"Thank you, Mrs Hudson," Holmes said. "That would be most kind."

Mrs Hudson placed a calling card on the tray by the doorway. Holmes rose to his feet, but did not trouble to read the card. As our visitor entered I rose as well, and made to greet him, but Holmes spoke first.

"I observe, Dr Conan Doyle," Holmes said coolly, "that you were called abruptly into the fields, and have spent the morning investigating the mystery of the damaged crops. Investigating without success, I might add. Has a new field theorem appeared?"

Conan Doyle laughed heartily, his voice booming from his powerful chest.

"So you've introduced me already, John!" he said to me. "You were looking out the window when my carriage arrived, I've no doubt." He smiled at Holmes. "Not such a clever deduction, Mr Holmes." He wrinkled his n.o.ble brow and said to me, "But how did you know I've just come to town, and how did you know of my involvement with the field theorems?"

"I'm afraid I had no idea you were our visitor, Sir Arthur," I said. "I did not even know we had a visitor until Holmes surmised your approach."

Sir Arthur chuckled. "I understand," he said. "Bad manners, revealing the tricks of the trade. Even those as simple as prior knowledge."

Holmes concealed his annoyance; I doubt anyone who knew him less well than I would have noticed it. He gazed steadily at Sir Arthur. We seldom had visitors taller than Holmes, but Sir Arthur Conan Doyle exceeds six feet by four inches. Unlike my friend Holmes, who remained slender, indeed gaunt, even during his occasional periods of slothful depression, Sir Arthur dominated the room with his hearty presence.

"How did did you know about our visitor, Holmes?" I asked, trying to salvage the introductions. you know about our visitor, Holmes?" I asked, trying to salvage the introductions.

"I heard Sir Arthur's carriage arrive," he said dismissively, "as you would have done had you been paying attention."

Though somewhat put off by his att.i.tude, I continued. "And Sir Arthur's outing? His ident.i.ty?"

"My face is hardly unknown," Sir Arthur said. "Why, my likeness was in the Times Times only last week, accompanying a review-" only last week, accompanying a review-"

"I never read the literary section of the Times Times," Holmes said. "As Watson will attest." He pointed the stem of his pipe at Sir Arthur's pants cuffs. "You are a fastidious man, Sir Arthur. You dress well, and carefully. Your shave this morning was leisurely and complete. Your moustache is freshly trimmed. Had you planned your excursion, you would surely have worn suitable clothing. Therefore, your presence was required on short notice. You have wiped the mud of the fields from your boots, but you have left a smear on the polish. You have confronted a puzzle that has distracted you from your customary appearance, which I can easily see-anyone could easily see!-is impeccable. As to the nature of the puzzle, unripe seed-heads of Tritic.u.m aestivum Tritic.u.m aestivum have attached themselves to your trousers cuffs. I am in no doubt that you investigated the vandalism plaguing fields in Surrey." have attached themselves to your trousers cuffs. I am in no doubt that you investigated the vandalism plaguing fields in Surrey."

"Amazing," Conan Doyle whispered, his ruddy face paling. "Absolutely amazing."

I could see that Holmes was both pleased by Conan Doyle's reaction, and surprised that Sir Arthur did not laugh again and announce that his methods were simplicity itself.

Holmes finished his recitation. "That you have failed to solve the mystery is self-evident-else why come to me?"

Sir Arthur staggered. Leaping forward to support him, I helped him to a chair. I was astonished to perceive any weakness in a man of his const.i.tution. He was quite in shock. Fortunately, Mrs Hudson chose that moment to arrive with the tea. A good hot cup, fortified with brandy from the sideboard, revived Sir Arthur considerably.

"I do apologize," he said. "I've spent the morning in the presence of strangeness beyond any I've ever before witnessed. As you divined, Mr Holmes, the experience has distracted me. To perceive your supernatural talents so soon thereafter-!"

He took a deep draught of his tea. I refilled his cup, including rather more brandy. Sir Arthur sipped his tea, and let warm, pungent steam rise around his face. His colour improved.

"'Supernatural'?" Holmes mused. "Well-honed, certainly. Extraordinary, even. But not in the least supernatural."

Sir Arthur replied. "If John did not tell you who I am, and you did not recognize my face, then you could only have discovered my name by-reading my mind!"

"I read your name," Holmes said dryly, "from the head of your walking-stick, where it is quite clearly engraved."

Since the end of spring, the newspapers had been full of articles about mysterious damage to growing crops. Wheat stalks were crushed in great circles intersected by lines and angles, as if a cyclone had touched down to give mere humans a lesson in celestial geometry. Though the phenomena were often accompanied by strange lights in the sky, the weather was invariably fair. If the lights were lightning, it was lightning unaccompanied by thunder! No wind or rain occurred to cause any damage, much less damage in perfect geometrical form.

Many suggestions had been put forth as to the cause of the unexplained diagrams, from hailstorms to electromagnetic disturbances, but blame had not yet been fixed. The patterns were the mystery of the year; the press, in a misinterpretation of modern physics in general and the theory of Maxwell in particular, had taken to calling the devices "field theorems."

