Extracted text
Editorial transcription lightly normalized from the cited scan; historical claims below are those of The Flaming Sword and are not independently verified.
Extend a rail horizontally and in a perfectly straight line. We do not mean by this on a line level with the surface of the earth; we mean an air line. Place over this rail, and parallel with it, a tube twelve or fourteen inches long, horizontally across the objective end and middle diameter of which is a hair line, and through the visual or subjective end a needlehole. Place this instrument about ten or twelve inches (it may be more or less) from the rail. Now, look through the middle or longitudinal axis so that your line of vision is from the needle hole across the hair line at the objective end.
This line of vision—though exactly parallel with the rail—will seem to strike the rail on a level with your line of vision through the instrument, at a distance from the instrument determined by the distance of the instrument from the rail. The hair line of the instrument (if the rail is an air line) will appear to cross or strike the rail exactly at the horizon of the rail. Place another rail curved eight inches upward, relating the instrument in the same way, and the hair line will seem to strike the sky a trifle above the horizon of the concave rail.
Extend a convex rail curving downward instead of upward, placing the instrument correspondingly above the rail, and the hair line will cross the rail a little below the horizon. By this experiment we obtain three distinct visual phenomena.
If we place the same instrument over a level canal or smooth body of water long enough to make a corresponding observation and experiment, we find that the experiment reveals the same phenomenon as the concave rail curving upward eight inches to the mile, but unlike the other two experiments. This is proof positive that the earth is neither convex nor flat, but that it is concave.
Any civil engineer may demonstrate the concave theory by a simple experiment, even more simple than the one above presented. Start a line leveled with the spirit level or the theodolite, then continue the line, not leveled with the earth but on an air line. It will be found in every instance to run into the ground. Or perform the experiment over an extended water surface: the line—we do not mean the apparent visual direction—started on a level and continued on an air line, will invariably strike the water.
Elevate a post ten feet in altitude. Place a spirit level so as to start an air line in either direction from the top of this post: it will be found that the two lines are at exactly right angles with the post. Now, if we extend these directions—not with the spirit level, but with the instrument described above, placed by the side of the level cord—an air line will direct the two air line cords from the post into the ground at the distance of about, or a little more than, three miles and a half. The cords would be extended to meet the earth or water surface at those points. We have then the cord, the arc, and the radius vector of ten feet. This will show a concavity of ten feet in a distance of about seven miles. This argument is unanswerable. The earth surface is concave, as actually demonstrated by physical test. Its diameter is about eight thousand miles, as already fully demonstrated and declared through the literature of the Guiding Star Publishing House.
We have taught this theory of the contour of the earth since 1870.
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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. 9, No. 5 · · PDF p. 1