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




It was perhaps well for Tycho Brahe that his career in Bohemia was cut short, for he would sooner or later have been bitterly disappointed in the faith he had placed in the Emperor's promises. His greatest wish had always been that the observatory work should not cease at his death, but that some competent person might be appointed to carry it on; but though Kepler, two days after Tycho's death, was informed by Barwitz that he was to be the new Imperial mathematician, the observations with Tycho's instru- ments were not continued very long. The Emperor soon agreed with Tycho's family to purchase the instruments for the sum of 20,000 thaler; but when Tengnagel came back to Prague in the summer of 1602, he assumed the position of Tycho's scientific heir, promised the Emperor to have the Rudolphine tables finished within four years, and though Kepler had commenced to observe Mars, he was deprived of the instruments, which were stored away in a vault under Curtius' house. Kepler never got access to them again, of which he complains repeatedly in his writings.[1] They seem to have been preserved in this manner until the year 1619, when the Bohemians rose against the House of Habsburg and elected Frederic V., Elector Palatine, their king, and during the disturbances which followed, some of the rebels are said to have destroyed the instruments as Imperial property.[2] The great globe alone was saved, and was in 1632 found at Neisse, in Silesia, at the College of the Jesuits, by Prince Ulrik, a son of King Christian IV. of Denmark, who was in the service of the Elector of Saxony, and had taken Neisse by storm. How or when the globe had been sent there is not known, but Prince Ulrik now sent it to Denmark, where it was first kept at the Castle of Rosenborg, then at the University,[3] and afterwards in a room of the Round Tower which had been erected in Copenhagen to serve as a University observatory, and was finished in 1656. An inscription, composed by Longomontanus, was attached to the globe or to the wall of the room, and the beautiful monument of the great astronomer remained at the Round Tower till October 1728, when it was unfortunately destroyed in the great conflagration, in which, among many other things, Ole Römer's unpublished observations perished. At the present day there is neither at Prague nor at Copenhagen the smallest vestige of Tycho's celebrated instruments.[4]

Tycho's wife and children all remained in Bohemia, probably because they were honoured and respected there, while the difficulty which they found in obtaining payment for the instruments must also have tied them to Bohemia, as they must have known well that they would have no chance of getting their money unless they remained on the spot. Tycho's widow died in 1604, and was buried beside her husband, as we have already mentioned. A year or two before her death she had purchased a country property towards the Saxon frontier, and her eldest son, Tycho, had in March 1604 married the widow of a country gentleman in the same neighbourhood. He became the father of five children, and died in 1627. His younger brother Jörgen (George), died in 1640. Magdalene Brahe, Tycho's eldest daughter, apparently never married; of the second daughter, Sophia, nothing is known except that she became a Roman Catholic. The youngest daughter, Cecily, married a Swede, Baron Gustaff Sparre, colonel of a German regiment, and died at Krakau. In 1630 some of Tycho Brahe's nearest relations in Denmark, among whom was his sister Sophia, issued a declaration, stating that Christine, by the ancient laws of the kingdom, "on account of the open, unchanged, and honourable life of both of them, must be acknowledged as his wedded wife."[5]

Tengnagel very soon gave up the idea of working at the Rudolphine tables. He had probably only been a short time at Uraniborg (he is mentioned as an unpractised observer in September 1595), and there are no signs of his having occupied himself seriously with astronomy during Tycho's lifetime, so that probably it was only jealousy of Kepler which induced him to prevent the latter from taking up Tycho's work at once. He was in 1605, by the Emperor, made a Councillor of Appeal, and received a grant from the Benatky estate "for his astronomical observations," and he was also employed on various foreign embassies among others, to England, whither he was accompanied by Eriksen, who also gave up astronomy.[6] Tengnagel was appointed Councillor to Rudolph's cousin, Leopold, Bishop of Passau, and afterwards became a privy Councillor to Ferdinand II. He was the only one of the family who was allowed to remain in Bohemia after the battle of Prague (November 1620), when the Protestants were driven from the Austrian possessions. His wife, Elizabeth Brahe, had died in 1613, leaving several children. He died in 1622.

