A cloud chamber experiment is described, in which the angular distribution of secondary particles produced in nuclear interaction by high energy cosmic ray particles with paraffin has been studied. Sixty-four ns≥4 events with average primary energy of 70 BeV have been analysed. The result shows that, in this energy region, the angular distribution in CMS is not isotropic but possesses maxima in the 0° and 180° directions; furthermore, there is already an appreciable fraction (≥20%) of the events with angular distribution exhibiting the features given by the "fire-ball" model.