superseding of the Egyptian annals was brought about by his influence. It was forgotten, however, that of all things chronology is the least suited to be an object of inspiration; and that, though men may be wholly indifferent to truth for its own sake, and consider it not improper to wrest it unscrupulously to what they may suppose to be a just purpose, yet that it will vindicate itself at last. It is impossible to succeed completely in perverting the history of a nation which has left numerous enduring records. Egypt offers us testimonials reaching over five thousand years. As Bunsen remarks, from the known portion of the curve of history we may determine the whole. The Egyptians, old as they are, belong to the middle ages of mankind, for there is a period antecedent to monumental history, or indeed, to history of any kind, during which language and mythology are formed, for these must exist prior to all political institutions, all art, all science. Even at the first moment that we gain a glimpse of the state of Egypt she had attained a high intellectual condition, as is proved by the fact that her system of hieroglyphics was perfected before the fourth dynasty. It continued unchanged until the time of Psammetichus. A stationary condition of language and writing for thousands of years necessarily implies a long and very remote period of active improvement and advance. It was doubtless such a general consideration, rather than a positive knowledge of the fact, which led the Greeks to assert that the introduction of geometry into Egypt must be attributed to kings before the times of Menes. Not alone do her artificial monuments attest for that country an extreme antiquity; she is herself her own witness; for, though the Nile raises its bed only four feet in a thousand years, all the alluvial portion of Egypt has been deposited from the waters of that river. natural register thus re-enforces the written records, and both together compose a body of evidence not to be gainsaid. Thus the depth of muddy silt accumulated round the pedestals of monuments is an irreproachable index of their age. In the eminent position he occupied, Eusebius might succeed in perverting the received bookchronology; but he had no power to make the endless

A

trade-wind that sweeps over the tropical Pacific blow a day more or a day less; none to change the weight of water precipitated from it by the African mountains; none to arrest the annual mass of mud brought down by the river. It is by collating such different orders of evidence together-the natural and the monumental, the latter gaining strength every year from the cultivation of hieroglyphic studies-that we begin to discern the true Egyptian chronology, and to put confidence in the fragments that remain of Eratosthenes and Manetho.

At the time of which we are speaking-the time of Eratosthenes-general ideas had been attained to respecting the doctrine of the sphere, its poles, axis, the equator, arctic and antarctic circles, equinoctial points, Astronomy of solstices, colures, horizon, etc. No one com- Eratosthenes. petent to form an opinion any longer entertained a doubt respecting the globular form of the earth, the arguments adduced in support of that fact being such as are still popularly resorted to the different positions of the horizon at different places, the changes in elevation of the pole, the phenomena of eclipses, and the gradual disappearance of ships as they sail from us. As to eclipses, once looked upon with superstitious awe, their true causes had not only been assigned, but their periodicities so well ascertained that predictions of their occurrence could be made. The Babylonians had thus long known that after a cycle of 223 lunations the eclipses of the moon return. The mechanism of the phases of that satellite Attempts of was clearly understood. Indeed, Aristarchus Aristarchus of Samos attempted to ascertain the distance of distance of the the sun from the earth on the principle of sun. observing the moon when she is dichotomized, a method quite significant of the knowledge of the time, though in practice untrustworthy; Aristarchus thus finding that the sun's distance is eighteen times that of the moon, whereas it is in reality 400. In like manner, in a general way, pretty clear notions were entertained of the climatic distribution of heat upon the earth, exaggerated, however, in this respect, that the torrid zone was believed to be too hot for human life; and the frigid too cold. Observations, as good as could be made by simple instruments,

to find the

had not only demonstrated in a general manner the progressions, retrogradations and stations of the planets, but attempts had been made to account for, or rather to represent them, by the aid of epicycles.

It was thus in Alexandria, under the Ptolemies, that modern astronomy arose. Ptolemy Soter, the founder of this line of kings, was not only a patron of science, but likewise an author. He composed a history of the campaigns of Alexander. Under him the collection of the Biography of library was commenced, probably soon after the the Ptolemies. defeat of Antigonus at the battle of Ipsus, B.C. 301. The museum is due to his son Ptolemy Philadelphus, who not only patronized learning in his own dominions, but likewise endeavoured to extend the boundaries of human knowledge in other quarters. Thus he sent an expedition under his admiral Timosthenes as far as Madagascar. Of the succeeding Ptolemies, Euergetes and Philopator were both very able men, though the later was a bad one; he murdered his father, and perpetrated many horrors in Alexandria. Epiphanes, succeeding his father when only five years old, was placed by his guardians under the protection of Rome, thus furnishing to the ambitious republic a pretence for interfering in the affairs of Egypt. The same policy was continued during the reign of his son Philometor, who, upon the whole, was an able and good king. Even Physcon, who succeeded in B.C. 146, and who is described as sensual, corpulent, and cruel-cruel, for he cut off the head, hands, and feet of his son, and sent them to Cleopatra his wife-could not resist the inspirations to which the policy of his ancestors, continued for nearly two centuries, had given birth, but was an effective promoter of literature and the arts, and himself the author of an historical work. A like inclination was displayed by his successors, Lathyrus and Auletes, the name of the latter indicating his proficiency in music. The surnames under which all these Ptolemies pass were nicknames, or titles of derision imposed upon them by their giddy and satirical Alexandrian subjects. The political state of Alexandria was significantly said to be a tyranny tempered by ridicule. The dynasty ended in the person of the celebrated Cleopatra, who, after the

