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Show HEIGHT OF ATMOSPHERE. One Hundred and Thirty-One Miles, Says Scientist, and He Has Measured It. Ono hundred and thlrty-ono miles is tho height of the atmosphere, ns measured by Prof. T. J. J. Seo, who determines tho thickness of tho nlr envolopo by noting the dlfferenco bo-tweon bo-tweon tho tlmo of sunset nnd tho com-plcto com-plcto dlsappeainncu of bltiu from the Tho moment nt which tho blue changes Into black can bo observed qulto easily with npproxlmato certainty cer-tainty by tho naked cyo when tho nlr Is clear, nnd by trigonometry may bo ascertained tho dlBtanco below tho horizon of tho sun nt tho moment of change. By this means may bo calculated cal-culated the height of tho smallest Illuminated Il-luminated particles of oxygen and nitrogen, ni-trogen, which glvo to tho sky Its bluest tint by tho reflection ot tho smaller wave lengths of tho sun's light. Tho instant tho chansjo from blue to black Is possibly .1 Uttlo dltllciilt of exact observation, tint tho "method Is not more doubtful than that based on tho observation of Bhootlng Blurs. The shooting star method gives a result re-sult not greatly differing from the vunlshlng hluo method. Tho former gives tho height of tho atmosphere at 109 miles. |