Kepler's Witch (28 page)

But what about the telescope itself? How did it work? How could it make things that were small to the naked eye appear large? How could it make things that were invisible to the naked eye become visible? Up until that time, the instrument was a mystery. Galileo had promised a report on how it worked, but he had not produced it. He was, understandably, too busy using it to make his observations. However, no one could really trust this new instrument, nor could they trust any of the discoveries that were made with it without some understanding of how it worked.

In September 1610, soon after he had finished his own observations of the planet Jupiter, Kepler wrote a short work he called the
Dioptrice,
which was the first theoretical analysis of the workings of the telescope. In this book, he set down the basic laws of optics, explaining how the passage of light through a series of lenses produces the effects it does. After his long depression, Kepler had come alive again, and as he so often did after a melancholic period, he suddenly possessed a furious kind of energy. His desire to know overwhelmed him; his desire to figure things out drove him on. In the
Dioptrice,
he described the double convex converging lens, and explained how using two or three lenses extends the effectiveness of the instrument. He also demonstrated how a set of two convex lenses can make an object appear larger while inverting the image. This led him to an explanation of Galileo's telescope, which used a converging lens in the body of the instrument and a diverging lens in the eyepiece and provided a higher magnification of objects, a serious improvement over a
telescope that employed only a single converging lens. By way of appreciation, he offered his new short work to the elector Ernst of Cologne, the man who had made available to him his own copy of Galileo's telescope.

Meanwhile, Galileo continued with his observations. His telescope was not strong enough to resolve the rings of Saturn, but he was able to see them as two fuzzy blobs sticking out on either side of the planet. He thought that Saturn was actually built that way, one large blob with two smaller blobs stuck to it like Mickey Mouse ears. Then he turned his telescope to Venus and noticed that it passed through phases like the moon. This was a proof of Copernicus, since if Venus passed through phases, then those phases likely were the result of its position relative to the sun, just as the moon's phases are the result of its position relative to the sun and the earth. It was highly likely, Galileo concluded, that the light of Venus came from the sun and was reflected off the planet's surface.

Kepler received word of these new discoveries not from Galileo, but once again from the Tuscan ambassador, Julian de' Medici, who kindly passed the reports on. He heard about Galileo's Saturn observations in the early part of August and about his Venus observations on December 11. Perhaps it was because Galileo was afraid of his enemies or perhaps because it was fun to play word games, but he cast the meat of his reports into complex puzzles. Of course, unless Galileo had already sent a key along to his correspondents in an earlier letter, none of them would have been able to read his reports. His discovery about Saturn he wrote in the single Joycean word: “Smaismrmilmepoetaleumibunenugttaurias.”
³
And later, when he reported on his discoveries about Venus, he took pity on his readers and cast his secret into a Latin anagram: “
Haec immature a me jam frustra leguntur oy,
” which is translated, “I already tried this in vain too early,” which, like all codes, means almost nothing, or almost everything.

Kepler loved ciphers and puzzles, and Galileo's way of reporting his discoveries revved him up. A secret message demands revealing, and any mathematician worth his salt would feel called upon by reason itself to tackle the problem. Kepler played with the first one, fussed with it, and tried different combinations with the same fearful determination and
intense love of his work that he had brought to bear on the problem of Mars's orbit. He sorted the letters into words and the words into phrases, thus building a message for himself out of Galileo's first meaningless code. His solution was: “
Salve umbistineum geminatum Martia proles,
” which, oddly enough, means “Greetings, twin protuberances, Mars's children.”
⁴
Kepler was wrong about the puzzle, but not about Mars. Galileo wasn't talking about Mars at all, and yet, two hundred years later, Asaph Hall, an American astronomer working at the Naval Observatory, discovered that Mars did indeed have two moons and named them Phobos and Deimos.
⁵

Galileo, however, would not reveal the secret of his puzzle, that is, until the emperor took notice and sent word to Italy that he wanted to know the secret himself. Galileo would not respond to the emperor's mathematician, but he would respond to the emperor. His own solution to the first puzzle was a Latin phrase:
“Altissimum planetam tergeminum observavi,”
which means, “I have seen the highest planet three-formed.” This meant that instead of Mars having protuberances, Saturn had them. Kepler couldn't stand it anymore, so after he received the second puzzle, he wrote a letter to Galileo, begging him to reveal the second puzzle's meaning as well. “Think of the anguish you put on me by keeping silent,” he said. On January 1, 1611, Galileo relented and sent back the answer “
Cynthiae figures aemulatur mater amoram,”
which means, “The mother of love emulates the shapes of the moon.”
⁶

