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Tycho Brahe: a picture of scientific life and work in the sixteenth century/Chapter 10

< Tycho Brahe: a picture of scientific life and work in the sixteenth century



When Tycho arrived at Copenhagen in April 1597, he probably did not intend to make a long stay there, but merely to watch events for a short time. He can hardly have intended to settle in his house at Copenhagen and continue his work there, as he had the Isle of Hveen for life, and might as well have stayed there if he had any wish to remain in Denmark, unless, indeed, the troubles at Hveen had risen to such a height that the island had become odious to him. He had brought his instruments, chemical apparatus, and printing-press with him, but he does not appear to have commenced astronomical observations at the tower on the rampart close to his house. Probably he had not time to get any of the larger instruments mounted, as he tells us in the account of his leaving Denmark, as well as in several of his letters, that the Treasurer, acting in the name of the king, who was absent in Germany, forbade him to take observations in the tower on the rampart. He does not say on what pretext this was done, but possibly the Government did not wish him to settle permanently on any part of the fortification.[1] He is also said to have been bidden by the mayor, Carsten Rytter, to make chemical experiments in his own house, and Gassendi adds that he and his clergyman were subjected to personal annoyance, and that he was not able to obtain legal reparation; but this doubtless refers to the troubles at Hveen, and not to anything which happened at Copenhagen.[2] But an event which at first sight looks even more strange took place soon after. On the 2nd June, Thomas Fincke, Professor of Mathematics (afterwards of Medicine), and Iver Stub, Professor of Hebrew, were ordered to proceed to Hveen, as the king had learned that the peasants had damaged the instruments; they were to examine into this matter and report on it.[3] Their report is not known, and this expedition is not mentioned in any of Tycho's accounts of his expatriation, except in his poem Elegia ad Daniam (which will be mentioned farther on), and a garbled account of it may have reached him after his departure from Denmark. According to Gassendi, the two professors declared that the instruments were not only useless, but even noxious curiosities,[4] which probably only referred to the chemical apparatus. Fincke had in 1583, at Basle, published a Geometria Rotundi, in the preface to which he had addressed some highly complimentary sentences to Tycho, and the book is the earliest in which the words secant and tangent are proposed, while several new fundamental formulæ of trigonometry occur in it for the first time, so that the author must have been a man of considerable ability. [5] The mission of the two professors was no doubt caused by some disturbances at Hveen, which, perhaps, had more to do with Tycho's departure than we are aware of, and it is much to be regretted that we do not possess any account of these transactions except Tycho's own. Gassendi thinks that the report of the professors was the cause of Tycho's chemical experiments being forbidden; but this cannot have been the case, as the expedition of the two learned professors must have taken place after the 2nd June, and Tycho must have left Copenhagen either on that date or immediately after it, as he arrived at Rostock during the first half of June.

After having spent two or three months at Copenhagen, Tycho must have felt that there was nothing to be obtained by delaying his departure from Denmark any longer, and early in June 1597 he sailed for Rostock with his family, some students and attendants, about twenty persons in all, taking his instruments, printing-press, &c., with him. His principal assistant of late years, Longomontanus, who wished to study at German universities, had obtained his discharge with a kind testimonial from Tycho, dated at Copenhagen on the 1st June.[6] Among those who accompanied Tycho was a young Westphalian gentleman, Franz Gansneb Tengnagel von Camp, who had been with him at Hveen since 1595, and who afterwards became his son-in-law.

At Rostock Tycho had still friends from former days, though his correspondent Brucæus had died four years previously. But Chytræus was still alive, and on the 16th June he wrote a friendly letter, regretting that the state of his health prevented him from paying his respects to Tycho.[7] But the exiled astronomer found that though he was at once welcomed to Germany, he had not improved his position in Denmark, for immediately after his departure, on the 10th June, he was deprived of the prebend of Roskilde, which was conferred on the Chancellor, Friis, although the latter already enjoyed the best prebend in the chapter, and though the rules were that nobody could hold more than one prebend in any cathedral, that they were tenable for lifetime, and that the heirs of a prebendary should enjoy annum gratiæ after his death.[8] But here it must in fairness to the Government be recollected that Tycho had for years showed the most complete disregard of his obligations as a Prebendary, and that he had apparently left the country for ever in order to obtain employment abroad wherever he could get it. There was, therefore, some excuse for depriving him of this lucrative sinecure; but it certainly, on the other hand, seems to point to Friis as an enemy of Tycho's, since he made this an occasion for feathering his own nest.

When Tycho Brahe had been about a month at Rostock, he took a step which he probably ought to have taken long before, and addressed himself directly to King Christian IV. As it is of great interest, we shall give a translation of the letter, keeping as closely as possible to the words of the Danish original.[9]

"Most puissant, noble King, my most gracious Lord! with my willing and bounden duty most humbly declared. I beg most humbly to inform your Majesty, that whereas I had no opportunity of appearing before your Majesty before my departure, neither knew whether it might be agreeable to your Majesty or not, I am now obliged shortly to let your Majesty know in writing what I should otherwise humbly have stated verbally.

"Whereas from my youth I have had a great inclination thoroughly to study and understand the laudable astronomical art, and to put it on a proper foundation, and for that purpose formerly hoped to remain in Germany in order conveniently to do so, then your Majesty's father of laudable memory, when H. M. learned this, graciously desired and induced me to undertake and carry out the same at Hveen. Which I have done for more than twenty-one years with the greatest diligence, and at great expense, believing to have thereby shown that I liked best to do it to the honour of my own Lord and King and of my country. And your Majesty's father graciously intended and promised that whatever I started in the said art should by a foundation be sufficiently endowed and perpetuated on several good conditions which were graciously promised me, which your Majesty's Lady mother, my most gracious Queen, doubtless still remembers, and formerly has stated to the Privy Council of Denmark. For that I have received the public act of the Privy Council on parchment, confirming and further assuring me of this. Therefore I have since incurred great trouble and expense, even more than formerly, hoping that your Majesty when coming to the Government would be graciously pleased to let me and mine profit thereby. But it has turned out differently from what I had believed, about which I shall now only state the following. Your Majesty is doubtless aware that I have been deprived of what I should have had for the maintenance of the said art, and that I have been notified that your Majesty does not intend further to support it, in addition to much else which has happened me (as I think) without my fault or error. And whereas I, by the grace of God, shall have to carry to an end what I once with so much earnest and for so long have worked at, which is also known to many foreign nations and greatly desired, and I have not myself means for this, as I have been so reduced that I, notwithstanding the fiefs I held, have been obliged to part with my hereditary estate; therefore I trust that your Majesty will look to my necessities, and not be displeased with this my departure, as I for these and other reasons am greatly in need of seeking other ways and means, that what has been well begun may be properly finished, and that I may maintain my good name and reputation in foreign countries. But I have not departed with the intention of totally leaving my native land, but only to look for help and assistance from other princes and potentates, if possible, so that I may not too much be a burden to your Majesty and the kingdom. If I should have a chance of continuing my work in Denmark, I would not refuse to do so, for I should still as formerly much prefer to do as much as I can to the honour and praise of your Majesty and my own native land in preference to any other potentates, if it could be done on fair conditions, and without injury to myself. And if not, though it be ordained that I am to remain abroad, I shall always be subject to your Majesty with all respect and humility and humble capacity. Submitting also to the gracious consideration of your Majesty, that it is by no means from any fickleness that I now leave my native land and relations and friends, particularly at my age, being more than fifty years old and burdened with a not inconsiderable household, which I, at great inconvenience, am obliged to take abroad. And that which is still left at Hveen proves that it was not formerly my purpose and intention to depart from thence. Hoping, therefore, humbly, that when your Majesty considers these circumstances, your Majesty will be and continue my gracious Lord and King, and with all royal favour and grace incline toward me and mine. I shall always be found humbly true and dutiful to your Majesty to the best of my ability, wherever the Almighty sends me. The same good God who rules all worldly government grant your Majesty during your reign happiness, blessing, good counsel and design. Datum Rostock the 10th July 1597."

