462 



COPERNICUS 



COPLEY 



life was written by Gassendi ; more recently by 

 Von Hipler (1873), 'and Polkovski (Warsaw, 1873). 

 By far the most complete account of Copernicus's 

 life and labours is, however, the great biography 

 by Dr Prowe (2 vols. Berlin, 1883 ; volume of docu- 

 ments, 1884 ). Copernicus's family name of Kopper- 

 nigk is derived from a village so called in Silesia, 

 and was Latinised by himself as Coppernicus, and 

 indeed by him generally so spelt. 



THE COPERNICAN SYSTEM is that which repre- 

 sents the sun to be at rest in the centre of the 

 universe, and the earth and planets to move round 

 it as a centre. It got its name from Coper- 

 nicus, who (although some vague general notion 

 of the system seems to be due to Pythagoras ) first 

 distinctly drew the attention of philosophers to it, 

 and devoted his life to its demonstration. For the 

 rest, the glory of developing on the lines he broadly 

 laid down, belongs to Kepler, Galileo, and others, 

 and to Newton, who finally marked out the form 

 of modern theoretical astronomy. Many who 

 reverence the name of Copernicus in connection 

 with this system, would be surprised to find, on 

 perusing his work, how much of error, unsound 

 reasoning, and happy conjecture combined to 

 secure for him in all times the association of the 

 system with his name ; yet, with all its faults, that 

 work marks one of the greatest steps ever taken in 

 science. 



Entitled De Revolutionibus Orbium, and dedi- 

 cated to Pope Paul III., it consists of six books. 

 The first contains the following propositions: 

 1. That the universe is spherical. This is estab- 

 lished by such arguments as that the sphere 

 is the most perfect figure, &c. 2. That the earth 

 is spherical, which flows from the same kind of 

 considerations. 3. That the earth and sea make 

 one globe. 4. That the motions of all the heavenly 

 bodies must be uniform and circular, or com- 

 pounded of uniform and circular motions. Here, 

 again, we meet with singular reasons. A simple 

 body must move circularly, and nothing but cir- 

 cular motion could give periodicity to phenomena. 

 5. That, supposing the distance of the stars to be 

 immense, there is no reason why the earth should 

 not have a motion round its axis as well as a 

 motion in its orbit. 6. That the sphere of the 

 stars is immensely distant. The proof is fanciful, 

 and shows he had no notion of a universe of stars 

 pervading space. 7 and 8. The ancients were 

 wrong in placing the earth at the centre of the 

 universe. The arguments under this head are as 

 fanciful as those which they were designed to 

 refute. The falling of a body to the earth he 

 deduces from the assumption, that it is only given 

 to wholes to move circularly, while it is of the 

 nature of parts, separated from their wholes, to 

 move in right lines. That there must be a centrum 

 mundi, an entity unknown to modern science, is 

 admitted, the question being as to its position. 9. 

 It is possible for the earth to have several motions. 

 10. He establishes the order of the planets, and 

 draws a diagram of the system much as it is now 

 represented. Following the old systems, such as 

 the Ptolemaic, he lays down a sphere for the fixed 

 stars. It is clear, also, that he had no idea of 

 the motions of the planets other than that they 

 were such as would be caused by their being fixed 

 in immense crystal spheres revolving round the 

 sun. 



The sum of Copernicus's astronomical achieve- 

 ments is, mainly, the shifting of the centre of the 

 solar system from the earth to the sun, and the 

 consequent explanation of the alternation of day 

 and night by the earth's rotation round itself, and 

 of the vicissitude of the seasons by the earth's 

 revolution round the sun. This complete trans- 

 formation in astronomy was due in the first 



instance to the sense of order in Copernicus's. 

 own mind, which, ever more clearly, protested 

 against the inverse conception of a much smaller 

 body at the centre, and a far greater at the cir- 

 cumference, and all the repugnant notions regard- 

 ing the movements of the planets which such a 

 conception involved. Discriminating motion as an 

 attribute of matter, and space as the scene but 

 not the subject of motion, Copernicus explained 

 how the celestial sphere was but a limitation of 

 space, and its movement only apparent ; and 

 how the 'backward loopings' of the paths pur- 

 sued by the planets were only the perspective 

 result of their real movements in conjunction 

 with the real movements of the earth. Such 

 was the comprehensive scheme of astronomy con- 

 ceived by Copernicus ; but it was impossible for 

 him, with the instruments and ascertained fact* 

 then at his disposal, to master all the details. 

 Instead of grasping the idea of elliptic orbits, he 

 still abode by that of uniform circular motion, 

 and had therefore to retain the ' epicycles ' to- 

 account for 'irregularities,' though he reduced 

 this apparatus of checks and balances to the 

 number of thirty-four. It was reserved for Kepler 

 to dispense with the epicycles (see PTOLEMAIC 

 SYSTEM, ASTRONOMY, KEPLER). Catholic church- 

 men received Copernicus's work with much favour ; 

 the only theological objections came from the 

 Protestants. Luther denounced Copernicus as an 

 arrogant fool who wrote in defiance of Scrip- 

 ture, and Melanchthon urged the suppression of 

 such mischievous doctrines by the secular power. 

 The conduct of the De Revolutionibus through the 

 press having been delegated by Copernicus's friend, 

 George Joachim von Lauchen (Rheticus) to Osi- 

 ander (q.v.), the latter, by way of conciliating 

 existing prejudices, foisted on the work a preface 

 (Prcefatiuncula} quite foreign from Copernicus's 

 intentions, in which the doctrine of the earth's 

 rotation is represented as a mere hypothesis, which 

 has been attributed wrongly to Copernicus himself. 



Copiapo, capital of the Chilian department of 

 Atacama (q.v.). 



Copland, JAMES, physician, Avas born at Deer- 

 ness, in the Orkneys, in 1791. He graduated M.D. 

 at Edinburgh in 1815, and settled to practice in 

 London in 1820, where he soon began to make his 

 name known by his papers in the medical journals 

 on yellow-fever, hydrophobia, cholera, and the like. 

 His largest work was the Dictionary of Practical 

 Medicine (3 vols. 1832), a monument of enormous 

 industry ; others were on palsy and apoplexy ( 1850), 

 and on consumption ( 1861 ). He died 12th July 

 1870. 



Copley, JOHN SINGLETON, R.A., portrait and 

 historical painter, was born 3d July 1737, at 

 Boston, U.S. His parents, both of English extrac- 

 tion, had emigrated from Ireland in the previous 

 year. It has usually been asserted that Copley 

 was a self-taught artist ; but Mr W. H. Whitmore 

 of Boston has shown that he was instructed by his 

 stepfather, Peter Pelham, the portrait-painter and 

 engraver, and probably also by John Smibert. At 

 the age of sixteen he was executing portraits of 

 considerable merit ; and in 1755 Washington sat 

 to him. In 1766 and 1767 he sent over works for 

 exhibition in the rooms of the Society of Incorporated 

 Artists ; and in June 1774 he left for Europe. In 

 London he was well received by Reynolds, West, 

 and Strange, and he was commissioned to paint the 

 king and queen for Governor Wentvvorth. Passing 

 to the Continent in August, he studied in Italy, 

 returning to London in the end of 1776. His first 

 important subject-picture was the ' Youth rescued 

 from a Shark,' presented by the artist to Christ's 

 Hospital School ; which was followed by ' The 