Notwithstanding his connection with the two Emperors, Tengnagel had been unable to get the purchase-money for the instruments paid in full. From a letter which Magdalene Brahe wrote to Eske Bille in July 1602 we learn that, although the Emperor soon after Tycho's death had agreed to purchase the instruments for 20,000 thaler, he was, as usual, without money, and had in vain tried to get the Bohemian Estates to pay the sum, which they declined to do, on the plea that this was a private matter of the Emperor's; and he attempted to persuade the heirs to accept some more or less doubtful securities instead of ready money.[7] This, however, they would not do, and in September 1603 they got 4000 thaler paid from the royal revenues. Owing to the disturbed state of Bohemia and the subsequent great war, the family apparently never received any part of the remaining 15,000 thaler, though they persevered for many years in their applications to the Government. The last time anything bearing on this matter is mentioned is in 1652, when it is stated that a married daughter of the younger Tycho had been six years in Bohemia on a safeguard from the Elector of Saxony, endeavouring to get her share of the money due from the Treasury.[8]

The first piece of work which Kepler undertook after Tycho's death was to get the Progymnasmata published. The section about the lunar theory was not yet printed, but the woodcuts were ready and the text completed in manuscript. A postscript seemed desirable, explaining how the book had been written and printed by degrees, and Kepler at once wrote this appendix, which fills six pages.[9] He first explains how Tycho's anxiety that the book should contain the latest results of his investigations had made him push on with the printing before the whole manuscript was ready (it had been prepared in the years 1582–92). A few slight discrepancies are pointed out between these latest results and a few passages in the book, concerning the moon, but printed long before. It is also remarked that in the first chapter the planetary inequalities are referred to the sun's mean place, while it had recently been found in the case of the moon and Mars that it is the apparent place which enters into the equations, so that the same doubtless also was the case with the other planets. Lastly, the recently noticed fact that the solar excentricity is only half as great as formerly believed, is referred to. A dedication to the Emperor from Tycho's heirs, a short notice to the reader (stating that the author had intended to write a preface on the utility and dignity of astronomy), and the privileges of the Emperor and James VI. were also printed, and the book was published in the autumn of 1602. The title is: "Tychonis Brahe Dani Astronomiæ instauratæ Progymnasmata. Quorum hæc Prima Pars de restitutione motuum Solis & Lunæ, Stellarumque inerrantium tractat. Et præterea de admiranda noua Stella Anno 1572 exorta luculenter agit. Typis inchoata Vraniburgi Daniæ, absoluta Pragæ Bohemiæ MDCII" (some copies have MDCIII). The book seems to have been printed in 1500 copies,[10] and most of these appear to have been afterwards sold to Gottfried Tampach, a well-known bookseller in Frankfurt, who, in 1610, issued the book with a new title-page and the beginning as far as p. 16 reprinted.[11]

The second volume of the Progymnasmata had, as we have seen, been quite ready since 1588, though Tycho had only presented a few copies to correspondents, and had intended to add an appendix on Craig's allegations about the parallax of comets. This he had never done, and the book was now published in 1603 with a new title-page, and a dedication to Barwitz from Tengnagel, as well as a preface to the reader.[12] Like the first volume, it was re-issued by Tampach in 1610 with a new title-page, and the first seven leaves (including Tycho's own preface) and the two last pages reprinted.[13] The issue of 1610 is generally found bound together with the first (and only) volume of the Epistolæ, printed in 1596, furnished with a new title-page, but retaining the original colophon. Tampach had probably acquired the stock of copies of the Epistolæ on the death of Levin Hulsius of Nürnberg, a well-known writer and publisher, to whom the heirs would seem to have sold them, as some copies have on the title-page: "Noribergæ, apud Levinum Hulsium MDCI."

The stock of copies of the Astronomiæ instauratæ Mechanica appears to have been exhausted, but most of the wood- cuts and copper-plates were in the possession of the heirs, who sold them to Levin Hulsius. He printed a new edition at Nürnberg in 1602, exactly like the original, but with narrower margins, and without the neat border which in the original runs round the pages. Paper and print are also somewhat inferior, and Tycho's portrait is on the title- page substituted for the vignette of the original.

On the state of Tycho's other manuscripts Kepler drew up a short report,[14] from which it appears that the printing of the second volume of letters had been commenced, and that Tycho had thought of adding some astronomical tables to the volume to make it more saleable. Kepler suggested that matter of astronomical interest occurring in the un- printed letters might be extracted and printed, so that the sheets already in print would not be wasted. This was, however, not done, and only a few of the letters have yet been published. For the third volume of Progymnasmata (on the comets of 1582, 1585, &c.), the materials were ready, but nothing was put into shape. As to the Tabulæ Rodolpheæ, Kepler stated that the materials were abundant, "nec deerunt ingenia, si Maecenates sint, et exiguum aliquid in certis pensionibus annuis in hunc usum erogetur." The Theatrum astronomicum (of which Tycho had sketched the plan in his letter to Peucer in 1588[15]) should contain the theory on which the tables were based, but nothing of it had been written.