The same day Brahe wrote a letter (in Latin) to a young friend, Holger Rosenkrands (afterwards known as a writer on religious subjects), in which he thanked Rosenkrands for a letter he had just received, which showed that Ovid's words, "quam procul ex oculis, tam procul ibit amor," could not be applied to him. He had desired a painter to send a portrait of himself to Rosenkrands. He would like to know what was going on in Denmark, and what people said about his departure. He was still staying at Rostock, waiting for the return of the Danish embassy,[10] in order to speak to his brother Steen, and he had been advised by some people versed in state affairs not to apply to any foreign Government before he was assured as to the intentions of the Danish king; but if he found that his Majesty was unfavourable to him and his studies, he expected confidently to find advice elsewhere.

It would almost seem that Tycho already regretted having left Denmark, as he now made every effort to influence King Christian in his favour, though he had neglected to approach the king personally while he was still in the country. On the 29th July he wrote a letter in German to Duke Ulrich of Mecklenburg-Güstrow, the maternal grand- father of the king, reminding him of the visit which the Duke had once paid to Uraniborg, and stating that he had been obliged to leave Denmark for reasons which he did not wish to put in writing. For the present he had taken up his abode at Rostock, which he hoped was not displeasing to the Duke, who doubtless would regret that work, which was progressing well and which was valued by learned men all over Europe, should be so suddenly interrupted and almost come to nought. He therefore begged the Duke to advise him how this work might be continued, if not in Denmark, then somewhere in the Roman Empire, and promised in future publications gratefully to acknowledge any assistance the Duke would give him. At the same time Tycho wrote to the Duke's chancellor, Jacob Bording, whose father had been physician to King Christian III. of Denmark, and asked the chancellor to speak for him to the Duke. Bording answered at once, assuring Tycho of the good-will of the Duke, who would in a few days write to him as well as to the king. On the 4th August Duke Ulrich wrote to Tycho, expressing his sympathy, and asking whether Tycho would wish him to send off a letter to King Christian, of which he enclosed a copy. He could not express an opinion as to how the astronomical work might be carried on, but it would require the patronage of

[11] some great potentate. In his letter to the king the Duke merely asked his grandson not to allow Tycho's work to be interrupted, as it did great credit to the late king and the country, and was renowned among all nations.[12]

While Tycho Brahe was still at Rostock awaiting the result of his own and the Duke's letters to the king, he occupied himself in investing the ready money which he had brought with him from Denmark. As he repeatedly states that he had been obliged to part with his hereditary estate on account of the great outlay on buildings and instruments, which all his endowments did not cover, it would almost seem certain that his aunt and foster-mother, Inger Oxe, who died in 1591, must have left him a very considerable sum of money.[13] He found a very convenient way of investing his money, as the Dukes Ulrich and Sigismund August, as guardians of the young Dukes Adolph Friedrich I. and Johann Albrecht II. of Mecklenburg, happened to require money, and were willing to borrow from Tycho. In the summer of 1597 they opened negotiations with him for the loan of 10,000 "harte Keichsthaler" (i.e. of full value, not clipped). As a prudent man, Tycho wanted proper security, and demanded a bond, by which ten well-known men should declare themselves and their heirs bound to him in the sum of 10,000 thaler; but as it was not customary in Mecklenburg for sureties to bind their heirs, he had to give up that point. As it took time to procure the consent and the signatures of the sureties, Brahe agreed to pay the money on receiving a temporary receipt from the two ducal guardians, and a mortgage on the county of Doberan; but when this was settled and two officials came for the money, he would not pay it, as the receipt did not contain a certified copy of the bond to be given by the ten men, and did not specify the interest to be paid. At last everything was settled and the bond was delivered, dated the 24th August 1597, to "Tycho Brahe auf Knustorf im Reiche Dänemark erbgesessen," after which the money was paid.[14]

In the meantime the plague had appeared at Rostock, but Tycho still lingered there, awaiting the reply to his letter to the king. If, before he took the decisive step of removing his family, his great treasure of observations, and nearly all his instruments out of the Danish dominions, Tycho had addressed himself to the king, who was of an open, generous nature, it is not unlikely that he might have been treated very differently; but to an impartial observer it is not strange that the king should be offended with a subject whose previous behaviour had been far from faultless, who had left the country in a huff in order to carry his talents to the most profitable market, and who now declared himself willing to forget the past and come back if it was made worth his while. Of the interference of his grandfather the king took no notice whatever,[15] but to Tycho's own letter he sent on the 8th October the following answer, which we also translate literally.[16]

"Christian the Fourth, by the grace of God of Denmark and Norway, the Vends and the Goths, King, &c. Our favour as hitherto. Know you that your letter which you have addressed to us sub dato Rostock the 10th day of July last, has been humbly delivered to us this week, in which among other things are counted up, first, that you had no opportunity to speak to us before you left this kingdom, neither knew whether it were convenient to us or not; therefore you have humbly wished to let us know your case in writing, and [you add] that we are doubtless aware that you have lost whatever allowance you hitherto have had for the maintenance of the astronomical art, also that we will not continue to support the said art, and other things which unexpectedly have occurred and have happened to you with- out any fault or error of yours, as you think. Furthermore, that you have not yourself the means to perfect the said art at your own expense, and even though you had your former benefices, you have yet been so reduced as to have had to part with your estate. And whereas you for the said reasons are obliged to seek in other places from foreign potentates and lords help, assistance, and counsel to promote the astronomical art, then you beg that we will not with displeasure look upon your journey, particularly as you will not altogether leave your native land. Furthermore, you state that if it may be granted to you in this kingdom to continue your work, then you would not refuse it, but grant that honour to us and your native land, if it could be done on fair conditions and without injury to you, as your lengthy letter furthermore details it. Now we would graciously not withhold from you, first, as regards that you have not had an opportunity of speaking to us before you left the kingdom, and that you were not aware whether it would be agreeable to us or not: You must well remember that you were staying for some weeks in our city of Copenhagen before you left the kingdom, and not only did not ask authority from us to leave the country, as you should have done, but never even spoke to us except on the one occasion when the peasants of Hveen and you were in court before us, and you were commanded and ordered to appear before us at the castle. And although you do not blush to make your excuse for this in a manner as if you were our equal, we desire in this letter to let you know that we are aware of that, and that we expect from this day to be respected by you in a different manner, if you are to find in us a gracious lord and king. As regards your not doubting that we are aware that you have lost some fiefs you had held, and your thinking that it happened through no fault or error of yours; you remember well what complaints our poor subjects and peasants at Hveen have had against you, how you have acted about the church there, of which you for some years took the income and tithes and did not appoint any churchwarden, but let it stand ruinous; also took the land from the parsonage; and partly pulled down the houses, and the parson who should live there and use the land to keep himself and his wife, him you have given some pennies per week and fed him with your labourers, so that there have been during some years many parsons, who yet did not receive a call from the congregation in accordance with the ordinance, nor were lawfully dispossessed. In what way the words of baptism for a length of time have been omitted, against the established usage of these kingdoms, with your cognisance, is too well known to everybody. Which things, as well as others, which have occurred on that poor and small land, and were known to us for a good while before it became publicly known, have caused us to grant our tenants and the crown's in fief to others who would keep them under the law, right, and established custom.[17] With regard to your not being wealthy enough to promote the astronomical art by your own means, but sold your hereditary estate while you yet held your fiefs, so that you have left the kingdom to ask for help from foreign potentates, and not intending to leave your native land altogether, which journey you humbly ask us not to take umbrage at: there is great doubt whether you have spent the moneys you received for the property you sold on astronomical instruments, as it is said here that you have them to lend in thousands of daler to lords and princes, for the good of your children and not for the honour of the kingdom or the promotion of science. Also it is very displeasing to us to learn that you seek for help from other princes, as if we or the kingdom were so poor that we could not afford it unless you went out with woman and children to beg from others. But whereas it is now done, we have to leave it so and not to trouble ourselves whether you leave the country or stay in it. Lastly, as you humbly state that if it might be permitted you to finish your work in this kingdom you would not refuse if it could be done without injury to you; now we shall graciously answer you that if you will serve as a mathematicus and do what he ought to do, then you should first humbly offer your service and ask about it as a servant ought to do, and not state your opinion in such equivocal words (that you will not refuse it). When that is done, we shall afterwards know how to declare our will. And whereas your letter is somewhat peculiarly styled, and not without great audacity and want of sense, as if we were to account to you why and for what reason we made any change about the crown estates; and we besides remember how you have published in your epistles various nonsense about our dear father, to the injury both of his love and of yourself; now we by this our letter forbid you to issue in print the letter you wrote to us, if you will not be charged and punished by us as is proper. Commending you to God. Written at our Castle of Copenhagen the 8th October Anno 1597. Under our seal,


(Address)—" To our beloved, the honourable and noble Tyge Brahe of Knudstrup, our man and servant."

