Gravity investigations : August 1 - October 31, 1959

Pendulum Program: During subject period Dr. Rose completed the rebuilding of the recording system for the pendulum so that visual records could be obtained with a standard oscillograph type camera. The first teat runs with this equipment showed that the accuracy of observataion was materially improved in that the period could be read with greater precision than was obtainable with the Berkeley counter direct read out system. A field run was made the last of October, which included observations at the following sites: Madison, Wisconsin Washington, D. C. Charleston, S. C. Key West, Florida Lamont Geological Observatory, N. Y. Otta, Canada Measurements were taken on a repeat basis on the return leg at each site and the reliability on the basis of a statistical analysis of the results was approximately 0.1 mgal.Contract AF19(604) 2157 with the Geophysics Research Directorate Air Force Cambridge Research Center Air Research and Development Comman