the Copernican system. But Kepler was not only a great genius, he was also a pure and noble character, and he never forgot in his writings to do honour to the man without whose labours he never could have found out the secrets of the planetary motions. On the title-page of his Astronomia nova de motibus stellæ Martis, he states that it is founded on Tycho's observations, and on that of the Tabulæ Rudolphinæ he mentions Tycho as a phœnix among astronomers.[1] And it was no exaggeration. Archimedes of old had said, "Give me a place to stand on, and I shall move the world." Tycho Brahe had given Kepler the place to stand on, and Kepler did move the world! And so it was with Kepler's labours in other fields, as we may see in that wonderfully interesting book, Ad Vitellionem Paralipomena, sive Astronomiæ Pars Optica, where Tycho's name is quoted so constantly as having supplied the materials. Kepler and Tycho had squabbled often enough while the latter was alive, but after his death this was forgotten, and Kepler's mind had only room for gratitude for having become heir to the great treasures left by Tycho. But on the other hand, it must be conceded that it was fortunate for Tycho's glory that his observations fell into the hands of Kepler. Longomontanus would doubtless have hoarded them
- ↑ "Tabulæ Rudolphinæ, quibus astronomicae scientiae, temporum longinquitate collapsæ, restauratio continetur, a Phoenice illo Astronomorum TYCHONE ex illustri et generosa Braheorum in Regno Daniae familia oriundo equite, primum animo concepta et destinata anno Christi mdlxiv., exinde observationibus siderum accuratissimis, post annum praecipue mdlxxii., quo sidus in Cassiopeiae constellatione novum effulsit, serio affectata, variisque operibus, cum mechanicis, tum librariis, impenso patrimonio amplissimo, accedentibus etiam subsidiis Friderici II. Daniæ Regis, regali magnificentia dignis, tracta per annos xxv. potissimum in insula freti Sundici Huenna et arce Uraniburgo, in hos usus a fundamentis exstructa, tandem traducta in Germaniam inque aulam et nomen Rudolphi Imp. anno mdiic. Tabulas ipsas, jam et nuncupatas et affectas, sed morte auctoris sui anno mdci. desertas, . . . perfecit, absolvit adque causarum et calculi perennis formulam traduxit Johannes Kepplerus." (Ulm, 1627.)
