'It was a gateway,' I confided.

'To another world,' said Bernice, smiling at Lord Roxton and daring him to disbelieve us.

'Another world, eh? I dare say the huntin' there would be an experience an'

a half.'

'I take it from what you said earlier that you are one of Mycroft's agents,' I said to him. 'What brought you here?'

He rubbed a hand across his beard.

'I work for the Diogenes on and off. Nothin' formal, but I occasionally pick up the odd snippet of information here an' there. Feel it's me duty to let someone know. Mycroft knew I was comin' to India on a tiger shoot an'

asked me to have a sniff around, see what I could come up with. Cabled me last week, told me you were comin' out as well, an' asked me to keep an eye on you.'

'What made you come to Jabalhabad?' Bernice asked. 'We only came across a clue that led us here by accident.'

'I've been tryin' to track the members of Maupertuis's ragtag army,' Roxton admitted. 'They've been comin' ash.o.r.e all around the place - Calcutta, Bombay, Lah.o.r.e - an' some even slipped across from Afghanistan. I picked up a hint of some Englishmen headin' for here when I was in Sind, so I popped across to have a look-see.'

He frowned.

'Knew Tir Ram from fox-huntin' back in Blighty,' he added. 'Members of the Quantock, both of us. Surprised to find him mixed up in all this.'

'I suspected from the start that we had walked into a trap,' Holmes snapped.

'Is that why you accepted the drugged betel nut?' Bernice asked.

He gazed superciliously at her.

'I palmed the nut and feigned unconsciousness. I felt it was the best way to force their hand.'

'You were takin' a bit of a risk,' Roxton said admiringly. 'Hate to admit it, but I was taken in completely. Me head feels like a ruddy rugger ball after the International.'

Bernice leaned towards me.

'Do you believe him?' she whispered.

'Of course.'

'It occurs to me that your Mr Holmes is a bit of a showoff. Doesn't like to admit that he can be wrong.'

'He so rarely is.'

She smiled.

'How do you know?'

Leaving me with that thought, she walked off towards where Surd had fallen. For a moment it occurred to me to protect her from the sight, but I quickly realized that she would not thank me. She gave the impression of having seen a lot worse. I turned my attention back to Holmes and Roxton.

'It was Colonel Warburton's reappearance that alerted me,' Holmes was saying. 'I believe that our initial meeting with him on the Orient Express was accidental - he was, no doubt, in the process of winding down the overland transfer route for Maupertuis's troops - but our second meeting here was pre-planned. Either Maupertuis suspected that we would be following him or the mysterious hooded man back in England alerted him via some preternatural means. Either way, he sent Warburton to lull us into a false sense of security and reel us in, like a trout on the line.'

'This is all a bit above me head,' Roxton admitted. 'Where do we go from here?'

Holmes looked around.

'I would suggest a comprehensive sweep of the cavern for clues. I shall divide it up into areas, and a.s.sign each of you to an area. The process of searching is a painstaking one: I have often thought of writing a monograph on the subject. I shall give you all precise instructions on how to search, and what to search for. Until then, touch nothing and try not to move around too much.'

The thought of all of us scuttling like c.o.c.kroaches across the floor of the cavern as Holmes tutored us in his hallowed techniques struck me as funny. I chuckled to myself. Holmes glanced over darkly.

'That young lady is having an unfortunate effect upon your dignity, Watson,'

he snapped. 'Perhaps you should remember your age, and act accordingly.'

I stifled an incipient fit of giggles. Holmes could be so terribly pompous if he thought he was being made fun of.

'Young lady?' Roxton asked, confused. 'What young lady?'

'It's a long story,' I replied.

