《Tetrabiblos》The Periodical Divisions Of TimeClaudius Ptolemy（Ashmand 英譯 1822）
It follows, accordingly, that the time contained in the space between rising or setting, and either meridian, must be equal to the time between the _same_ meridian and rising and setting; because the meridian divides equally such portions of the parallels as are above or under the earth.
段落 tetra-4-theperiodi-65public-domain (Ashmand 1822)
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