What a named division adds
A divisional chart answers which sign. A named division answers which slice of that sign, and the texts attach a character to the slice directly — independently of the sign, its lord, and everything else in the chart.
This matters most in the D-60. Parāśara gives the ṣaṣṭyāṁśa decisive weight in judging the fine condition of a graha, and the names are the mechanism: sixty slices, each labelled, roughly half of them benefic and half malefic. Two charts a minute apart can put the same planet in Amṛta and in Kāla.
It follows that these names are only as good as the birth time. At thirty minutes of arc, a ṣaṣṭyāṁśa changes about every two minutes of clock time. If the birth time is approximate, read the sign and ignore the name — a precise-looking label on an imprecise time is worse than no label at all.
The sixteen named tables
Each is computed from the graha's exact longitude. The source column is the verse the table comes from, and it is carried through to the result.
| Division | Named parts | Arc of one part | What the names are |
|---|---|---|---|
| D-2 Horā | 2 | 15° | Surya and Chandra horā — the solar and lunar halves |
| D-3 Drekkāṇa | 3 | 10° | Nārada, Agastya, Durvāsa — the three sages |
| D-4 Chaturthāṁśa | 4 | 7°30′ | The four regents of the quarters |
| D-7 Saptāṁśa | 7 | 4°17′ | The seven named parts, running in opposite order in even signs |
| D-9 Navāṁśa | 9 | 3°20′ | Deva, Nara, Rākṣasa — repeating three times |
| D-10 Daśāṁśa | 10 | 3° | The ten dikpālas, the guardians of the directions |
| D-12 Dvādaśāṁśa | 12 | 2°30′ | Gaṇeśa, Aśvinī, Yama, Sarpa — repeating |
| D-16 Ṣoḍaśāṁśa | 16 | 1°52′30″ | The four-fold cycle of Brahmā, Viṣṇu, Śiva and the Sun |
| D-20 Viṁśāṁśa | 20 | 1°30′ | The twenty forms of the Goddess |
| D-24 Siddhāṁśa | 24 | 1°15′ | The twenty-four named parts of learning |
| D-27 Bhāṁśa | 27 | 1°06′40″ | The twenty-seven nakṣatra names |
| D-30 Triṁśāṁśa | 30 | unequal bands | The five unequal bands and their presiding deities |
| D-40 Khavedāṁśa | 40 | 45′ | The forty named parts |
| D-45 Akṣavedāṁśa | 45 | 40′ | The forty-five named parts |
| D-60 Ṣaṣṭyāṁśa | 60 | 30′ | The sixty names, each classed benefic or malefic |
| D-150 Nāḍyāṁśa | 150 | 12′ | The 150 nāḍī names, with their movable, fixed or dual character |
The D-150 is not from BPHS chapter 6 — it comes from the Nāḍī literature (Deva Keralam / Candra Kalā Nāḍī), and the engine labels it with that source rather than implying Parāśara. Its parts are unequal, following the Ṣoḍaśavarga cusps.
The ṣaṣṭyāṁśa, and why it is read first
Of the sixteen, the D-60 is the one to look at. Parāśara gives it the highest weight in the Vimśopaka schemes, and the reason is the arithmetic: at half a degree a division, it is the finest statement the chart makes, so it is the one that distinguishes two people born minutes apart.
The names are read as a condition on the graha rather than as a prediction. A benefic ṣaṣṭyāṁśa supports whatever the graha was already going to do; a malefic one undermines it. It does not reverse a strong placement, and it does not rescue a ruined one.
One caution worth stating because it is commonly ignored: a malefic ṣaṣṭyāṁśa name on a benefic graha is not a reason to re-read the whole chart. It is one layer among many, and the sixteen tables were never meant to be read as sixteen verdicts.