 | Chemical Society (Great Britain) - 1900 - 1466 pàgines
...the same chemical action as the sun would do if shining from a cloudless sky at the height of 9°53' above the horizon. On comparing the visible brightness...sun's disc, as measured by the eye, is 524-7 times aa great as that of burning magnesium when the sun's zenith-distance is 67°22', whilst at the same... | |
 | 1864 - 654 pàgines
...shining from a cloudless sky at a height of 9° 53' above the horizon. On comparing the chemical with the visible brightness of these two sources of light...brightness of the sun's disc as measured by the eye when the sun's zenith distance was 67° 22', is 524- 7 times as great as that of the burning magnesium... | |
 | 1864 - 648 pàgines
...shining from a cloudless sky at a height of 9° 53' above the horizon. On comparing the chemical with the visible brightness of these two sources of light...brightness of the sun's disc as measured by the eye when the sun's zenith distance was 67° 22', is 524-7 times as great as that of the burning magnesium... | |
 | Literary and Philosophical Society of Manchester - 1864 - 1170 pàgines
...horizon. On comparing the chemical with PROCEEDINGS— LIT. & Tail.. SOCIETT— No. 12.— SESSION 1863-64 the visible brightness of these two sources of light...brightness of the sun's disc as measured by the eye when the sun's zenith distance was 67° 22', is 524-7 times as great as that of the burning magnosium... | |
 | Royal Institution of Great Britain - 1866 - 730 pàgines
...if shining from a cloudless sky at a height of 9° 53' above the horizon. On comparing the risible brightness of these two sources of light, it was found...burning magnesium wire when the sun's zenith distance is i>7 22' ; whilst at the same zenith distance the sun's chemical brightness is only 36*6 times as great.... | |
 | HUGH W. DIAMOND, M.D., F.S.A. - 1866 - 516 pàgines
...at a height of 9° 53' above the horizon. On comparing the chemical with the visible bright- ! ness of these two sources of light, it was found that the...brightness of the sun's disc, as measured by the eye, when the sun's zenith-dis- j tance was 67° 22', is 524-7 times as great as that of tho burning magnesium... | |
 | Andrew Ure - 1867 - 1144 pàgines
...shining from a cloudless sky at a height of 9° 58' above the horizon. On comparing the chemical with the visible brightness of these two sources of light,...brightness of the sun's disc, as measured by the eye when the sun's zenith distance was 67° 22', is 524'7 times as great as that of the burning magnesium... | |
 | sir Henry Enfield Roscoe - 1869 - 396 pàgines
...sun; and they suggested the application of this light for the purpose of photography. They showed1 that a burning surface of magnesium wire, which, seen...magnesium wire, when the sun's zenith distance is 67° 22' ; whilst at the same zenith distance the sun's chemical brightness is only 36'6 times as great.... | |
 | Henry Enfield Roscoe - 1870 - 514 pàgines
...sun ; and they suggested the application of this light for the purpose of photography. They showed 1 that a burning surface of magnesium wire, which, seen...magnesium wire, when the sun's zenith distance is 67° 22'; whilst at the same zenith distance the sun's chemical brightness is only 36 6 times as great.... | |
 | sir Henry Enfield Roscoe - 1870 - 452 pàgines
...point the same chemical action as the sun would do if shining from a cloudless sky at a height of & 53' above the horizon. On comparing the visible brightness...magnesium wire, when the sun's zenith distance is 67° 22'; whilst at the same zenith distance the sun's chemical brightness is only 36'6 times as great.... | |
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They showed* that a burning surface of magnesium wire, which, seen from a point at the sea's level, has an apparent magnitude equal to that of the sun, effects on that point the same chemical action as the sun would do if shining from a cloudless sky... 
