Spectra of compressed gases and molecular interactions

[Professor Vodar was prevented from reaching London in time for the meeting, and his paper was received shortly afterwards.] In this paper a few recent results (experimental and theoretical) are given concerning the spectra of compressed gases, which are more or less directly related to the effect of the environment on the molecular levels. Some of these results deal mainly with the problem of induced intensity, and not of energy level shifts, and other data id concern atomic spectra but are quoted here since in these cases the active atom and I the perturber have to be considered as a pair during the perturbation process. The following co-workers are associated with the work reported here: R. Bergeon, R. Coulon, L. Galatry, B. Oksengorn, J. Robin, F. Schuller and Vu-Hai.