Charts of divisions bring an additional dimension to astrology. Unknown in the West, they respond to practical questions: how to read what happens to a child, partner, occupation, etc.? They have the disadvantage (or perhaps an advantage for those who dare to take the step) to require the use of the sidereal zodiac. Their use is simple. In India, there is not an astrologer who is serious who does not make a chart of the Navamsa or D9, together with the natal chart. Each area of life (children, parents, marriage, problems, etc.) has its own chart of division (CD) assigned. It is often of little use to establish a list of aspects of the chart of division studied or to interpret a chart of division in the same way as a birth chart. It's easier.
It is as if we extracted a special zodiac from the natal zodiac and that this corresponds to a particular area of life. Suppose we have a planet located at 10° 11' 34'' of the constellation of Aries and that we want to find its position in the D9 (partners). Divide 30° (a constellation) by 9. This gives 3° 20'. From 0° Aries to 3° 20', one remains in Aries. From 3° 20' to 6° 40' Aries, any planet will be located in the Taurus. From 6° 40' to 10° 00', it will be in Gemini. From 10° 00 to 13° 20', it will be in Cancer. And so on ...
In practice it is less clear, because some divisions are not linear and that means it is not possible to simply divide (or rather multiply) to find the position of a planet. The Anglo-Saxons use a similar system they call harmonics.
Here is a list of the main divisions:
D2 Riches (general) Hora
D3 Brothers and sisters Drekkana
D4 Money, assets Turyamsa
D5 Way of thinking Panchamsa
D6 Health Shashthamsa
D7 Children Sapthamsa
D8 Radical changes
D9 Partners, sexual behaviour, Navamsa
D10 Profession Dasamsa
D11 Longevity Ekadasamsa
D12 Parents Dwadasamsa
D16 Home, luxury Shodasamsa
D20 Spirituality Vimsamsa
D24 Instruction, apprenticeship, courses, studies Chaturvimsamsa
D27 Strengths and weaknesses
D30 Problems Trimsamsa
D40 Maternal karma
D45 Paternal karma
D60 Karma - previous lives
In order to use the DC:
If the natal chart (D1) expresses the being, the body, other DC's can almost be read as individual charts, depending on the area involved. However, it is unnecessary to explore these charts too deeply. One must extract the essentials: rulers, planets in problematic houses (that is to say the Houses 6, 8 and 12) or not, and the most obvious aspects (conjunctions and oppositions). Never interpret a ruling planet of the House 6 of D6 in House 2, for example. This is unnecessary. Stick to the basics! Also the planets never intervene all at once, but according to different chronologies, measurable in time. The planets in conjunction in a DC indicate the importance of an aspect of the chart concerned.
By far, the periods of the Nodes or the "black" planet (the most problematic, the most
malefic, it is often the ruler of the House 8 or the South Node) indicated by the planetary forces, pose the most problems. If the planetary period touches on a planet in fall in a chart of division, it will cause problems in the division concerned. The reverse is true in case of exaltation or domicile.
We all have our share of problems. One should not become pessimistic
in interpreting the periods and the tones, but to see what should be done
to improve things and to get stronger. In other words, meet the challenge
by exercising caution and wisdom!