Perhaps his most difficult subjects to capture on film were the lightning bolts Jennings succeeded in photographing in 1882. The Franklin Institute recognized him for this feat with the Wetherill Medal in the 1930s, in honor of his work's contribution to the advancement of physical science. Jennings himself was a dedicated member of The Franklin Institute throughout his life, publishing articles in its Journal, giving presentations within its walls, and sitting on its Boards. When the Secretary of The Franklin Institute sent word to Jennings congratulating him on his achievement, he alluded to Jennings' commitment to The Franklin Institute itself as well as to the advancement of science: "How appropriate it seemed that we should try to pay honor to you."
You can read the full text of this letter, along with the report which was enclosed with it, by clicking on the thumbnails at right. This report "recommended the award of the Wetherill Medal to you. The report shows the reasons which led the Committee to its recommendation."