Prague Pictures: Portraits of a City (22 page)

In the final years of the sixteenth century life had become extremely difficult for Protestants in the province of Styria. The Counter-Reformation was well under way, and the Catholic authorities in Graz were imposing increasingly harsh religious strictures. When in the summer of 1599 the Keplers' baby daughter Susanna died after less than a month of life, Kepler refused a Catholic burial for the infant and was consequently fined. In the autumn, rumours began to fly that soon any Lutheran moving out of the city would have his wealth and possessions confiscated, which, if the rumours were true, would mean that the Keplers would lose Barbara's considerable inheritance. There were sectarian riots in the countryside, and then in the streets of the city itself. The time had come to move on. Kepler turned his increasingly desperate attention in the direction of Prague. Tycho Brahe, the Great Dane in the manger, possessed a wealth of astronomical data. 'Only, like most rich men,' Kepler wrote to his old teacher Mastlin, 'he does not know how to make proper use of his riches. Therefore, one must take pains to wring his treasures from him, to get from him, by begging, the decision to publish all his observations without reservation.' Later, in 1601, Kepler wrote from Prague to the Italian astronomer Antonio Magini of his reasons for coming there: 'What influenced me most was the hope of completing my study of the harmony of the world - something that I have long contemplated and that I would be able to complete only if Tycho were to rebuild astronomy or if I could use his observations.' Despite his double vision, Kepler was never less than clear-eyed.

At the beginning of 1600 Kepler's chance came. An acquaintance of his, Baron Johann Friedrich Hoffmann, a wealthy, cultured man and a close adviser to the Emperor Rudolf, had been in Graz to attend a convention of the Styrian Diet and was now returning to Prague, and offered him a lift in his entourage. The Baron was of a kindly disposition, and, although a Catholic, had sympathy with Kepler's difficulties as a Lutheran. Also, Hoffmann was an amateur astronomer, and had read and admired Kepler's work. He was acquainted too with Tycho Brahe and had determined that the two men should meet. And Kepler did need a friendly advocate, for he had already blundered into a series of embarrassing and potentially disastrous misunderstandings with the prickly Dane, including seeming to back up the claims of a certain Ni-cholaus Reymers Bar - his punningly Latinised name was Ursus,
ursus
being Latin for bear who had briefly assisted Tycho on Hven, and had published a system of the world which Tycho vehemently claimed was a plagiarism of his own work; Tycho would have got in first, were it not for his extreme unwillingness to publish, since in his circle and among his family the writing of books was considered no fit occupation for a gentleman and a knight. However, Tycho in his lordly way had forgiven young Kepler his trespasses, and had written graciously to invite him to Prague, assuring him that 'whatever comes to pass, you will find in me not a follower of fortune . . . but your friend who even under untoward circumstances will not fail you with his advice and help, but rather will advance you to everything that is best,' Kepler, however, did not receive this letter, for it crossed with his journey to Prague.

Arriving in the city in the bitterly cold dawn of a new century - it was January, 1600 - Kepler, no doubt exhausted after the ten-day journey, was alarmed to find that Brahe, like Old Possum's cat Macavity, was not there. He was not even at Benatky, for he was still sheltering from the plague at Girsitz. Kepler, who had left Barbara and her seven-year-old daughter Regina in Graz, lodged with the hospitable Baron Hoffmann at his house on the
in a street behind the royal gardens that would one day be called Tychonova, named after you know who. What an adventure Prague must have been for this poor son of Weilderstadt. The transfer of the imperial court from Vienna had made Prague the first city of the empire, and for the thirty years of Rudolf's rule there it was the centre of Europe not only geographically but in terms of wealth and power. Like every capital city it acted as a magnet, drawing to it people from all over the continent, ambassadors and foreign diplomats, scholars, artists, scores of alchemists and sorcerers and, inevitably, as we have seen, countless mountebanks and swindlers. To Kepler the city must have been a dazzling spectacle, a very image of the 'gold rooms and spontaneous applause, the attention of magnificent people'
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that he had anticipated. There were magnificent Gothic palaces and Romanesque churches,
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while the Castle itself, brooding on its hill, must have seemed a city within a city. Kepler will have cast a speculative eye toward the Hradcany, Rudolf's keep, for he knew of the Emperor's enthusiasm for new science and old magic, in the first of which Kepler was an adept, and the second of which he was prepared to practise, if horoscopes and numerology should prove the route into imperial favour.

