OCR Text |
Show LIGHTNING FLASHES, Lightning flashes in a storm ore found by an English observer to bo much less irregular in period than they appear. Such storms havo usually two foci sometimes three from which the flashes radiate, and the discharges from ench come at regular intervals. Tlio apparent irregularity is duo to tho varying rates of tho different tenters. In a storm of July, lQOri, tho two foci wero about a mile ond a half opart, and in an hour the northern center emitted 30 flashes at intervals of 15, 30, -15, CO and U0 seconds, nnd tho southern center gave 1C flashc3 at intervals of 17, 31 and 51 seconds. sec-onds. Another unexplained observation obser-vation is that just beforo each great flash there is n momentary faint lighting up of tho sky in tho storm region. |