The harsh and angry tone of this letter shows how completely the king's mind had become estranged from Tycho; and no matter how badly Tycho may have treated his inferiors, the fact remains that he was in his turn treated with severity and a want of appreciation of his great scientific merit which is inexcusable. It could not be expected that the king or his advisers should have been able to appreciate the true value of Tycho's scientific labours, but they could not help being aware that he enjoyed a world-wide reputation, such as no Dane had ever acquired before; and if he was a bad landlord, they might have endowed him in some other way. But this is neither the first nor the last time that a Government has given science the cold shoulder, since even in later and much more enlightened times statesmen of all nations not unfrequently have distinguished themselves by a sovereign contempt of science. But all the more let us admire the truly enlightened mind of Tycho's great benefactor and friend, King Frederick the Second, whom he had unfortunately lost too early. King Christian seems to have felt personally offended with Tycho Brahe for having first retreated to a distance and then attempted to make terms with him. But it is not impossible that Tycho may have thought of Vedel, who in 1595 had not only been deprived of his office of historiographer for delaying too long to write the Danish history, but had even been forced to deliver up all the materials which he had been collecting for years. Possibly Tycho wished to bring his great treasure of observations out of the reach of envious people, who might suggest that it had been gathered at the public expense, and therefore was public property; but by doing so he destroyed the bridge behind him, and could now only look abroad for a place to continue his labours.

As Tycho had no reason to remain any longer at Rostock, where the plague besides made the stay unpleasant if not dangerous, he now accepted the invitation of Heinrich Rantzov to reside for a while in one of his castles. Of these, Warndsbeck, which had been rebuilt not long before, seemed to Tycho the most convenient, as it was situated close to Hamburg (only two or three miles north-east of it), and the intercourse with foreign countries, therefore, was easy. As Rantzov, who was a very wealthy man, had spent great sums on accumulating books and treasures of art in his various castles in Holstein and Slesvig, Tycho found at Wandsbeck (or Wandesburg, as the new castle was called) not only a comfortable dwelling, but also one in which the owner's refined tastes had created a home which might to some extent bear comparison with the one he had left for ever. Tycho removed with his family and belongings to Wandsbeck about the middle of October 1597, and met a former acquaintance there in the person of Georg Ludwig Froben (Frobenius) from Würzburg, who six or seven years before had visited Uraniborg after studying at Tübingen and Wittenberg. He was at that time probably employed by Rantzov at Wandsbeck in literary work, and he settled in the year 1600 as a printer at Hamburg, where he remained till his death in 1645.[18]

Tycho could now think of resuming the observations which had been interrupted seven months before. On the 20th October he wrote a short statement of the causes of this interruption and of his departure, which we have already quoted,[19] and a long poem "Ad Daniam Elegia," in which he taxes his native land with having rewarded him with ingratitude. It begins thus:[20]

"Dania, quid merui, quo te, mea Patria, læsi
     Usque adeo ut rebus sis minus æqua meis?
 Scilicet illud erat, tibi quo nocuisse reprendar,
     Quo majus per me nomen in orbe geras?
 Dic age, quis pro te tot tantaque fecerat ante,
     Ut veheret famam cuncta per astra tuam?"

The writer next inquires who is to make use of the precious things which he has left behind. "Somebody has been sent to Hveen who was believed to know Urania's secrets; he came, and when he beheld the great sights (though but a few are left), he stared with wonder. What could an ignorant man do, who had never seen such things? He inquires their name and use, but lest he should seem to have been sent thither in vain, he sneers at what he does not comprehend, probably instructed by my enemy, who already before has injured me." The poem further alludes to all he has done for science, and how little his Herculean labours have been valued; how he has cured the sick with- out payment, and suggests that this perhaps has roused the envy of his enemies. He regrets that his ungrateful country shall lose the honour which he conferred on it, but he looks to the future without fear, as the whole world will be his country and he will be appreciated everywhere. He exonerates the king from all blame, but there are a few others whom he never injured, but who yet have done him all the harm they could. Finally, he thanks Rantzov for having so hospitably received him.

The statement about the interruption of the observations and the elegy were copied into the volume in which the observations of the years 1596 and 1597 were written, and copies of the poem were sent to various correspondents. Though it was probably not intended for the eye of King Christian, it fell into his hands by accident. On a copy of the poem which Tycho in the following year sent to Joseph Scaliger he added a note to the following effect: Rantzov got a copy of the poem as soon as it was written, and had it stitched in a calendar of his,[21] and when the king in the course of the winter paid a visit to Rantzov at one of his other castles in Holstein, he happened to find the book lying open on the library table. The king took it up, and when he saw the poem with Tycho's signature underneath, he read the whole of it thoughtfully and slowly, though he on other occasions would not have been affected by such things.[22] Having read it, he silently put down the book and never spoke to Rantzov about it, nor did he in conversation allude to Tycho Brahe. When Rantzov was told that the king had seen the poem, he was much vexed, but Tycho on hearing it only hoped that the king had understood all the allusions, and expressed himself ready to send the king a copy.[23]

Though Tycho Brahe had been unsuccessful in his application to the king and in his attempt to use the influence of Duke Ulrich of Mecklenburg, he still tried to bring all the influence he could to bear on him. In December 1597 he went on a visit to Rantzov at Bramstedt in Holstein, where he met Margrave Joachim Frederic, who shortly afterwards became Elector of Brandenburg, and his consort, who were on their way home after attending the wedding of their daughter and King Christian at Haderslev in Slesvig, on the 27th November. On the 22nd December Tycho handed the Margrave a letter in which he expressed his regret to find that the king was displeased with him for leaving Denmark, though any one might know that he would not without cause have left his home with wife and children, and at the age of fifty. But as it perhaps had been so ordained by God, he was content, and had no wish to be reinstated, and even if that should be done, he would be very unwilling to live any longer at Hveen, and always to stay there.[24] But he would ask the Margrave to write to the king that he would, though abroad, continue to do all he could for the honour of his country, and it might perhaps elsewhere be done as well, if not better, and much more conveniently and quietly than in Denmark. If the king would carry out his father's intention, and would permanently endow Uraniborg, Tycho would see that the work should be carried on well, if not by himself, at least by one of his [family], and he would let the four great instruments remain there, and supply others as well. In that case he hoped the king would endow the observatory with canonries in accordance with the promise of the Government during the interregnum. But if the king did not desire to keep up the observatory, he hoped he might remove the four instruments, and that he might receive some compensation for all the trouble and expense he had gone to.[25]

With this letter has been preserved another memorandum of Tycho's reasons for going abroad, which he doubtless gave the Margrave with the letter.[26] In this memorandum it is stated that Tycho had, at the wish of King Frederick, settled at Hveen, where he had erected a number of costly buildings and constructed more than fifty fish-ponds, which were a great boon to the island, as often there was formerly a scarcity of fresh water. All this, as well as his instruments, had cost over 75,000 daler, though the king and Council had only paid 10,500 daler towards it.[27] When the Privy Council, shortly after the king's death, had pledged itself to recommend the young king, when he attained his majority, to perpetuate the observatory, Tycho had in the following eight years even expended more than before. But after the coronation he lost first his Norwegian fief, which had brought him in about 1000 daler annually, and soon after that he also lost his pension of 500 daler. His removal to Copenhagen is then mentioned, and how he was during the king's absence forbidden to continue his work there. Then, when he left for Germany, the Chancellor got his prebend, which was worth about 700 daler and ten Danish læster corn.[28] King Frederick had under his hand and seal promised him the first vacant prebend in the Cathedral of Lund, but this had been ignored afterwards. He had met with these and other troubles, which he did not wish to put in writing, and he could only conclude that there was no good-will in Denmark towards him or his science, though he was willing to excuse the king, and to believe that all arose from the envy and hatred of his enemies. He would therefore leave all to God, and pray for His help and blessing to continue his work.

