ogy is in some respects more complex than either Nativities or Horary Astrology.
The nature of the influence of the heavens upon human destiny has been differently represented by different astrologers, some claiming that the heavens merely exhibit signs of events, so that when these are properly interpreted the future can be foretold, and others holding that they are causes of the events. Most, however, seem to believe that they are both.
Astrological calculations are made by means of the sun, moon, and planets, the signs of the Zodiac, and the various aspects and relations of the planets. To work the problems, a "figure of the heavens" is drawn. This is merely a map to represent the heavens at any particular moment, such as when a child is born, a question asked, etc. It is made by drawing three circles and then drawing lines to represent the horizon, and others at right angles with them to represent the meridian. Thus will be shown the
![](http://upload.wikimedia.org/wikipedia/commons/thumb/1/16/Illustration_Page_71.png/250px-Illustration_Page_71.png)
natural divisions formed by the rising and setting of the sun, and by his passing the meridian at noon and midnight. Each of these quarters or quadrants is to be divided again into three equal parts, forming the twelve houses. The accompanying figure, from Lilly's "Introduction to Astrology," exhibits the method.
In calculating a nativity, the horoscope must be cast for the instant the child is born, and the figure show exactly the state of the heavens at that instant as