《Tetrabiblos》The Zodiacal PlanisphereClaudius Ptolemy（Ashmand 英譯 1822）
Ptolemy’s “Exemplification” has been followed thus minutely in order to show how perfectly Mr. Ranger’s invention is adapted to assist (if not to supersede) arithmetical calculation; for, after the Planisphere has once been accurately laid down, a line drawn parallel to the equator, from the significator to the promittor, or to the promittor’s pole of position, and measured by degrees of the equator, will accomplish the whole operation of ascertaining the amount of prorogation.
段落 tetra-4-thezodiaca-17public-domain (Ashmand 1822)
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