and conse at Prague in the beginning of 1599. He theory. He was the first who pointed out met with a cordial reception from the Em- the diminution of the obliquity of the peror, who conferred upon him favors and ecliptic. He detected several inequalities appointments more than sufficient to com- in the moon's motions, and determined pensate his losses in Denmark. A pension their law. He proved from the parallax of of 3000 crowns, an estate in perpetuity, a comets that these bodies are situated far town house, and the choice of various cas- beyond the orbit of the moon, tles and houses in the country, were the quently that the heavens are not, as was immediate and munificent gifts of Rudolph. then supposed, solid transparent spheres. He selected the castle of Benach, but after He formed the first table of refractions; a few months transferred his family and imperfect, no doubt, as it extended only to instruments to a house which had been pur- 45° in altitude;-but before the discovery chased for him in Prague. But his career of the telescope, the effect of refraction bewas now drawing to a close. He removed yond that altitude was insensible. He into Prague in February, 1601. On the 13th troduced into Practical Astronomy various of October, in the same year, while sup- improvements on the methods of observping at the table of a nobleman, where ing; and he set the example of carefully they drank freely, he experienced some verifying his instruments, and ascertaining feelings of discomfort; but, from motives the amount of instrumental errors. of courtesy, he remained at table, and on his return home was seized with a retention of urine, in consequence of which he expired, after ten days of extreme suffering. He died in the 55th year of his age; his last words, repeated frequently during his delirium, being Ne frustra videar vixisse. Such is a brief outline of the life of this remarkable man. To appreciate the services which he rendered to Astronomy, it is necessary to consider the state of the science at the time he commenced his labors. The question between the rival theories of Ptolemy and Copernicus was then undecided; and as both hypotheses sufficed for the explanation of the observed phenomena, and afforded nearly equal facilities for calculation, no further advance could be made without more numerous and accurate observations. This was precisely what Tycho undertook to supply. Born in a favorable position, possessing independent resources, and liberally aided by the King of Denmark, he erected an Observatory of more than regal magnificence; constructed or procured instruments superior in magnitude and accuracy to any that had been previously seen; engaged the services of able and zealous assistants, and devoted himself to assiduous observations during a long series of years. The result was the accumulation of a large mass of very accurate observations, which, falling into the hands of Kepler, led to the discovery of the true nature of the planetary orbits, and a complete revolution in Astronomy. Although Tycho's principal merit is that of a diligent and accurate observer, various results which he deduced from his observations were important improvements in But the most valuable result of his labors is his The claim of Tycho to be regarded as a Martyr of science rests solely on the circumstances, whatever they were, that led to the withdrawal of his pensions, and his exile from Denmark. Among the losses he sustained on this occasion, the one which he must have most regretted was his observatory, which had been erected at so great an expense, and of which his biographers have given such glowing descriptions descriptions which, were it not for the minuteness of their details, and the confirmation they receive from the plans and drawings given by Tycho himself, we might almost suppose to have belonged to a romance. The following extract will show Tycho's notions of the accommoda * The Catalogues of Ptolemy, Ulugh Beigh, Tycho Brahé, Hevelius, deduced from the best and a Preface to each Catalogue.' By Francis authorities; with various Notes and Corrections, Baily, Esq. Forming Vol. XIII. of the Memoirs of the Royal Astronomical Society. tion required for an astronomer. After describing the ceremony of laying the foundation, which was done in presence of the King, and at which copious libations of a variety of wines were offered for the success of the undertaking,' Sir David Brewster thus proceeds : of the most distinguished astronomers, from Hipparchus and Ptolemy down to Copernicus, and with inscriptions and poems in honor of astronomers.'—(Pp. 140—151.) Not the least remarkable circumstance connected with this magnificent structure, was its speedy demolition, without apparent cause or object. Even when Gassendi wrote, the edifice, with all its towers and The observatory was surrounded by a rampart, each face of which was three hundred feet long. About the middle of each face the rampart became a semicircle, the inner diame-ramparts, had entirely disappeared-jam ter of which was ninety feet. The height of the rampart was twenty-two feet, and its thick ness at the base twenty. Its four angles corresponded exactly with the four cardinal points. and at the north and south angles were erected turrets, of which one was a printing-house, and the other the residence of the servants. Gates were erected at the east and west angles, and above them were apartments for the reception of strangers. Within the rampart was a shrubbery with about three hundred varieties of trees; and at the centre of each semicircular part of the rampart was a bower or summer-house. This shrubbery surrounded the flower-garden, which was terminated within by a circular wall about forty-five feet high, which enclosed a more elevated area, in the centre of which stood the principal building of the observatory, and from which four paths led to the above-mentioned angles, with as many doors for entering the garden. "The