Report on Finlay Freundlich's lecture to the Edinburgh Mathematical Society given in the Department of Natural Philosophy, Edinburgh, on Saturday 3 February 1940. This is taken from the Society's Minute Book.

Dr E Finlay-Freundlich delivered a lecture on

*The two-body problem in modern astronomy*. He described recent work on this problem for the case of 2 bodies whose dimensions are comparable with their distance apart, as occurs in practice with double stars. Theoretical prediction and observational evidence as to the divergence from a simple Kepler orbit were compared and applied to test the accuracy of models of the constitution of stars. The evidence so far obtained favoured one of Eddington's results.

Professors Greaves and Born contributed to discussion and emphasised the fact that the recent work gives a criterion for testing the constitution of stars.