1588 his royal patron died, his rivals and enemies at court began to denigrate and revile him in every possible manner; so that he at length, weary of their unceasing persecutions, resolved to leave his country forever. He was at first received by the Vice-regent of Holstein, the learned Count Heinrich Rantzau, who placed at his disposal the castle of Wandsbeck. Here he published in 1598 a description of his observatories and instruments with illustrations, under the title "Astronomiæ Instauratæ Mechanica," and this superb work he dedicated to the German Emperor, Rudolph II. The latter invited him to come to Prague and promised him solid support for the continuation of his studies. Tyge Brahe accepted the invitation, but was soon disappointed in his expectations, for the emperor, who was continually in financial straits, was unable to keep the splendid promises he had made to him, and Brahe was obliged to work under rather discouraging conditions. In addition to this Tyge Brahe had in Keppler found an assistant, who soon discovered the errors on which Brahe's whole system was based. The latter did not long survive its master, who died in 1601, though in the eyes of the men of that age it possessed this advantage over the Copernican system, that it was in harmony with the Bible, while the latter conflicted with the Scriptures. And still Tyge Brahe made his name immortal through his services to astronomy, since he, in spite of his errors and his astrological daydreams, made positive contributions to the progress of science. For thirty years he had made regular and careful observations in regard to the movements of the planets. These he had recorded and used as the basis of calculations, and it was only on the foundation of these vast preliminary labors, which in accuracy surpassed all that practical astronomy had previously achieved, that Keppler was able to produce his celebrated theories and laws. As has been well said: "Tyge Brahe made the observations, Keppler discovered the law, and Newton conceived the nature of the law." That stupidity and reckless hatred, which had driven Denmark's greatest