On the 25th January 1598, the Elector of Brandenburg (who had just succeeded to this dignity on the death of his father) wrote to King Christian enclosing Tycho's letter, which he asked his son-in-law to consider favourably. He also wrote to his daughter, and asked her to put in a good word for Tycho. These letters were sent under cover to Friis and Valkendorf, with a short note asking them to do whatever they could in this matter. On the 4th February the Electress wrote to the king asking him to give a gracious answer to Tycho Brahe's petition, and to her daughter the queen she wrote in nearly the same terms, asking her to use her influence with the king to that effect.[29] What answers were sent to these letters is not known, but at any rate they did not lead to anything.

In the meantime Tycho had resumed the observations at Wandsbeck, the first being made on the 21st October 1597. During the first few months he only employed a radius, as in the early days of his youth, before he had got a number of good instruments together, and he was even obliged to observe the important opposition of Mars in this manner, as he had not yet got the heavier instruments transported to Wandsbeck and erected in suitable places. By the beginning of February 1598 this was done,[30] and he was again able to use quadrants for determining the time by altitude observations, instead of (as during the previous months) by watching when the pole-star and another star were in the same vertical. He also laid aside the radius for the more accurate sextant, and set up an equatorial armilla for observing the sun. On the 25th February 1598 a solar eclipse took place, which was total in the middle of Germany, while in Holstein about nine-twelfths of the solar diameter was eclipsed. Tycho observed this eclipse, and received observations from his former pupils, Longomontanus, who at that time was staying at Rostock, and Christen Hansen of Ribe, who observed it in Jutland, and who had formerly observed the comet of 1593 at Zerbst. It appears that Tycho got some kind of information about this eclipse from somebody at Hveen, perhaps from David Petri (Pedersen), whom he had left in charge of the buildings and other property on the island, as Tycho afterwards wrote both to Magini and Kepler that the eclipse had been observed at Hveen from beginning to end (while only the beginning was seen at Wandsbeck owing to clouds), and that the time of beginning and end agreed well with his own tables.[31] With the exception of this eclipse of the sun and two of the moon, and a few meridian altitudes of the sun, the planets only were observed at Wandsbeck. Tycho felt that the thousand star-places were enough to have to show to the world, and he felt that observations of the planets were of greater value to complete the material accumulated at Hveen. He was assisted at Wandsbeck by Johannes Müller, mathematician to the Elector of Brandenburg, who had visited him at Hveen in 1596, and whom he was requested by the Electress to train not only in chemistry but also in the preparation of medicines.[32] The distinguished astronomer David Fabricius of Ostfriesland also visited Tycho at Wandsbeck, but probably only for a short time.

In addition to the observations, Tycho devoted his time at Wandsbeck to the preparation of the illustrated description of his instruments, which he had for years intended to publish, and which it seemed particularly desirable to issue now, in order to sustain his reputation and impress learned and influential men with the magnitude of his scientific work and its great superiority over that of previous observers. Woodcuts of a number of the instruments had already been prepared at Uraniborg, and some of them had been inserted in his books on the new star and the comet of 1577. Some engravings were now made of other instruments not yet figured, and the text was soon put together by enlarging the account formerly prepared for the Landgrave. As Tycho had brought his printing-press with him, he was able to have the book printed under his own eyes at Wandsbeck by Philip von Ohr, a printer from Hamburg. Early in 1598 the Astronomiæ instauratæ Mechanica was ready, a handsome thin folio volume, slightly larger than the reprint of 1602, and now extremely scarce, so that the number of copies printed can hardly have been considerable.[33] The book was dedicated to the Emperor Rudolph II., whom Tycho was now specially anxious to interest in his labours. The dedication, which is dated the 31st December 1597, refers shortly to the instruments of the ancients and the limited accuracy attainable with them, and gives a summary of the contents of the book. Then follow (after a poem by Holger Rosenkrands) figures and descriptions of the seventeen principal instruments used at Uraniborg and Stjerneborg; of the sextant used in 1572–73 (two figures), of the great quadrant at Augsburg, and of a mounting once used for the largest azimuthal quadrant, and superseded by the one figured as No. 7. We shall not here dwell on these descriptions of Tycho's instruments, as they will be considered in some detail in the last chapter, and some of them have already been alluded to in previous chapters. It was natural that Tycho should at that time, with an un- certain future before him, point with some satisfaction to the convenient construction even of the larger instruments, which enabled him to take them asunder for the sake of transportation to different parts of the world. For an astronomer must be cosmopolitan ("Oportebit enim Astronomum esse κοσμοπολιτήν"), as among statesmen there are rarely found any who admire his studies, but frequently those who despise them. But the student of this divine art should not care about the opinions of ignorant people, but only think of his studies, and if interfered with by politicians or others, let him move himself and his belongings to some

other place, preferring his heavenly and sublime endeavours even to his native soil, and remembering that—

"Undique terra infra, cœlum patet undique supra
 Et patria est forti quælibet ora viro."[34]

After the illustrated description of instruments follows a short account of six smaller portable instruments and an engraving and description of the great globe. Tycho next gives a sketch of his life from his youth onwards, his travels, and how he became settled at Hveen, and passes in review the principal results of his observations;[35] the improved elements of the solar orbit; the discovery of a new inequality in the moon's motion; the variability of the inclination of the lunar orbit and of the motion of the nodes; the observed accurate positions of a thousand fixed stars; the explosion of the time-honoured error about the irregularity in the precession of the equinoxes (trepidatio); the accumulation of a vast mass of carefully planned observations of the planets in order to have new tables of their motions constructed; and lastly, the observations of comets proving them to be much farther away from the earth than the moon. This was indeed a proud record of the twenty years' work at Hveen, and was sufficient to show the world that Tycho Brahe was worthy to rank with Hipparchus, Ptolemy, and Copernicus.

After this review of his labours, Tycho prints a letter from the late Imperial Vice-Chancellor Curtius and several from Magini,[36] and a short abstract of a letter from Padua (of December 1592), "from a certain Doctor of Medicine then staying there" (he did not like to add, "of the name of Gellius"). From this it appeared that the Government of Venice intended to send an observer to Egypt, and Tycho takes occasion to address a suggestion to the Venetians that they should cause the latitude of Alexandria to be redetermined, to see whether there had been any change in this quantity since the time of Ptolemy, as maintained by some, and he offered to assist them in this undertaking with instruments and advice. The book is then wound up with a description, with views and plans, of Uraniborg and Stjerneborg (to which he adds some remarks about the necessity of a good site for an observatory), a map of Hveen, and a short account of his transversal divisions and improved sights.[37]

