Inertia-Balance-RVFM-PH10587-P-An-apparatus-for-investigating-the-nature-of-mass-&-the-distinction-between-mass-&-weight-The-device-allows-the-measurement-of-inertial-mass-as-opposed-to-gravitational-mass-for-a-regular-balance-P-P-The-principle-of-operation-is-to-record-the-oscillations-produced-when-the-tray-is-deflected-then-released-The-frequency-of-vibration-will-depend-on-the-unknown-mass-in-the-tray-being-higher-for-a-lower-mass-&-lower-for-a-higher-mass-The-object-to-be-