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history of the world. Among the eclipses of this character we may mention the following :—The one mentioned by Herodotus, already referred to. This eclipse is alluded to by several other ancient writers, who flourished subsequently to Herodotus. This author does not state when the eclipse occurred; but Cicero and Pliny assert that it happened in the 4th year of the 48th Olympiad, which corresponds to the year 585 B.C. This eclipse has given rise to a good deal of discussion among calculators. Riccioli and Newton, and various other modern writers, adopt the date mentioned above. Scaliger, however, found, by actual calculation, that it happened on the 1st of October, 583 B.C. Archbishop Usher placed it in the year 601 B.C.; and Bayer and Costard think that Herodotus refers to a total solar eclipse which it was formerly thought happened in the year 603 B.C. But any solution of the question, based on actual computation by means of the solar and lunar tables, previously to the publication of the recent accurate lunar tables by M. Hansen, and the corrections of other theories by Peirce and Longstreth; and the solar tables of Hansen and Olufsen were necessarily imperfect, and could only give approximate results. Baily's solution, in 1811, was considered for many years, however, as having decided the question.' He began by skillfully criticising the original passage in which the Grecian historian alludes to the eclipse of Thales, and he concluded that it could not have happened earlier than 629 B.C., nor later than 595 B.C. Out of seventy eclipses which happened in that period, he found only one that was total in the peninsula of Asia Minor, and that he fixed on the 30th of September, 610 B.C.* It has more recently been discovered, however, that the secular motion of the moon's node, used in the calculations, was erroneous by more than a minute and a half, and Professor Airy has shown that the eclipse occurred 584 B.C., May the 28th, thus confirming the statements of Cicero and Pliny. Hence we see how the secular variations of the elements of the moon's orbit are connected with our knowledge of important ancient celestial phenomena.

* Phil. Trans., 1811, p. 220, et seq.

Herodotus also mentions another eclipse, * when Cyaxares was at war with the Lydians, “when the engagement, which happened in the day, was suddenly interrupted by nocturnal darkness.” The father of history also mentions a solar eclipse, which happened when Xerxes was advancing with his army from Sardis to Abydos. “At the moment of their departure, the sun, which before gave his full light, in a bright, unclouded atmosphere, withdrew his beams, and the darkest night succeeded.”+ The date of this last eclipse has been referred to 480, B.C. Professor Airy thinks, however, that it was not a solar eclipse, but a total eclipse of the moon, which, it appears, took place March 19th, 478 B.C.

Xenophon mentions an eclipse of the sun, which led to the capture of Larrisa by the Persians. Dwing the retreat, which was conducted by Xenophion, the Greeks passed “a large deserted city, called Larissa, formerly inhabited by the Medes. Its walls were twenty-five feet thick, and a hundred feet high; its circumference two parasangs; it was built of burnt brick, on a foundation of stone, twenty feet high. When the Persians conquered the Medes, the Persian king besieged this city, but was unable to capture it till a cloud hid the sun wholly from view, when the inhabitants withdrew in great fear, and the city was captured.” The Greeks, after passing Larissa, reached another deserted city, called Mespila. Layard, in his researches in Assyria, identified Larissa with the modern Nimroud ;s and Mespila with the ruins opposite the modern Mosul. | Professor Airy has shown that this eclipse happened May 19th, 556 B.C.

It is not a little curious, how frequently eclipses are associated with important undertakings among ancient nations. Thus a total eclipse of the sun, supposed to have taken place August 31, 430 B.C.,? seriously threatened the success of the expedition of the Athenians under Pericles. He manned a hundred and fifty ships, and was preparing to set sail. “The Athenians conceived good hopes of success, and the enemy

* Book I., sect. 93.1 Book VII, sect. 37. I Grant's Hist. Phys. Ast., p. 363. $ Nineveh and its Remains, vol. I., p. 27. [lbid, vol. II., p. 196 and 218.

Ilind's Solar System, p. 102.

no less dreaded so great an armament. The whole fleet was in readiness, and Pericles on board of his own galley, when there happened an eclipse of the sun. This sudden darkness was looked upon as an unfavorable omen, and threw them into the greatest consternation. Pericles, observing that the pilot was much astonished and perplexed, took his cloak, and, having covered his eyes with it, asked him, if he found anything so terrible in that, or considered it a sad presage. Upon his answering in the negative, he said :

Where is the difference, then, between this and the other except that something bigger than my cloak causes the eclipse?'”* Although it is evident that Pericles had some knowledge of the cause of the eclipse, it does not appear that it had been predicted.

