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William Jennings, Pioneer Work in Photography of Lightning, 1930

Lightning Striking

Jennings named the types of lightning he photographed according to their patterns of electric discharge. The table below outlines the forms reported on by The Franklin Institute, paring each with a digitized version of the original image.

"Branched" discharge: named for the delicate "branches" created by its electric discharge. Report Plate 3
Report Plate 3. (147K)

"Beaded" lightning: a photograph of this unique form of lightning was printed in the French publication "La Nature" (Nature) and entitled "the rosary." Report Plate 4
Report Plate 4. (115K)

"Ribbon" lightning: in an article printed in the Journal of The Franklin Institute, Jennings explained that wind moving across the path of lightning in space produced a ribbon-like form of lightning. Report Plate 5
Report Plate 5. (165K)

"Multiple flash": Jennings showed that lightning sometimes prepares a path for successive flashes. Report Plate 7
Report Plate 7. (128K)

"Meandering" flash: form of lightning discharge that takes place from cloud to cloud, usually occurring at the end of a storm. Report Plate 9
Report Plate 9. (120K)

Subject to debate: this photo captures the phenomenon of a brilliant main flash with dark side branches, the cause of which has been given a great deal of discussion. Report Plate 10
Report Plate 10. (231K)