Holmes had clipped and filed the articles, and painstakingly redrawn the figures. He suspected that if the patterns were the consequence of a natural force, some common element could be derived from a comparison of the designs.

One morning, I had come into the sitting-room to find him surrounded by crumpled paper. The acrid bite of smoke thickened the air, and the Persian slipper in which Holmes kept his s.h.a.g lay overturned on the mantel among the last few scattered shreds of tobacco.

"I have it, Watson!" Holmes had waved a drawing, annotated in his hand. "I believe this to be the basic pattern, from which all other field theorems are derived!"

His brother, Mycroft, speedily dismantled his proof, and took him to task for failing to complete several lemmas a.s.sociated with the problem. Holmes, chagrined to have made such an elementary (to Holmes), and uncharacteristic, mistake, appeared to lose interest in the field theorems. But it was clear from his comments to Sir Arthur that they had never completely vanished from his attention.

After packing quickly, Holmes and I accompanied Sir Arthur to the station, where we boarded the train to Undershaw, his estate in Hindhead, Surrey.

"Tell me, Sir Arthur," Holmes said, as our train moved swiftly across the green and gold late-summer countryside, "how came you to be involved in this investigation?"

I wondered if Holmes were put out. The mystery had begun in early summer. Here it was nearly harvest-time before anyone called for the world's only consulting detective.

"It is my tenants who have been most troubled by the phenomena," said Sir Arthur, recovered from his earlier shock. "Fascinating as the field theorems may be, they do damage the crops. And I feel responsible for what has happened. I cannot have my tenants lose their livelihoods because of my actions."

"So you feel the vandalism is directed at you," said I. Sir Arthur had involved himself in several criminal cases, generally on the side of a suspect he felt to be innocent. His efforts differed from those of Holmes in that Holmes never ended his cases with ill-advised legal wrangles. No doubt one of Sir Arthur's less grateful supplicants was venting his rage against some imagined slight.

"Vandalism?" Sir Arthur said. "No, this is far more important, more complex, than vandalism. It's obvious that someone is trying to contact me from the other side."

"The other side?" I asked. "Of Surrey? Surely it would be easier to use the post."

Sir Arthur leaned toward me, serious and intense. "Not the other side of the country. The other side of... life and death."

Holmes barked with laughter. I sighed quietly. Intelligent and accomplished as my friend is, he occasionally overlooks proprieties. Holmes will always choose truth over politeness.

"You believe," Holmes said to Sir Arthur, "that a seance brought about these field theorems? The crushed crops are the country equivalent of ectoplasm and levitating silver trumpets?"

The scorn in Holmes's voice was plain, but Sir Arthur replied calmly. He has, of course, faced disbelief innumerable times since his conversion to spiritualism.

"Exactly so," he said, his eyes shining with hope. "Our loved ones on the other side desire to communicate with us. What better way to attract our attention than to offer us knowledge beyond our reach? Knowledge that cannot be confined within an ordinary seance cabinet? We might commune with the genius of Newton!"

"I did not realize," Holmes said, "that your family has a connection to that of Sir Isaac Newton."

"I did not intend to claim such a connection," Sir Arthur said, drawing himself stiffly upright. Holmes could make light of his spiritual beliefs, of his perceptions, but an insult to the familial dignity fell beyond the pale.

"Of course not!" I said hurriedly. "No one could imagine that you did."

I hoped that, for once, Holmes would not comment on the contradiction inherent in my statement.

Holmes gazed with hooded eyes at Sir Arthur, and held his silence.

"It's well known that ent.i.ties from diverse places and times-not only relatives-communicate from the other side," I said. "How extraordinary it would be, were Isaac Newton to return, after nearly two centuries of pure thought!"

"'Extraordinary,'" Holmes muttered, "would hardly be the word for it." He fastened his gaze upon Sir Arthur. "Dr Conan Doyle," he said, "if you believe spirits are the cause of this odd phenomenon-why did you engage me to investigate?"

"Because, Mr Holmes, if you you cannot lay the cause to any worldly agent, then the only possible explanation is a spiritual one. 'When you have eliminated the impossible, whatever remains, cannot lay the cause to any worldly agent, then the only possible explanation is a spiritual one. 'When you have eliminated the impossible, whatever remains, however improbable, however improbable, must be the truth'! You will help me prove my case." must be the truth'! You will help me prove my case."

"I see," Holmes said. "You have engaged me to eliminate causes more impossible than the visitations of spirits. You have engaged me... to fail."

"I would not have put it so," Sir Arthur said.

The trip continued in rather strained silence. Sir Arthur fell into a restless doze. Holmes stared at the pa.s.sing landscape, his long limbs taut with unspent energy. After an eternity, we reached the Hindhead station. I roused Sir Arthur, who awoke with a great gasp of breath.

"Ma'am!" he cried, then came to himself and apologized most sincerely. "I was dreaming," he said. "My dear, late mother came to me. She encourages us to proceed!"

