They showed 1 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... Spectrum analysis, 6 lects - Page 40by sir Henry Enfield Roscoe - 1870Full view - About this book
| Chemical Society (Great Britain) - 1900 - 1466 pages
...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 - 332 pages
...shining from a cloudless sky at a height of 9° 53' above the horizon. On comparing the chemical with ike visible brightness of these two sources of light it...brightness of the sun's disc as measured by the eye when the sun's zenith distance was 67° 11', it 514-7 times as great as that of the burning magnesium... | |
| Great Britain. Patent Office - 1861 - 766 pages
...sunlight. The chemical brightness of the sun, in the latitude of Heidelberg, was ascertained to be 36'6 times as great as that of burning magnesium wire when the sun's zenith distance is 67° 22'. By means of a quartz prism and other appliances the chemical action of the various parts of the solar... | |
| Literary and Philosophical Society of Manchester - 1864 - 1170 pages
...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... | |
| 1864 - 648 pages
...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 - 654 pages
...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... | |
| Royal Institution of Great Britain - 1866 - 730 pages
...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 pages
...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 pages
...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... | |
| Henry Enfield Roscoe - 1870 - 514 pages
...point the same chemical action as the sun would do if shining from a cloudless sky at a height of 9° 53' above the horizon. On comparing the visible brightness...zenith distance the sun's chemical brightness is only 36 6 times as great. Hence the value of this light as a source of the chemically active rays for photographic... | |
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