Extracted text
Editorial transcription, lightly normalized from the scan. Line-break hyphenation, spacing, capitalization, and unmistakable OCR errors have been repaired; the claims remain those of The Flaming Sword.
Editor Flaming Sword:—I desire to ask a question for information: If the earth is concave, why does the sun appear to rise from beneath the horizon; and in setting, why does the earth appear to get between us and the sun and produce night? And why does not the sun shine over all parts of the earth at once? I would like for you to make this point as clear as you have made some others.—J. A. M., Gallion, Pa.
Why does the sun, if focused in our atmosphere, appear facing us when rising and setting? If it is true that the sun does not set behind the bulge of the earth, why cannot one see it with a telescope after it sets, the same as the ship after it has gone beyond the horizon?—M. D. W., Fenton, Mich.
The apparent rising and setting of the sun are the result of optical illusion produced by perspective and curvation of light. When the sun is rising, it is actually coming down toward our meridian; and actually going up when setting. The curved rays of sunlight sweep down and out through space, and enter the eye in a horizontal direction, when the sun is 90° east or west of us. The general arrangement of the visible heavenly bodies is that of a sphere, which is convex to us. We can see no more than a hemisphere of the heavens, for the simple reason that there can be no more than 180 degrees from horizon to horizon. No one can see more than one half of the surface of a sphere at any given moment. The relief of the sphere of the heavens is reversed through the factors of visual impression and curvation of light.
The horizon is the apparent meeting-point between the sky and earth; hence the apparent interposition of the earth between us and the sun. As a crude illustration of how the sun appears to rise and set, we refer to an electric light on a tower in the distance; it appears near the horizon; but it appears to rise as we approach the tower until, when directly beneath the light, it appears to be in the zenith. The sun is an electric light on a large scale; as it comes toward us over the great concavity, it appears to rise; as the sun recedes to the west, it appears to go down until it apparently drops below the horizon.
We appear to see every part of the sphere of the heavens at right angles to the surface of the sphere, because the factors mentioned above reverse the relief of the sphere. The sun, therefore, appears to face us, no matter what its position is in the heavens. The reason the telescope does not restore the sun to view after setting, is because no telescope is powerful enough to overcome the effect of foreshortening of the earth's surface; it cannot project the horizon far enough beyond the limit of lateral vision of the unaided eye. The horizon appears against the sun's disc when the sun is setting; we can see no more of the sun with the telescope than with the naked eye, because the case is not altogether analogous to that of the disappearance of the ship's hull, which sails on the surface and may be restored to view, provided the ship is not beyond the telescopic horizon. The sun at setting is about 6,000 miles away; the ship, only a few miles.
The source scans remain the record. This page preserves the article's argument without presenting its conclusions as independently established results.
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The source scans remain the record. This page preserves the periodical's argument and reported observations without presenting its conclusions as independently established results. The claims remain attributed to The Flaming Sword.
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The Flaming Sword · Vol. 16, No. 28 · 30 May 1902 · PDF pp. 13-14