Among the solar eclipses of antiquity, that known as the eclipse of Agathocles has given rise to as much trouble as almost any other. We are informed by Diodorus Siculus, that the voyage to Africa, from Syracuse occupied six days, and that, on the second day, an eclipse occurred, during which the darkness was so complete, that the stars became visible in all directions. The eclipse was, therefore, total. Neither the date nor the locality was open to much doubt, or uncertainty, and the phenomena, therefore, seemed to Mr. Francis Baily to afford a favorable opportunity for checking the solar and lunar tables, instead of using them to settle the date and limits of the eclipse. He found an irreconcilable difference of 180 geographical miles between the tables and the historical statement in regard to the most southerly position that can be assigned to the fleet of Agathocles, and the limit of the total phase. “To obviate this difference,” says Hind,+ “it is only necessary to stippose an error of about three minutes of arc in the computed distance of the centres of the sun and moon at conjunction-a very inconsiderable correction for a date anterior to the epoch of the tables by more than twenty-one centuries." Professor Airy has been more successful, by founding his calculations on improved lunar tables; and he has shown

* Plutarch's Lives-Pericles, p. 126; Langhan's Translat'on.

Solar System, p. 102.

that the limits of the zone of totality were such, that Agathocles might have been involved in the moon's shadow, during his passage.

According to Philastratus, * the death of the Roman emperor, Domitian, was previously announced by a celestial phenomenon, which appears to have been an eclipse of the sun; and we mention it here because the account of it probably contains the earliest record of which we have any account, of a phenomenon accompanying total solar eclipses, that has of late years attracted much attention. We refer to the luminous ring, or corona, surrounding the moon during totality. “In the heavens,” he says, “there appeared a prodigy of this nature; a certain corona, resembling the Iris, surrounded the orb of the sun, and obscured his light.” This eclipse occurred in the year 95 A. D. Many other total solar eclipses are recorded to have happened during years intervening from 237 to 1113 of our era, but they require no further mention here.

Sir Edmund Halley communicated to the Royal Society a paper on the total eclipse of the sun, which happened at London, on the 3d of May, 1715, † and in it he alludes to the fact, without indicating very clearly whence he derived his information, that there had not occurred before then another total eclipse of the same body, visible in that city, since the 20th of March, 1140 A. D.—a period of 575 years -so infrequently are total eclipses of the sun visible from any particular locality on the earth. A notice of the lastmentioned eclipse occurs, however, in the section of the “Saxon Chronicle” which relates to the year 1140: “In the Lent, the sun and the day darkened about the noontide of the day, when men were eating; and they lighted candles to eat by. That was the thirteenth day before the calends of April. Men were very much struck with wonder.”

On the 17th of June, 1433, a remarkable total solar eclipse happened, which was visible in Scotland, and the time of its occurrence was long remembered by the people of that

* Life of Apollonius. Phil. Trans., 1715, p. 245, et seq.

| Saxon Chronicle, p. 371 of Ingram's translation.

country as the black hour. According to Maclaurin, the celebrated mathematician, a manuscript account of it is preserved in the library of the university of Edinburgh. It is there stated that it took place about three o'clock in the afternoon, and that the darkness was so complete that nothing was visible—a statement that is evidently exaggerated, since the absence of the sun in the night does not produce such an effect. The eclipse, however, was one of a very unusual kind, since Maclaurin found, by calculation, that, at the time of its occurrence, the sun was only 2o from his apogee, and the moon not more than 13° from perigee.

In the year 1598, there occurred a total eclipse of the sun, which was visible in the British Isles. The moon's shadow passed over the border countries of England and Scotland, and the day of the eclipse was long remembered, in both countries, as " black Saturday.” In 1652, there was another total eclipse of the sun visible in Great Britain and Ireland. Dr. Wyberd observed it at Carrickfergus, in the north of Ireland, t and in Scotland, the day of its occurrence, gave rise, among the common people, to the expression “mirk Monday,” and it is even still used in some parts of that country, although the eclipse was long ago forgotten.

On the 24th of September, 1699, there occurred a total eclipse in the north of Europe, and a correspondent of the Royal Society, writing from Leipsic, where it was almost total, says that when ten digits were covered," the sky,

, being otherwise very clear, began to appear of a more livid, or wan, complexion, and more sad than it usually looks, with a clear sky, when the sun is set, or below the horizon." He adds, that "the cocks, which had before crowed very frequently, left off crowing, and went to roost, and they did not renew it till, by the recovery of the sun's light, they had recovered their former gaity and mirth.”+ Souville, in his account of the eclipse of 1715, mentions the same thing.

Until the year 1706, solar eclipses seem to have attracted no further attention than the observation of their ordinary

* Phil. Trans., 1737, p. 134.
† Wing's Astronomia Britannica, p. 355. + Phil. Trans., 1700, p. 624.
VOL. XX.NO. XXXIX.

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