It seems that Kepler received Tycho's observations, originals and copies, after signing a contract with Tengnagel in 1604. He found them so indispensable to his studies that he never returned them, but it was not forgotten that they were in his possession, and in November 1621 (when he had been obliged to stay more than a year in Würtemberg to watch the trial of his mother for witchcraft) Ferdinand II wrote to the Duke of Würtemberg requesting him to command Kepler to return the manuscripts.[16] Kepler was probably back again at Linz (where he had lived since 1612) when the letter arrived in Würtemberg, and it had no effect. After publishing the Tabulæ Rudolphinæ in 1627, he thought the following year, while living at Sagan, in Silesia, under Wallenstein's patronage, of getting the observations printed. He wrote on the 17th August 1628 to Jörgen Brahe that he hoped soon to commence the printing, but as he had found a selection from the observations of the years 1600 and 1601 inserted in Snellius' edition of the Landgrave's observations,[17] he inquired if Brahe still had the originals for those two years, or whether Snellius could have got hold of them, so that his widow might have them still.[18] Nothing came, however, of the intended edition, and the original observations remained in Kepler's possession, and after his death in that of his son, the physician, Ludwig Kepler.[19]

But while Kepler retained the originals as pledges for the considerable arrears of salary due to him, a set of unfinished copies in quarto volumes had remained in Austria.[20] These volumes are alluded to by Tycho Brahe in his Mechanica (fol. G. 2), where he mentions that the observations had been entered in large volumes, and afterwards, for each year, copied into separate volumes and sorted according to subject—the sun, moon, planets (beginning with Saturn and ending with Mercury), and the fixed stars. Albert Curtz, a Jesuit, and Rector of the College of Dillingen, on the Danube, who had corresponded with Kepler both on scientific and religious subjects, conceived the idea of publishing Tycho's observtions from these volumes. It is very strange that he should not have made any serious effort to obtain the originals, as he was engaged on the work already before 1647, in which year Gassendi heard of the undertaking; while Hevelius in the following year inquired how the rumour could be true that a Jesuit had got Tycho's observations from the Emperor and was about to publish them, since Hevelius with his own eyes had seen the original observations from 1564 to 1601 in Ludwig Kepler's house at Königsberg. Curtz himself seems, however, to have believed that the nineteen annual volumes for the years 1582–92 and 1594–1601, which he had before him, were originals and not copies, and though he suggests that they were the set of twenty-one volumes referred to by Tycho in the Appendix to the Mechanica (fol. H. 4), it does not seem to have occurred to him that in that case not only the volume for 1593, but five earlier volumes must have been lost, since Tycho wrote the Mechanica in 1597. The volumes which he used, and which he describes as being ornamented on the cover with Tycho's portrait and arms,[21] were therefore copied, and the observations of 1582 printed in 1656 as a specimen,[22] after which the complete Historia Cœlestis was published at Augsburg in 1666 in a handsome thick folio volume, on which the editor, instead of his own name, Albertus Curtius, has called himself anagram-matically Lucius Barrettus.[23]

The various astronomical observations, chiefly of eclipses anterior to Tycho's time, as well as the observations of the Landgrave, Mästlin, and others, which Curtz inserted in this volume, are not without value and interest, but Tycho Brahe's observations are presented in so mutilated and distorted a shape as to be well-nigh useless. Not only is there no explanation why the volume begins with the year 1582 (which has led many writers to believe that Tycho had not observed regularly until then), but it is evident that the copy at the disposal of Curtz had never been finished nor collated with the originals. Frequently several consecutive pages have been passed over, so that the volume is very far from containing a complete record even for the years it pretends to cover. For instance, at the end of 1584, half the observations made by Elias at Frauenburg and all those he made at Königsberg are omitted. Again, in 1589 and 1591 there are several large gaps in the observations of fixed stars, similarly in 1595 and 1597, while the omissions of one or two nights' work are very numerous indeed. But this is far from being the worst fault. There is scarcely a column which is not full of errors, figures misplaced or left out, words like dexter and sinister, borealis and meridionalis, are interchanged; sometimes the signs of the zodiac have even been mistaken for figures, so that the sign of Cancer becomes 69, &c. In short, the work is not far from being an Augean stable. Unfortunately there is no other edition of Tycho Brahe's observations except of the observations of planets made in 1593[24] and of the observations of comets. The Historia Cœlestis gives the reader a fair idea of the general scope of Tycho's work, but it cannot be used for any scientific purpose.

