John Harrison designed one of these for ships, thus winning a 20,000 pound prize offered by the British Government. That device enabled better calculation of Longitude. Ctesibius improved on the Greek version called a clepsydra, which used water. Christiaan Huygens invented a pendulum one, while a Foucault pendulum can also be used as one. In 1955, one using cesium was invented. That is an atomic one, which are the most a
John Harrison designed one of these for ships, thus winning a 20,000 pound prize offered by the British Government. That device enabled better calculation of Longitude. Ctesibius improved on the Greek version called a clepsydra, which used water. Christiaan Huygens invented a pendulum one, while a Foucault pendulum can also be used as one. In 1955, one using cesium was invented. That is an atomic one, which are the most accurate. For 10 points, name these machines that can tell one the time.
John Harrison designed one of these for ships, thus winning a 20,000 pound prize offered by the British Government.
{clock} [or {chronometer}]