principal building was about sixty feet square. The doors were placed on the east and west sides; and to the north and south fronts were attached two round towers, whose inner diameter was about thirty-two feet, and which formed the observatories, which had windows in their roof that could be opened towards any part of the heavens.The accommodations for the family were numerous and splendid. Under the observatory, in the south tower, was the museum and li brary; and below this, again, was the laboratory, in a subterraneous crypt, containing sixteen furnaces of various kinds. Beneath this, was a well forty feet deep, from which water was distributed by syphons to every part of the building.' seges est ubi Troja fuit-and when Picard was sent to Huen, by the Academy of Sciences of Paris, in 1671, for the purpose of determining the exact position of the spot where the instruments had stood, he found only some remains of foundations; the whole structure, he remarks, having been demolished soon after Tycho's departure, and the materials partly used in the construction of a farm-house. What renders its demolition more unaccountable, is the circumstance, that in the time of Tycho the island contained only one village, with about forty inhabitants. It could scarcely be necessary to pull down a castle to obtain building materials for the houses required by such a population. The causes of Tycho's rupture with the Danish court have been left by preceding biographers without satisfactory explanation; and Sir David Brewster has not thrown any new light on the subject. Tycho himself does not name his persecutors; but, in his elegies and private letters, hints at vague charges of ingratitude and oppression; declares he will tell all at the proper time and in the proper place: and piously suggests that his persecution was ordained by Providence, for the purpose of more widely diffusing a knowledge of astronomy. The reasons set forth in the following paragraph, afford no satisfactory explanation of the mystery : 'As the two towers could not accommodate 'For several years the studies of Tycho had the instruments which Tycho required for his been treated with an unwilling toleration by observations, he found it necessary to erect, on the Danish court. Many of the nobles envied the hill about sixty paces to the south of Uran- the munificent establishment he had received iburg, a subterranean observatory, in which from Frederick, and the liberal_pension which he might place his larger instruments, which he drew from the treasury. But among his required to be firmly fixed, and to be protect- most active enemies were some physicians, ed from the wind and weather. This obser- who envied his reputation as a successful and vatory, which he called Stiern-berg [Stierna gratuitous practitioner of the healing art. burg], or the mountain of the stars, consisted Numbers of invalids flocked to Huen; and of several crypts, separated by solid walls, diseases, which resisted all other methods of and to these there was a subterr anean pas- cure, are said to have yielded to the panaceal sage from the laboratory in Uraniburg. The prescription of the astrologer. Under the invarious buildings which Tycho erected were fluence of such motives, these individuals sucin a regular style of architecture, and were ceeded in exciting against Tycho the hostility highly ornamented, not only with external of the court. They drew the public attention decorations, but with the statues and pictures to the exhausted state of the treasury. They maintained that he had possessed too long the estate in Norway, which might be given to men who labored more usefully for the commonwealth; and they accused him of allowing the chapel at Rothschild to fall into decay.' (P. 168.) The story about the jealousy of the physicians is given by Gassendi in rather stronger terms; but it would seem to rest on no better foundation than the following verses, in an elegy composed by Tycho on the occasion of his departure. After alluding to his medical practice he adds 'Nec tamen hinc lucrum sectabar, ut undique moris ; Gratis quippe dabam parta labore gravi Nimirum hoc fuerat cur tanta odia invida sensi, Hinc abitus nostri manat origo vetus.' their report; nor is it probable that Chemistry lost much by the prohibition of Tycho's experiments. The charges against Walchendorp would seem to require some further support, in order to entitle them to be received as matter of authentic history. Beyond the credit due to Tycho as a practical Astronomer, his character presents few points for admiration, and is even stained with the grossest weaknesses and defects. He was a believer in Astrology, and a confirmed Alchemist ;-the discoverer of a new elixir, or universal remedy, 'which went by his name, and was sold in a specific every apothecary's shop as against the diseases which were then ravaging Germany.' Astrologer, alchemist, and quack, he also aspired to be regarded as a conjurer. 'He had various automata, with which he delighted to astonish the Jessenius, in the funeral oration printed at peasants; and by means of invisible bells, the end of Gassendi's Memoir, ascribes which communicated with every part of the cause of his misfortunes to his plain- his establishment, and which rung with ness of speech; 'Nihil fictum, nihil simu- the gentlest touch, he had great pleasure latum in ipso; sed scapham appellabat; in bringing any of his pupils suddenly beunde omne quod sustinuit odium.' Our au- fore strangers, muttering at a particular thor, in common with the other biographers time the words "Come hither, Peter," as of Tycho, has ascribed his persecution to if he had commanded their presence by Walchendorp, the President of the Danish some supernatural agency.' (P. 196.) Council, whose hostility is said to have had The following extract shows that the study its origin in a quarrel about a dog. Some of Astronomy had not elevated his mind symptoms of public feeling having