In the meantime the original observations, of the existence of which Curtz was ignorant, were (at the latest in the beginning of 1662) by Ludwig Kepler sold to King Frederick III. of Denmark, who deposited them in the newly founded Royal Library at Copenhagen, where they are still preserved. King Frederick soon after decided to have them published under the direction of the mathematician Professor Erasmus Bartholin, under whom six students were employed in copying and collating, while the necessary pecuniary means were liberally supplied. A complete copy had been made and carefully read with the originals, when Bartholin heard of the publication of the Historia Cœlestis, and obtained a copy of it. As he found it extremely defective and erroneous, he published in 1668 a critique of it, showing the errors in the observations of 1582, and announcing the forthcoming correct edition.[25] Bartholin furthermore compared a copy of the Historia Cœlestis (bound in two volumes) with the originals, and entered in it all the corrections and smaller omissions, while he in a third volume had the observations previous to 1582, the longer omissions, the year 1593, and the observations of comets, carefully copied and compared with the originals.[26] In 1669 he caused inquiries to be made from Blaev, in Amsterdam, about the printing of the new edition, which Blaev seemed disposed to undertake.[27]

Unfortunately, King Frederick III. died in 1670, and as his son and successor took no interest in literature or science, there was an end to the prospect of a correct edition of Tycho Brahe's observations. In the following year Picard came to Copenhagen to determine the geographical position of Uraniborg, and on learning how matters stood, he begged and obtained leave to take Bartholin's copy back with him to Paris to have it printed at the expense of Louis XIV.[28] For the sake of control during the printing, the originals were handed to Bartholin's assistant, Ole Römer, whom Picard had persuaded to go with him to France. The printing was commenced at Paris, but Louis XIV.'s wars required money, and the undertaking was eventually stopped.[29]Inquiries were made for the original manuscripts by the Danish Government in 1696, and they were found in charge of La Hire at the Paris Observatory.[30] They were handed over to the Danish envoy in 1697, but were not sent back to Copenhagen till his return to Denmark in 1707. Being deposited in the Royal Library, they fortunately escaped the great fire of 1728, in which the University Library and the Observatory (with Römer's observations) were destroyed. In 1707 it was suggested by Dr. Arbuthnot, physician to Prince George of Denmark, that Tycho's observations ought to be printed in England, together with those of Flamsteed, and Newton drew up a letter to Römer on the subject, but nothing further came of it.[31] Bartholin's copy remained in Paris at the Académie des Sciences, and is now at the Paris Observatory.[32] La Hire had copied the observations of 1593 from the originals, and they were published in the Mémoires de l'Académie for 1757 and 1763. De l'Isle had made a copy of the whole series, translated into French, but with frequent omissions, which is now also deposited at the Paris Observatory. Pingré made extensive use of it for his Cométographie.[33]

While Tycho's observations were thus turned to lasting account, there is scarcely a trace left of the magnificent buildings he raised at Hveen.

"Est in conspectu Tenedos, notissima fama,
Insula dives opum, Priami dum regna manebant,
Nunc tautum sinus et statio male fida carinis."

It would almost seem that Tycho did not build in a very substantial manner, for already in 1599 Eske Bille wrote to him that the farm buildings would soon tumble down, and that the forge was also in a very bad state, for which reason the clergyman wanted to know whether he might use the materials to repair the rectory, which already some years before had fallen into disrepair. Tycho answered that the clergyman had no claims on him, and had behaved very badly, and the peasants had been stealing building materials from the rectory. "As to the farm and the castle itself being in bad repair, I can only say, as I have done before, that I do not intend to go to any further expense about it; there was far too much spent on it before, and if I had the money back, it should hardly be so badly spent."[34]

