equator, a meridian, and two tropics. It is impossible, from what we know of Hipparchus, that he could have done without something of the sort. At the same time, between Hipparchus and Ptolemy we have no observations to settle this point.

The description of Ptolemy (Syntaxis,' book v. ch. i.) is as follows:Fix two perfectly equal circles at right angles to each other, and let one represent the ecliptic, and the other the solstitial colure. In the poles of the ecliptic place cylinders, projecting within and without beyond the rims of the solstitial colure, and fix on these cylinders as pivots outer and inner circles, which shall revolve freely without and within the first-mentioned circles. These are evidently circles of longitude. Within the innermost, and in its plane, place a lighter circle, sliding by friction, and having two sights diametrically opposite, by which the latitude of any celestial phenomenon may be observed when the instrument is adjusted; that is, when the circle representing the ecliptic is in the plane of the true ecliptic. To effect this, cylindrical pivots are inserted in the solstitial colure in the points corresponding to the poles of the equator, and the whole of the apparatus is suspended within a circle which is placed in the meridian of the place of observation. The ecliptic being divided from its interior to its exterior rim, the outer of the circles of longitude is set to the division corresponding to the longitude of the sun, as given in the solar tables, and the whole

below the cylinder, the orifice of the sight being made just large enough to admit of this. The angular distance of the sight from the equatorial circle is then the declination of the star. To measure the difference of right ascension of two stars, two observers take two sights on the equator, which they adjust till each sees his star just on the axis, both on one side of it and the other. The angular distance of the sights is then the difference of right ascension of the stars.

The plumb-line shows whether the meridian is exactly vertical, and the screws at the feet are employed to raise or lower either end when necessary. We give one more step between the ancient and modern instruments, from the same work of Tycho Brahé.

is then turned round the poles of the equator, until the plane of the ecliptic and the plane of the outer circle of longitude pass through the sun. The instrument is then adjusted, the inner circle of longitude and its sliding limb with sights is turned to the moon, and the angle read off upon this circle is the latitude of the moon, while the angle read off on the interior edge of the ecliptic is the longitude.

When stars are observed, it is sufficient to make the plane of the outer circle of longitude pass through the moon or any known star after setting that circle to the known longitude of the moon or star. The observation then takes place as before.

No material improvement upon this construction appears to have been made by the Arabs, who in some instances used very large instruments of the kind. A more skilful variety of the astrolabe is here shown, described by Tycho Brahé, from whose 'Astronomia Instaurata Mechanica' the preceding cut is taken.

The outermost circle represents the meridian; the axis passes through the poles, and there is a revolving equator and hour-circle fixed together. The sights on the circles are moveable; but instead of using opposite sights, the small cylinder which projects from the axis is employed. For example, to measure the declination of a star, the hour-circle is moved till it passes through the star, and a sight is then placed so that the star may be seen through it on the edge of the cylindrical pin which projects from the centre of the axis, both on looking above and

The hour-circle is now disengaged from the equator and independent of it. The polar axis is directly supported, and not made to depend upon the position of the meridian. This is perhaps sufficiently near to the modern equatorial to be considered as the first instrument of the kind.

ASTRO'LOGY. If this word were used in a sense analogous with that of geology or theology, it would mean simply the science of the stars; while astronomy might mean the science of their order and arrangement. But the term, at least when coupled with the epithet judicial, has always signified the discovery of future events by means of the position of the heavenly bodies. The two words astrology (aorpoλoyía) and astronomy (aarpovouía) seem to have been used in the same sense by the Greeks, at least till about the Christian era. Cicero (Offic.' i. 6.) uses the word astrologia to express astronomical knowledge. It has long been unusual to produce any arguments against this pretended science; but there are two considerations which make us think it may be useful to show those who are unacquainted with it a few of its details. The first is, that works, seriously professing to inculcate and defend the principles of astrology, have been published within the last twenty years in this country, and are still sold, almost exclusively, by some booksellers: the second, that several of our most popular almanacs do actually give astrological predictions at the present time. This may be a mere matter of amusement with the more enlightened; but we are afraid there are some who play with edgetools in reading the fooleries of the works alluded to. The love of the marvellous is not under proper regulation, even in the minds of many who do not go the length of supposing astrology credible; and we shall therefore perhaps do good service in showing what the system really is, and what consequences its adoption must lead to.

