ON SECULAR CHANGE OF GRAVITY

Abstract

Summarizing the preceding descriptions, some gravity changes were observed in the regions of negative Bouguer anomaly, especially in the eastern shore region of Lake Biwa rather prominent gravity increases were observed. But, many questions were deferred to be solved as to whether the observed gravity changes were real gravity changes or apparent ones caused by any instrumental or obser-vational errors. For the solution of these questions, generally speaking, for the investigation of the problem on secular change of gravity, it is considered to be indispensable to use portable gravimeters in combination with other measuring apparatus, for instance suitable gravity variometers and gravity pendulums. Astro-nomical observations on the change of plumb-line will give us some important informations on this problem.