Soon after Tycho's death, in May 1602, Cort Barleben received Hveen in fief, and shortly afterwards he was granted permission to pull down the forge. His successor was a mistress of the king's, Karen Andersdatter, who got the island in 1616, and was followed by her son, Hans Ulrik Gyldenlöve, who died in 1645, and seems to have been succeeded by some nobleman's widow. The destruction of Uraniborg had in the meantime gradually proceeded, as there was nobody to look after it. A new dwelling-house was erected on the site of Tycho's farm, called Kongsgaarden, which stood for about two hundred years, but has now dis- appeared, so that only some farm buildings remain. This Kongsgaard was built of the bricks and stones of Uraniborg, as a mason in 1623 was paid for 60,OOO bricks which he had "pulled down and renovated from the old castle Oranienborg."[35] In 1645 Jörgen Brahe, a nephew of Tycho's, was granted permission to remove "any stones with inscriptions or other carved figures or characters " which might be found at Hveen.[36] Perhaps Tycho's nephew was anxious to secure some slight relic of his uncle before it was too late, for a couple of years later, when Gassendi inquired about the island, he was informed that there was only a field where Uraniborg had been.

In 1652 the island was for the first time after 1597 visited by a man of distinction. Pierre Daniel Huet, afterwards so well known as the editor of the classics "in usum Delphini," and sometime Bishop of Auranches in Normandy, was a young man of twenty-two when, in 1652, he accompanied the learned Bochart, who had been invited by Queen Christina to join the galaxy of learned foreigners at Stockholm. Passing through Copenhagen, Huet paid a visit to Hveen, and found scarcely a trace of the buildings. In his autobiography, which he did not draw up till more than sixty years later, when he says himself that both his senses and his memory were impaired after a serious illness, Huet adds the very absurd statement that neither the clergyman nor the other inhabitants of Hveen had ever heard the name of Tycho Brahe, except one old man, who did not give a flattering account of him. Successive writers down to the present day have quoted this story without noticing the absurdity of the idea that a small community of a few hundred people should in the course of fifty years have quite forgotten the man who raised such fine and singular buildings and was visited by kings and princes.[37]

A few years after, Hveen ceased to belong to Denmark. In February 1658 the Danish king was forced to conclude the humiliating treaty of Roskilde, by which the provinces east of the Sound, which from before the dawn of history had been Danish, were handed over to Sweden. King Carl Gustav, who was not content with what he had got, but soon after made an ineffectual attempt to take the whole of Denmark, claimed Hveen as belonging to Scania, because the inhabitants were now under the jurisdiction of the court of Lund.[38] The spot where Tycho had lived and worked was thus torn from the country which had so little valued him, and, like Scania, the island soon became perfectly Swedish—a very natural consequence of the close affinity between the two nations, rivals for so many centuries, but now animated only by brotherly feelings.

In 1671 the Académie des Sciences sent Picard to Hveen to determine the geographical position of Uraniborg. The foundations were still easily recognised, and the earthen walls round Uraniborg untouched, except that a stone wall had been built across the enclosure, cutting off the north-eastern wall and a little of the two adjoining ones, and the parts thus cut off had been nearly obliterated by ploughing. Of Stjerneborg he saw nothing except a slight hollow in the ground, and he did not trouble himself about making excavations.[39] During the eighteenth century the ruins were occasionally mentioned by travellers, but nobody seems to have explored them.[40] About 1740 a stone with a Latin inscription was removed from the site of Tycho's paper-mill to his old home at Knudstrup, from whence it was later brought to the museum at Lund. In 1747 a cellar was accidentally found on the site of the servants' dwelling, at the north angle of the wall enclosing Uraniborg. It is still to be seen, and if the statement on Braun's map be correct, that it was used as a gaol, it can certainly not have been a pleasant abode, though doubtless not worse than other dungeons of those days.

Within the present century the ruins at Hveen have been more thoroughly examined. They suffered a further desecration about eighty years ago, when the south-western enclosure wall round Uraniborg was broken through, in order to build a schoolhouse there. The Swedish antiquary Sjöborg visited the island in 1814, but was chiefly inte- rested in the various slight antiquities from long before Tycho's time.[41] But in 1823 and 1824 the clergyman of Hveen, Ekdahl, examined the interesting spots carefully. At Uraniborg he found the deep well, which was easily cleaned out, and still gives excellent water; also some water-taps and pipes from the hydraulic works which had sent the water to various parts of the house. Parts of the foundation walls and some slight remains of the laboratory were also unearthed. At Stjerneborg Ekdahl was more successful, and found distinct traces of all the crypts, and one of them (F. on the plan, p. 106) in perfect preservation, with all the circular steps, and the low column in the middle, on which the large quadrant had formerly been fixed. The only ornament or inscription found was the stone with the words also put on Tycho's tomb: "Nec fasces nec opes, sola artis sceptra perennant;" so strikingly illustrated by the state of Tycho's works on earth and his labours in science.[42] Low stone walls form oval enclosures round the sites of Uraniborg and Stjerneborg, but otherwise the scanty remains of the buildings are quite unprotected, and will soon entirely disappear, being exposed to wind and weather. It is therefore well that they have been carefully described, first by the Danish poet, J. L. Heiberg, in 1845,[43] and by the distinguished astronomer D' Arrest in 1868,[44] both enthusiastic lovers of the memory of Tycho Brahe.

