Résumé : A stack of nuclear emulsion pellicles of total volume 10 litres was placed, together with two spark chambers in the neutrino beam of the CERN proton synchrotron. The tracks of secondary particles from neutrino interactions in the emulsion were observed in the spark chamber. The spark chamber tracks were used to locate the tracks produced by the same particles in the emulsion. These tracks were then followed back in the emulsion to the neutrino interaction in which they originate. Of a total of seven neutrino interactions expected to be produced in the emulsion stack during this exposure four were located in this way and their characteristics studied. © 1965 Società Italiana di Fisica.