tinguished by a group of stars either on the ecliptic or so near it, either in the northern or southern hemisphere, as to be occultated by the moon or capable of being in conjunction with it or the planets. These constellations are called nakshatras. Naturally, some of these constellations are the same as those subsequently chosen to mark the sun's path or the signs of the zodiac. In some cases a zodiacal constellation is divided into two nakshatras. Like the signs, the nakshatras were held to represent animals or natural objects. The following is a list of them with their corresponding stars, and the object which each was supposed to represent:

Nakshatra.

1

revolution

All the zodiacal constellations are thus included in the 8. The nakshatras except Capricorn, for which Aquila and Delphinis of the are substituted. These, as well as Hydra, are a considerable moon. distance from the ecliptic, but may perhaps be nearer the moon's path, which, as already seen, slightly diverges from it. But this point has not been ascertained by me. The moon completes the circuit of the heavens in its orbit round the earth in a little less than a lunar month or 27 days 8 hours. As twenty-seven nakshatras were demarcated, it seems clear that a nakshatra was meant to represent the distance travelled by the moon in a day. Subsequently a twenty-eighth small nakshatra was formed called Abhijit, out of Uttarāshādha and Sravana, and this may have been meant to represent the fractional part of the day. The days of the lunar month have each, as a matter of fact, a nakshatra allotted to them, which is recorded in all Hindu almanacs, and enters largely into the Joshi's astrological calculations. It may have been the case that prior to the

naming of the days of the week, the days of the lunar month were distinguished by the names of their nakshatras, but this could only have been among the learned. For though there was a nakshatra for every day of the moon's path round the ecliptic, the same days in successive months could not have the same nakshatras on account of what is called the synodical revolution of the moon. The light of the moon comes from the sun, and we see only that part of it which is illuminated by the sun. When the moon is between the earth and the sun, the light hemisphere is invisible to us, and there is no moon. When the moon is on the opposite side of the earth to the sun we see the whole of the illuminated hemisphere, and it is full moon. Thus in the time between one new moon and the next, the moon must proceed from its position between the earth and the sun to the same position again, and to do this it has to go somewhat more than once round the ecliptic, as is shown by the following figure.1

9. The

week.

FIG. 2.-Revolution of the Moon round the Earth.

As during the moon's circuit of the earth, the earth

days of the is also travelling on its orbit, the
its
between the earth and the

orbit, the moon will not be

sun again on completion of its

1 Taken from Professor Newcomb's Astronomy for Everybody.

II

THE DAYS OF THE WEEK

265

orbit, but will have to traverse the further arc shown in the figure to come between the earth and the sun. When the moon has completed the circle of the ecliptic from the position ME, its position relative to the earth has become as NF and it has not yet come between the earth and the sun. Hence while the moon completes the circuit of the ecliptic1 in 27 days 8 hours, the time from one new moon to another is 29 days 13 hours. Hence the nakshatras will not fall on the same days in successive lunar months, and would not be suitable as names for the days. It seems that, recognising this, the ancient astronomers had to find other names. They had the lunar fortnights of 14 or 15 days from new to full and full to new moon. Hence apparently they hit on the plan of dividing these into half and regulating the influence which the sun, moon and planets were believed to exercise over events in the world by allotting one day to each of them. They knew of five planets besides the sun and moon, and by giving a day to each of them the seven-day week was formed. The term planet signifies a wanderer, and it thus perhaps seemed suitable that they should give their names to the days which would revolve endlessly in a cycle, as they themselves did in the heavens. The names of the days are:

The termination vāra means a day. The weekdays were similarly named in Rome and other countries speaking Aryan languages, and they are readily recognised in French. In English three days are named after the sun, moon and Saturn, but four, Tuesday, Wednesday, Thursday and Friday, are called after Scandinavian deities, the last three being Woden or Odin, Thor and Freya. I do not know whether these were identified with the planets. It is supposed that the Hindus obtained the seven-day week from the Greeks.2

1 The moon's orbit is really an ellipse like that of the earth and all the

planets.

2 Barnett, op. cit. p. 190.

10. The

lunar

year.

II. Inter

calary months.

Four seven-day weeks were within a day and a fraction of the lunar month, which was the nearest that could be got. The first method of measuring the year would be by twelve lunar months, which would bring it back nearly to the same period. But as the lunar month is 29 days 13 hours, twelve months would be 354 days 12 hours, or nearly eleven days less than the tropical solar year. Hence if the lunar year was retained the months would move back round the year by about eleven days annually. This is what actually happens in the Muhammadan calendar where the twelve lunar months have been retained and the Muharram and other festivals come earlier every year by about eleven days.

In order to reconcile the lunar and solar years the Hindus hit upon an ingenious device. It was ordained that any month in which the sun did not enter a new sign of the zodiac would not count and would be followed by another month of the same name. Thus in the month of Chait the sun must enter the sign Mesha or Aries. If he does not enter it during the lunar month there will be an intercalary Chait, followed by the proper month of the same name during which the sun will enter Mesha.1 Such an intercalary month is called Adhika. An intercalary month, obtained by having two successive lunar months of the same name, occurs approximately once in three years, and by this means the reckoning by twelve lunar months is adjusted to the solar year. On the other hand, the sun very occasionally passes two Sankrants or enters into two fresh signs during the lunar month. This is rendered possible by the fact that the time occupied by the sun in passing through different signs of the zodiac varies to some extent. It is said that the zodiac was divided into twelve equal signs of 30° each or 1° for each day, as at this period it was considered that the year was 360 days.2 Possibly in adjusting the signs to 365 odd days some alterations may have been made in their length, or errors discovered. At any rate, whatever may be the reason, the length of the sun's periods in the signs, or of the solar months, varies from 2 Brennand's Hindu Astronomy, p.

о

1 The Indian Calendar, by Messrs. Sewell and Dikshit, pp. II and 25.

100.