Proportional wire chamber 185 X 50 cm; CERN Heidelberg Group for exp. S93

To continue the study of the neutral kaon with a precision greater than ever yet achieved a CERN-Heidelberg team were building an experiment which finally included three large multiwire proportional chambers. The smallest of these is shown being tested. The experiment was due to start after the next shutdown of the 28 GeV proton synchrotron and expected to record tens of millions of events.