In the original edition of this book there was no engraved portrait of Tycho, but in several of the copies which he presented to distinguished or influential persons a portrait in water-colours is pasted on the back of the title-page. This portrait is much larger than any published portraits, and represents him bareheaded, very bald (with a small tuft of hair over the middle of the forehead), and a very woe-begone countenance. It does not offer much resemblance to the well-known engraving by Geyn of Amsterdam of 1586, which appears in Tycho's Epistolæ and in the edition of the Progymnasmata of 1610, which represents him standing in a kind of arch on which the arms of the families of Brahe and Bille, and of the families connected with them, are suspended. This engraving has been reproduced in Gassendi's book.[38] Another portrait of Tycho Brahe, but of unknown date, was an oil-painting in the historical portrait gallery at Frederiksborg Castle, which was destroyed in the great fire of that castle in 1859.[39] In the letter (quoted above) which Tycho wrote to Rosenkrands from Rostock, he mentioned that he had ordered a painter to paint his portrait, and would send it to Rosenkrands when it was ready. This picture is probably the same which in the following century was preserved in the library of King Frederick III., and in the corner of which was an emblematic design with the following inscription:—

"Stans tegor in solido, Ventus fremat, ignis & unda.
Anno MIƆXCVII, quo post diutinum in patria
Exilium demum pristinæ libertati restitutus fui
Tyclio Brahe Ot. "[40]

This portrait (or a copy of it) was found in England in 1876, and now belongs to the Royal Observatory, Edinburgh.[41] A full figure portrait occurs in Baretti Historia Cœlestis, representing Tycho leaning on a large sextant; the face resembles the engraving by Geyn, and the picture is apparently copied from a water-colour drawing on parchment in a copy of Tycho's Progymnasmata in the Strahof Monastery at Prague.[42]

Tycho was not content with issuing the description of his instruments, but as the first volume of his book ( Progymnasmata), in which the catalogue of 777 stars occurred, was still unfinished, he thought it desirable to distribute a limited number of manuscript copies of his catalogue of stars. It was probably for this purpose only that he had before leaving Hveen got a number of stars hastily observed in order to exhibit the places of a thousand stars, and not be inferior to Ptolemy with his 1028 stars. This catalogue of longitudes and latitudes of 1000 stars for the year 1600 was now neatly copied on paper or parchment by his assistants, and to it were added tables of refraction and precession, of the right ascension, and declination of a hundred stars for the epoch 1600 and 1700, and a catalogue of longitude, latitude, right ascension, and declination of thirty-six stars according to Alphonso, Copernicus, and himself, for the sake of comparison.[43] The lengthy introduction to this manuscript work was in the form of a dedication to the Emperor Rudolph II., dated the 2nd January 1598.[44] In this Tycho reviews the successive star-catalogues of Hipparchus and his successors down to and including "incomparabilis vir Nicolaus Copernicus," and he remarks that in reality nobody after Hipparchus has observed any great number of stars, but that Ptolemy, Albattani, Alphonso, and Copernicus had merely added precession to the longitudes, which circumstance in connexion with the limited accuracy of the catalogue of Hipparchus, and the numerous great errors which had crept into it, made it desirable to have a new star-catalogue prepared, in which the positions of the stars were given with the greatest accuracy now attainable. This Tycho had done, and offered it as a New Year's gift to the Emperor. The catalogue and the printed book, Mechanica, were sent to the Emperor by the hands of Tycho's eldest son, who also was the bearer of a letter, dated 2nd January 1598, in which Tycho stated that he had been obliged to leave his country and had come to Germany, where he hoped it might be granted him to complete his labours under the auspices of the Emperor.[45] About the same time Tycho sent magnificently bound copies of the star-catalogue to the Archduke Matthias, to the Vice-Chancellor Corraducius, to Wolfgang Theodore, Archbishop of Salzburg,[46] the Bishop of Lübeck, and to other influential men in Austria and Germany, to the King of Denmark, Prince Maurice of Orange,[47] Joseph Scaliger,[48] Magini, Kepler, two years later to the Elector of Saxony, &c. As already remarked, the Progymnasmata, which was not published until after Tycho's death, only contained 777 stars, but Kepler in 1627 published the thousand star-places in his Tabulæ Eudolphinæ; while it is most significant that Longomontanus, Tycho's principal assistant, in his Astronomia Danica, only inserted the 777 stars, doubtless because he knew well how worthless the additional star-places were. The handsome manuscript volumes entitled "Tychonis Brahe Stellarum octavi orbis inerrantium accurata restitutio, Wandesburgi, Anno CIƆIƆIIC," were chiefly intended as Advertisements, and it would be perfect waste of time to collate the various copies with a view to correcting Kepler's edition.[49]

When Tycho sent a copy of this catalogue to King Christian,[50] he probably also sent a letter to the king, of which a draught is now preserved in the University Library at Basle, dated the 7th February 1598.[51] In this Tycho, after offering his congratulations on the king's marriage, remarks that the troubles which he had met with in the preceding year were perhaps ordained by fate, since it was the third annus climactericus (i.e., the twenty-first year), since the foundation of Uraniborg. He, however, thanked the king for not having impeded his journey when he found it necessary for his studies to go abroad, though he regretted that his letter from Rostock had not been found satisfactory; but to show his feeling for his country and king, he now forwarded two books which had been recently completed.

While Tycho in this manner paid his respects to the king, notwithstanding the want of consideration with which the latter had treated him, he did not hesitate to write to Valkendorf to try to obtain some arrears of rent still due to him. In this letter, dated the 28th May 1598, Tycho first thanks the Treasurer for all the kindness he has shown him, and for the help he has given the steward at Hveen, who had informed Tycho that he had in several cases concerning the tenants there been supported by the authority of the Treasurer. "If it were known how contrary and disobedient the peasants on that little land are, and what I have suffered from them all the time I lived there, and yet had patience with them, and been more kind to them than they deserve, then perhaps people would think differently about them than they have done." Tycho next asks the Treasurer to instruct the Governor of Bergen to order half a year's rent of the Nordfjord estate to be paid to him or his agent,

as it is still owing to him; and in conclusion he apologises for giving so much trouble, but he expects everything good from Valkendorf, and is sure that the latter will help him in everything just, and right, and feasible.[52] The whole tone of this letter seems to show with certainty that Valkendorf cannot have been a declared enemy of Tycho's, as the latter was of too haughty a disposition to condescend to write so pleasantly to an avowed and open enemy; but on the other hand, this does not prove that Valkendorf did not assist in depriving Tycho of his great endowments.

Some time before this last appeal was dispatched to Denmark, Tycho had on the 24th March 1598 written to Longomontanus. He had heard from the Jesuit Monavius of Breslau that Longomontanus had arrived there and had had a look at Wittich's books, and Tycho therefore wished to know whether there were any manuscripts among them, and whether they were to be sold. He also inquired whether Longomontanus had seen the recent slanderous publication of Reymers Bär, which was too far beyond the limits of decency to deserve a refutation; still it might be well for Longomontanus to put in writing all he had heard from his colleagues at Hveen about that person and his doings, as he himself might have forgotten some of the circumstances through all the troubles he had met with. Finally, he desired Longomontanus to come to him at Wandsbeck as quickly as possible, as he had something very important to discuss with him, and if he had not sufficient money, he was to borrow some or pawn something, and Tycho would settle about it afterwards, and he would not detain him long, as he did not himself intend to remain long at Wandsbeck. He had Johannes Müller from Brandenburg with him in charge of his observatory, but he hoped Longomontanus would not disappoint him, and he might bring with him a copy of Everhard's Ephemerides, which he had seen mentioned in a Frankfurt book-list, but which could not be had at Hamburg.[53] Gassendi suggests that Tycho may have wanted the help of Longomontanus to complete the chapter of the Progymnasmata on the lunar theory, where some sheets were still unfinished, while the recent eclipses had shown that this theory was still capable of further improvement.