Galileo never responded to Kepler about his little book, the
Dioptrice,
though it solved his problem of the telescope for him. Perhaps it is too much to ask of Galileo to expect more than that, but if it had been the other way around, Kepler would have written at once. Over the next year, Kepler wrote at least six letters to Galileo. Galileo wrote none, except a terse note recommending a young friend of his to the imperial mathematician. After that, their communication ended forever.

Then 1611 came, red with blood. Just at the end of 1610, Barbara, whose health had never been good, suddenly took sick. Illnesses came in rapid succession. First, she came down with Hungarian spotted fever, a new disease that had invaded the city along with one of the raiding armies. Then she began having epileptic seizures, which, given the med
ical prejudices of the time, must have been terrifying to everyone in the household. Imagine Kepler pacing the floor, calling for physicians, instructing her maid to watch her constantly to make sure she didn't have a seizure in her sleep. With time, however, the fever, perhaps a form of typhus, retreated, and Barbara crept toward recovery. But then came sorrow after sorrow.

Within a few weeks, all three children were in bed with high fevers, exhaustion, and body aches. Small red spots erupted on their tongues, inside their mouths, and down their throats. The spots turned to sores, which broke open and oozed liquid. A rash appeared on their faces and invaded their arms and legs; by the next day their little bodies were covered. After three days, two of the children, Susanna and Ludwig, began to feel better. The rash changed to bumps, which filled with a thick, viscous fluid, and then formed little calderas on their skin, raised rings with depressions in the middle, like thousands of belly buttons. The pustules scabbed over, and as the scabs broke open and fell away, the children rallied, chattered, ate again, whined to leave their beds to play. Kepler knew what this was, for he had suffered it himself as a child, the disease that had mangled his hands and ruined his eyes. It was smallpox, and as he watched over little Susanna and little Ludwig, praying for their recovery, he also prayed for little Friedrich, whose fever had not abated and who grew weaker every day, and he knew that Friedrich, only six years old, would not survive.

Friedrich died on February 19, in a winter full of war. “Whether you looked at the blossom of his body or the sweetness of his behavior or listened to the promising prophecies of friends, in every sense one could call him a morning hyacinth in the first days of spring, who with tender fragrance filled the house with the smell of ambrosia,”
⁷
Kepler wrote the next year. The boy was his heart, as he was his mother's. As little Friedrich lay dying, outside in the streets, soldiers marched into the city, mercenaries from Passau, sent by Archduke Leopold, that rash boy. Houses were burned and looted, families turned out onto the streets. The soldiers had not been paid, and unpaid soldiers all too quickly become beasts. Young girls screamed, raped by soldiers in back streets and alleyways. From time to time, a child was run down by horses.

In the midst of this, little Friedrich died in his bed. Cast down with grief, Barbara's recovery faltered. “The boy was so close to his mother, people would not simply see their relationship as merely love, but as a deeper, more lavish bond.” Kepler stood by, watching his wife sink into despair. After three years of illness, her mind broke down and she sat in her bed, confused and unaware. Meanwhile, outside the door, on the streets of Prague, the soldiers of Archduke Leopold, bishop of Passau, had been unleashed on the citizens. In her broken state, Barbara quivered with each gunshot and wept with each rolling boom of the cannonade. Her world had finally collapsed along with her wits. Prague had fallen to barbarians; her little boy had died in her arms—what was there left to live for? This world was altogether vile.

