CONTENTS Part One. Theoretical Principles of Gravity Procedure Basic Concepts of Gravity Measurements The Normal Gravitational Field and the Figure of the Earth Reduction of Gravity Values Change of Gravity with Time. Tides Part Two. Measurement of Gravity Principal Methods of Determining Gravity Pendulum Apparatus Gravimeters Procedure for Making Observations with Gravimeters Torsion Balances and Gradiometers Gravity Measurement at Sea Part Three. Techniques of Gravity Surveying The World Gravity Network Procedure of Gravity Surveying and the Processing of Survey Data Part Four. Geological Interpretation of Gravity Anomalies Theory of Isostasy and Structure of the Earth's Crust Geological Interpretation of Gravitational Fields Delineation of Gravitational Fields Methods of Solving Direct and Reverse Problems of Gravity Prospecting