  1. Opera, ii. p. 760 (in the dedication to Hoffmann of the book on the star in Cygnus), and p. 755. In the book on the star in Serpentarius (ibid., ii. 656) Kepler quotes a few observations by Tengnagel, "in viridario Cæsaris, ubi deposita habebantur instrumenta Braheana." Perhaps they had then (October 1604) been brought back to Ferdinand I.'s villa. In December 1601 and May 1603 Kepler used one of Tycho's clocks in observing two lunar eclipses (Opera, ii. P. 300).
  2. Gassendi, p. 216.
  3. Where Huet saw it in 1652 (Commentarius, p. 81).
  4. The inscription is given by Gassendi, p. 217; Weistritz, i. p. 217. At the Prague observatory (founded in 1751 in the Clementinum, far from Tycho Brahe's observatory) there are two sextants and a clock showing the Tychonic system, which are supposed to have belonged to Tycho Brahe; but they show no sign of Tycho's refined workmanship, and the two sextants (the larger of which is said to have been made for him in 1600 by Erasmus Habermel) have not his peculiar pinnules. There is no proof of their ever having belonged to Tycho Brahe (Astron. meteorol. und magn. Beobachtungen an der Sternwarte zu Prag im Jahre 1880, p. iv. ).
  5. The document was written in German, so that the children of Tycho could make use of it in Bohemia and Saxony, where they all lived. Danske Magazin, ii. p. 367; Weistritz, ii. p 375. Sophia Brahe died in 1643 at the age of eighty-seven. She was the only one of Tycho's brothers and sisters on whom some of his glory was reflected, and when she, nine years before her death, at Elsinore, met a French embassy, the secretary, Charles Oger, in the description which he afterwards wrote of his journey, mentioned the meeting with her among the most remarkable events.
  6. Eriksen observed the solar eclipse of October 1605 in London, and brought letters backwards and forwards between Kepler and Harriot. He had early in 1602 (with Tengnagel) visited Fabricius in Ostfriesland, and afterwards for some time assisted Kepler (Opera, iii. 533, ii. 432).
  7. Danske Magazin, ii. p. 361 et seq.; Weistritz, ii. p. 369 et seq. From this letter it appears that the family had previous to July 1602 left Curtius' house, and lived in the part of the city called Altstadt. They had commenced to remove the instruments to their new residence, as they had not yet received any payment; and even of Tycho's salary, which the Emperor had ordered to be paid up to the date of his death only, there were still a thousand florins owing to them. In April 1608 Magdalene wrote a letter to Longomontanus (ibid.) giving him information about the family.
  8. For full particulars about these transactions see the paper by Dvorsky, quoted above, p. 307.
  9. That Kepler is the author of this appendix is stated by himself in a letter to Magini (Opera, iii. p. 495; Carteggio, p. 331); it is reprinted in Opera, vi. p. 568.
  10. Tycho inquired in January 1600 if he could get the sheets yet wanting printed at Görlitz in 1500 copies. Aus T. Brahe's Briefwechsel, p. 16.
  11. The misprints so far are corrected by the list of errata at the end of the book.
  12. The title is the same as given above on p. 163, except that instead of the last sentence it has: "Typis inchoatus Vraniburgi Daniæ, absolutus Pragæ Bohemiæ." The colophon is the vignette "Despiciendo svspicio," and underneath: "Pragæ Bohemorum. Absolvebatur Typis Schumanianis. Anno Domini MDCIII."
  13. The two volumes were reprinted in Frankfurt in 1648 with the title T. Brahei Opera Omuia. This is a very poor edition with very small print.
  14. Kepleri Opera, i. p. 191.
  15. See above p. 182.
  16. Breve og Aktstykker, p. 150.
  17. "Coeli et siderum in eo errantium observationes Hassiacæ . . . et specilegium biennale ex observationibus Bohemicis V. N. Tychonis Brahe." Lugd. Batav., 1618, 4to. Snellius had as a youth of twenty paid a short visit to Prague in 1599 or 1600. See R. Wolf's Astr. Mitth., lxxii.
