This year the Royal Society celebrates the third centenary of its foundation. In this paper Sir Harold Spencer Jones, the late Astronomer Royal, who was the Institute's first President, describes the early years of the Society and shows how closely some of its work was related to navigation.

For some two thousand years, until well into the seventeenth century, the writings of the ancient Greek philosophers, and in particular those of Aristotle, were regarded as the supreme fountain of wisdom and the source of all knowledge. The break with the Aristotelian dogma may be said to have started with the publication by Copernicus in 1543 of his De Revolutionibus Orbium Coelestium whereby the Earth was displaced from proud position as the centre of the Universe, fixed and immovable, and asserted to be not only rotating around an axis but also to be merely one of a system of planets revolving around the Sun as a centre. Copernicus had refrained for thirty years from publishing his theory as he knew that it would be received with ridicule, not merely because it was not in accordance with Aristotelian dogma but also because it would be held to be against the Scriptures. The Copernican theory met, in fact, with widespread opposition and more than a century elapsed before it came to be generally accepted; for long it was regarded as merely a convenient mathematical representation of the motions of the planets without any true physical basis.