Holmes made no reply.

Sir Arthur's carriage, drawn by a pair of fine bays, awaited us.

"The automobile can't be started, sir," the driver said. "We've sent to London for the mechanic."

"Very well, James," Sir Arthur said. He shook his head as we climbed into the carriage. "The motor was quite astonishingly reliable when first I bought it. But recently it has broken down more often than it has run."

The comment drew Holmes's attention. "When, exactly, did it begin to fail?"

"Eight weeks past," Sir Arthur said.

"At the same time the field theorems began to appear," Holmes said thoughtfully.

Sir Arthur chuckled. "Why, Mr Holmes, surely you don't believe the spirits would try to communicate by breaking my autocar!"

"No, Sir Arthur, you are quite correct. I do not believe the spirits would try to communicate by breaking your autocar."

"Merely a coincidence."

"I do not believe in coincidences."

Holmes was anxious to inspect the field theorems as soon as we arrived at Undershaw, but by then it was full dark. Sir Arthur showed the strain of a long and taxing day. He promised that we should leap out of bed before dawn and be at his tenant's field as the first rays of the morning sun touched the dewdrops of night.

And so we did; and so we were.

The descriptions and newspaper engravings of the field theorems did not do justice to the magnitude of the patterns. We stood on a hillside above the field to gain an overview of the damage. Three wide paths, perfectly circular and perfectly concentric, cut through the waving stalks of grain. A tangent, two radii, and a chord decorated the circles. I had to admit that the pattern resembled nothing so much as the proof of some otherworldly geometric proposition.

"The theorems appear only in wheat fields," Sir Arthur said. "Only in our most important crop. Never in fields of oats, nor in Indian corn."

Holmes made an inarticulate sound of acknowledgment.

We descended the hill, and Holmes entered the field.

Sir Arthur looked after him. "John," he said to me, "will your friend admit it, if he can find no natural explanation?"

"His allegiance is to the truth, Sir Arthur," I said. "He does not enjoy failure-but he would fail before he would propose a solution for which there were no proof."

"Then I have nothing to worry about." He smiled a bluff English smile.

Holmes strode into the swath of flattened green wheat, quartering the scene, inspecting both upright and crushed stalks, searching the hedgerows. He muttered to himself, laughed and snarled; the sound crossed the field like a voice pa.s.sing over the sea. He measured the path, the width of the stalks left standing, and the angles between the lines and curves.

The sun crept into the clear sky; the day promised heat.

"Can you feel it?" Sir Arthur said softly. "The residual power of the forces that worked here?" He stretched out his hands, as if to touch an invisible wall before him.

And indeed, I felt something, though whether it was energy spilled by unimaginable beings, or the Earth's quiet potential on a summer's day, I could not tell.

While Sir Arthur and I waited for Holmes to finish his search, a rough-shod man of middle years approached.

"Good morning, Robert," Conan Doyle said.

"Morning, Sir Arthur," Robert replied.

"Watson, this is one of my tenants, Robert Holder."

Robert's work clothes were shabby and sweat-stained. I thought he might have taken more care with his appearance, when he came to speak to his landlord.

To Robert Sir Arthur said, "Mr Holmes and Dr Watson have come to help us with our mystery."

"Mr Holmes?" Robert exclaimed.

He glanced out into the field, where Holmes continued to pace and stoop and murmur.

"And you're Dr Watson?" Robert's voice rose with the shock of finding himself in the presence of celebrity. "Why, it's a pleasure to meet you, sir," he said to me. "My whole family, we read your recountings in the evenings. The children learned their letters, sitting in my lap to listen to your tales."

"Er... thank you," I said, somewhat nonplussed. Though he was well-spoken for a farmer, I would not have marked him as a great reader; and, more, I consider the perils encountered by Holmes to be far too vivid for impressionable young children. However, it was not my place to correct Robert's treatment of his offspring, particularly in front of his landlord.

"Have you found the villains?" Robert asked. "The villains who have crushed my best wheat field!"

Holmes strode across the field and rejoined us, a frown furrowing his brow. He appeared not even to notice the presence of Sir Arthur's tenant.

"Useless," Holmes said. "Perfectly useless! Here, the artist stood to sketch the scene." He flung his hand toward a spot where white dust covered the scuffed ground. "And there! A photographer, with his camera and flash powder. Fully six reporters and as many policemen trampled whatever evidence might have been left." He did not pause to explain how he could tell the difference between the footprints of reporters and those of policemen. "And, no doubt, when the sightseers arrive by the next train-"

"I can easily warn them off," Sir Arthur said.

"To what purpose? The evidence is destroyed. No! I could conjecture, but conjecture is only half the task. Proof, now; that's a different story."

He glared out into the field as if it had deliberately invited careless visitors to blur the story written there.

"If only," Holmes said softly, "the scene were fresh."

He turned abruptly toward Robert. He had taken the measure of the man without appearing to observe him.

"You saw the lights," Holmes said. "Describe them to me."

"Are you Mr Holmes?"