ASTRONOMY. 



Aejhr (died about ISSn. pabliahed almanac* for fifty year* ; wrote 

 00 the actrolabe, to. 



JfiHMftr (died 1MJ). wrote M dock* and dial*. 



Prnaularim* idled 1 i8). wrote aa the heavenly motions. 



la 1548. ATM*, wbo died in 1568. gmr, a very correct meHure of a 

 of UM meridian, from uch inwAcient obaervaUon*, that, as 

 remarks, U oomctea* mu.t have been aeddentaL 



Phenomena observed to the clan of the 16th century : 



10SO. A total ealipw of the ran, oWnre.1 in Norway. 



1106. A great comet appeared. IU Uil was compared to a beam 

 of Br extending along the heaven*. 



1140. OooumooTof total eoUpw of the can which WM viable in 

 London. Tab eclipee is mentioned in the Baxon Chroniole and in 

 the writing, of William of Malmesbury. 



14S4. Apparition of a great cornet in the heareni, accompanied by 

 a Uil 100 in length. 



1402. Two great comet* appeared in the heaven* in the course of 

 this rear. 



1483. Occurrence of a total eclipse of the sun which waa viable in 

 Scotland. 



14(0. Apparition of a great comet which Rpread universal terror 

 throughout Europe. This U known to have been one of the appa- 

 rition* of Halley'a comet. 



1448. A great comet viaible : observed in Europe and China. 



1472. A great comet observed both in Europe and China. In one 

 day it described an arc of 40*. 



Copmirtu, born 1473, died 154S. Applied himself to astronomy 

 from 1500. In 1530, be had finished his tables of the planets, and his 

 work ' On the Revolutions of the Heavenly Bodies,' containing an 

 explanation of (he COPKRXICA* SYSTKJI, which, it is almost unneces- 

 sary to say, waa a revival of the opinions of the Pythagorean school on 

 the motion of the earth. It was published in 1543, and its author 

 died immediately afterwards. Copernicus improved the lunar tables, 

 and gave, to a considerable extent, on explanation of celestial jihi'iio- 

 mena upon his own system. His book is a mixture of his own original 

 and sagacious notions and of the old philosophy ; and he was far from 

 being able to answer the mechanical objections of his time. What 

 might have struck so bold a thinker, hod he lived to face opposition, 

 cannot be told, but as the history stands, we shall come to the time of 

 Galileo before we find all objections satisfactorily answered. 



From this period, at which the preservation of printed works com- 

 mences, our limits will not permit our giving more than the names of 

 many astronomers. The following is the list of those who are worth 

 mention between Copernicus and the death of Tycho Brahe'. The 

 history of this period has been elucidated chiefly by Professor De Morgan. 

 The dates are generally those of death, but where that is not known, 

 the date in bracket* is that of the publication of some work. 



The Copernioan theory had its advocate*, but was not yet adopted by 

 many. Algebra had been introduced into most parts of Europe, but 

 was not yet in a state to furnish much assistance in trigonometry. 

 Logarithm* were not yet invented, nor do we find the t n/r im( fixed 

 in the meridian, the ttkmpt, or the ;vi<//m dock. The first 

 uisui'usr, who made any important additions to the phenomena 

 heaven* M received from the Araks, was Tycho limbo, to whom we 

 now oome. 



Tyeko ItraJii, bom 1546, began to study astronomy 1560 ; commenced 

 bis observations at Huena, an island, in the Baltic, near Copenhagen, 

 1583 ; was driven from thence, 1697 ; died 1601. He made a catalogue 

 of the fixed stars, more accurate than any which preceded : gu 

 first table of refractions : discovered the rariutimt and antttnl equation 

 (which see) of the moon, the variation of the motion of her nodes, and 

 of the inclination of her orbit. What was essentially as great a service 

 as any of the preceding, he discarded the tnpidation of the precession, 

 already mentioned, which had more or leas infected all tables up 

 time ; he also ascertained that comets (those of hi* day, of course) 

 were further removed from the earth than the moon ; in fact, that they 

 had no parallax which his instruments could discover, thus refuting 

 the notion that they were atmospheric bodies. He greatly inii 

 and extended the instrument* in use a* well as all the methods of 

 observation. 



Tycho Brahd did not admit the Copernican theory ; but substituted 

 for it one of his own, usually known by the name of the Tyrhonic 

 ii/itrm. This consisted in supposing the sun to move round the earth, 

 but all the other planet* to move round the sun, being also carried 

 with it round the earth. This system explain* all the appearances a* 

 well as that of Copernicus ; and we must say (though it is always 

 usual to reproach Tycho for refusing to admit the simple system of 

 :itmx) that liy this means the tAr* unanswerable arguments 

 against the Copernioan system were iivi<inl. In fact, there is 

 bvit the aberration of tight (a comparatively recent discovery), which is 

 detnonstrably conclusive in favour of the annual motion of the earth. 

 [AHKHKATIOX; MOTION (Arp.uiKxx).] The system of Tycho is said 

 to have been promulgated by some of the ancients, at loast with regard 

 to the inferior planets. 



The reformation (as it was called) of the calendar took place in 1582, 

 under Pope Gregory XIII. As the views of those who made the 

 change wore rather theological than a6troin<]iiic,il, we shall only here 

 mention the fact and the disputes it gave rise to; referrii 

 further information to CALENDAR. 



From the time of the death of Tycho Brand, to that of Js < 

 which forms the next great epoch in the history of astronomy, we can 

 only dwell generally on a few leading discoveries. To 

 reader to search further, we give a table of all the names between the 

 deaths of Tycho Broh and Newton, which Delambre has thought 

 worthy of any mention, with some few additions. The name 

 tioned from 1581 to 1727, which are not in this list, \\ill ! f.miid in 

 the next. The year of death is given <>p]*isito to each name ; or win re 

 that is not known, the year of some pulili^aion is given in bracket*. 

 The dates are principally from Weidler, and several from Delambre, 