It must moreover be remembered that our old English writers, particularly the dramatists, cannot be well understood without some information upon the leading terms and principles of this art; which therefore may be as lawfully studied as the history of Jupiter and the Metamorphoses of Ovid.

proper positions in the houses; thus Mercury () appears to be in the twelfth house, at 22° 46' from the boundary of the eleventh and twelfth. But, on all the preceding points, it must be observed that great authorities differ very much. From among the obscurity and confusion which prevail in old treatises, we are able to collect this much, that some of them draw the boundary lines of the houses in such a way as to cut the ecliptic into twelve equal parts, instead of the prime vertical, as we have done; others draw the boundaries through the poles, instead of the north and south points of the horizon. The future destinies of mankind are rendered very uncertain by such diversity of opinion; but this we have found, that the followers of each system complain just as much of the rest, as if they had some reason to show for their own. For instance, Peletarius, or Pelletier, who introduced algebra into France, and wrote on the horoscope in 1563, expresses himself thus: "Some cut the horizon into equal parts, some a vertical circle, some the equator, some the ecliptic, some a parallel: whence it is not wonderful that a difficult art should be involved in fresh obscurity; for who can possibly see a living likeness in a mirror which is put out of shape in so many ways?" His own system is the equal division of the zodiac; and his argument for it, independently of old authorities, is the incongruity of letting the poles of the ecliptic have nothing to do with a matter which so nearly concerns the zodiac. Minimeque convenit, zodiaco suos polos esse inutiles in eo negotio quod zodiaco maxime proprium est. The placing of the signs in the equator he treats as a dream, and seems perfectly satisfied with the preceding reason.

The science which, under the name of astrology, or some term of equivalent meaning, found universal belief among all the nations of antiquity except the Greeks, and also prevailed through the whole world of the middle ages, is based upon the supposition that the heavenly bodies are the instruments by which the Creator regulates the course of events in this world, giving them different powers according to their different positions. This is the description of the more learned astrologers; for we need hardly say, that the ignorant have made the stars themselves the agents, just as the image of the Deity has generally come in time to be regarded by the vulgar as the Deity himself. Looking at the more credible description, it might be philosophical for a newly created being, in possession of rational powers, to suspend his opinion on such a point till he had observed facts enough to affirm or deny the connection asserted to exist between the places of the planets and his own fortunes. That there is nothing repugnant to human nature in the basis of astrology is sufficiently proved by the number of great minds which have been led by it, when properly prepared by education; and the present age must recollect that the arguments which are now held conclusive against astrology get their strength in the minds of most people from no other circumstance than that which formerly was the prop of considerations which were held equally decisive in favour of it, namely, the bias of education. The real arguments against astrology are, first, that it is self-contradictory; secondly, that its predictions are not borne out by facts. To see the first of these, we must describe the leading principles of the art.

In the following globes, the circle projected horizontally represents the horizon, the double circle the meridian, and the other four circles are drawn at equal distances from the meridian and horizon, through the north and south points of the latter, thus dividing the whole IX. X.

The houses have different powers. The strongest of all is the first, which contains the part of the heaven about to rise: this is called the ascendant; and the point of the ecliptic which is just rising is called the horoscope. The next house in power is the tenth, which is coming on the meridian, &c. The first is the house of life; the second, of riches; the third, of brethren; the fourth, of parents; the fifth, of children; the sixth, of health; the seventh, of marriage; the eighth, of death; the ninth, of religion; the tenth, of dignities; the eleventh, of friends; the twelfth, of enemies. Each house has one of the heavenly bodies as its lord, who is stronger in his own house than in any other, as is but fit; and of two planets equally strong in other respects, he who is in the strongest house is the stronger. Now conceive all plants, animals, minerals, countries, &c., parcelled out under the different planets, which exercise their influence in abundance of different ways, according to the houses they may happen to be in for the time, and their positions relatively to each other-the result will be as good an idea of the mysteries of astrology as it is worth any body's while to obtain. We shall now give some examples of the application of the science; and this we do principally, because in the mystical announcements which issue from our press, the darkness of the hints which are given and is not sporting too much with the credulity of the age, or with the throw a poetical gloom over the subject. This no doubt is interesting, chance of detection; but it is a foul libel on the powers of astrology. Thus, in 1815, instead of announcing some such prediction as the following "Mars in the house of death portends, we are afraid, some the new order of things; but, if we mistake not, the conjunction of new disasters by war or other cause; a personage will strive against Luna and Saturn in the twelfth house bodes him no good,”—instead, we say, of such an unsatisfactory prophecy, a real believer in astrology, such as it was before it fell from its high estate, might have traced Napoleon from Elba to Waterloo, have calculated the very moment of the advance of the Prussians, and described the sword-knot of the captain of the Bellerophon. Thus we have the story of a Jew, in the time of the Caliph Al Mansur, who was able to detect, by means of the heavenly bodies, that certain words just written upon a paper, which he was not allowed to see, were the names of a plant and an animal. But lest any one should imagine that perhaps the later astrologers have given up the attainment of information so minute, and have confined themselves to such general indications as those of our almanacs, which, as they mean nothing, may as reasonably be drawn from the stars as elsewhere, we take the following instances from a work published in 1817, which we will not name, and which we would willingly suppose to have been written in irony, if it were not that its size (2 vols. 4to, with tables) and style are both evidences either of real belief or intentional attempt to deceive.

