienne. In History and Memoires of the Royal Figure 4 is a portrait of Bouguer at age 55, which can be seen inAcademy of Sciences of Paris, 1666-1699, vol. 7, part 1, 231-the Louvre in Paris. 326. Paris.Sheriff, R.E., 1991. Encyclopedic dictionary of exploration Bouguer continued to produce several important papersgeophysics, 3rd edn., SEG, Tulsa. 376 ppon naval architecture and navigation in 1746, 1753 and 11The Bouguer 1749 reference given is a much-shortened version of the 54 French words of the full title.43 PREVIEW OCTOBER 2020'