sumably part of the great ocean stream, where similar sounds could be heard at his rising. The light of the stars was in like manner extinguished when they dipped into the western waves. The poets figured the sun as a god, crowned with rays, who dashed at headlong speed across the sky, in a car drawn by four beautiful white horses, which breathed fire from their nostrils.

But how did the sun, which set in the west, get back to the east at dawn? He did not descend beneath the earth and shine amongst the dead, though he once threatened to do so. Hephæstus, the divine smith, had fashioned for him a huge golden bowl, in which he slept at night, as he floated down the ocean current, until he arrived once more in the far east.

The attention of primitive man was early arrested by the striking appearance of the constellations of the heaven, groups of stars whose forms suggested the rude outlines of the wild beasts that he was accustomed to hunt in the forest. Fancy painted in these outlines on the canvas of the sky, adding many details, and inventing many fables to account for the periodical appearance of these mysterious phenomena of the night.

The most conspicuous and familiar of all the constellations was that known as "The Great Bear." Something seemed to distinguish it from the other important groups of stars in the northern sky, for night after night it appeared to move in a circle around the pole of the heaven; at one season high overhead, at another low down in the sky, but, unlike so many other constellations, it never dipped below the horizon or disappeared entirely from view. And so the Greek navigators used to steer by the Great Bear, because it indicated very roughly the position of the pole. The Phoenicians, who were better seamen and more fully acquainted with the movements of the stars, discovered, at a very early period, that the true pole of the heavens was more nearly indicated by the constellation of "The Little Bear" (which includes our "Pole-star"), and directed the course of their swift ships by observing the latter group. It is, perhaps, necessary to explain what the Greeks meant by the Pole. The earth, of course, had no poles in those days, for it was a plane surface (so at least men believed). Their word oλos meant a ball, and was applied originally to the whole vault of heaven, and, later on, to that part of it which appeared most distant from the earth. Hence it came to mean the pivot on which the celestial hemisphere appears to revolve. The Pole-star is so near this imaginary pivot that it describes only a very small circle in the twenty-four hours, and, to all intents and purposes, it is the one fixed point of the sky. Science has taught us

that this apparent revolution of the heaven is caused by the actual rotation of the earth upon its own axis, and that the pole, or absolutely motionless point of the sky, visible to the inhabitants of the northern hemisphere, must consequently be situated immediately over the North-pole of our earth, but so far as practical knowledge of the stars goes we have not improved very much upon the methods of the old Phoenician merchantmen. Only the clouds could hide from the pilot's eye these two Bears

"Arctos oceani metuentes æquore tingi."

The Homeric poems, composed some nine centuries before Christ, show that several of the constellations were, even then, known to the Greeks by the names which they still continue to bear. Ulysses, in the "Odyssey," "skilfully steers his bark, and sleep falls not upon his eyes as he keeps them fixed upon the Pleiades, late-setting Bootes, and the Bear (also called the Waggon), which turns itself in the same place, and watches Orion, and alone has no share in ocean baths." And, in the "Iliad," old Priam compares Achilles, whom he sees advancing to slay his son Hector, to "a star which rises in summer, and whose resplendent rays shine among many stars in the dead of night. It men call the Dog of Orion. Very bright is that star, but it is a portent of ill, and brings excess of heat to miserable mortals.”

Of the constellations mentioned in the above passages, Orion was pictured as a mighty hunter, of gigantic size and strength (the Nimrod of the Greeks). Accompanied by his dog Sirius, "the scorcher," most brilliant of all stars, he advances to give the Great Bear the coup de grâce, while that huge animal seems slowly to turn at bay near the pole. The Pleiads were daughters of Atlas, chased by Orion. Their name has been derived from λɛiv, to sail, because so long as they appeared in the sky, navigation was considered safe. There was a curious tradition among the ancients, that there were once seven stars in this group. Only six are now visible to the naked eye. "Quæ septem dici sex tamen esse solebant," says Ovid. The legend founded upon this alleged disappearance of one of the component lights was that a daughter of Atlas married a mortal, and so her light was dimmed. Another cluster which is mentioned in the Homeric poems, the Hyades, or rainy stars, foretold wet weather. Later poets represent the Pleiads as a flock of pigeons, λades, and the Hyades, by a similar play upon the name, as a herd of piglings, vás, chased by the celestial hunter. Agricultural man saw in the constellation of the Great Bear the representation of a waggon or plough, and Boötes was the man in charge of its team of oxen.

One of the Hesiodic poems, "The Works and Days," composed, perhaps, a century and a half later than the Homeric, gives precept upon precept to farmer and mariner, and teaches them how to observe the seasons, at a period when almanacks are as yet unknown.

"When the Pleiads, daughters of Atlas, rise, begin your harvest ; when they set, your ploughing. When, after the winter solstice, Zeus has fulfilled sixty days of winter, then it is that Arcturus, having left the sacred stream of Ocean, rises in the twilight brightly beaming, prune your vines. When Sirius parches head and knees, and the body is dried up by reason of heat, then sit in the shade and drink. When Orion and Sirius have reached mid-heaven, and rosy-fingered dawn beholds Arcturus, then gather and carry home your grape clusters. When, flying the impetuous might of Orion, the Pleiads sink into the misty deep, then rage blasts of wind, haul ashore your ship and cover her around with stones."

The mention of the solstice here and elsewhere in the poem implies careful astronomical observation. Arcturus, "the bear-keeper," is a bright star in the constellation Boötes.

