"Sir!"

They surged from their chairs, on the point of blows, and stood with baleful glares locked like antlers. Into the heaving silence Barbara dropped a fat little giggle. She clapped a hand to her mouth. Regina watched her with interest. The men subsided, breathing heavily, surprised at themselves.

"He believes he is dying, you know, papa," Barbara said, with another gulp of manic laughter. "He says, he says he has the mark of a cross on his foot, at the place where the nails were driven into the Saviour, which comes and goes, and changes colour according to the time of day-isn't that so, Johannes?" She wrung her little hands, she could not stop. "Although I cannot see it, I suppose because I am not one of your elect, or I am not clever enough, as you… as you always…" She faded into silence. Johannes eyed her for a long moment. Jobst Müller waited. He turned to Barbara, but she looked away. He said to his son-in-law:

"What sickness is it that you think has afflicted you?" Johannes growled something under his breath. "Forgive me, I did not hear…?"

"Plague, I said."

The old man started. "Plague? Is there plague in the city? Barbara?"

"Of course there is not, papa. He imagines it."

"But…"

Johannes looked up with a ghastly grin. "It must start with someone, must it not?"

Jobst Müller was relieved. "Really," he said, "this talk of… and with the child listening, really!"

Johannes turned on him again.

"How would I not worry, " he said, "when I took my life in my hands by marrying this angel of death that you foisted on me?"

Barbara let out a wail and put her hands to her face. Johannes winced, and his fury drained all away, leaving him suddenly limp. He went to her. Here was real pain, after all. She would not let him touch her, and his hands fussed helplessly above her heaving shoulders, kneading an invisible projection of her grief. "I am a dog, Barbara, a rabid thing; forgive me," gnawing his knuckles. Jobst Müller watched them, this little person hovering over his big sobbing wife, and pursed his lips in distaste. Regina quietly left the room.

"O Christ," Kepler cried, and stamped his foot.

He was after the eternal laws that govern the harmony of the world. Through awful thickets, in darkest night, he stalked his fabulous prey. Only the stealthiest of hunters had been vouchsafed a shot at it, and he, grossly armed with the blunderbuss of his defective mathematics, what chance had he? crowded round by capering clowns hallooing and howling and banging their bells whose names were Paternity, and Responsibility, and Domestgoddamnedicity. Yet O, he had seen it once, briefly, that mythic bird, a speck, no more than a speck, soaring at an immense height. It was not to be forgotten, that glimpse.

The 19th of July, 1595, at 27 minutes precisely past 11 in the morning: that was the moment. He was then, if his calculations were accurate, 23 years, 6 months, 3 weeks, 1 day, 20 hours and 57 minutes, give or take a few tens of seconds, old.

Afterwards he spent much time poring over these figures, searching out hidden significances. The set of date and time, added together, gave a product 1,652. Nothing there that he could see. Combining the integers ofthat total he got 14, which was twice 7, the mystical number. Or perhaps it was simply that 1652 was to be the year of his death. He would be eighty-one. (He laughed: with his health?) He turned to the second set, his age on that momentous July day. These figures were hardly more promising. Combined, not counting the year, they made a quantity whose only significance seemed to be that it was divisible by 5, leaving him the product 22, the age at which he had left Tübingen. Well, that was not much. But if he halved 22 and subtracted 5 (that 5 again!), he got 6, and it was at six that he had been taken by his mother to the top of Gallows Hill to view the comet of 1577. And 5, what did that busy 5 signify? Why, it was the number of the intervals between the planets, the number of notes in the arpeggio of the spheres, the five-tone scale of the world's music!… if his calculations were accurate.

He had been working for six months on what was to become the Mysterium cosmographicum, his first book. His circumstances were easier then. He was still unmarried, had not yet even heard Barbara's name, and was living at the Stiftsschule in a room that was cramped and cold, but his own. Astronomy at first had been a pastime merely, an extension of the mathematical games he had liked to play as a student at Tübingen. As time went on, and his hopes for his new life in Graz turned sour, this exalted playing more and more obsessed him. It was a thing apart, a realm of order to set against the ramshackle real world in which he was imprisoned. For Graz was a kind of prison. Here in this town, which they were pleased to call a city, the Styrian capital, ruled over by narrow-minded merchants and a papist prince, Johannes Kepler's spirit was in chains, his talents manacled, his great speculative gift strapped upon the rack of schoolmastering-right! yes! laughing and snarling, mocking himself-endungeoned, by God! He was twenty-three.

It was a pretty enough town. He was impressed when first he glimpsed it, the river, the spires, the castle-crowned hill, all blurred and bright under a shower of April rain. There seemed a largeness here, a generosity, which he fancied he could see even in the breadth and balance of the buildings, so different from the beetling architecture of his native Württemberg towns. The people too appeared different. They were prome-naders much given to public discourse and dispute, and Johannes was reminded that he had come a long way from home, that he was almost in Italy. But it was all an illusion. Presently, when he had examined more closely the teeming streets, he realised that the filth and the stench, the cripples and beggars and berserks, were the same here as anywhere else. True, they were Protestant loonies, it was Protestant filth, and a Protestant heaven those spires sought, hence the wider air hereabout: but the Archduke was a rabid Catholic, and the place was crawling with Jesuits, and even then at the Stiftsschule there was talk of disestablishment and closure.

He, who had been such a brilliant student, detested teaching. In his classes he experienced a weird frustration. The lessons he had to expound were always, always just somewhere off to the side of what really interested him, so that he was forever holding himself in check, as a boatman presses a skiff against the run of the river. The effort exhausted him, left him sweating and dazed. Frequently the rudder gave way, and he was swept off helplessly on the flood of his enthusiasm, while his poor dull students stood abandoned on the receding bank, waving weakly.

The Stiftsschule was run in the manner of a military academy. Any master who did not beat blood out of his boys was considered lax. (Johannes did his best, but on the one occasion when he could not avoid administering a flogging his victim was a great grinning fellow almost as old as he, and a head taller.) The standard of learning was high, sustained by the committee of supervisors and its phalanx of inspectors. Johannes greatly feared the inspectors. They dropped in on classes unannounced, often in pairs, and listened in silence from the back, while his handful of pupils sat with arms folded, hugging themselves, and gazed at him, gleefully attentive, waiting for him to make a fool of himself. Mostly he obliged, twitching and stammering as he wrestled with the tangled threads of his discourse.

"You must try to be calm," Rector Papius told him. "You tend to rush at things, I think, forgetting perhaps that your students do not have your quickness of mind. They cannot follow you, they become confused, and then they complain to me, or…" he smiled "… or their fathers do. "