be hoped. We have improved measurements by at best a factor of 3. So thIS paper, unfortunately, IS really a status report rather than a progress report. There are, however, a few new results to mention. I shall present the results wIthout glVlng any detaIls of the experImental apparatus. In general, sources of error and problems in these measurements are not determined by the apparatus itself. The most important new result IS that of Paul Henry (1971),...