Gravity, Acceleration of

The velocity imparted to a body in one second by the action of gravitation at any standard point upon the earth's surface in a vacuum. This will vary at different places, owing principally to the variation in centrifugal force due to the earth's rotation. For standard valuation it must be reduced to sea level. The following are examples of its variation: Equator, 978.1028       centimeters per second Paris, 980.94 " Green wich 981.I7 " Edinburgh, 981.54 " Pole (N. or S.),  983.1084 (theoretical)   " As round numbers for approximate calculations 981 centimeters or 32.2 feet may be employed. [Transcriber's note: The acceleration of gravity at the equator is also reduced by the increased distance from the center of the earth (equatorial bulge). Increased altitude reduces gravity. Reduced air density at altitude reduces buoyancy and increases apparent weight. Local variations of rock density affects gravity.]