While Tycho Brahe was living at Wandsbeck, his host not only tried to make his stay there agreeable,[54] but also did his best to assist him in finding a permanent abode, and the pecuniary support necessary to enable him to resume his labours on the same scale as formerly. Rantzov wrote to the Elector of Cologne, and asked him, to use his influence with the Emperor in favour of Tycho, and to endeavour to interest the Austrian Privy Councillor, Barwitz, in the cause of the exiled astronomer. At the same time Tycho wrote himself to his friend Hagecius, and explained how he was situated, in order that the physician to the Emperor might speak to his master, and also enlist the sympathy of the Vice-Chancellor Corraduc. In order not to neglect any chance, Tycho also sent one of his disciples, Franz Tengnagel, a native of Westphalia, to Prince Maurice of Orange to present copies of the Mechanica and the star-catalogue to the Prince, together with a letter from the author. The Prince answered that he would endeavour to persuade the States General to invite Tycho to settle in the Netherlands, and a similar answer was sent by the Advocate of Holland (or Grand Pensionary, as he was afterwards called), Olden Barneveld, to whom Tycho, as a prudent politician, had also written and sent his books. Joseph Scaliger, who five years before had been called to Leyden as a professor, also wrote that he would do his best, but he feared that the slow procedure of the States General would deprive the country of so great an honour and himself of the pleasure of being associated with a great man. In the meantime the Emperor had desired Corraduc to answer Tycho that he would willingly receive him and see that he should want nothing for the furtherance of his studies. In the course of the summer Tycho not only learned this from Corraduc, but also received a letter from Hagecius urging him to come to Bohemia as soon as possible, while the Elector of Cologne replied to Rantzov that he had every hope of Tycho's being well received by the Emperor, and added that if Tycho, against all expectation, should not find his work liberally enough supported by the Emperor, then he would himself promote it to the best of his ability. Tycho therefore, on the 23rd August, wrote to Scaliger, sending him his books (even the unfinished one), and thanked him for his kindness, and assured him that he would not have been disinclined to go to Holland, but that he had now been invited by the Emperor and would soon set out for Prague. But if this journey should not lead to the expected result, and the States would make him a liberal offer, then he would willingly come to them with his astronomical apparatus.[55]

Tycho was still at Wandsbeck on the 14th September 1598, on which day he wrote to Duke Ulrich of Mecklenburg to thank him for a letter of recommendation to the Emperor, and to ask him to accept a copy of the star-catalogue, with the same favour with which he had received his book on instruments.[56] Not long afterwards Tycho left Wandsbeck with his sons, his students, and a few small instruments, leaving for a while longer his wife and daughters and the greater part of his luggage in the kind charge of his host, who, however, died on the 1st January following. He travelled himself as far as Dresden, where he learned that there was pestilence and dysentery at Prague, and that the Emperor had retired with his court to Pilsen; and when he wrote to Corraduc to announce his arrival, the Vice-Chancellor, at the Emperor's command, requested him to remain at Dresden until the epidemic was over. From Dresden Tycho wrote on the 28th November to Magini, with whom he had held no communication for about seven years, and told him that he had not finished his book yet, as the theories of the planets were not yet complete. He also gave a short account of the cause of his leaving Denmark, and added in a postscript that Tengnagel, who was the bearer of the letter, would verbally communicate some- thing secret. This turned out to be that Tycho would like some Italian to write a eulogy of him, for which Magini two years later recommended Bernardino Baldi, who was going to write the lives of great mathematicians.[57]

Tycho did not remain long at Dresden, but preferred to spend the winter at Wittenberg, where he had still friends from his two former visits. In the first week of December 1598[58] he went to Wittenberg with his sons and assistants, entered his own name and those of his two sons on the roll of students in the University,[59] and was lodged in the house which formerly had belonged to Melanchthon, and now belonged to his son-in-law, Peucer, and where the physician Jessenius (Johannes Jessinsky) lived at that time. In the meanwhile Longomontanus had proceeded to Wandsbeck, but on his arrival he only found Tycho's wife and daughters there. He remained with them until Tycho's servant Andreas arrived with letters requesting them to set out for Wittenberg, upon which Longomontanus accompanied the ladies as far as Magdeburg, and then returned to Denmark, where he observed the lunar eclipse on the 31st January following in his native village. On the 31st December 1598 Tycho wrote to him in reply to a letter he had just received, in which Longomontanus had informed him that a printer at Hamburg, who had been intrusted with the printing of the sheets relating to the lunar theory, had performed his task very badly, so that it would be necessary to do it over again. Tycho therefore wrote that he would get it done at Wittenberg.[60] He thanked Longomontanus for his attention to the ladies, and offered to supply him with means for studying at some German University until he had himself become quite settled at the Emperor's court. He also expressed his pleasure at hearing that Longomontanus intended to write a refutation of the so-called defence of the Scotch opponent, and he wished that it might be finished soon, so that it might be printed at Wittenberg as an appendix to the volume on the comet of 1577.[61] On the 11th January 1599 Tycho again wrote to Longomontanus asking him soon to come to Wittenberg at his expense, and offering to get him the professorship at Prague now held by Reymers Bär, who would doubtless soon make himself invisible; or if Longomontanus would prefer a post at Wittenberg, Tycho would see that a professor there, who was not disinclined to go to Prague, was appointed to Reymers' post, and Longomontanus might then get the post vacated at Wittenberg. None of these proposals were, however, accepted, and Longomontanus did not join his old master until the latter had been at Prague for some time.[62]

It was not difficult for Tycho to foresee that Reymers would not care to await his arrival at Prague. When the former swineherd saw the expressions which Tycho and Rothmann had used about him in their letters, and which were made public by the printing of these, he naturally became furious, and in 1597 he published at Prague, where he had in the meantime become Professor of Mathematics, a book De astronomicis hypothesibus, in which he gave his fury full play.[63] The title-page shows the motto (in Greek), "I will meet them as a bear bereaved of her whelps" (Hosea xiii.), and indeed the language of the author is bear- like enough. First he tells how he discovered the Tychonic system on the 1st October 1585, and explained it to the Landgrave on the 1st May 1586, after which a brass model of it was made by Bürgi, and he suggests that Tycho may have heard of it through Rothmann (or, as he calls him throughout the book, Rotzmann, i.e., Snivelman). Afterwards he maintains that Tycho had merely imitated the system of Apollonius of Perga, and that Helisæus Röslin had recently with equal coolness claimed the same as his own.[64] He attacks Tycho and Rothmann with the coarsest abuse, and is very anxious to disprove that he was ever in Tycho's employment, as Rothmann had believed, and tells how he came to Hveen with Erik Lange. It appears that Tycho cut him short during a dispute with the remark that "those German fellows were all half-cracked,"[65] and that he generally went by the appellation of "Erik's Dreng" (i.e., Erik's boy), and he adds proudly, "Jam non sum Jerix Dreng sed Imp. Rudolphi II. Mathematicus." To Tycho's accusation that Reymers had stolen the idea of the new system during his stay at Uraniborg, he answers that in that case it would have been stolen from him again, since Tycho, before his departure, got somebody to search his papers at night, when nothing was found but some plans of the buildings. The only way he could ever have spoken ill of Tycho must have been by joking about his nose, of which the upper part had been cut off, and he indulges in some scurrilous remarks about the facilities which Tycho possessed for taking observations through his nose without sights or instruments. But other parts of the book, like the "Fundamentum astronomicum,"[66] showed that Reymers was a very skilful mathematician, who deserves every credit for having by his own exertions, and apparently without enjoying the advantages of regular teaching, raised himself from the position of a swineherd to that of a professor at Prague. It is easy to understand that his venomous attack must have been doubly annoying to Tycho at the particular moment when it was published and when he was anxiously seeking a new home. Tycho therefore began to collect evidence to show that his enemy had really behaved in a suspicious manner while at Hveen, and a document has been preserved, drawn up and signed before a notary at Cassel by Michael Walter, secretary to Reymers' former master, Lange. In this the writer states that Reymers, when Lange at his urgent request had consented to take him to Hveen, continued to poke and pry among Tycho's instruments and books whenever nobody was near, and to make drawings of everything; that one of Tycho's pupils warned his master about this, and mentioned it to a certain Andreas[67] who then went to sleep at night in the room with Reymers, and while the latter slept took a handful of papers out of one of his breeches-pockets, but was afraid to search the other for fear of waking him; that Reymers on discovering his loss behaved like a maniac, upon which he received back those of his papers which did not concern Tycho Brahe. The secretary also states that Reymers, after Lange's return to Bygholm Castle in Jutland continued to behave more and more like a madman, and told everybody that Lange was going to hang him, until his master got tired of all this and dismissed him.[68]

