CHAPTER V.

THE RECEPTION OF THE COPPERNICAN THEORY AND THE PROGRESS OF OBSERVATION (FROM ABOUT 1543 A.D. TO ABOUT 1601 A.D.), §§ 93-112 125-144

§§ 93-4. The first reception of the _De Revolutionibus_: _Reinhold_: the _Prussian Tables_ 125

§ 95. Coppernicanism in England: _Field_, _Recorde_, _Digges_ 127

§ 96. Difficulties in the Coppernican system: the need for progress in dynamics and for fresh observations 127

§§ 97-8. The Cassel Observatory: the Landgrave _William IV._, _Rothmann_, and _Bürgi_: the star catalogue: Bürgi’s invention of the pendulum clock 128

§ 99. =Tycho Brahe=: his early life 130

§ 100. The new star of 1572: travels in Germany 131

§§ 101-2. His establishment in Hveen: Uraniborg and Stjerneborg: life and work in Hveen 132

§ 103. The comet of 1577, and others 135

§ 104. Books on the new star and on the comet of 1577 136

§ 105. Tycho’s system of the world: quarrel with _Reymers Bär_ 136

§ 106. Last years at Hveen: breach with the King 138

§ 107. Publication of the _Astronomiae Instauratae Mechanica_ and of the star catalogue: invitation from the Emperor 139

§ 108. Life at Benatek: co-operation of Kepler: death 140

§ 109. Fate of Tycho’s instruments and observations 141

§ 110. Estimate of Tycho’s work: the accuracy of his observations: improvements in the art of observing 141

§ 111. Improved values of astronomical constants. Theory of the moon: the _variation_ and the _annual equation_ 143

§ 112. The star catalogue: rejection of trepidation: unfinished work on the planets 144