  18. Breve og Aktstykker, p. 152. About Kepler's intention of publishing the observations, see his Opera, vi. pp. 616, 621, vii. p. 215 (in his book T. Brahei Hyperaspistes, Frankfurt, 1625, against Scipione Chiaramonte, who in his book Antitycho had tried to prove from Tycho's own works that comets are sublunary), also viii. p. 910. Gassendi, p. 207.
  19. On the outside of the cover of the volume for 1596–97 (bound in old music-paper) there is pasted a slip of paper on which Kepler has written: "Extract aus mein Johan Kepplers den Brahischen Erben zugestelter Erklerungsschrift. Entlich und zum fünften sol auf einem jedem Tomum herabgemeldeten Observationen, sobalt ich nach Linz komme ein offene Zettel auffgeleimet, und meinen Erben, darinnen von mir anbefohlen werden, dass solche Bücher, da ich etwa Todtes verbliche, absobalden zu meinem Schatz oder Kleinodien eingesperret und vor der Eröffnung Jhr. Kay. May. so wie auch denen Brahischen Erben, umb weitere Vorsorg und Verwahrung deroselben angemeldet werden, damit also die Erben auch auff diesem Fall, de abgesetzten ersten Puncts halben desto mehr versichert sein."
  20. Or perhaps they were purchased from Kepler's daughter, if the MS. account printed by Kästner is authentic (Geschichte d. Math., ii. p. 651 et seq.).
  21. Like the presentation copies of the Mechanica (above, p. 261). The nineteen volumes are still in the Hofbibliothek at Vienna, where there is also a miscellaneous collection of loose leaves or small stitched books with computations, notes, or letters. Some of the letters have been published of late years (Tychonis Brahei et ad eum doct. vir. Epist.). A list of the MSS. was made by Friis in 1868, but owing to his complete ignorance of the subjects referred to in them, it is of little use (Danske Samlinger, iv., 1869, p. 250).
  22. "Sylloge Ferdinandea sive collectanea historiæ coelestis ex commentariis MS. obss. Tychonis Brahei ab anno 1582 ad annum 1601. Accessit epimetron ex obs. Hassiacis, Wirtenbergicis et aliis . . . vulgavit Lucius Barrettus, anno ciɔ ɔic lvi Viennæ Austriæ." Contains the preface and Liber prolegomenus and the observations of 1582, headed on every page: "Sylloge Ferdinandea." Different print from the Hist. Cœl. At the end of the volume is the colophon: "Operis Davidis Havtii, Bibl. Viennensis, anno 1657."
  23. "Historia Coelestis complectens Observationes astronomicas varias ad Historiam Coelestem spectantes Ill. viri Tychonis Brahe, Babylonicas, Græcas, Alexandrinas, Moestlini observationes Tubingenses, Hassiacas, &c. Aug. Vind. 1666" (also with title-page on which "Ratisbonæ, 1672"). Large plate with four emperors, more or less imaginary views of Uraniborg, Wandesburg, Benatky, Horti Cæsaris and Domus Curtii, most of Tycho Brahe's instruments, &c. cxxiv. + 977 pp. fol.
  24. To account for the absence of these, Curtz invented a fable about the volume for 1593 having been sent to Cassel and thereby lost, which has been repeated by many writers.
  25. "Specimen recognitionis nuper editarum observationum astronomicarum n. v. Tychonis Brahe, in quo recensentur insignes maxime errores in editione Augustana Historiæ Cœlestis a. 1582 ex collatione cum autographo . . . ani- madversi ab Erasmo Bartholino." Hafniæ, 1668, small 4to, 48 pp., of which 6 pp. are dedication to the King, 11 pp. introduction, and the remainder errata. Reviewed by Kästner, ii. p. 656.
  26. Strange enough, he did not copy the year 1581, but instead of it the year 1583, though this is in the Hist. Cœl. About this supplement, see Bugge, Observations astronomicæ, 1781–83, Hafniæ, 1784, p. xviii., where a catalogue of Tycho's original MSS. is given. See also below, Note H.
  27. Werlauff, Historiske Efterretninger om det store Kongelige Bibliothek, Kjöbenhavn, 1844, P. 411.
