Show pittsburgh students test intensity of soiled air two we pittsburgh students of soiled air set up an ingenious device that records the intensity of 0 ultraviolet or snort short wave solar radiation says say new york sun attached to the instrument ment Is a meter on which a pen draws a punctuated curved line across a check ruled page every day for a whole year such a record was taken on the roof of a building in pittsburgh the report on this collection of samples of solar handwriting has just been issued the day by day story ot of Pitts burghs share in the suns gift of ultraviolet rays 1 11 I B meller describes the loss of radiation in winter months on lays days of overcast skies sorriest of all recordings he says were those on mornings when man made smoke became mixed with fog and mantled the industrial cities |