http://adsabs.harvard.edu/abs/2010AAS...21530404H "In January 1924 Arthur Eddington wrote to Walter S. Adams at the Mt. Wilson Observatory suggesting a measurement of the "Einstein shift" in Sirius B and providing an estimate of its magnitude. Adams' 1925 published results agreed remarkably well with Eddington's estimate. Initially this achievement was hailed as the third empirical test of General Relativity (after Mercury's anomalous perihelion advance and the 1919 measurement of the deflection of starlight). IT HAS BEEN KNOWN FOR SOME TIME THAT BOTH EDDINGTON'S ESTIMATE AND ADAMS' MEASUREMENT UNDERESTIMATED THE TRUE SIRIUS B GRAVITATIONAL REDSHIFT BY A FACTOR OF FOUR."
http://www.gravityresearchfoundation.org/pdf/awarded/1979/hetherington.pdf "...Eddington asked Adams to attempt the measurement. (...) ...Adams reported an average differential redshift of nineteen kilometers per second, very nearly the predicted gravitational redshift. Eddington was delighted with the result... (...) In 1928 Joseph Moore at the Lick Observatory measured differences between the redshifts of Sirius and Sirius B... (...) ...the average was nineteen kilometers per second, precisely what Adams had reported. (...) More seriously damaging to the reputation of Adams and Moore is the measurement in the 1960s at Mount Wilson by Jesse Greenstein, J.Oke, and H.Shipman. They found a differential redshift for Sirius B of roughly eighty kilometers per second."