heavens, visible and invisible, into twelve equal parts. These circles are supposed to remain immoveable, while the diurnal revolution of the globe takes place under them. The twelve divisions are called the twelve houses of heaven, and are numbered in the order in which they would rise, if the circles accompanied the diurnal revolution. Every heavenly body passes through the twelve houses in twenty-four hours, but is not always in the same house with the same stars, except at the equator. For it is evident that, in order to have two bodies always in the same house, the revolution must take place round the north and south poles of the heavens, which poles are in the horizon only to a spectator on the equator itself. The principal point attended to in each house is the part of the zodiac which occupies it; and the place of any planet in the house is the distance of the body from the cusp, or boundary circle, measured on the zodiac. The following fanciful method of represent ing the twelve houses was in universal use, and the readers of almanacs must be familiar with it.

A man was born June 24, 1758, at eight minutes after ten in the morning, committed a murder, and was by many supposed to be insane. Pending his trial, an astrologer was requested to point out by the stars whether this defence would be established or not. The

nativity was cast; that is, the position of the heavens at the aforesaid time was laid down, and the nativity having been rectified (a process amounting to giving the prophet a power of making almost any change he pleases), the result was as follows:

Mercury being lord of the ascendant, irradiated by a malefic quartile aspect of the planet Mars, and afflicted by an opposition with Jupiter, declares that the native shall be involved in an abyss of troubles and afflictions, even to the hazard of his life."-" The quartile of Mercury and Mars, particularly when Mercury is constituted principal significator, hath implication of high crimes and misdemeanors."

The twelve triangles represent the twelve houses of heaven, as marked by the Roman numerals. The time is April 16, 1784, at half past six in the morning. On the boundary of each house is written the part of the ecliptic which is to be found on it. For instance, on the cusp of the twelfth house that is just rising is the point of the ecliptic which is in 4° 14′ of Gemini. The boundary between the ninth and tenth houses is in 1° Aquarius. The whole sign of Scorpio is in the sixth house, the boundaries of which are therefore in Libra and Sagittarius. The planets are placed in their

"Upon a further inspection of the figure, we find a baneful quartile aspect of Mars and Jupiter, with a mischievous opposition of Saturn

and Mars. To the first of these we are to attribute the dissolute manners of the native."-" Here is unquestionably a favourable trine of the Sun and Saturn; but no great good can result from it, because the Sun is lord of the twelfth house, posited in the tenth, and out of all his essential dignities: at the same time that Saturn is lord of the sixth, located therein, and both the significators are under the dominion of the evil genii, vitiating the mind and affections of the native.”—“ At the time the unhappy native was prompted to commit this barbarous act, the Moon came to an opposition of Mars by direct direction, while she occupied the cusp of the seventh house, which represents the unfortunate woman."-" The Sun I find to be giver of life, posited in the tenth house, the house of justice; Mercury, lord of the ascendant, being in Gemini, an airy sign, and the Moon likewise in an airy sign, show the manner of the native's death, that he would die suspended in the air; while the opposition of four planets in the radix, and the mundane quartile of the Sun and Mars from the tenth, the house of justice, show the quality of it-namely, that it should be in due course of law, by the hands of the common hangman, and not by suicide.""I brought up the direction of death with great nicety and precision, and found he would be plunged into eternity when the Sun came to the anaretical point of the midheaven, and met the noxious beams of the Moon and Mars in opposition, which thus constituted is ever productive of a violent death."

