calumniate his studies, and to grudge him his pension from the treasury. [40] Omne solum forti patria, et coelum undique supra est. The causes which led to this change of feeling on the part of Christian IV.'s advisers have not been explained by the biographers of Tycho. It has been stated, in general terms, that he had made many enemies, by the keenness of his temper and the severity of his satire; but I have not been able to discover any distinct examples of these peculiarities of his mind. In an event, indeed, which occurred about this time, he slightly resented a piece of marked incivility on the part of Henry Julius, Duke of Brunswick, who had married the Princess Eliza of Denmark; but it is not likely that so trivial an affair, if it were known at court, could have called down upon him the hostility of the King's advisers. The Duke of Brunswick had, in 1590, paid a visit to Uraniburg, and had particularly admired an antique brass statue of Mercury, about a cubit long, which Tycho had placed in the roof of the hypocaust or central crypt of the Stiern-berg observatory. By means of a concealed mechanism, it moved round in a circular orbit. The Duke requested the statue and its machinery, which Tycho gave him, on the condition that he should obtain a model of it, for the purpose of having another executed by a skilful workman. The Duke not only forgot his promise, but paid no attention to the letters which were addressed to him. Tycho was justly irritated at this unprincely conduct, and ordered this anecdote to be inserted in the description of Uraniburg which he was now preparing for publication. In the year 1592, Tycho lost his distinguished friend and correspondent the Prince of Hesse, and astronomy one of its most active and intelligent cultivators. His grief on this occasion was deep and sincere, and he gave utterance to his feelings in an impassioned elegy, in which he recorded the virtues and talents of his friend. Prince Maurice, the son and successor of the Landgrave, continued, with the assistance of able observers, to keep up the reputation of the observatory of Hesse-Cassel; and the observations which were there made were afterwards published by Snellius. The extensive and valuable correspondence between Tycho and the Landgrave was prepared for publication about the beginning of 1593, and contains also the letters of Rothman and Rantzau.