The Universal System of Astronomy, Part Two

From the possibility of [observation], both [values] are reached in this way; this is desired... 21 ...having gone through the three-fold path, the desired result is stated.

From the true declination sphuṭa-apakrama; the angular distance of a celestial body north or south of the celestial equator, corrected for specific orbital variations and other factors, the calculation is to be accomplished through the refined measurement. Thus, speak of the refined position original: saṃskṛtam; refers to a mathematically "corrected" or "purified" value of the planet.

22 The days and the time passed therein, and how much of the night has passed, that is the temporal state. From that time, again, the same [process is followed]... from the hypotenuse karṇa; the diagonal line of sight or the calculated result of the shadow's triangle, the zenith distance nata-bhāga; the angular distance of the planet from the point directly overhead is determined.

In this manner, by the method of the Sun, the planets are known. The true position sphuṭa is refined. When the planet is at the [sighting] hypotenuse, its own path is established. The true declination original: spaṣṭa-krānti should be calculated, as well as the mean declination original: madhya-sādhā from these values.

Here, following the direction of its own declination... the planetary motion is seen when the true declination is calculated. From the hypotenuse obtained through this observation, the hour angle of the planet nata-kāla; the time elapsed since the planet crossed the local meridian is found.

By subtracting this from midday dinārddha; literally "half-day", the [current] time is found. In the eastern hemisphere pūrva-kapāla; the half of the sky where celestial bodies rise, the hour angle represents the time before noon; in the western result apara-phala, the hour angle indicates the time past noon.

Then, through the sighting correction dṛk-saṃskṛti; a correction applied to account for the observer's specific visual perspective, as performed previously, the true ascendant lagna; the sign of the zodiac rising on the eastern horizon and the temporal calculations are established.