In this sacred tradition, one begins by marking a circle with precise units measured by the desired finger lengths, ensuring the form is even and true. The points where the tip of a shadow touches the circle—once in the forenoon, once in the afternoon—are carefully noted, for these mark significant moments. In the very center of the circle, a straight line is drawn with a thread, stretching from south to north, establishing the primary axis. To determine the intermediate directions, one looks to the symbolic fish set at the heart of these directions, and in the same way, the sub-directions are discerned. With the arm-string and the prescribed finger units, the radiance or brilliance at that spot is measured. Thus, the circle traced by the shadow and the path of the equinox are described together. Between the shadow at the chosen moment and the equinoctial circle, the tip or point of intersection is named and observed. When the base is set up in the form of a gnomon—a simple vertical stick—the shadow’s movement is measured in reverse, tracing its arc backward. Through correct methods, with devotion and attention to the shadow’s qualities, the results are obtained according to the number of days that have passed. From this contact between light and shadow, the brightness, the darkness, and even the opening of petals and similar phenomena are produced. The vertical and horizontal chords formed by these shadows are always taken as the southern vertical and horizontal chords. The other segments of the sun’s path are understood as the chords of its rays, or as segments at the tip of the shadow. By dividing with the chord at the tip, one calculates the shadow upon the outer edge of the circle. What remains marks the beginning of dividing the directions, and its chord is multiplied by a threefold chord for further calculation. At the start of the sign Cancer, one subtracts from half the circle; at the start of Libra, one adds to half the circle. By repeatedly applying the sun’s slow and fast motions, the mean position of the sun is determined. The sum of the circle’s motion and the values obtained from these calculations is known as the daily and nightly motion. The chords are then divided in order by one, two, and three, each representing a separate bow or arc. For their respective eight divisions, the sun, moon, and other planets are assigned: one for autumn, three for winter, and so forth. These, both individually and together, are combined with the signs beginning with Cancer and onward. The portions to be experienced—those to be enjoyed—are calculated, especially for the evening, using the sun’s desired positions. From the desired daṇḍikā and the subhā, one must subtract the portions already enjoyed. The remainder, increased by thirty in order, is then divided by the incorrect value to adjust the calculation. The same method applies to the eastern and western nadīs, and to the portions at sunrise and sunset. If the portion to be enjoyed is less, or the portion already enjoyed is greater, then adjustments are made accordingly. Should the portion of the sun’s rays be less than that of Indra, the eclipse is attributed to the moon. Just as a covering can obscure the sun, the moon, or the earth, so too does an eclipse conceal these celestial bodies. Both what is covered and its covering are measured—sometimes as half, sometimes as one-sixth, or even ten times the portion. Half the duration of stability is determined by measuring the portions of the limbs and arms. If there is an excess, then in such clear and pleasant endings, different measures apply. Here, the full ending is taken as the middle; at the end of the new moon, it is three times the portion. That portion is multiplied by its direction, two is subtracted, half the sun’s value is added, and thus the result, called Hari, is obtained. The support of Hari is gold; with three times the portion, one is added to the measure. The support of the arrow is six times less; again, one is added, then three times the portion. With six, marked by sound and the moon, the bowing, non-bowing, and the portion of direction are measured with devotion. In the covered state, the leaf is established by taking half the duration and three times the portion. From the calculation of these two, half the duration becomes clear. The world and the lord are considered less than the sun, with portions of nine and fifteen, respectively. First, one observes the planet’s disc and its support with the eyes. When the planet sets, it is known to be a composite phenomenon; the wise, through careful observation, determine the precise times of its arrival and departure.