We now give the following opinion upon a case of a projected marriage, in which the lady, suspecting an attachment elsewhere on the part of her intended husband, inquires whether it will ever take place. The position of the heavens is supposed to be laid down at the moment of asking the question.

"The Sun is significator of the lady; and Saturn, lord of the seventh house, is significator of the gentleman. It must also be observed, that in this, and all questions relative to matrimony, Mars and the Sun are the natural significators of a woman's marriage; and Venus and the Moon are those of a man's. Now Saturn, the gentleman's significator, is remarkably well posited in the fifth house, and has Venus within his orb, applying to him by conjunction; which is a very powerful indication that his affections are sincere and honourable, and that his mind is fully bent to the marriage state. The Sun, likewise, being in a sextile aspect with Mars, the lady's significator of marriage, plainly shows her inclination to matrimony to be strongly fixed, and her affections to be perfectly sincere.

"The next thing to be considered is, whether there be any frustration or impediting aspect between these significators, and I find the Moon and Venus, the gentleman's significators of marriage, are applying to a quartile aspect with each other. This is an evident proof that the marriage is prolonged by the interference of some other woman of this gentleman's intimate acquaintance, because the aspect is made in a feminine sign; but as the Moon, in separating from Venus, applies to a perfect trine with Mars, the querent's principal significator of marriage, and also to a sextile of the Sun, her natural significator in the figure, it totally removes the evil effects of the malefic aspect, and leaves the path free and unobstructed to the gates of Hymen. This opinion is greatly strengthened by considering the mode in which their significators are severally disposed. Saturn disposes of the Sun, who is posited in the terms of Venus; and Venus, Saturn, and the Moon, are all disposed of by the benevolent planet Jupiter, who is himself disposed of by Mars, the principal significator of this lady's marriage, and who thus triumphs over every obstacle to the celebration of their nuptials. I therefore could not hesitate in declaring to the lady, in the fullest and most satisfactory terms, that the gentleman who courted her had a sincere and tender regard for her; and that, though some circumstances might have happened rather unfavourable to her wishes, yet she might rest perfectly assured that he was the man allotted to be her husband.

"Apparently well satisfied with these declarations, she proceeded to inquire in what length of time this desirable circumstance might come to pass. To gratify her wishes in this particular, I referred again to the figure where the Moon wants upwards of eleven degrees of forming a perfect sextile aspect with the Sun, the lord of the ascendant, and the same to Mars, her significator of marriage, and, therefore, by converting the degrees into time by the rule heretofore given, I fixed her marriage at about the end of three months, assuring her it could not exceed that time."

On looking at the examples we have chosen, we see that they refer to matters which are proverbially under the control of destiny. We therefore take another, which has more connection with the common affairs of life. It consists of directions for dealing in the smaller sorts of cattle, such as sheep, hogs, &c., and will fully explain the risk of such speculations.

"If the lord of the sixth and the lord of the second are in conjunction, in a good house of heaven, the querent may thrive by them (that is, small cattle); or if they be in sextile or trine, the same. The lord of the sixth, casting a friendly aspect to the part of Fortune, or being in good configuration with the dispositor thereof, denotes much good to the querent by dealing in small cattle; but if, on the contrary, the lord of the sixth be unfortunate, and in evil aspect with the lord of the ascendant or second, or cast malignant rays to either of their cusps, the querent will lose by dealing in small cattle. If the lord of the sixth be in quartile, or in opposition to the dispositor of the part of

ARTS AND SCI. DIV. VOL. I.

Fortune, or the Moon, the querent cannot thrive by dealing in small cattle. The same if the lord of the sixth be afflicted either by Saturn, Mars, or the Dragon's Tail; or be found either retrograde, combust, cadent, or peregrine. The Dragon's Tail and Mars show much loss therein by Knaves and thieves, and ill bargains, &c.; and Saturn denotes much damage by the rot or murrain."