At the end of January, when the cold had killed off the last of the pestilence, Tycho returned to Benatky, and wrote another letter to Kepler. This one got delivered. In it, Tycho was promisingly cordial, inviting Kepler to the Bohemian Venice, the new Uraniborg. 'You will come,' the Dane wrote, 'not so much as guest but as a very welcome friend and highly desirable participant and companion in our observations of the heavens.' In a further show of favour he sent his son, Tycho the younger, accompanied by Franz Tengnagel, an elegant young Westphalian noble and one of the astronomer's assistants, to Prague to fetch the newcomer. When Kepler and his two escorts reached Benatky, Tycho received him warmly, offering to reimburse his travel expenses and enquiring after his family and what plans he had for his wife and stepdaughter to join him. Kepler could scarcely contain his excitement and joy. The world's greatest, or at least its most renowned, astronomer - Kepler had no doubt who the really great one was - the legendary lord of Hven, magus of Uraniborg, and now Imperial Mathematician to His Majesty Rudolf II, was shaking his hand and inviting him to join with him in work to solve the
mysterium cosmogra-phicum.

Within a day or two, however, Kepler's hopes had turned to ashes. He had not yet learned the ways of the aristocracy, and had mistaken Tycho's automatically courtly greeting for a pledge of comradeship. When the niceties were done with, Tycho promptly turned and swept away to his own concerns, which were many and burdensome. Benatky was still a building site, with workmen traipsing everywhere, hammering and whistling. Four of Brahe's most precious instruments were still on Hven, while others were in transit somewhere in the German lands. And Kepler was not the only one being disappointed in the matter of patronage: the Emperor's pledges of financial support for Tycho and his plans had not been made good, while Mlihlstein, the increasingly alarmed administrator of Benatky, was refusing to countenance further expenditure on renovations to the castle without direct authorisation from the Emperor.

Life for the exiles at Benatky was chaotic, noisy, crowded and yet isolated, 'a reigning loneliness of people,' in Kepler's mournfully poetic description - the Brahes, after all, were farther away from home than he was. Mealtimes on the upper floor of the castle were a torment for Kepler, a ceaseless din of raucous Danish talk and the clatter of crockery and wine mugs. Lord Brahe presided gloomily at the head of the table, his dwarf jester Jeppe squatting cross-legged at his feet, while his wife and their daughters squabbled and shrieked, and the numerous attendants and scientific assistants gossiped endlessly while jostling for placement above the salt. Hogsheads of wine were swilled down, so that the normally abstemious Kepler must have spent the first weeks of his stay in a more or less permanent semi-stupor. The access to astronomical treasures that Tycho had promised him was not forthcoming. Tycho himself was not forthcoming. In the course of dinner Kepler would wheedle his way up the table to where the great man sat, ignoring him except on the rare occasions when he deigned to let fall, like a scrap from his plate, a bit of information on the orbit of Mars, or lunar occlusions, or coming conjunctions between this or that of the planets. Where was that 'companionship in our observations' that Tycho had so enticingly offered? Instead of the equal in scientific knowledge that Tycho had seemed to consider him, he was, he realised, no more to the Dane than a
domesticus,
a hired man. What he did not realise was the extent of Tycho's wariness and sense of foreboding. Although Kepler was not yet the scientist that he would be in later years, he was, Tycho knew, a formidable rival in the race for immortality. One of the strong reasons for Tycho's unwillingness to give up his precious astronomical data to this young man half his age was the fear that Kepler the Copernican would use them to prove that Copernicus's sun-centred system was correct. For Tycho had his own system, a not inelegant one but, as Kepler would indeed prove, no more than a hopelessly mistaken compromise between Ptolemy's ancient geocentric model and the heliocentric version proposed by Copernicus.