Though it could not possibly be proved that Reymers had copied the idea of his planetary system from Tycho Brahe, it must be conceded that the latter had good reasons for suspecting him, even before he published his system in 1588, and we must remember that the scientific men of the age were always afraid of being robbed of their discoveries, and often took great pains to secure priority by hiding them in anagrams. But on the other hand, Reymers certainly was an original thinker, and he may quite independently have come to the same idea which Tycho had already conceived. But the whole question is not of much consequence, and we have merely dwelt so long on it because it attracted a good deal of attention at the time, and because the steps which Tycho afterwards took against Reymers throw considerable light on his own character. Having spent the winter 1598–99 at Wittenberg, where his family had joined him, Tycho was further delayed by the illness of his eldest daughter; but shortly after Easter he at last set out for Prague, letting his family, however, stop for a while half way, at Dresden, until he had himself seen the state of things at Prague.

  1. In the account "De interruptione," &c. (Barrettus, p. 801), as well as in a letter to Vedel in 1599 (Weistritz, i. p. 171), Tycho says that the order not to observe on the rampart was given by Aulæ Magister (i.e., Valkendorf), though he had been one of the four protectors who had granted him the use of the tower in 1589. See also a letter to Vincenzio Pinelli of Padua (Aus T. Brahe's Briefwechsel, p. 12).
  2. Tycho says (Barrettus, p. 802): "Taceo nunc, quæ circa reprobos istos Insulares et Parochum in odium mei evenerunt" (compare footnote 3 on page 237). In a letter to Paschalius Mulæus (Glaus Mule, one of his pupils), of unknown date, but found among the MSS. of Longomontanus, Tycho says (after describing how he had lost his endowments and had been forbidden by the mayor to carry on his exercitia): "I shall also pass over what happened to my clergyman from hatred to me, also the insolence shown to me by those who were instigated to it, also that I was forbidden to take legal proceedings against them" (Bang's Samlinger, ii. p. 493; Weistritz, i. p. 155). Gassendi, p. 140, uses almost the same words, and has them probably from the same source.
  3. Friis, T. Brahe, p. 234, quoting from the original document in the archives at Copenhagen.
  4. Gassendi (p. 140) evidently knows very little beyond the allusion to the trip in the Elegy; he only knows the name of one of the emissaries, and misspells it Feuchius. He does not mention that any damage had been done to the instruments.
  5. See particularly pp. 77–78, and p. 292, rule 15. About this book, compare R. Wolf, Handbuch der Astronomie, pp. 173, 179, and Catalogue of Crawford Astr. Library, p. 188. Kästner (i. p. 629) does not seem to have perceived the valuable parts of the book. Fincke (1561–1656) was first physician to the Duke of Holstein-Gottorp, then Professor of Mathematics, and from 1603 of Medicine at the University of Copenhagen. He had studied at Strassburg and Padua, and corresponded for some years with Magini. According to Lalande and Poggendorff, he wrote previous to 1603 several tracts on astronomical subjects, but after 1603 he devoted himself only to medicine.
  6. This testimonial is printed by Gassendi, pp. 140–141. Tycho calls himself "Dominus hæreditarius de Knudstrup et arcis Uraniburgi in insula Dauiæ Venusia Fundator et Præses."
  7. Letter in Danske Magazin, ii. p. 325 (Weistritz, ii. p. 318).
  8. Ibid., p. 325. That Friis already had another prebend is stated by Tycho himself, ibid., p. 348 (Weistritz, ii. p. 346). Tycho says (Hist. Coel., p. 802, that he was "vix e patria egressus" when this happened. He must, therefore, have left Copenhagen between the 1st and 10th June.
  9. The original is printed in Danske Magazin, ii. pp. 327–330, translated in Weistritz, i. p. 122 et seq.
  10. Probably this was an embassy to Cöln an der Spree (Berlin) in connection with the approaching marriage of the king with Anna Catharina of Brandenburg.
  11. Danske Magazin, ii. 330 (Weistritz, ii. p. 322).
  12. These letters are printed in the Danske Magazin, ii. pp. 330–336 (Weistritz, ii. p. 323 et seq.).
  13. Several letters between Tycho and his kinsman Eske Bille (from the years 1599–1600) seem to show that Tycho had some dispute with several other heirs of his aunt. See Breve og Aktstykker, pp. 49 and 99.
  14. G. C. F. Lisch, Tycho Brahe und seine Verhältnisse zu Meklenburg, pp. 9–10 (Jahrbücher des Vereins für meklenburgische Geschichte, xxxiv.).
  15. See Tycho's letter to Vedel of September 1599 (Weistritz, i. p. 172).
  16. The Danish original in Danske Magazin, ii. p. 336 et seq., translated by Weistritz, i. p. 126 et seq.
  17. This refers to the fief of Nordfjord and the estate of the Roskilde prebend. The Island of Hveen could not be taken from him as he had got it for life, and we shall see that Tycho continued to keep a steward there, and received rent and produce from the island.
  18. Jöcher's Gelehrten Lexicon, vol. ii.
  19. De occasione interruptarum observationum et discessus mei. Historia Cœlestis, pp. 801–802.
  20. Ibid., p. 802, also in Resenii Inscript. Hafnienses (1668), p. 347, and in Casseburg, Tychonis Brahe relatio de statu suo, &c. Jena, 1730, less correctly given by Gassendi, p. 143.
  21. Ranzovianum Calendarium, printed at Hamburg in 1590, described by Kästner, ii. p. 413.
  22. "Qui alias talibus rebus non afficitur."
  23. "Quod et adhuc facere paratus sum." This copy of the poem (21/2 pp. folio) is now in the University Library at Leyden. See also Danske Magazin, i. 340 (Weistritz, ii. p. 334).
  24. "Dan ich darum keinen Verlangen trage, nunmehr vor mein Person in Dennemarck zu sein und gerestituiret zu werden, und wan das schon geshehen solte, so ist es mir doch sehr uiigelegen auf der Insel Huen lenger zu wohnen, und stets zu bleiben, wovon ich an einem anderen Ort meine Ursachen verzeichnet habe." I believe there is not any document extant in which these reasons for not living at Hveen are stated.
  25. Danske Magazin, ii. pp. 342–344 (Weistritz. ii. p. 336 et seq.).
  26. Danske Magazin, ii. pp. 344–349. "Die Vrsachen warumb Tycho Brahe sich aus Dennemarck in Teutschlandt begeben, kürtzlich zu vermelden, sein diese."
  27. He must mean exclusive of his annual income from the various endowments.
  28. About 300 hectolitres. In ready money Tycho, therefore, had 2400 daler (£533) a year, including the rent from the eleven farms at Kullen. See above, p. 235, footnote.
  29. Danske Magazin, ii. pp. 349–351 (Weistritz, ii. pp. 348 et seq.).
  30. Barretti Hist. Cœl., p. 822.
  31. In the letter to Magini (28th November 1598, Carteggto, p. 222, also p. 238), Tycho says that the middle of the eclipse at Uraniborg was observed at 11h. 5m. a.m., magn. of eclipse between 9 and 10 digits. In the letter to Kepler he wrote (Dec. 9, 1599, Opera, i. 225) that the observer at Hveen found by the large armillæ the beginning, end, and middle, in accordance with Tycho's tables. In his Optics Kepler made use of this observation, and gave the contacts as having occurred at 10.3 and 12.32 (Opera, ii. 367), but in the Tab. Rudolph., p. 110, he says that Origanus had observed 101/3 and 12.32, and that the figures given in the Optics must have been copied from Origanus, putting 10.3 for 101/3 (compare Opera, ii. 441). But if so, this is no fault of Tycho's, as he did not give any observed contacts. There is nothing about this observation in the Historia Cœlestis, nor could I find it in the original volume for 1596–97. Tycho does not mention the name of the observer at Hveen, only in the letter to Kepler he says the observation was made "a quodam istic relicto studioso."
  32. Letter from the Electress to Tycho of 14th February 1598. Danske Magazin, ii. p. 352 (Weistritz, ii. p. 353).
  33. Tychonis Brahe Astronomiæ Instauratæ Mechanica, in the centre the vignette "Suspiciendo despicio," underneath, "Wandesburgi, Anno CIƆ IƆ IIƆ. Cum Cæsaris et Regum quorundam Privilegiis." Colophon: Vignette Despiciendo suspicio, and under that: "Impressum Wandesburgi | in Arce Ranzoviana prope Hamburgum sita, | propria Authoris typographia | opera Philippi de Ohr Chalcographi | Hamburgensis | Ineunte Anno mdiic." This original edition now only exists in a few great libraries. In the Royal Library of Copenhagen are two copies with all the pictures beautifully illuminated and gilt, the one presented to Grand Duke Ferdinand de Medici, the other to the Bohemian nobleman "Peter Vok Ursinus, Dominus a Rosenberg;" in the Strahöfer Stiftsbibliothek at Prague is one presented to Baron Hasenburg (Astr. Nachr., iii. p. 256); in the British Museum is a copy presented to Hagecius, &c. On the front cover of these presentation copies is Tycho's portrait stamped in gold, with the inscription round it:

    "Hic patet exterior Tychonis forma Brahei,
      Pulchrius eniteat, qvæ latet interior."

    The back shows his coat of arms (a golden pale on azure ground), with the distich round it:

    "Arma, genus, fundi pereunt, Durabile virtus
      Et doctrina decus nobilitatis habent."

  34. Astr. inst. Mech, fol. A. 6, and fol. D. verso.
  35. He divides his observations into "pueriles et dubitæ" (at Leipzig), "juveniles et mediocriter se habentes" (up to 1574), and "viriles, ratæ et certissimæ " (from 1576).
  36. See above pp. 213 and 223.
  37. The figures in our Chapter V. are reduced copies of Tycho's figures. The principal contents of the Mechanica are given in the introduction to Flamsteed's Hist. Cœl. Brit., vol. iii., and the figures of the instruments are copied in the Mémoires de l'Académie for 1763.
  38. In the first issue of the Progymnasmata (1602) there is quite a different portrait, not resembling any other, but standing in the same arch. In Hofman's Portraits historiques there is another engraving by Haas of Copenhagen, apparently a copy (reversed) of Geyn's, which is reproduced in Weistritz's book.
  39. There is a copy of this portrait in Friis' book, Tyge Brahe (1871).
  40. The first line ("I am protected, standing on solid ground, let wind, fire, and waves rage") is evidently intended to express Tycho's trust in the future, notwithstanding the threatening aspect of the time. Ot. means Ottonides. The inscription is given in Resenii Inscriptiones Hafnienses, p. 335, Weistritz ii. p. 334, and identifies the picture.
  41. It was first noticed by Dr. S. Crompton (Proc. Manchester Lit. and Ph. Soc., vol. vi., 1876), and was in 1881 purchased by the Earl of Crawford, who in 1888 presented it with his great astronomical library and all his instruments to the Royal Observatory, Edinburgh. See frontispiece.
  42. Vierteljahrsschrift der astron. Gesellschaft, xvi. p. 273 (1881), Safarik.
  43. The three first-mentioned tables are printed in the Progymnasmata.
  44. This introduction is printed by Gassendi, pp. 247–256.
  45. Printed in Breve og Aktstykker, p. 31 (from two draughts in the University Library at Basle).
  46. This is the copy which afterwards came into the possession of Gassendi, who gives (pp. 257–259) a list of remarkable discrepancies between star-places in it and in the Tab. Rudolph.
  47. Astron. Jahrbuch fur 1786, p. 216.
  48. This copy is now in the University Library at Leyden ("Descriptio stellarum octavi orbis inerrantium "). There is a copy of the catalogue in the Bodleian Library, presented to a Venetian nobleman.
  49. As suggested by Baily in his reprint of the catalogue, Mem. R. Astron. Soc., xiii.; compare his Account of the Rev. J. Flamsteed, p. 368.
  50. Now in the Royal Library, Copenhagen. In a letter from Henrik Ramel to Sophia Brahe (of 20th September 1599) the former writes that he would have sent her the books, but had to ask the king first, and his Majesty had said that though he did not understand or care much about them, still he would keep them as they were presented to him by Tycho Brahe (Breve og Aktstykker, p. 39). These books were possibly the Mechanica and the Catalogue of Stars.
  51. Breve og Aktstykkcr, p. 34.
  52. This letter is printed in the Danske Magazin, 3rd Series, iii. pp. 79–80.
  53. Martini Everarti Ephemerides novæ et exactæ 1590–1610 ex novis tabulis Belgicis. Lugduni Batav., 1597.
  54. In the Museum of Northern Antiquities at Copenhagen there is a watch which is said to have been presented to Tycho Brahe by Rantzov. It is oval in shape, has two dials, one for hours and one for minutes, and Tycho's name, arms, and the motto, "Qvo fata me trahunt, A.D. 1597," are engraved on the inner case. In the same museum is a wooden easy-chair which is supposed to have belonged to T. Brahe.
  55. Gassendi, pp. 156–157. In return for these books, Scaliger some months later sent Tycho a copy of his Conjecturæ et notæ in Varronem, which Tycho gave or lent to Taubmann, Professor of Poetry at Wittenberg. Kästner, Gesch. d. Math., ii. p. 409.
  56. Letter (in the archives at Schwerin) printed in Friis, Tyge Brahe, p. 319.
  57. Carteggio inedito di Magini, pp. 217 and 230. Baldi's Delle Vite de' Matematici was never published (Kästner, ii. 140).
  58. He observed the meridian altitude of the sun on the 9th December at Wittenberg.
  59. Mulleri Cimbria literata, vol. ii. p. 105.
  60. He afterwards abandoned this idea, because the eclipse of January 31, 1599, did not agree with his theory, although he had expected that it should agree as well as that of January 1582, as they both took place near the apogee and at the same time of year. (Letter to Longomontanus of 21st March 1699, Gassendi, p. 159). This shows that he had at that time an idea of the existence of the annual equation. (See next chapter.)
  61. We have already mentioned (p. 209) that this refutation was never published. It appears from a letter to Scultetus, written in January 1600, that Tycho was still thinking of adding an appendix to the book on comets.
  62. Gassendi, pp. 158, 159.
  63. "Nicolai Raimari Vrsi Dithmarsi S. Cæs. Maj. Mathematici de astronomicis hypothesibus seu systemate mundano tractatus astronomicus et cosmographicus scitu cum iucundus tum vtilissimus. Item astronomicarum hypothesium a se inuentarum, oblatarum et editarum contra quosdam eas sibi temerario vel potius nefario ausu arrogantes, vendicatio et defensio. . . . Pragæ Bohemorum apud auctorem. Absque omni priuilegio. Anno 1597." 78 pp., 4to. Kästner, iii. p. 469. Delambre, Astr. mod., i. p. 294. I have not seen this book myself.
  64. Helisæus Rœslinus in 1597 published a book, De opere Dei Creatoris, in which he stated that he had independently found the same system as Tycho Brahe, and in a later publication he stated in detail how he did this after reading Ursus' book of 1588. (See Frisch in vol. i. p. 228 of his edition of Kepleri Opera.)
  65. Reymers writes this in broken Danish: "Den Tyske Karle er allsammell all gall" (should be: "de Tydske Karle ere allesammen halv gale").
  66. See above, p. 183.
  67. Perhaps No. 5 on the list of pupils (Note B.).
  68. This document is printed in Kepleri Opera, i. p. 230.