The

That the ancient system of astrology contained the most contradictory assertions may be made evident in very few words. position of the heavens at the time of birth settled every man's character of body and mind, the various fortunes he would meet with, and his relative positions with regard to friends and enemies. Thus, every one who was born at or very near the same time as Alexander the Great, in the same country, would have a right to expect a somewhat similar career; and twin brothers could never fail to have the same horoscope, and therefore the same success in life; and though the subject of a particular horoscope should travel over the whole world, and thereby come under the influence of positions of the heavens which never could have occurred at his birthplace, yet these would be always ready to tell him (when properly looked at) whether the present moment was favourable or unfavourable to any pursuit he had in view. To take a case that might have occurred: suppose two men had engaged to throw dice against each other for their whole fortunes, and that each went the night before to consult different astrologers in the same town. To them it would not be necessary to tell their names or exhibit their horoscopes; the present position of the heavens would be sufficient for pointing out a favourable hour, and if both astrologers worked by the same rules, as they ought to do, they would both arrive at the same result; that is, the same would be recommended to both inquirers, though one of them must certainly lose.

The astrologers never made any allowance for the precession of the equinoxes. Thus, though the constellation Aries is now in the sign Taurus, and the influences of its stars ought to have moved with them, we find that the astronomical Aries, or the first thirty degrees of the ecliptic, is used for the constellation. Under the circumstances, this is of little consequence; but such a practice would be fatal to astronomy. That observed facts did stubbornly refuse to fulfil the predictions of the planets need hardly be told. In the 15th century, Stoffler foretold a universal deluge which should take place in 1524, in consequence of three planets being then in conjunction in a watery sign. All Europe was in consternation; and those who could find the means built boats in readiness. Voltaire mentions a doctor of Toulouse who made an ark for himself and his friends. Such a circumstance shows the hold which astrology had upon men's minds, from which, had it been true, it never could have been forced; for although a new truth, even when capable of easy verification, is introduced with difficulty, it is altogether absurd to suppose that a science, the correctness of which was of every-day experience, should drop and become exploded, not for want of cultivators, but of believers. The former we have, perhaps, even now, and a few of the latter, though only among the most ignorant of the community. The art is at present under the ban of the law, in order that designing persons may have at least one access stopped to the pockets of the credulous. By the Statute of the 1st of James I., c. 12, sorcery of all species was prohibited, though it does not appear certain that this term included astrology; but by the Vagrant Act, 5 Geo. IV., c. 8, sec. 4, all "persons pretending to tell fortunes, or using any subtle craft, means, or device, by palmistry or otherwise, to deceive and impose upon any of his Majesty's subjects," are rogues and vagabonds-that is, punishable by any magistrate, with three months' imprisonment and hard labour.

The history of judicial astrology, at least up to the middle of the 15th century, is very nearly that of astronomy, since the latter branch of the science, except among the Greeks, was mostly cultivated for the sake of the former. Hence to it, as to alchemy, we owe many really useful discoveries. It is a singular fact, that the first lunar tables which were constructed on the Newtonian theory were intended to be subservient to the calculation of nativities; there is no question that the necessity which the astrologer lay under, of being ready, at any moment, to lay down the positions of the heavenly bodies, produced great numbers of useful tables and observations; and the Greek works which have been preserved by the Arabs were valued principally for the use to which their mathematics could be turned in astrology. The origin of the science is beyond the reach of history, nor is it much worth while to collect all that is known on this point. It certainly came into Europe from the East, where it is mentioned in the earliest records of every nation. The Chinese are said to have placed it on the same footing with agriculture and medicine: the Chaldeans cultivated it sedulously, and the invention is attributed to them by Suidas (cited by Montucla, iv. 372). The Hindoos have long regulated the most important actions of their lives by the stars (see introduction to the Lilliwati'); but Mr. Colebrooke has shown (Hindoo Algebra,' preface, p. 80) that several of their fundamental terms are not Sanscrit, from which he apparently leads us to conclude that he thinks the science neither ancient nor indigenous in India. Among the Egyptians it was of great antiquity; but it is not mentioned in the books of Moses, unless included in magic or sorcery, which is most probable.

The books of Isaiah and Jeremiah allude directly to astrology in

UU

inequality, whose law and approximate magnitude it gives, should be found in the motion of a certain body, if the Newtonian principle be correct. On being looked for in the manner which the nature of the inequality itself shows to be most advantageous, it is found accordingly, and its exact magnitude, as ascertained by observation, is often of use in correcting that obtained from theory. For example, had it not been for methods of this kind, our knowledge of the motions of Jupiter's satellites, which is yet far from mature, would have been in a state of the merest infancy.

