| 摘要 |
A meridian indicator comprising a base plate, an inclined plate disposed at a selected angle to the base plate, an hourly graduated arcuate plate, means rotatively supporting the arcuate plate upon the inclined plate, a rectangular style plate, means supporting a first edge of the style plate at a selected angle to the inclined plate, means angularly displacing the style plate at a selected angle relative to a horizontal plane, a weighted string means attached to a second edge of the style plate which is parallel to the first edge, aperatures in the inclined plate and the arcuate plate positioned so that weighted string means adjustably passes therethrough, and a latitude scale means deposed on the inclined plate and juxtapositioned to the weighted string means as it passes through the aperatures, an equation of time correction scale means disposed upon the arcuate plate, and a longitude scale means disposed upon the inclined plate in juxtaposition to the equation of time correction scale means, the arcuate plate having hourly graduations so that when a third edge of the style plate is pointing to true north, the shadow of the sun of the third edge of the style plate falls correctly upon an hourly graduation upon the arcuate plate to read true solar time.
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