A slight p.r.i.c.kling at the back of my neck made me turn. Professor Moriarty was standing a few feet away. His deep-set eyes examined me as he might examine a simple but rather tedious problem in mathematics. Of course, most mathematical problems were simple and rather tedious to Professor Moriarty. He was, so Holmes had led me to believe, one of the foremost authorities in the world on asteroid dynamics, having derived a result for the three-body problem using the binomial theorem and gone on to generalize it to situations involving four, five and six bodies. The whole thing sounded rather distasteful to me, but Holmes a.s.sured me that it had been a bete noir of mathematicians and astronomers ever since the time of Newton. Apparently only three other people were capable of understanding the subtleties of Moriarty's work: two of them disagreed so violently over the implications that they had come to blows during an international conference and the third one had suffered a bout of brain fever following three sleepless nights checking the details.

I had once asked Holmes why, when he had international fame and presumably fortune in his grasp, Moriarty spent so much time indulging in criminal pursuits. Holmes had puffed away on his pipe for a few moments.

'For the same reason that I resort to cocaine,' he said finally. 'To alleviate boredom. And besides, I doubt that he wastes more than half an hour a week pulling the various threads of his web of villainy. No, Moriarty is a dilettante malefactor, albeit a highly dangerous and successful one.'

Now, as I met his gaze, I tried to fathom something of the depth of purpose, the iron will, the phenomenal intellect that Professor Moriarty must possess. I failed. He could have been a minor bank manager or a crusty old prelate. He was unimpressive.

His head oscillated slightly from side to side. Holmes had described the phenomenon before, and even imitated it for me, but I still found myself slightly hypnotized by the motion. I found myself grasping for a stray b.u.t.terfly of memory. I had read descriptions of symptoms such as his before, in an article by the French neurologist Gilles de la Tourette. The tics and twitches of the head, allied with the phenomenal quickness of thought and the relaxation of 'moral' guidance, were typical symptoms. Could it be that Professor Moriarty suffered from a minor form of Tourette's Syndrome?

'I do not intend to spend my time scrabbling around the floor for you, Mr Holmes,' Moriarty said quietly. 'I have done what I set out to do, and traced my missing men. They are beyond my reach now. Naught else remains. I shall return to England.'

'Really?' Holmes snapped back. 'You surprise me. Are there no dacoit or thuggee gangs with whom you can debate unusual techniques of murder?

Can you not spare a few weeks to travel to China and discuss plans for world domination with the Si Fan's Council of Seven?'

'Such sarcasm,' Moriarty whispered. 'You should take care. It may be the death of you.'

'Should I take that to be a threat?'

'I do not issue threats, Mr Holmes. Merely predictions.'

'Then I shall reply in kind. I shall see you in the dock ere long, Professor.

You have my word on it.'

Moriarty smiled: a thin, wintry flexing of the lips.

'Of what worth is the word of a drug addict?'

Holmes flinched. Moriarty turned to leave.

'Professor?'

He glanced over at me.

'Doctor Watson?'

I waved a hand to indicate the cavern and, in a wider sense, all that had occurred there.

'You seem remarkably unaffected by all of this. Does it not surprise you in any way?'

He thought for a moment.

'I have no expectations, therefore nothing that occurs in the world is a surprise. But, if it makes you feel better, the mathematics of folding higher dimensions are relatively simply. I am currently writing a paper on the subject. Perhaps I could send you a copy?'

'I cannot promise to understand it,' I rejoined.

'n.o.body will understand it, apart from myself' He did not appear to be boasting.

'You don't want to be understood?' I was intrigued. Perhaps this provided the key to his character.

He gazed at me for a few long moments, his head moving like a cat eyeing up a bird, or a cobra preparing to strike.

'I merely wish to be noticed,' he said finally, and smiled slightly. He knew what I was digging for.

'That's hardly an excuse for your crimes,' Holmes interjected.

'It is not meant to be an excuse,' Moriarty said, still gazing at me. 'It is meant to be an explanation.'

He took a step toward me and held out an object in a thin hand. It was a page torn from a notebook, covered in a thin, spidery handwriting.

'You may find this advance preview of my paper useful,' he said.

And with that he left.

