Some remarkable pictures of the Alps taken from the Puy du Dome and the Vosges at great distances appear in La Montagne for June, 1933. Mont Blanc at a distance of 305 km. and the Bernese Alps at distances of 180-230 km. among others. These pictures were taken on ordinary plates with heavy filters in contradistinction to the work of Major Stevens of the U. S. Army Air Corps, whose remarkable photographs on infra-red plates up to distances of over three hundred miles have attracted so much attention lately. The discussion of visibility at great distances has been continued in the February, 1934. number of the same periodical and the theoretical limits of visibility by the different colors is here given: Ultra-violet (by photography), 80 km.; blue, 150 km.; green, 250 km.; yellow, 300 km.; red, 500 km.

These distances naturally are shortened in actual practice by haze. A number of observations are given of mountains seen at tremendous distances and a plea made for more observations. We would like to repeat that plea here for, with the exception of Mr. E. G. Chamberlain whose panoramas from viewpoints in Massachusetts and New Hampshire are well known, very little work has been done in that direction in this country.