Abstract
There is a distinct deference between American and European opinions about the most suitable beam pattern of motor-car headlights. The American point of view has been published in the Annexe to the Report 23b of the I.C.I. 1939 by H.M. Magdsick entitled: Some factors governing visibility distances with motor-car headlights. From visibility tests Magdsick and his collaborators concluded that the beam pattern realized in the sealed beam lamps should be superior to that of the European headlamps. In those tests a man size pedestrian dummy was taken as the visibility object. The visibility of the object was considered to be sufficient even if the object or only part of it could be discerned by silhouette.