manif st- above the most abject superstitions:ed themselves in favor of Tycho, after his retirement from Huen to Copenhagen, 'If, on leaving home, he met with an old Walchendorp-a name,' says Sir David, woman, or a hare, he returned immediately to 'which, while the heavens revolve, will be his house. But the most extraordinary of all his peculiarities remains to be noticed:- When pronounced with horror by astronomershe lived at Uraniburg, he maintained an idiot saw the change of sentiment which his of the name of Lep, who lay at his feet wheninjuries had produced, and adopted an art- ever he sat down to dinner, and whom he fed ful method of sheltering himself from pub- with his own hand. Persuaded that his mind, lic odium. He appointed a when moved, was capable of foretelling future committee of two persons, one of whom events, Tycho carefully remarked every thing was Thomas Feuchius, to report to the he said. Lest it should be supposed this was done to no purpose, Longomontanus relates government on the nature and utility of that when any person in the island was sick, the studies of Tycho. These two indi- Lep never, when interrogated, failed to previduals were entirely ignorant of astron-dict whether the patient would live or die.'— omy and the use of instruments; and even (P. 197.) if they had not, they would have been equally subservient to the views of the min- Our author, in an eloquent paragraph ister. They reported that the studies of which we regret our limits will not permit Tycho were of no value, and that they us to transfer wholly to our pages, has, mere not only useless, but noxious. Armed with a view to extenuate some of these with this report, Walchendorp prohibited defects in Tycho's character, discussed the Tycho, in the King's name, from continuing question how far a belief in Alchemy, and his chemical experiments.'-(P. 171.) Passing over the assumed subserviency of Feuchius and his coadjutor, we may remark, that Astronomers have no great reason to find fault with the sentence consequent on the practice of its arts, have a foundation The history of learning furnishes us with many examples of that species of delusion in which a great mind submits itself to vulgar adulation, and renounces unwillingly, if it renounces at all, the unenviable reputation of supernatural agency. In cases where self-interest and ambition are the basis of this peculiarity of temperament, and in an age when the conjurer and the alchemist were the companions and even the idols of princes, it is easy to trace the steps by which a gifted sage retains his ascendency among the ignorant. The hecatomb, which is sacrificed to the magician, he receives as an oblation to his science; and, conscious of possessing real endow ments, the idol devours the meats which are offered to him, without analyzing the motives and expectations under which he is fed. Even when the idolater and his god are not placed in this transverse relation, the love of power or of notoriety is sufficient to induce good men to lend a too willing ear to vulgar testimony in favor of themselves; and in our own times, it is not common to repudiate the unmerited cheers of a popular assembly, or to offer a contradiction to fictitious tales which record our talents or our courage, our charity or our piety.'-(P. 191.) this tuition Kepler made rapid advances; and on taking his degree of master in 1591, he held the second place at the annual ex amination. In the biographies of great inventors we expect to find, almost as matter of course, not only some manifestations of the ruling passion in early youth, but indulgence in the favorite pursuits at a more advanced period, in spite of every obstacle and discouragement. Thus Tycho was sent to Leipsic to study Law, but passed his nights in measuring the distance of the stars. Galileo was placed at Pisa to study Medicine, but gave his whole mind to mechanics. Kepler, however, cannot be cited as an example in illustration of the rule, for he took to astronomy as a matter of duty. On the recommendation of Mostlin, he was appointed, iu 1594, to the professorship of Astronomy at Gratz-an office for which he had, at that time, no particular qualification; and he himself states, that he had no predilection for the science, but having been educated at the public expense, he felt himself constrained to accept the first We proceed now to a character of a very appointment that was offered him. His atdifferent class;-one of those rare men, tention being thus directed to Astronomy, says Laplace, whom nature bestows from he embarked in the study with the eagertime to time on the sciences, in order to ness for which he was remarkable through develope the great theories prepared by the life, devoting the whole energies of his labors of many ages. Kepler was born at mind to discover the causes of the number, Wiel, in the duchy of Wirtemberg, on the the size, and the nature of the planetary 21st of December 1571, and was conse- orbits. The fruits of this application apquently twenty-four years younger than peared in 1596, in his Prodromus of CosTycho, and seven years younger than mographical Dissertations ;'-a work of Galileo. His father and mother are repre- which the object appears to have been to sented as having both been of noble extrac- prove, that the Creator of the universe had tion, but reduced to indigence by their observed the relations among the five reimprovidence or bad conduct. The nobility gular solids, in determining the order, of his descent, however, afforded him no number, and proportions of the planetary immunity from the usual inconveniences of orbits. Wild and extravagant as were the poverty: his father, who had been a petty theories propounded in this remarkable volofficer in the Duke of Wirtemberg's ser- ume, the boldness and originality of genius, vice, became ultimately the keeper of a as well as powers of application which it tavern at Elmendingen; and he himself, at manifested, called