Pendulum the pendulum could be used to measure the force of gravity. During his expedition to Cayenne, French Guiana in 1671, Jean Richer found that a pendulum clock was minutes per day slower at Cayenne than at Paris. From this he deduced that the force of gravity was lower at Cayenne. In 1687, Isaac Newton in "Principia Mathematica" showed that this was because the Earth was not a true sphere but slightly oblate (flattened at the poles) from the effect of centrifugal force due to its rotation, causing gravity to increase with latitude. Portable pendulums began to be taken on voyages
SS City of Manchester (1851) built 1935, sunk 28 February 1942 by Japanese submarine I-153 off Java 6. "City of Manchester", built 1950, sold 1971 and renamed "Kavo Yerakes" 7. "City of Manchester", so named 1984-1985, before and after named "Hassel Werder". SS City of Manchester (1851) The SS "City of Manchester" was an iron-hulled single screw liner built 1851 by Tod & McGregor, Glasgow, Scotland and the second such ship owned by the Inman Line (officially the Liverpool and Philadelphia Steam Ship Company). It was an improved version of their first ship "City of Glasgow" which had been launched a year earlier. Steerage passengers