Ball Lightning

Abstract

PROF. J. C. JENSEN, of Nebraska Wesleyan University, Washington, describes in Physics, vol. 4, October, 1933, how he was fortunate enough to photo-graphball lightning when he was taking photographs of ordinary lightning in an August thunderstorm. The display of lightning was taking place in the region of the outrushing cold squall in advance of the main mass of the storm, and this squall was carrying with it great quantities of dust. In the wake of one of the flashes came the globular lightning, apparently floating slowly downwards. Two or three brilliant globular structures of the kind known as ball lightning appeared to travel along a pair of high-voltage power lines for a considerable distance, eventually falling to the ground and disappearing with a loud report. Two are clearly visible on one of the photographs, and, as their distance was known, it was an easy matter to determine their diameters, which were found to be very much larger than numerous observations of the phenomenon made elsewhere would have led one to expect, namely, 28 ft and 42 ft. Unfortunately, ball lightning is so rare compared with ordinary lightning that the much desired “confirmatory evidence of the occurrence of such large globular structures that might result from further photographs may be a long time in coming. There seerns no doubt from the repeated observations of ball lightning made inside houses, and from the size of holes made by it through window-panes, that it is generally much smaller.