early attempt to test Einstein's general theory
(EINSTEIN, ALBERT.) FREUNDLICH, ERWIN. Die Grundlagen der Einsteinschen Gravitationstheorie. Mit einem Vorwort von Albert Einstein
Berlin: Springer, 1916
Original wrappers. Very good.
FIRST EDITION. This work on Albert Einstein’s theory of gravitation contains a foreword by Einstein. Freundlich is best known for his attempts to experimentally test the general theory of relativity using astronomical observations based on the gravitational redshift.
Freundlich worked as an assistant at the University Observatory in Berlin at the time he published this work. In 1920 he moved to the Astrophysical Observatory in Potsdam, where he was director from 1921-33