Nicolas-Louis De La Caille, Astronomer and Geodesist : South African Astronomical Observatory

La Caille was one of the observational astronomers and geodesists who followed Newton in developing ideas about celestial mechanics and the shape of the earth. He provided data to the great 18th-century mathematicians involved in understanding the complex gravitational effects that the heavenly bodies have on one another. Observing from the Cape of Good Hope, he made the first ever telescopic sky survey and gave many of the southern constellations their present-day names. He measured the paths of the planets and determined their distances by trigonometry. In addition, he made a controversial measurement of the radius of the earth that seemed to prove it was pear-shaped. On a practical level, La Caille developed the method of `Lunars' for determining longitudes at sea. He mapped the Cape. As an influential teacher he propagated Newton's theory of universal gravitation at a time when it was only beginning to be accepted on the European continent. This book gives the most comprehensive overview so far available of La Caille's life and work, showing how he interacted with his often difficult colleagues. It places special emphasis on his life at, and his observations and comments on, the Cape of Good Hope, where he spent the years 1751-53. This is a comprehensive biography of a great observational astronomer, Nicolas-Louis de La Caille (1713-62). Though educated for the priesthood, La Caille refused to be ordained and turned instead to astronomy. Early on he was made Professor of Mathematics at the Collège Mazarin, where he propagated Newtonian ideas. He also built an observatory from which he conducted his lifelong programme of improving the positions of the bright stars and determining the orbits of the Moon and planets. At the Cape of Good Hope (1751-53) he made the first systematic telescopic sky survey and mapped the southern heavens. He defined and named many of the constellations. Making measurements simultaneously with colleagues in Europe, he determined the distances of the Sun, the Moon and the planets Venus and Mars. The information he gathered was critical to the development of the theory of planetary perturbations. He measured the radius of the earth and came to the conclusion that it is pear-shaped. He also made extensive notes on the Cape environment as well as on the colonists and slaves. In some ways rather fierce, La Caille had a serious demeanour and abhorred frivolity and dishonesty. Nevertheless, he had a small number of close friends with whom he could relax and unbend. His colleagues and former pupils loved and respected him in spite of his forbidding manner Cover 1 Contents 6 Introduction 8 1 Early life 12 2 The Cape 40 3 The shape of the earth 74 4 Notes about the Cape 91 5 Later years 120 6 Paradox resolved 157 Appendix 1 Astronomical terms 175 Appendix 2 Currency and length conversions 177 Appendix 3 Note on the Journal Historique 179 Appendix 4 Timeline 182 Appendix 5 Sources and acknowledgements 183 Appendix 6 Bibliography 186 Index 192 A 192 B 192 C 193 D 194 E 194 F 195 G 195 H 195 I 196 J 196 K 196 L 196 M 197 N 198 O 199 P 199 R 199 S 200 T 200 V 200 W 201 Z 201 This Is A Comprehensive Biography Of One Of The Greatest And Most Careful Observational Astronomers Of All Time. Nicolas-louis De La Caille Mapped The Southern Sky And Named Many Of The Constellations. In Addition, He Contributed To Geodesy, Navigation, And Celestial Mechanics. Early Life -- The Cape -- The Shape Of The Earth -- Notes About The Cape -- Later Years -- Paradox Resolved. I.s. Glass. Includes Bibliographical References And Index. This is a comprehensive biography of one of the greatest and most careful observational astronomers of all time. Nicolas-Louis De La Caille mapped the southern sky and named many of the constellations. In addition, he contributed to geodesy, navigation, and celestial mechanics.-- Source other than Library of Congress This is the first comprehensive biography of one of the greatest and most careful observational astronomers of all time. He mapped the southern sky and named many of the constellations. In addition, he contributed to geodesy, navigation, and celestial mechanics.