Prometheus

The Greek year consisted of three seasons only. enumerates them. "They had no sign," says he, "of winter, of flowery spring, or fruitful summer." In ancient Germany a similar division of the year prevailed, for Tacitus makes the caustic remark that, among the Germans, winter, spring, and summer have a meaning and a name, but to that people the name and blessings of autumn are alike unknown. It is not likely, then, that our Saxon forefathers were acquainted with the last-named season, and our very term autumn is an echo of the Roman tongue. It was the moon, and not the sun, which first suggested to mankind the circle of the year as a measure of time. The sun exhibits no changes of appearance, and his light obliterates all the landmarks of the sky. A luminary which is the same yesterday, to-day, and to-morrow, might give rise to conceptions of perfection and eternity, but, beyond the alternations of day and night, it could suggest to men's minds no abstract measure of time. But with our humble satellite it is far otherwise. The regularly recurring phenomena of new moon and full moon are too marked to escape the attention of the most obtuse and unreflecting of savages. The motion of the sun may be compared to that of the minute-hand of a clock, sweeping on hour after hour without leaving much record of its comparatively vast journey; the progress of the moon, on the contrary, may be likened to that of the hour-hand, which registers the movements of its companion, and resolves them into twelve welldefined periods.

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The interval between two new moons is called a lunation or synodic month, and twelve of such lunations were found to coincide very roughly with the period in which the sun returned to the goal in the sky from which he had started, and to correspond with the return of that most marked of natural phenomena, the budding of trees in spring.

But after making this important discovery the calendar-makers plunged into a slough of difficulties, from which they were long in emerging. They made the natural mistake of supposing that the year was a standard period of time, given by divine appointment to man, and that the sun and moon conspired in their operations, so as to form in effect the hands of a great natural and infallible clock, contrived and regulated by the gods themselves, for the purpose of preserving unimpaired the cycle of their own religious festivals.

But such, alas! is not the case. The tropical year, which is the period in which the sun appears to make a complete circuit of the heaven, or, to state the same thing in scientific language, the period within which the earth actually makes one complete revolution in its orbit round the sun, consists of 365 days. I am disregarding the fraction.

And so

Now the lunation (or interval between new moon and new moon, or full moon and full moon) consists of 29 days, so that twelve lunations make up a cycle of only 354 days. And so it came to pass that people who reckoned by the moon had finished their year 11 days before the sun had accomplished his full course, and the everaccumulating difference between the solar year and twelve lunations gradually shifted the first day of the civil year backward, step by step, until, if left to itself, it had made the tour of the seasons. all was confusion, the Athenians beginning their year at the summer solstice, the Spartans at the autumnal equinox. The ingenuity of man was therefore exercised in solving the problem of how, by the insertion or addition of intercalary or supernumerary days, to keep lunar time abreast of solar time. The want of perfect scientific instruments prevented the ancients from exactly hitting off to a nicety the respective lengths of the solar and lunar year, and what addition must consequently be made to the latter in order to reconcile it with the former. And so the cooking of the calendar was spoilt, as much by the uncertainty as by the number of the cooks employed in the process. They sometimes added too much, sometimes too little, of the necessary ingredient.

The old Greeks, who reckoned by the moon, made use of a year of 360 days. Their calculation was founded upon the double error

that a lunation consists of exactly 30 days (whereas it contains only 29 days, 12 hours and 44 minutes), and that twelve lunations amounting to 360 days coincide with the solar year.

Hence we learn from Herodotus that the Cilicians paid a tribute of 360 white horses, being one horse for every day in the year. One of the things which most struck the same historian, during his visit to Egypt, was the native method of regulating the calendar. Their superior knowledge of astronomy had taught the people of that country to divide the civil year into 365 days, and so make it very nearly correspond with the natural circuit of the seasons, whereas the more cumbrous Greek method was to add biennially to their standard year of 360 days an intercalary "month," equivalent to the difference between solar and civil time.

That the solar year consisted of 365 complete days was a matter of common knowledge from a comparatively early period, but there is an insidious fraction involved in the calculation, which puzzled the early astronomers and has been the cause of endless trouble to the makers of calendars.

There was a tradition among the Romans that their mythical king, Romulus, had invented a year of ten months only, and that his successor, Numa, had added two more to make up twelve.

The origin of this story appears to be that a sequence of months bore numerical names: Quintilis (July), Sextilis (August), September, October, November, December, while the two last, January and February, were not numbered. Julius Cæsar reformed the Roman Calendar in the year 46 B.C. He shifted the commencement of the year back to January 1, and, acting upon the advice of an expert from the school of astronomy at Alexandria, he fixed the length of the civil year at 365 days. The fraction of 6 hours amounted at the expiration of four years to one complete day of 24 hours, and so he ordered that every fourth year the sixth day before the calends of March should be reckoned twice. Hence the origin of the name Bissextile for leap year. It might be supposed that Cæsar's astronomical reckoning, if not absolutely perfect, was yet sufficiently so for all the practical purposes of daily life. But no! His year of 365 days was longer than the natural solar year by 11 minutes and 14 seconds, and the result was that, in the year of grace 1582, the civil time had become so fast, that while the equinox, according to the calendar, fell on March 11, the equinox de facto did not fall until 10 days later, on the 21st of the same month. Pope Gregory XIII. therefore cut ten days off the year 1582, by reckoning October 5 in that year as the 15th day of the month. But there still remained