Running for physicians, calling upon neighbors, asking for help for his wife, Kepler must have seen much of the battle. Did he watch the Passauer cavalry slash their way across the Stone Bridge and up the street to the Old Town Square? Did he hear the horses screaming in pain, shot through the neck or through the lungs with musket fire? Did he hear the mercenaries shouting to one another, see their rage, their cruelty, and wonder if the grief inside himself over Friedrich's death would ever match the grief of the city over its dying people? Day after day of slaughter. Bohemian troops, Protestants this time, entered the city from the other side, attacking monasteries and burning churches. Protestant citizens in the Old Town Square pulled the slashing Passauer cavalry off their horses and killed them to a man. The representatives of the Estates called to Matthias for help, and he responded with another army, an Austrian army to throw the Passauers out of the city. As they arrived, however, Rudolf paid off the Passauer cavalry and the men quietly slipped out of Prague and returned home. When he arrived, Matthias was the last man standing, the only one with an intact army. He could dictate terms. Matthias forced Rudolf to abdicate in 1611, and the next year in Frankfurt, the princes elected him emperor.

Throughout these events, both sides asked Kepler for astrological advice, but knowing the damage that astrology could do to a king if used deceitfully, he gave Rudolf what advice he could without guile. Rudolf was
desperate and would have believed anything. However, whenever Rudolf's enemies asked for his advice, he was glad to tell them that the stars had lined up firmly behind the emperor. He would not say that to Rudolf, though, for the emperor's own good.

With Rudolf deposed, Kepler's need to find a new position became acute. He had been in communication with his friends and patrons in Linz for some time, mainly because he wanted to find a city about the size of Graz where Barbara could finally be happy. But in the back of his mind, there was always the hope of returning home. He wrote the Duke of Württemberg to help him obtain 2,000 talers the emperor had promised him from the House of Silesia, and in the letter he begged the duke to help him find a professorship in philosophy or to give him some other task in the duchy. What he wanted most of all was peace, peace to finish his work. His life had been anything but restful, and up until that point Württemberg had been an island of Lutheran safety in an increasingly uncertain Germany. The duke sent Kepler's request to his chancellor, who could not find anything wrong with it. Here was a good Swabian fellow who had graduated from Tübingen
summa cum laude
out of the duke's own stipend system, who had become the emperor's own mathematician, and who had become by almost everyone's accounting a great man. What better addition could he find for the duke's university? Mästlin was old and would need to be replaced soon enough. Kepler was young; he had years left in him.

Then the chancellor sent the application off to the consistory, where tongues began to wag. They searched through the files and found another letter, written only two years ago, in which Kepler said that he couldn't see why anyone who ascribed to the Calvinist doctrine of Communion could not be called a brother in Christ by his fellow Lutherans. He could not see it, but they could. This was false doctrine. This was heresy. This was criminal. This Kepler fellow was a furtive Calvinist, a heretic in Lutheran clothing. He was opinionated, with original and eccentric ideas about philosophy and, worse, about doctrine. He would poison the minds of the students, filling them with dangerous ideas. There would be controversy. Besides, all the teachers at Tübingen University had to follow the
Augsburg Confession, which meant that he had to sign the Formula of Concord. No waffling. No sly reservations. If a man could not bend to the church, then there was no place for him n Württemberg.

Personally, the duke wanted Kepler, as did the chancellor. Neither of these men was a theologian, but they were statesmen who kept their eyes open to whatever advantage they could find to help the duchy through difficult times. But to override his consistory meant that he was giving a no-confidence vote to the leaders of his own church, and that would cost him far more than having Kepler at Tübingen would gain him for the school. The duke, following the lead of the consistory, denied Kepler's application.

A slight possibility arose about a job opening up in Padua, filling Galileo's spot when he traveled to Rome. Galileo had actually recommended Kepler before the Venetian council, but nothing happened, and Kepler didn't have his heart set on the job anyway, preferring to stay in Germany. Linz looked better and better, even though Barbara was sick and failing. He traveled to Austria to arrange things, hoping that this might bring Barbara around, but when he returned to Prague, she had fallen sick once more. A new wave of illnesses had fallen on the city with Matthias's army, and Barbara, whose immune system was likely compromised by grief, had succumbed to it as well. “Just when she started to recover, however, the repeated illnesses of her children brought her down again. Her soul was deeply wounded by the death of the little boy who had been half her heart.” On top of that, the wars drove her closer toward death. “Numbed by the terrorism of the soldiers and by the bloody war in the city of Prague, despairing of a better future and consumed with grief for her dearest children, she finally contracted the Hungarian spotted fever.”