In the weeks and months that followed, the little dog which Kepler had once compared himself to turned snappish, and on occasion even vicious.
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Grudgingly, Tycho had opened the coffers of his accumulated observations and given him the orbit of Mars to work on. Careful as always, however, he placed Kepler under the supervision of another Tychonic assistant, Christian Sorensen, called Longomontanus after the Danish village of Longberg where he was born how they did love those Latinate puns! - a mild, well-meaning man whose authority over him Kepler deeply though silently resented. Yet the two men worked well together, thanks mainly to Longomontanus's tolerance and unmistakable brilliance as an astronomer. In time, Tycho relaxed enough to reassign Longomontanus to lunar theory - the moon was an important player in the drama of the Tychonic system - and allow Kepler to continue to work on Mars alone, but not before he had compelled Kepler to sign a pledge not to reveal any of the secrets of the new Uraniborg to the outside world. The assignment of the Mars project to Kepler was one of history's luckier chances, since the eccentricities of that planet's orbit could only be accounted for in relation to the position of the sun, a fact which supported Kepler's long-held theory that the sun is the source of planetary motion. Those weeks of work on Mars marked the maturing of Kepler's genius as a theoretical scientist.

Growing into his greatness, Kepler began to clamour for his rights. He demanded a contract from Tycho, one that would recognise him as an equal partner in the great cosmological project under way at Benatky, and guarantee him fitting recompense for his labours. Throughout that spring, negotiations between the two men dragged on. Kepler demanded that he be paid two separate salaries, one from Tycho and one from the Emperor, that he should have all afternoons free to work on his own theories, and that he and his family - Barbara and her daughter were still in Graz, anxiously awaiting the summons to Benatky should be given a house to themselves, away from the castle and the disorderly life there. Not the least remarkable aspect of these discussions was the fact that while Kepler's hysteria and paranoia grew, Tycho displayed wholly uncharacteristic patience and forbearance. He was still suspicious of Kepler's Copernican leanings, but recognised, however unwillingly and with whatever foreboding, the young man's genius. It is possible too that beneath the aristocratic hauteur, Tycho simply liked his excitable, energetic and unintentionally comic collaborator. Certainly he indulged Kepler in ways that the other workers at Benatky would not have dared to dream of.

At the beginning of April, Tycho and Kepler sat down to thrash out an agreement, with the Emperor's chief physician, Jan Jesensky, acting as referee. Kepler had written to Tycho setting out his demands, and now Tycho produced a document in response, the main element of which was the secrecy pledge. If Kepler signed, Tycho would press the Emperor to grant Kepler a decent salary, would try to find a house for him and his family, and would pay travelling expenses for Barbara and her daughter to come from Graz. Kepler's demand for Sundays and holidays free Tycho regarded as an impertinence, insisting that he had never asked his assistants to work on those days. There was that word again: assistant. Kepler was adamant: either his demands must be met in full, or there would be no agreement. Despite Dr Jesensky's best emollient efforts the meeting broke up in rancour. At dinner that evening, in the presence of the Brahe household, Kepler got drunk on wine and launched a shrill attack on Tycho, who responded with equal energy. One imagines the scene, little Kepler, red with rage and too much alcohol, waving his fists and shrieking, while the Dane grips the edge of the table as if preparatory to upending it, the rumblings of his anger sounding like a ground bass under Kepler's frantic pipings. The following day, Kepler walked out, and returned to Prague in the company of Jesensky. Once again, Tycho displayed extraordinary restraint, although he did inform Jesensky before the two left that a written apology from Kepler would be required before he could return to Benatky and resume his work. It might be thought that this demand would send Kepler into greater heights of indignation and rage, but once back in Prague, staying probably at Baron Hoffmann's house, and no doubt urged to caution by Jesensky and the good Baron, he bethought himself and the perils of his position, and wrote a letter of apology to Tycho notable for its florid abjectness. The little dog had come to heel. Relieved, Tycho took the unprecedented step of summoning his carriage at once and riding into Prague in person to fetch the prodigal home to Benatky. Spring sunshine outside the Hoffmann house, and a humbled Kepler steps forth, blinking; alighting from his carriage the Dane sweeps forward, his metal nose agleam; a brocaded arm is thrown around drooping shoulders, gruff words are exchanged; the Baron and Dr Jesensky beam at each other over Kepler's head; the bells of St Vitus's begin to bang out a general rejoicing.