Dictionnaire de la Langue Française d'Émile Littré. d'Émile Littré. 1872-1877.
Orrery — This article is about the mechanical device. For the British peerage, see Earl of Orrery. A small orrery showing earth and the inner planets An orrery is a mechanical device that illustrates the relative positions and motions of the planets and… … Wikipedia
History of longitude — The history of longitude is a record of the effort, by navigators and scientists over several centuries, to discover a means of determining longitude. The measurement of longitude is important to both cartography and navigation. Historically, the … Wikipedia
