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Show LIGHTNING FLASH COULD LIGHT ! YOUR FIVE-ROOM FLAT FOR MONTH r Ti unf1n;;tnr:efla?h of ""tnmg wouiS ure?Vn?P5y r " ,,trhlni"K riasni fig-'wooi fig-'wooi . a , ' "n5i ,,,r kilowatl hour, , would be worth 7.) cents, savs Dr 23S25 p;.8l1,lm,eti who h . f,th'' Pn,-r"' Blectrl Co 'Xbject ' completed .1 study of the 'to k5 SSJ'VlPl! St''"ielz computes iW b. j-bout IR.000 000 foot pounds, or strikes with th energy of a Mn-.,, train golnc at 50 miles an hour I - , P "BRINGS HA l N ughtning is the passage of a very ngh voltaKe current of , , , , , -rom one spot to another " Dr Btelnmets. But, while it is true ih n Kaslonally this .iirrent prases from loud to rlourf or from - loud to earth, it usually IS within a thundercloud It, therefore, seems to be due to qualizatlon of electric pressure differences dif-ferences within the cloud, rather than to this charge between opnositel) ebarjferl bodies. Lightning occurs mainly w hen rap-Id rap-Id condensation of moisture u 1 Place In the air. and the electric phenomena phe-nomena seem to ho the more intense tin- greater the rapidity of condensation conden-sation or rain form;itr,;, Thus the atmospheric electric disturbances dis-turbances seem to be connected with the louds and rain. And there voti have the reason why lightning i usually us-ually coincident with a rainstorm THE RAINDROP. ' A raindrop, of course. Is made tip of tiny particles of moisture- Man J such particles unite and so form larger larg-er particles. These In turn unlie and ultimately a raindrop of l-intti to 2-l(lths of an Inch ln diameter Is formed, Hut remember that each of these tiny particles of moisture contained a small charge of electricity .and as the particles unite to form the raindrop ill theve electrical charges unite, "The electric charge is contain' " on the surface of the raindrop While the surface r the la re, raindrop is larger than that of each of the thou--andl of itny drops which have come together to compose It. 11 lg Very much smaller than the sum of their surfaces, sur-faces, and the Charges of all these Uropleln thus arc collected and com-, com-, pressed on the surface of the one big drop- that is th.. charge on the big drop is under much higher ilectne pressure Kut tVn- is a limit to the electric pressure which the at, can stand j "You have noticed that rain clouds lare dark, sometimes black, shading ofl (to lighter portions. The dark sections jappear darker than the rest because they contain more moisture, "Hence they contain a greater amount of electricity than the lighter light-er portions, are under higher electric pressure or voltage, and there is an unstable equilibrium, until rinallj th accumulation of elOCtricit) at one such point becomes sufficient to overcome ov-ercome the resistance of the Inter- j jvenlng air. and there Is a lightning' flash and the voltage is equalised. There are really three things which ! make up the lightning flash: 1 "The electric pressure, or 'voltage' Of the thundercloud "The current or flow of electricity' in the discharge, given In 'ampieres.' I "The duration of the discharge. "All Hies.- three quantities multi- plied give the energy. "The human eye. of course, is not eapable of measuring the Inflnltestm-nll- short duration of a lightning flash, and the f'nsb is n merely because the eye retains an image It receives for a fraction of a second alout one-tenth one-tenth of a second." in Stdnmcta IVorli n Studs "f Llglitnlng. |