The Pioneer 8 spacecraft (launched on December 13, 1967) first crossed the geomagnetic tail at a downstream distance of 500--800 RE as it left the Earth-moon system, and during a two-week period centered on January 23, 1968, the magnetometer, plasma probe and plasma wave instrument all detected specific tail-related phenomena. In April and May of 1985, Pioneer 8 traversed the expected position of the Earth's tail once again, at an average downstream distance of 1650 RE. For this secnd tail monitoring opportunity the available spacecraft power was so low that only the plasma wave instrument could be operated, but the electric field observations were sufficient to give unambiguous evidence of several distant tail crossings. This report contains a summary of the 1985 Pioneer 8 measurements, and a brief discussion of the limited information available on solar wind variations and terrestrial magnetic activity indicators. ¿ American Geophysical Union 1987