Each varga cuts a sign into equal parts and gives the parts to signs counted on in order from a starting sign. Only the start changes from varga to varga: the sign itself, its 7th or 9th, or a set starting sign such as Mesha, Simha or Dhanu, chosen by whether the sign is odd or even, or movable, fixed or dual. The hora and the trimsamsa are the two exceptions.
☕ One pattern, sixteen settings
Parashara gives a construction for every varga (Brihat Parashara Hora Shastra (Santhanam–Kapoor ed.), ch. 6, vv. 5–41, pp. 68–86). Read side by side they share one pattern. Cut the sign into N equal parts. Find the starting sign. Give the first part to the starting sign, the second to the next sign, and so on round the zodiac.
The starting sign is where the vargas differ. Some start from the sign itself (the dvadasamsa). Some start from the sign in an odd sign and from another sign in an even one (the saptamsa, the dasamsa). Some look at whether the sign is movable, fixed or dual (the navamsa, the shodasamsa, the vimsamsa, the akshavedamsa). The bhamsa starts from the first sign of the sign's element.
Two vargas break the pattern. The hora gives only two signs, Simha for the Sun's half and Kataka for the Moon's. The trimsamsa's five parts are unequal and go to five planets' signs. The shashtiamsa keeps the pattern but finds the place by a sum: double the degrees in the sign and divide by twelve; the remainder + 1 is the place, counted from the sign itself.
Some of the book's printed grids could not be read in the scan we hold: the dasamsa, khavedamsa and akshavedamsa. What Nava follows: the rule the verse states. Every chart, these three included, is built from that rule, never from a copied grid.
The rule for each
- Rasi (D1), the whole sign, 30°: the sign itself.
- Hora (D2), 2 parts of 15°: in an odd sign the first half is Simha and the second Kataka; in an even sign the reverse.
- Drekkana (D3), 3 parts of 10°: the parts go to the sign itself, then to its 5th and 9th signs.
- Chaturthamsa (D4), 4 parts of 7°30′: the parts go to the sign itself, then to its 4th, 7th and 10th signs.
- Saptamsa (D7), 7 parts of 4°17′8.57″: count on from the sign itself in an odd sign, from its 7th in an even sign.
- Navamsa (D9), 9 parts of 3°20′: count on from the sign itself in a movable sign, from its 9th in a fixed sign, from its 5th in a dual sign.
- Dasamsa (D10), 10 parts of 3°: count on from the sign itself in an odd sign, from its 9th in an even sign.
- Dvadasamsa (D12), 12 parts of 2°30′: count on from the sign itself, in every sign.
- Shodasamsa (D16), 16 parts of 1°52′30″: count on from Mesha in a movable sign, from Simha in a fixed sign, from Dhanu in a dual sign.
- Vimsamsa (D20), 20 parts of 1°30′: count on from Mesha in a movable sign, from Dhanu in a fixed sign, from Simha in a dual sign.
- Siddhamsa (D24), 24 parts of 1°15′: count on from Simha in an odd sign, from Kataka in an even sign.
- Bhamsa (D27), 27 parts of 1°6′40″: count on from Mesha in a fire sign, Kataka in an earth sign, Tula in an air sign, Makara in a water sign.
- Trimsamsa (D30), five unequal parts (5°, 5°, 8°, 7°, 5°): odd sign: Mars 5°, Saturn 5°, Jupiter 8°, Mercury 7°, Venus 5°; even sign: Venus 5°, Mercury 7°, Jupiter 8°, Saturn 5°, Mars 5°.
- Khavedamsa (D40), 40 parts of 45′: count on from Mesha in an odd sign, from Tula in an even sign.
- Akshavedamsa (D45), 45 parts of 40′: count on from Mesha in a movable sign, from Simha in a fixed sign, from Dhanu in a dual sign.
- Shashtiamsa (D60), 60 parts of 30′: double the degrees inside the sign, drop the fraction and divide by 12; the remainder + 1 is the place, counted from the sign itself (a remainder of 0 is the sign itself).
- Mix-up: a varga is drawn from a printed table. The table is only the rule written out; the rule is what the book gives, and it is what Nava uses.
- Mix-up: the parts of the dasamsa in an even sign start from the 10th sign. They start from the 9th.
- Mix-up: the shashtiamsa counts from Mesha. It counts on from the planet's own sign.
Frequently asked questions
Why does the hora give only Simha and Kataka?
Because the hora is split between the Sun and the Moon, and each owns one sign. In an odd sign the first half is the Sun's, Simha; in an even sign the first half is the Moon's, Kataka.
Do the vargas have presiding deities?
Yes. The book names deities for the parts of most vargas. The deep dive below gives a few of them.
Does every software build the vargas the same way?
Not always. Some programs use other hora or drekkana systems from later books. Nava builds all sixteen from Parashara's rule as stated here.
Deep dive: the deities of the parts
Who presides over each part, and what this builds on.
🕉️ Presiding deities
The three drekkanas of a sign are presided over by Narada, Agastya and Durvasa (Brihat Parashara Hora Shastra (Santhanam–Kapoor ed.), ch. 6, vv. 7–8, pp. 68–70). The four chaturthamsas by Sanaka, Sananda, Kumara and Sanatana (Brihat Parashara Hora Shastra (Santhanam–Kapoor ed.), ch. 6, v. 9, p. 70). The dvadasamsas cycle through Ganesha, the Ashvini Kumaras, Yama and Sarpa, three times round (Brihat Parashara Hora Shastra (Santhanam–Kapoor ed.), ch. 6, v. 15, pp. 72–74). The shodasamsas cycle through Brahma, Vishnu, Shiva and the Sun (Brihat Parashara Hora Shastra (Santhanam–Kapoor ed.), ch. 6, v. 16, pp. 73–75). The bhamsa's twenty-seven parts take the deities of the twenty-seven stars.
🧭 What this builds on
The sixteen vargas and what each is read for are on the sixteen vargas. What happens when a planet keeps its sign across vargas is on vargottama and the varga grades.