in Ptolemy's Almagest, in stating observations of eclipses.

The Metonic and Calippic periods undoubtedly imply a very considerable degree of accuracy in the knowledge which the astronomers, to whom they are due, had of the length of the month; and the first is a very happy invention for bringing the solar and lunar calendars into agreement.

The Roman calendar, from which our own is derived, appears to have been a much less skilful contrivance than the Greek; though scholars are not agreed on the subject of its construction, we can hardly doubt that months, in this as in other cases, were intended originally to have a reference to the moon. In whatever manner the solar and lunar motions were intended to be reconciled, the attempt seems altogether to have failed, and to have been soon abandoned. The Roman months, both before and after the Julian correction, were portions of the year, having no reference to full and new moons; and we, having adopted this division of the year, have thus, in our common calendar, the traces of one of the early attempts of mankind to seize the law of the succession of celestial phenomena, in a case where the attempt was a complete failure.

Considered as a part of the progress of our astronomical knowledge, improvements in the calendar do not offer many points to our observation, but they exhibit a few very important steps. Calendars which, belonging apparently to unscientific ages and nations,

possess a great degree of accordance with the true motions of the sun and moon, like the solar calendar of the Mexicans, and the lunar calendar of the Greeks, contain the only record now extant of discoveries which must have required a great deal of observation, of thought, and probably of time. The later improvements in calendars, which take place when astronomical observation has been attentively pursued, are of little consequence to the history of science; for they are generally founded on astronomical determinations, and are posterior in time, and inferior in accuracy, to the knowledge on which they depend: still, cycles of correction, which are both short and close to exactness, like that of Meton, may perhaps be the original form of the knowledge which they imply; and certainly require both accurate facts and sagacious arithmetical reasonings. The discovery of such a cycle must always have the appearance of a happy guess, like other discoveries of laws of nature. Beyond this point, the interest of the study of calendars, as bearing on our subject, ceases: they may be considered as belonging rather to art than to science; rather as an application of a part of our knowledge to the uses of life, than a means or an evidence of its extension.

Sect. 6.-The Constellations.

SOME tendency to consider the stars as formed into groups, is inevitable when men begin to attend to

them; but how men were led to the fanciful system of names of stars and of constellations, which we find to have prevailed in early times, it is very difficult to determine. Single stars, and very close groups, as the Pleiades, were named in the time of Homer and Hesiod, and at a still earlier period, as we find in the book of Job 25.

Two remarkable circumstances with respect to the constellations are, first, that they appear in most cases to be arbitrary combinations; the artificial figures which are made to include the stars, not having any resemblance to their obvious configurations; and, second, that these figures, in different countries, are so far similar, as to imply some communication. The arbitrary nature of these figures shows that they were rather the work of the imaginative and mythological tendencies of man, than of mere convenience and love of arrangement. "The constellations," says an astronomer of our own time 26, seem to have been almost purposely named and delineated to cause as much confusion and incon

25 Job xxxviii. 31. "Canst thou bind the sweet influences of Chima (the Pleiades) or loose the bands of Kesil (Orion)? Canst thou bring forth Mazzaroth (Sirius) in his season? or canst thou guide Ash or Aisch (Arcturus) with his sons?"

And ix. 9. "Which maketh Arcturus, Orion and Pleiades, and the chambers of the south."

Dupuis, vi. 545, thinks that Aisch was ug, the goat and kids. See Hyde, Ulughbeigh.

26 Herschel.

venience as possible. Innumerable snakes twine through long and contorted areas of the heavens, where no memory can follow them: bears, lions, and fishes, large and small, northern and southern, confuse all nomenclature. A better system of constellations might have been a material help as an artificial memory." When men indicate the stars by figures, borrowed from obvious resemblances, they are led to combinations quite different from the received constellations. Thus the common people in our own country find a wain or waggon, or a plough, in a portion of the great bear 27.

The similarity of the constellations recognised in different countries is very remarkable. The Chaldean, the Egyptian, and the Grecian skies have a resemblance which cannot be overlooked. Some have conceived that this resemblance may be traced also in the Indian and Arabic constellations, at least in those of the zodiac 28. But while the figures are the same, the names and traditions connected with them are different, according to the

27 So also the Greeks. Homer, Od. I.

Αρκτον ἡν και ἁμαξαν επικλησιν καλεουσιν.

The northern bear which oft the wain they call.

Aρkros was the traditional name, åμaga, that suggested by the

form.

28

Dupuis, vi. 548. The Indian zodiac contains, in the place of our Capricorn, a ram and a fish, which proves the resemblance without chance of mistake. Bailly, i. p. 157.

29.

histories and localities of each country "9; the river among the stars which the Greeks called the Eridanus, the Egyptians asserted to be the Nile. Some conceive that the signs of the zodiac, or path along which the sun and moon pass, had its divisions marked by signs which had a reference to the course of the seasons, to the motion of the sun, or the employments of the husbandman. If we take the position of the heavens, which, from the knowledge we now possess, we are sure they must have had 15000 years ago, the significance of the signs of the zodiac, in which the sun was, as referred to the Egyptian year, becomes very marked, and has led some to suppose that the zodiac was invented at such a period. Others have rejected this as an improbably great antiquity, and have thought it more likely that the constellation assigned to each season was that which at that season rose at the beginning of the night: thus the balance (which is conceived to designate the equality of days and nights) was placed among the stars which rose in the evening when the spring began: this would fix the origin of these signs 2500 years before our era.

It is clear, as has already been said, that fancy, and probably superstition, had a share in forming the collection of constellations. It is certain that, at an early period, superstitious notions were associated with the stars. Astrology is of very