Part 22

“324. For a farther illustration, THUCYDIDES relates, that a solar Eclipse happened on a Summer’s day in the afternoon, in the first year of the _Peloponnesian_ war, so great that the Stars appeared. _Rhodius_ was victor in the _Olympic_ games the fourth year of the said war, being also the fourth of the 87th _Olympiad_, on the 428th year before CHRIST. So that the Eclipse must have happened in the 431st year before CHRIST; and by computation it appears, that on the 3d of _August_ there was a signal Eclipse which would have past over _Athens_, central about 6 in the evening, but which our present Tables bring no farther than the antient _Syrtes_ on the _African_ coast, above 400 miles from _Athens_; which suffering in that case but 9 Digits, could by no means exhibit the remarkable darkness recited by this historian; the center therefore seems to have past _Athens_ about 6 in the evening, and probably might go down about _Jerusalem_, or near it, contrary to the construction of the present Tables. I have only obviated these things by way of caution to the present Astronomers, in re-computing antient Eclipses; and refer them to examine the Eclipse of _Nicias_, so fatal to the _Athenian_ fleet[71]; that which overthrew the _Macedonian_ Army[72] _&c._” So far Mr. SMITH.

[Sidenote: The number of Eclipses.]

325. In any year, the number of Eclipses of both Luminaries cannot be less than two, nor more than seven; the most usual number is four, and it is very rare to have more than six. For the Sun passes by both the Nodes but once a year, unless he passes by one of them in the beginning of the year; and if he does, he will pass by the same Node again a little before the year be finished; because, as these points move 19 degrees backward every year, the Sun will come to either of them 173 days after the other § 319. And when either Node is within 17 degrees of the Sun at the time of New Moon, the Sun will be eclipsed. At the subsequent opposition the Moon will be eclipsed in the other Node; and come round to the next conjunction again ere the former Node be 17 degrees past the Sun, and will therefore eclipse him again. When three Eclipses fall about either Node, the like number generally falls about the opposite; as the Sun comes to it in 173 days afterward: and six Lunations contain but four days more. Thus, there may be two Eclipses of the Sun and one of the Moon about each of her Nodes. But when the Moon changes in either of the Nodes, she cannot be near enough the other Node at the next Full to be eclipsed; and in six lunar months afterward she will change near the other Node: in these cases there can be but two Eclipses in a year, and they are both of the Sun.

[Sidenote: Two periods of Eclipses.]

326. A longer, and consequently more exact period than the above-mentioned § 320, for comparing and examining Eclipses which happen at long intervals of time, is 57 _Julian_ years 324 days 21 hours 41 minutes and 35 seconds; in which time there are just 716 mean Lunations, and the Sun is again within 5 minutes of the same Node as before. But a still better period is 557 years 21 days 18 hours 30 minutes 12 seconds; in which time there are 6890 mean Lunations; and the Sun and Node meet again so nearly as to be but 11 seconds distant.

[Sidenote: An account of the following catalogue of Eclipses.]

327. We shall subjoin a catalogue of Eclipses recorded in history, from 721 years before CHRIST to _A. D._ 1485; of computed Eclipses from 1485 to 1700; and of all the Eclipses visible in _Europe_ from 1700 to 1800. From the beginning of the catalogue to _A.D._ 1485 the Eclipses are taken from STRUYK’s _Introduction to universal Geography_, as that indefatigable author has, with much labour, collected them from _Ptolemy_, _Thucydides_, _Plutarch_, _Calvisius_, _Xenophon_, _Diodorus Siculus_, _Justin_, _Polybius_, _Titus Livius_, _Cicero_, _Lucanus_, _Theophanes_, _Dion Cassius_, and many others. From 1485 to 1700 the Eclipses are taken from _Ricciolus_’s _Almagest_: and from 1700 to 1800 from _L’art de verifier les Dates_[73]. Those from _Struyk_ have all the places mentioned where they were observed: Those from the _French_ authors, _viz._ the religious _Benedictines_ of the Congregation of St. _Maur_, are fitted to the Meridian of _Paris_: And concerning those from _Ricciolus_, that author gives the following account.

Because it is of great use for fixing the Cycles or Revolutions of Eclipses, to have at hand, without the trouble of calculation, a list of successive Eclipses for many years, computed by authors of _Ephemerides_, although from Tables not perfect in all respects, I shall for the benefit of Astronomers give a summary collection of such. The authors I extract from are, an anonymous one who published _Ephemerides_ from 1484 to 1506 inclusive; _Jacobus Pflaumen_ and _Jo. Stæflerinus_, to the Meridian of _Ulm_, from 1507 to 1534: _Lucas Gauricus_, to the Latitude of 45 degrees, from 1534 to 1551: _Peter Appian_, to the Meridian of _Leysing_, from 1538 to 1578: _Jo. Stæflerus_ to the Meridian of _Tubing_, from 1543 to 1554: _Petrus Pitatus_, to the Meridian of _Venice_ from 1544 to 1556: _Georgius-Joachimus Rheticus_, for the year 1551: _Nicholaus Simus_, to the Meridian of _Bologna_, from 1552 to 1568: _Michael Mæstlin_, to the Meridian of _Tubing_, from 1557 to 1590: _Jo. Stadius_, to the Meridian of _Antwerp_, from 1554 to 1574: _Jo. Antoninus Maginus_, to the Meridian of _Venice_, from 1581 to 1630: _David Origan_, to the Meridian of _Franckfort_ on the _Oder_, from 1595 to 1664: _Andrew Argol_, to the Meridian of _Rome_, from 1630 to 1700: _Franciscus Montebrunus_, to the Meridian of _Bologna_, from 1461 to 1660: Among which, _Stadius_, _Mæstlin_, and _Maginus_, used the _Prutenic_ Tables; _Origan_ the _Prutenic_ and _Tychonic_; _Montebrunus_ the _Lansbergian_, as likewise those of _Duret_. Almost all the rest the _Alphonsine_.

But, that the places may readily be known for which these Eclipses were computed, and from what Tables, consult the following list, in which the years _inclusive_ are also set down.

From 1485 to 1506 The place and author unknown. 1507 1553 _Ulm_ in _Suabia_, from the _Alphonsine_. 1554 1576 _Antwerp_, from the _Prutenic_. 1577 1585 _Tubing_, from the _Prutenic_. 1586 1594 _Venice_, from the _Prutenic_. 1595 1600 _Franckfort_ on _Oder_, from the _Prutenic_. 1601 1640 _Franckfort_ on _Oder_, from the _Tychonic_. 1641 1660 _Bologna_, from the _Lansbergian_. 1661 1700 _Rome_, from the _Tychonic_.

So far RICCIOLUS.

_N. B._ The Eclipses marked with an Asterisk are not in RICCIOLUS’s catalogue; but are supplied from _L’art de verifier les Dates_.

From the beginning of the catalogue to _A. D._ 1700, the time is reckoned from the noon of the day mentioned to the noon of the following day; but from 1700 to 1800 the time is set down according to our common way of reckoning. Those marked _Pekin_ and _Canton_ are Eclipses from the _Chinese_ chronology according to STRUYK; and throughout the Table this mark ☉ signifies _Sun_, and this 🌑︎ _Moon_.

STRUYK’s Catalogue of ECLIPSES.