forth the approbation of the age of twelve years, was employed in Galileo and Tycho, and stamped the author menial. offices in this establishment. In his as one of the first Astronomers of the age. youth he was of a feeble and delicate con- Kepler's position at Gratz was by no means stitution, and subject to periodical attacks an agreeable one. The feuds between the of severe illness. At the age of fifteen he Catholics and Protestants, which then agiwas admitted into the school of the mo- tated the city, were a source of continual nastery of Maulbronn, whence, in due time, annoyance to him; his income was insuffihe proceeded to the university of Tubingen. cient for his support; he had married, and Here he had Michael Mastlin for his pre- his wife's dowery having turned out less than ceptor in mathematics-an Astronomer of he had been led to expect, he was involved no mean repute, and to whom the credit is in disputes with her relations. In 1600, he due of being one of the first who publicly visited Tycho at Prague, for the purpose taught the system of Copernicus. Under of obtaining from that Astronomer more accurate data for the determination of the at this period of his life, and indeed by far eccentricities of the planets; and an ar- the most valuable of all his productions, rangement was proposed whereby he should was his 'Commentaries on the Motions of become one of Tycho's assistants. Before Mars,' which appeared in 1609. In this this plan could be carried into effect, Kep- remarkable work he has recorded the variler, in consequence of fresh troubles at ous steps by which he was led to two of Gratz, was induced to resign his appoint- his greatest discoveries; namely, that the ment at that place; and being thus left orbit of Mars is an ellipse having the sun without the means of subsistence, he ap- in one of its foci; and that the time of deplied for the professorship of medicine scribing any arc is proportioned to the area at Tubingen. From this purpose, which included between the curve and two straight would probably have given an entirely lines drawn from the sun to the extremities different direction to his studies, he was of the arc. These important laws, todissuaded by Tycho; who invited him to gether with the correct views on gravity Prague, presented him to the Emperor, disclosed in this work, entitle its author and procured for him the title and emolu- to be regarded as the precursor of Newton ments of imperial mathematician, on the and Laplace, and the founder of celestial condition that he should assist in reducing mechanics. the observations. Longomontanus was at As an account of this volume, and Kepthat time Tycho's first assistant, and it was ler's principal astronomical discoveries, has agreed that they should undertake the com- been given in a former number of this putation, from Tycho's observations, of an Journal, we shall not dwell on them here, entirely new set of astronomical tables; to but proceed to give a few more incidents be called, in honor of the Emperor, the of his personal history. The melancholy Rudolphine Tables.' The proposal was posture of his private affairs about this encouraged by the Emperor, who pledged time, is thus described by Sir David Brewhimself to defray the expenses of the pub-ster :lication; but the death of Tycho in 1601, and the return of Longomontanus to Copenhagen, put an end to the scheme for the present. When Kepler presented to Rudolph the volume which contained these fine discoveries, he reminded him jocularly of his requiring the sinews of war to make similar attacks upon the Upon the death of Tycho, Kepler suc- other planets. The Emperor, however, had ceeded him as first mathematician to the more formidable enemies than Jupiter and Emperor, and came into possession of his Saturn, and from the treasury, which war had invaluable collection of observations. To exhausted, he found it difficult to supply the wants of science. While Kepler was thus inthis office a handsome salary was attached; volved in the miseries of poverty, misfortunes but the imperial treasury being drained by of every kind filled up the cup of his adversity. expensive wars, Kepler experienced great His wife, who had long been the victim of low difficulties in providing subsistence for his spirits, was seized, towards the end of 1610, family. But his astronomical pursuits were with fever, epilepsy, and phrenitis, and before not forgotten. 'No adverse circumstances she had completely recovered, all his three children were simultaneously attacked with were capable of extinguishing his scientific the small-pox. His favorite son fell a victim ardor, and, whenever he directed his vigor- to the malady, and at the same time Prague ous mind to the investigation of phenome- was partially occupied by the troops of Leona, he never failed to obtain interesting pold. The part of the city where Kepler reand original results.' At this period, he sided was harassed by the Bohemian levies, occupied himself with researches on the and, to crown the list of evils, the Austrian subject of refraction. His Supplement troops introduced the plague into the city.'(P. 22S.) to Vitellio' was published in 1604;—a work which contained the best account of astronomical optics then extant, and in which the offices performed by the different parts of the eye, in the act of vision, were first distinctly explained. In 1611, he published another work on the same subject, his Dioptrics,' which contains the first theoretical explanation which was given of the construction of the telescope. But the most important result of his labors OCTOBER, 1844. 16 In conseqence of his pecuniary embar rassments, Kepler made an attempt to obtain a Professorship at Linz, in Austria; but the Emperor would not consent to his leaving Prague, and encouraged him with hopes of payment of the arrears of his salary. On the death of Rudolph, Kepler again received the appointment of imperial * Vol. v. p. 442. |