वेदों की प्राचीनता एवं काल-निर्णय / ओरायन (लोकमान्य बाल गंगाधर तिलक - खगोलीय वैदिक शोध)

56 THE ARCTIC HOME IN THE VEDAS. a nycthemeron never exceeding, as in the previous case, a period of twenty-four hours. As the sun passes from the northern into the southern hemisphere, the night will begin to gain over the day, until, after four months of such succession of ordinary days and nights, it terminates into the continuous night of two months mentioned above. The same description applies, mutatis mutandis, where the long night may last for 3, 4 or 5 months, until we reach the Polar condition of a day and a night of six months each, when the intermediate succession of ordinary days and nights will vanish. * We have seen that a long dawn of two months is a special and important characteristic of the North Pole. As we descend southward, the splendour and the duration of the dawn will be witnessed on a less and less magnificient scale. But the dawn, occurring at the end of the long night of two, three or more months, will still be unusually long,

• Cf. Bhaskarâcharya's Siddhânta Shiromaṇi, Golâdhyâya, Chapter VII., verses 6-7, which are as follows:— षट्षष्टिभागाभ्यधिकाः पलांशाः यत्राथ तत्रास्त्वपरो विशेषः॥ लंबाधिका क्रांतियदर्क च यावत्। तावद्दिनं संततमेव तत्र। यावच्च वाम्या सततं तमिस्रा। ततश्च मेरौ सततं समार्धम्॥ "There is a peculiarity at the place, where the latitude is great- er than 66° N. Whenever the northern declination of the sun exceeds the complement of the latitude, there will be perpetual day, for such time as that excess continues. Similarly, when the southern (de- clination exceeds), there will be perpetual night. On Meru, therefore, there is equal half-yearly perpetual day and night." Thus if the la- titude of a place be 70°, its complement will be 90—70=20°; and as the sun's height above the celestial equator (that is, his declination) is never greater than 23° 28′, there will be a continuous day at the place, so long as the declination is greater than 20° and less than 23° 28′, and there will be a similar continuous night when the sun is in the southern hemisphere. Paul Du Chaillu mentions that at Nordkyn or North Cape (N. lat. 71° 6′ 50″), the northernmost place on the conti- nent of Europe, the long night commences on 18th November, and ends on 24th January, lasting, in all, for 67 days of twenty-four hours each.