Details of the gravity survey and area covered are outlined and an interpretation given together with notes on the magnetic survey and a report on the Chertsey Bore. This survey covered an area of about 2600 miles and the station spacing was such as to average about one station per square mile. The present report is intended to give a preliminary idea of the results of this survey, with particular reference to one or two localities where the structural conditions might be favourable for the accumulation of oil in commercial quantities.