PART II
A COUPLE OF CENTURIES' PROGRESS.
NOTES TO LECTURE X
Science during the century after Newton
The Principia published, 1687
| Roemer | 1644–1710 |
| James Bradley | 1692–1762 |
| Clairaut | 1713–1765 |
| Euler | 1707–1783 |
| D'Alembert | 1717–1783 |
| Lagrange | 1736–1813 |
| Laplace | 1749–1827 |
| William Herschel | 1738–1822 |
Olaus Roemer was born in Jutland, and studied at Copenhagen. Assisted Picard in 1671 to determine the exact position of Tycho's observatory on Huen. Accompanied Picard to Paris, and in 1675 read before the Academy his paper "On Successive Propagation of Light as revealed by a certain inequality in the motion of Jupiter's First Satellite." In 1681 he returned to Copenhagen as Professor of Mathematics and Astronomy, and died in 1710. He invented the transit instrument, mural circle, equatorial mounting for telescopes, and most of the other principal instruments now in use in observatories. He made as many observations as Tycho Brahé, but the records of all but the work of three days were destroyed by a great fire in 1728.