Period-determination: each specialised lagna is a fixed-stride walk through residues of R derived from the Janma-lagna start — period is forced by the stride's order in (ℤ/12ℤ)*.
विशिष्ट-लग्नानि
Viśiṣṭa-Lagnāni
Specialized Lagnas · 5 ancillary ascending points
Advances at 1 sign per ghaṭikā-pair from sunrise. Maps the "lived-day" tempo — each 48-min slice corresponds to one bhāva of the natal-day ascendant cycle.
Twice the speed of Bhāva-Lagna — 1 sign per 24 min. Used in financial-event timing where the day-cycle resolves to the hour-cycle. Phaladīpikā recommends horā-lagna for muhūrta-selection in commerce.
Fastest specialised lagna — 1 sign per 12 minutes. Sensitive to precise birth-time correction (rectification). The ghaṭika-lagna lord's bhāva placement in the natal grid is read for power and recognition.
The Moon's prosperity-lagna. Computed via kalā-sum of Moon-nakṣatra-lord and 9th-bhāva-nakṣatra-lord, counted forward from Moon's rāśi.
The Lakṣmī ascendant — read for marital harmony, abundance, and fortune. Computed as Moon's-longitude − Lagna's-longitude, then located on the sidereal wheel from the lagna.
For event-timing within a day: read the day's transiting grahas against the Bhāva / Horā / Ghaṭika-lagna progressions. A muhūrta where all three align with a benefic is exceptional.
Read 2nd-from-Indu-Lagna (wealth) and 11th-from-Indu-Lagna (gains). If both house-rulers sit in their own / exalted signs in the natal D1, the chart carries durable prosperity-yoga (BPHS 5.40 dhana-yoga-pattern).
7th-from-Śrī-Lagna (spouse) cross-read with D9 navāṃśa: if both indicate the same dignity-class, the marital chapter unfolds smoothly. Discord between the two signals an opportunity for ritual harmonisation.
The Birth-Chart caster computes Janma-Lagna and Moon's exact sidereal longitude — sufficient to derive Indu-Lagna, Śrī-Lagna, and the rapid progression lagnas.
KAAL Truth #5: The five lagnas provide additional reading-frames. Their qualitative integration — and any predictive synthesis — belongs to the learned Jyotiṣī.