The Velocity And Duration Of Lightning

A large flash of lightning, dtélinctly neon, oíton leaves upon the niiiid mi impresaion that it luis astcd fully a seoond or more,but it is proved fcbat snch is nót Uio l'act. Its velocity ia at the rute of 288,000 miles por eooond. The utmost (luralion di d ilash frota bezinning d end is estimated aot lo e d II"' :si,tli .-ul pfasecqnd, thotigh retained apon the Tetina so muöh longer. Thi:; 1 1 1 : v be proved duni'g i slorm un ii perfcctly dtitk níght by setting a wheel to work so rapidly thiit in íi steadyUght ita spokos appcar to blond and become individually invisible. It being dark, and thc waeel rapidly rovolving a above, when á flash of ligntning oocors the wheel wiil íijipcar to khe eye motiónless, cvcrv spolld being (lislinclly md sepa lülciy visible . md still. ThlS v:is lirsl obsei-vod by Whcfttafcooe, and ia iteeoïded liv hini, jn conjunotion with othci simi lar oxperiménta, as oonclusive prooi that the dui-ation oí the (lash is seessiToly brief. '__ Hbre is an extract from a letter witten to lier lover by a Montgomery, Alabama, girl : " For your sáike, daríing, T Itóve quil using ohewing-gum ; worild yon ijuit j;um fov uKí '; I wouldnot have quit gum for auy other peruon in the whole wovldl"