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THE MOON’S CHANGES

(iv) the three-quarter moon in Taurus or Gemini, anda long time above the horizon. And, lastly, in mid-winter (i) the new moon is in Scorpio or Sagittarius,and only a short time above the horizon; (ii) the first-quarter moon in Pisces, and about twelve hours abovethe horizon; (iii) the full moon in Taurus or Gemini,and along time above the horizon; and (iv) the third-quarter moon in Virgo, and about twelve hours abovethe horizon.

The student will find no difficulty whatever inextending these considerations to other months, or inapplying much more exact considerations to specialcases. For he will notice that what has just beenstated presents only the rougher features of thematter. But nothing can be easier than to applythe first rough corrections for such an inquiry.Supposing, for example, that we wish to knowgenerally what will be the moon’s diurnal path(that is her course round the heavens during thetwenty-four hours) when she is at her first quarteron the 10th of April: we know that on the 10th ofApril the sun is some twenty degrees past the vernalequinox, which he had crossed on or about the 20th ofMarch; the moon at her first quarter is 90° fartherforward, or some twenty degrees past the place of thesummer solstice; corresponding to a position on theecliptic, about equidistant from the two stars k and8 Geminorum. Her course above the horizon willcorrespond to the sun’s course about twenty-onedays after the summer solstice,—that is, on or about