Geocentric model the coordinate system in order to predict the motions of planetary bodies, though doing so may make calculations easier to perform or interpret. A geocentric coordinate system can be more convenient when dealing only with bodies mostly influenced by the gravity of the Earth (such as artificial satellites and the Moon), or when calculating what the sky will look like when viewed from Earth (as opposed to an imaginary observer looking down on the entire solar system, where a different coordinate system might be more convenient). The Ptolemaic model of the solar system held sway into the early modern age;
What the Butler Saw (mutoscope) this feature became widely used in Britain as a generic term for devices and movies of this kind. The phrase had entered British popular culture after the 1886 divorce case of Lord Colin Campbell and Gertrude Elizabeth Blood. The trial hinged on whether their butler could have seen Lady Campbell "in flagrante" with Captain Shaw of the Metropolitan Fire Brigade, through the keyhole of their dining room at 79 Cadogan Place, London. What the Butler Saw (mutoscope) What the Butler Saw was a mutoscope reel, and an early example of erotic films dating from the early 1900s. It depicted a