battle of Actium, caused herself, as is related in the legends, to be bitten by an asp. She took poison that she might not fall captive to Octavianus, and be led in his triumph through the streets of Rome.

If we possessed a complete and unbiassed history of these Greek kings, it would doubtless uphold their title to be regarded as the most illustrious of all ancient sovereigns. Even after their political power had passed into the hands of the Romans-a nation who had no regard to truth and to right-and philosophy, in its old age, had become extinguished or eclipsed by the faith of the later Cæsars, enforced by an unscrupulous use of their power, so strong was the vitality of the intellectual germ they had fostered, that, though compelled to lie dormant for centuries, it shot up vigorously on the first occasion that favouring circumstances allowed.

They pa

as science.

This Egyptian dynasty extended its protection and patronage to literature as well as to science. Thus Philadelphus did not consider it beneath him to count among his personal friends the poet Callimachus, who had written a treatise on birds, and honour- tronize literaably maintained himself by keeping a school in ture as well Alexandria. The court of that sovereign was, moreover, adorned by a constellation of seven poets, to which the gay Alexandrians gave the nickname of the Pleiades. They are said to have been Lycophron, Theocritus, Callimachus, Aratus, Apollonius Rhodius, Nicander, and Homer the son of Macro. Among them may be distinguished Lycophron, whose work, entitled Cassandra, still remains; and Theocritus, whose exquisite bucolics prove how sweet a poet he was.

To return to the scientific movement. The school of Euclid was worthily represented in the time of Euergetes. by Apollonius Pergæus, forty years later than The writings Archimedes. He excelled both in the mathe- of Apollonius. matical and physical department. His chief work was a treatise on Conic Sections. It is said that he was the first to introduce the words ellipse and hyperbola. So late as the eleventh century his complete works were extant in Arabic. Modern geometers describe him as handling his subjects with less power than his great predecessor

Archimedes, but nevertheless displaying extreme precision and beauty in his methods. His fifth book, on Maxima and Minima, is to be regarded as one of the highest efforts of Greek geometry. As an example of his physical inquiries may be mentioned his invention of a clock.

The writings

Fifty years after Apollonius, B.C. 160-125, we meet with the great astronomer Hipparchus. He does not appear to have made observations himself in Alexandria, but he uses those of Aristyllus and Timochares of that place. Indeed, his great discovery of the precession of the equinoxes was essentially founded on the discussion of the Alexandrian observations on Spica Virginis made by Timochares. In pure mathematics he gave methods for solving all triangles plane and spherical: he also constructed a table of Hippar- of chords. In astronomy, besides his capital chus. discovery of the precession of the equinoxes just mentioned, he also determined the first inequality of the moon, the equation of the centre, and all but anticipated Ptolemy in the discovery of the evection. To him also. must be attributed the establishment of the theory of epicycles and eccentrics, a geometrical conception for the purpose of resolving the apparent motions of the heavenly bodies, on the principle of circular movement. In the case of the sun and moon, Hipparchus succeeded in epicycles and the application of that theory, and indicated eccentrics. that it might be adapted to the planets. Though never intended as a representation of the actual motions of the heavenly bodies, it maintained its ground until the era of Kepler and Newton, when the heliocentric doctrine, and that of elliptic motions, were incontestably established. Even Newton himself, in the 37th proposition of the third book of the "Principia," availed himself of its aid. Hipparchus also undertook to make a register of the stars by the method of alineations—that is, by indicating those which were in the same apparent straight line. The number of stars catalogued by him was 1,080. If he thus depicted the aspect of the sky for his times, he also endeavoured to do the same for the surface of the earth by marking the position of towns and other places by lines of latitude and longitude.

The theory of

Subsequently to Hipparchus, we find the astronomers Geminus and Cleomedes; their fame, however, is totally