If the theory had arrived at a degree of completeness, towards which it has been and is rapidly tending, nothing more would be necessary for the determination of the motions of the solar system than the knowledge of the actual positions, velocities, and directions of the velocities of the bodies composing it, at some one moment, or of any other quantities in which the above were mixed up, and from which they could be obtained by calculation. But up to the present time it has been necessary to use more data of observation than the preceding, and it is only in recent years that tables of the moon, from the first mentioned data alone, have been published,

our æra.

For the details of the actual state of astronomy we must refer the reader to such articles as STARS; SOLAR SYSTEM; &c., and the names of the several planets. We shall now proceed to a sketch of the history, or rather the annals, of astronomy, referring for fuller information to the list of works given at the end of this article. The real history of written astronomy, that is, of actually recorded and moderately correct observations in sufficient number to constitute a body of science, commences with Hipparchus, about 160 years before Prior to his time, it is difficult to do more than speculate upon the few facts which are left to us. That astronomical observation of a certain description began in the very earliest ages, there can be no doubt; but here there could be but one instrument, the horizon, and but one theory, the actual motion of the heavenly bodies round the earth. The earliest observations mentioned are those of the rising and setting of stars, which led to the registration of the different appearances presented by the heavens in the course of a year, to which may be added lunar and solar eclipses and comets. The rapid motion of the moon in the heavens would probably have caused the lunar zodiac to be first marked out, though it is clear that the solar zodiac was of a very early date. Astronomical observation has always been one of the accompaniments of civilisation, both in modern and ancient times; and however much we may conceive ourselves entitled to look down upon the notions of our predecessors, we must not forget that in speaking of any country which possessed an astronomical theory worth so much as laughing at in modern times, we place that country in the list of exceptions to the rule which prevailed through the greater number. If the Chaldean system appear insufficient or the Ptolemaic complicated, these are yet real results of thought, and, to a certain extent, actual representations of fact. Mungo Park mentions an African tribe, whose opinion it was that the inhabitants of the west fried the sun when he got down to them, and after heating him sufficiently for next day's service, took him round by a private passage to the east. If we could collect the astronomy of the whole ancient world, there can be little doubt that the comparatively humble efforts to which we are coming would appear miracles of sense and reflection, among theories not much superior to those of Park's Africans.

The nations who are known to have cultivated astronomy before the Christian era are the Chinese, Indians, Chaldeans, Egyptians, and Greeks. The first made it a matter of politics, the three next of religious observance, and all four applied it to astrology. Among the Greeks only, the science had no reference either to politics, religion, or soothsaying; and here it throve with a vigour which permits us to make the astronomy of Hipparchus and Ptolemy a part of the chain which ends with Newton and Laplace. What we know of the four first-mentioned nations is not sufficiently certain or definite to warrant our drawing very positive conclusions as to the time when they began to study the science; and the question is rendered the more difficult by the pretensions to antiquity which have been advanced in favour of each by well-informed men of modern times. Each nation has its advocates, who maintain that the Chinese, the Indians, the Chaldeans, or the Egyptians, were the first astronomers: which is of itself sufficient to prove that the question is doubtful. Fortunately it is of little consequence; and also the astronomy of the first and two last is of a character and extent which will justify our saying that, be it very ancient or not, there is nothing on the face of it which needs the supposition of any very long time having been expended upon it. The Hindoo astronomy, on the other hand, though certainly more extensive and correct, may have been, for anything that can be shown to the contrary, received from the Arabs of the middle ages. At least such is the opinion of Laplace, Delambre, and several celebrated AngloIndians, who have had means of knowing more of the subject than either. But this question is one of difficulty, and ought not to be considered as finally settled.

The Chinese have some annals which were translated by De Mailla, a Jesuit missionary at Pekin, 1777-1785. They claim to go back to the year B.C. 2857; but of astronomical phenomena they record hardly anything, except eclipses of the sun and the appearance of comets, and of the former nothing but the fact and the day of their happening. They state that the astronomers by profession were obliged, on pain of

death, to predict every eclipse that occurred, and that, even after such phenomena were found capable of prediction, it was the practice to shout, beat drums, &c., during every eclipse, to frighten away the monster which they supposed to be devouring the sun. The mathematicians, in spite of their responsibility, were forbidden to make any alteration in their theories or methods, without the consent of the emperor. The loss of many methods, asserted to have been formerly practised, is attributed to the burning of all scientific books by one of their princes, B. C. 221. But perhaps the loss was not great; for Gaubil, who recalculated their asserted eclipses, could not verify more than one of a date anterior to the time of Ptolemy; and even that one is doubtful. The fact of the motions of the planets was known to the Chinese, but not the precession of the equinoxes, till about A.D. 400. They had also the Metonic and Calippic periods.