'If you've finished playing dominance games,' Bernice shouted from where she crouched, near to the scattered remnants of one of the fires, 'then you might be interested in this.'

I crumpled the piece of paper up and shoved it into a pocket. Holmes and I walked over to join Bernice whilst Roxton set to work cleaning the rifle with which he had shot the raksha.s.sa. Moriarty's footsteps echoed for some little while as he climbed up the stairs towards the Nizam's palace.

Bernice was bending over the body of Surd, which. looked larger in death than it had in life. I bent and quickly checked the cadaver over. Most of his bones were shattered or twisted, and his face had impacted upon a sharp fragment of rock. Fortunately, his glossy thatch of hair had fallen forward to cover the ruin.

I couldn't say that I was sorry about his fate.

Holmes bent, took a firm grip on the back of Surd's head, and pulled. The results were startling. Surd's hair came away in his hand, revealing a naked scalp, crisscrossed with thick, worm-like scars.

'Interesting,' he commented dryly, and examined the hairpiece inside and out.

'A fine piece of work,' he murmured. 'Made by Meunier of Gren.o.ble, if I don't miss my guess. What do you think, Watson?'

I opened my mouth to answer but as usual he wasn't listening. Instead, he sniffed at the wig, then spent some moments parting the hairs and subjecting the surface in which they had been woven to a close examination, as if he were searching for lice.

'Hmmm. Most instructive.'

Placing the wig into a pocket, he turned his attention upon the corpse itself, running his fine, sensitive fingers over the fissured skin of Surd's head.

'There's something about these scars that intrigues me,' he muttered, retrieving his magnifying gla.s.s and scrutinizing Surd's scalp from close range. His forefinger traced a path amongst the cicatrices: along for a few inches, then down towards the nape of the neck, across for a few more inches and finally up, arriving at the point he had left.

'They're too regular,' he finished.

Bernice gasped.

'But that's . .

'Impossible?'

'I was going to say "ingenious": I could contain myself no longer.

'What are you suggesting?' I asked.

Instead of replying, Holmes removed a penknife from his pocket. Choosing a small blade, he placed its edge against one of the scars, as if he was going to make an incision.

'Surely surgery is my province?' I joked. Holmes did not smile.

The blade slipped too easily out of sight, as if a cut had already been made. Holmes twisted the knife, and I watched in astonishment as a section of Surd's skull, some four inches by three, lifted away in Holmes's hand.

'Voila,' my friend exclaimed. 'The perfect smuggler's hiding place.'

I gazed at the small, dark s.p.a.ce thus revealed. It had been lined with velvet, now slightly stained by the cranial fluids, and st.i.tched to the skin of the scalp. I presumed that the st.i.tching had also sealed the gap in the dura and pia mater membranes. I estimated that about half of Surd's brain must have been removed to create the s.p.a.ce.

'Fascinating,' Holmes murmured.

'Sick,' said Bernice. 'Are you seriously suggesting that the books were smuggled out of the Library inside the head of this ape?'

'The s.p.a.ce is obviously not large enough to hold more than a few pages, tightly folded. Perhaps the books were smuggled out a piece at a time.

There is some collateral evidence to suggest this.'

'What evidence?' I asked.

'Do you not remember your interview with Mrs Prendersly? Did you not repeat to me her a.s.sertion that she had seen the shadow of a man eating books? I put it to you, Watson, that what she actually saw was Surd here inserting a small volume into this s.p.a.ce.'

'And that was why she was . . . killed in such a terrible way?'

'Quite possibly, although she did repeat to you the chant that her husband had overheard and which, it transpires, is the, key to unlocking the dimensional gateway. I can imagine that Maupertuis would wish to silence anybody who knew that information. The question remains, however: how did Maupertuis determine that she knew anything?'

I tried to think, but I found that I could not look away from the gaping s.p.a.ce in Surd's head.

'I cannot accept that Maupertuis would do this to his servant.'