  28. Picard gave the following receipt for them (copied by Bartholin into the supplementary volume): "Je confesse avoir recue de Mons. Erasme Bartholin les observations de Tycho Brahe escrites au net en cinq Volumes in folio depuis l'année 1563 jusques à 1601 avec les Observations des Cometes, à condition qu'ils seront imprimiées à Paris au Louvre aux depens du Roy de France, & quant a la Dedication & Preface elles seront faites par le dit Mr. Bartholin. Je promets aussy, qu'incontinent après l'ouvrage achevé d'imprimer, il en sera fourny cinquante exemplaires, qui seront mis entre les mains de qui l'on voudra. Fait à Copenhague, le 2 Avril 1672. Picard."
  29. Sixty-eight pages were printed (as far as 1582). See Lalande's Astronomie (2nd edit.), i. p. 198.
  30. Dänische Bibliotkek, viii. p. 684; Werlauff, l. c., p. 57; Observations septem Cometarum (1867), p. iii.
  31. Brewster's Memoirs of Sir I. Newton, ii. p. 168.
  32. M. Bossert of the Paris Observatory informs me that this copy is in six volumes (which agrees with Picard's receipt), in 4to, carefully written, the observations of comets being by themselves. The title is: Tychonis Brahe Thesaurus obscrvationum astronomicarum.
  33. Pingré, i. p. 517; Lalande, i. p. 199.
  34. Breve og Aktstykker, pp. 53 and 104.
  35. Vandalism of that kind is not confined to any age or nation, but the destruction of many a fine old monastery or chapel in the heat of the Reformation had made people at that time particularly callous to the pulling down of historical relics.
  36. Friis, Tyge Brahe, p. 308.
  37. I have looked through the Gazette de France for 1652, in the hope that Huet might have sent a letter from Stockholm in which he might have described his trip to Hveen. But there is nothing from him or about him, so that the only account is the one given in his book Petri Danieli Huetii, Episcopi Abrincensis, Commentarius de rebus ad eum pertinentibus, Amsterdam, 1718, 12mo, p. 86 et seq. As perhaps hardly one of the writers who have copied Huet's story from Weidler's Historia Astronomiæ have seen it, I have quoted it in Note G. The proverbial "oldest man in the parish," from whom Huet got his information, attributed the destruction of the buildings to weather and the carelessness of Tycho's successors.
  38. Peder Winstrup, Bishop of Lund (son of the Bishop of Seeland of the same name), is said to have produced many arguments to support the claims of the Swedish king, who had the best possible argument—the sword. Hofmann, Portraits historiques, vi. partie, p. 8. About the change of jurisdiction, see above, p. 88.
  39. Voyage d' Uranibourg par M. Picard, Paris, 1680; also in Reccuil d'Observations, 1693, and in Picard's Ouvrages de Mathematiques, Amsterdam, 1736. This little book is remarkable for containing the first distinct description of the phenomena of aberration and nutation.
  40. Philos. Trans., xxii. p. 692, xxiii. p. 1407. Hell's Reise nach Wardoe und seine Beobachtung des Venus-Durchganges, Wien, 1835, p. 161. Hell and Sainovics were at Hveen in May 1770 on their return journey from Wardöhus. They give a rude diagram showing the ramparts, with a hole filled with water in the middle; also the site of Stjerneborg, the cellar found in 1747 (erroneously placed), and a hut where some Swedes had observed the transit of Venus.
  41. Sjöborg, Samlingar for Nordens Fornälskare, iii., Stockholm, 1830, 4to, p. 71 et seq.
  42. "Fornlemningar af Tycho Brahes Stjerneborg och Uranienborg på Ön Hvén, uptäckte åren 1823 och 1824," Stockholm, 1824, 8vo. The inscription from the paper-mill given herein agrees with that of Danske Magazin. See above, p. 186.
  43. Urania, Aarbog for 1846. Af J. L. Heiberg, Copenhagen, 1846 (also in his Prosaiske Skrifter, vol. ix.), with fourteen plates, giving views of the island. On the 21st June 1846 a great festival in honour of the tercentenary of Tycho Brahe's birth was held at Hveen, attended by many thousand Scandinavians.
  44. Astronomische Nachrichten, vol. lxxii., No. 1718. The writer of the present work visited the island in 1874, at which time the ruins were still exactly in the state described by D'Arrest.