The question with regard to the Hindoos is not whether their astronomy is sufficiently high in its pretensions to make it worth while to inquire into its antiquity, but whether an astronomical system of a very advanced character, which certainly was found among them, is or is not as old as they assert it to be. This system is found in certain tables, called the tables of Tirvalore, which have been brought into Europe by Le Gentil, and in an original work, the Surya Siddhanta,' of which an account will be found under VIGA GANITA, in the BIOG. DIV.; and it may be fairly considered as about equal to the European system of the 12th century. The epoch claimed by the tables is B.C. 3102, the beginning of the Cali-yug, or iron age of Hindoo mythology, at which time a conjunction of all the planets is asserted. But this has too figurative a character; and moreover, the elements of the tables are hardly such as would have been derived from observations actually made at that period. That the epoch is fictitious may be readily believed; but the question is, was this fictitious epoch formed by Hindoos from their own observations before the Christian era, or was their system introduced by the Arabs, or by direct communication with the Greeks? On the one hand it is argued that the Indian tables, being in many respects a mean between those of Ptolemy and Albategnius, may have been derived from those two; on the other hand, the remarkable correctness of several points, and the known character of the people in question, whose advances in mathematics cannot be doubted, and whose habits have, throughout recorded history, induced them to repel all connection with foreigners, are urged in favour of the originality of their system. Those who are curious may consult Bailly's Hist. de l'Astronomie Indienne,' on the one hand, or Delambre, on the other; but this question has unfortunately been treated with considerable spirit of system on both sides.

The Chaldeans, according to Diodorus, had long observed the risings and settings of the heavenly bodies, as well as eclipses. They had the celebrated Metonic period of nineteen years, and it is supposed that Meton obtained it from them, though this point is doubtful. They had also other periods, the meaning of which has caused discussion. [SAROS, NEROS, Sosos.] Simplicius, a commentator on Aristotle, and also Porphyry relate that a series of eclipses preserved at Babylon was transmitted by Alexander to Aristotle, and contained the observations of 1903 years preceding the conquest of Babylon by the Macedonians. But Ptolemy gives only a few of them, the earliest of these not reaching higher than B.C. 720. They are of the roughest kind, the times being given only in hours, and the part of the diameter eclipsed within a quarter; but nevertheless they are the earliest trustworthy observations we possess, and led, in the hands of Halley, to the discovery of the acceleration of the moon's mean motion. We find also among the Chaldeans the use of the clepsydra as a clock, of the gnomon as an instrument for measuring solstices, and of the hemispherical dial called by the Greeks σkápn, for ascertaining the positions of the sun. By the clepsydra they were enabled to divide the ecliptic nearly into twelve equal parts, and are thus said to have invented the zodiac.

The Egyptians have left us no observations, and few astronomical relics, the meaning of which can be made very clear, though it is probable that they were the first instructors of the Greeks. Their year was of 365 days: for their method of correcting it, see SOTHIAC PERIOD. They observed eclipses, but none have come to us; they foretold comets, according to Diodorus; but as this author also mentions at the same time that they foretold future events, it becomes doubtful whether we are to understand that their predictions were successful. The idea attributed to them that Mercury and Venus moved round the sun is not mentioned by Ptolemy; whose silence on this and many other points, writing as he did in Egypt, is remarkable, unless it be admitted at once as a proof of exaggeration in the preceding accounts. The correct manner in which some of the pyramids are said to be placed north and south has always been quoted as a ground of suspicion, that these buildings had some astronomical use. The zodiac has also been attributed to the Egyptians. [DENDERAH, ZODIAC OF.] The only attempt at a measure which we have remaining is one of the diameter of the sun, the meaning of which is obscure; but if what Delambre mentions (without citing his authority) be true, that they measured time by the distance run by a horse, as well as by the clepsydra, we need not be surprised that Ptolemy found no assistance from their ancient observations. The story of Thales teaching the Egyptians how to find the height of the pyramids by the shadow, and that in Herodotus, of his being told by them that the sun