Epicyclic gearing - Invention: In the 2nd-century AD treatise Almagest, Ptolemy utilized turning deferent and epicycles that Makes epicyclic gear trains to foresee the movements of the planets. Precise expectations of the development of the Sun, Moon and the five planets, Mercury, Venus, Mars, Jupiter and Saturn, across the sky assumed that each followed a trajectory traced by a point on the planet gear of an epicyclic gear train. This curve is called an epitrochoid. Richard of Wallingford, an English abbot of St Albans religious community is credited for reevaluating epicyclic designing for an astronomical clock in the 14th century. In 1588, Italian military engineer Agostino Ramelli invented the bookwheel, a vertically-revolving bookstand containing epicyclic gearing with two levels of planetary gears to maintain proper orientation of the books How Does Epicyclic gear Work? The Next Video will illustrate : - How does Epicyclic gear Work - some Application of Ep