पञ्चसिद्धान्तिका (आचार्य वराहमिहिर - सूर्य, रोमक, पौलिश, वासिष्ठ एवं पितामह सिद्धान्त)

50 PAÑCASIDDHĀNTIKĀ III.11 [अहर्मानम्] मेषादि(षु तदु)पचि(तैः) कर्कट[का]द्येषु तदपचयमितैः । दिनवृद्धिरसाध्ये(त) क्षयस्तुलाद्येषु [कर्कटकात्] ॥ ११ ॥ सागरहिमगिरिपरिधौ स्पष्टमिदं चरविनाडिकाकर्म । अन्यत्राऽपि यथैतत् स्पष्टं तच्छेद्वके वक्ष्ये ॥ १२ ॥ Day-time 11-12. To find the day-time in Meṣa, Vṛṣabha and Mithuna, add the cara differences one by one, in the order given, to 30 nāḍikās, and in the next three, subtract in the reverse order. In the next three rāśis, Tulā, etc. subtract from 30 nāḍīs in the given order, and for Makara etc. add in the reverse order. This will give the day-time fairly accurately for places in Northern (whole?) India. I shall give the method to find the day-time accurately in other places (in the IV chapter) when dealing with spherical astronomy. Thus, when the Sun is in the six rāśis, Meṣa, etc. 30 nāḍikās cara-vināḍīs = day-time. When in the six rāśis, Tulā etc. 30 nāḍikās cara-vināḍīs = day-time. The increase over 30 nāḍikās and the decrease to 30 is by Eq. shadow × {20, 16½, 6¾, 6¾, 16½, 20}vināḍīs. This is repeated in the decrease from 30 nāḍīs and the increase to 30, in the six rāśis from Tulā. We shall explain all this in the IV chapter. The cara-vināḍīs computed in the above manner and the day-time got by them will be accurate only in Northern (whole?) India it has been said. The reason for this is as follows: From the expla- nation of the method of computing the cara-vināḍīs, it can be noted that sine cara is proportionate to the Eq. shadow, and the cara-vināḍīs are proportionate to the arc obtained from sine cara. It is well known that when the sines are small they are proportionate to their arcs. Therefore when sine cara is fairly small, i.e. when the Eq. shadow is small, the arcs are proportionate to the Eq. shadow, i.e. the cara-vināḍīs are proportionate to the Eq. shadow. In India the Eq. shadow is fairly small, and therefore the cara-vināḍīs for different places in India can be formed by proportion, using the Eq. shadow. In higher latitudes like places North of the Himalayas, the shadow increasingly becomes greater, and the inaccuracy of using the given method will gradually increase. Example 5. (a) Eq. Shadow 5, Sun rā. 2-10-0. Find the day-time. (b) The Eq. shadow is 7, the Sun is in rāśis 7. Find the day light. (a) The cara-vināḍīs are 5(20 + 16½ + 2¼) = 5 × 38¾ = 194. As the Sun is in the 6 rāśis, Meṣa etc., the day-time is greater than 30 nāḍīs, and, therefore, the day-time is 30 nāḍīs + 194 vināḍīs = 33-14 nāḍīs. 11a. A.B. मेषादिषडुपचितं (B2. ॰ष्ट॰; B2. चितं) 12a. A1. हिमापरि धौ; A2. B1.C. हिमाद्रिपरिधौ; b. A.B. कर्कटाद्येषु. C. ॰षु [च] तद्. A. चयमितै B2.3. हिमद्रिपरिधौ c. A.B. साद्येने; C. स्याद्येन c-d. A2. यथैतस्पष्टं; B2.3. तथैतत् d. B. तुलाद्येषुकु. A.C.D. ॰षु वैषुवतात्; B. ॰षु वैषुवनात् d. A1. तछेद्यके