The Ben Franklins of Today 



They study lightning with the camera " 

 and at last they have told us what 

 it is and by what it is caused 



Lightning striking the 

 steeple of the First 

 Presbyterian church 

 of Greensboro, 

 North C arolina 



the most important part — the earth termi- 

 nal. The majority of the lightning con- 

 ductors in America are consequently un- 

 trustworthy. Unhappily these traveling 

 impostors are by no means extinct, al- 

 though increased knowledge is gradually 

 driving them out of the field." Besides, 

 the construction of the rod itself has 



THE recent progress of knowledge undergone improvement, 

 concerning lightning has far out- Scientific progress in the study of 



stripped the ordinary reference books, lightning is due, to a great extent, to 

 Thanks to Benjamin Franklin and his photography. Early investigators, such 

 famous kite, our great-grandfathers knew as Arago, Dove and especially O. N. 

 that lightning is an electrical discharge, Rood, had reached the conclusion that 

 and they were also familiar with the many lightning flashes are multiple, con- 

 lightning-rod. These gentlemen, however, sisting of several successive discharges 

 supposed that lightning commonly occurs along an identical path, and had also 

 in zigzags, with sharp angles, and not until formed a rough idea of the time intervals 

 photography was applied to the study of involved. Various forms of rotating disk 



the phenomenon 

 (about thirty-five 

 years ago) was 

 this erroneous no- 

 tion dissipated. 

 Our immediate 

 ancestors — in 

 this country, at 

 least — had like- 

 wise learned to 

 view the light- 

 ning-rod with 

 considerable sus- 

 picion. Early in 

 the nineteenth 

 century thou- 

 sands of defective 

 rods were erected 

 by ignorant or 

 unscru p ulous 

 itinerant "light- 

 ning-rod men," 

 whose names 

 have become a 

 by-word among 



The flash seen to the left of the steeple was virtually 

 instantaneous. That at the left of the chimney is 

 a multiple flash, lasting for a fraction of a second 



were used in their 

 experiments. Far 

 more accurate in- 

 formation on this 

 subject is now 

 obtained by the 

 use of a camera 

 mounted on a 

 vertical axis and 

 swung in a wide 

 arc, at a fixed 

 rate, by means of 

 clockwork. This 

 method has been 

 gradually evolv- 

 ed from the crude 

 process of merely 

 holding the cam- 

 era in one's hands 

 and giving it a 

 side-to-side mo- 1 

 tion — the method 

 followed by 

 Trouvelot since 

 the year 1888 



us. These persons, to quote a recent and by Weber and Hoffert in 1889. The 

 authority, "used all kinds of fantastic perfection of the moving camera is due, in 

 and peculiar shaped terminal rods and con- part, to Larsen, in America, but especially 

 ductors, the main object apparently being to Dr. B. Walter, of Hamburg, whose 

 to make as great a show with as little achievements in the photography of light- 

 material as possible. Their work is almost ning far surpass those of any other in- 

 entirely confined to the upper portion of vestigator. 

 the conductor, to the absolute neglect of Walter began by photographing, with 



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