'I do not see any soldiers,' I pointed out.

'They have taken the royal family and fled to the citadel.'

'Where is the treasure house?'

'It is under the hareem,' Wazim said. 'Below the ground, you know?' As Wazim spoke these words, I recalled my midnight meeting with the Caliph and his unexpected entrance by way of the hidden tunnel.

With admirable efficiency, the treasure house had been constructed beneath the hareem so the same soldiers might guard all the caliph's various treasures at the same time. There were no lights showing in any of the windows, and the huge building was silent. 'This way,' I said, starting towards the entrance.

Although the guards were gone, the door was barred, and the bars were secured with large, iron box-like locks which required the use of keys to open. 'You see,' whispered Wazim, creeping up behind me. 'They are locked. You cannot get in. We will leave now.'

'There must be another way in.'

'There is only this way,' Wazim maintained. 'It is the hareem. There is no other way.'

'Because it is the hareem,' I contended, 'there mwsfbe another way.' Although I knew little of such things, it seemed to me unlikely that the caliph would wish his visits to his various wives to be known by one and all throughout the palace. I reckoned that, as with the private audience chamber behind the throne room, there must be another, less conspicuous entrance to accommodate his visits.

I looked around the square at the surrounding buildings. There were two long ranks of storerooms, one to the left and one behind the hareem; a wing of the palace enclosed the third side, and on the fourth side, a low building with four funnel-topped domes along the roof. 'What is that?' I asked.

'The kitchen and ovens for the hareem.'

I started towards the building. 'You will find nothing there,' Wazim said, scuttling after me.

At first look, it appeared he was right. The long, low room was empty, the large, square hearth bare, the ovens cold. There were a few loaves of bread lying on a table, and some pears in a basket, but I could see nothing else in the dark interior. I went in, and felt along the raised rim of the hearth. 'What are you doing?' said Wazim. 'They will find us. Let us go from here, my friend.'

In a moment, I found what I was looking for: a pile of straw used for kindling to start the fires. I took up a handful and bunched it in my fist, then leaned over and reached out into the centre of the hearth and swept away the top layer of ash to reveal a few glowing coals beneath. Holding the bunch next to the coals, I blew gently on the straw and was soon rewarded with a pale yellow sprout of flame. Soon the rest of the bunch was alight and, holding it up, I quickly searched the room for a candle, finding three; I lit one, stuck one in my belt, and gave the third to Wazim, and told him to stand by the door and keep watch. 'Warn me if anyone comes into the garden,' I said.

By candlelight, I made a thorough search of the kitchen, pausing only to tear one of the loaves in half and cram bits of it into my mouth. It was stale, but edible, and I resumed my search as I chewed. I searched around and between the ovens, and found a small doorway leading outside through which fuel for the hearth and ovens could be brought in. I went outside and found myself in a closed-in area stacked with wood, bundles of twigs, and straw. Cupping my hand around the flame, I moved along behind the row of ovens, and came upon a wooden cover on the ground between two of them. Lifting the cover, I held my candle into the void and saw a short flight of steps leading down.

I removed the cover quietly and set it aside, then fetched Wazim. He took one look at what I had found and said, 'It is the ash traps – for cleaning the ovens. There is nothing here.'

Ignoring him, I moved down the steps and found that he was right. A brick rampart ran along the back of a dressed stone wall, forming a large box to catch the ash falling through the oven grates above. A walkway in front of the rampart allowed the cleaners to remove the ash; at one end of the walkway was a small opening for air to feed the fires from beneath, and at the other end of the walkway, a door.

I called Wazim to follow me, and proceeded to the door. Lifting the latch, I opened the door and stepped through into the cool, damp darkness of a great, cavernous room. I heard the liquid drip of water splash in the distance. 'It is the cistern for the hareem,' Wazim announced upon joining me. His voice echoed from unseen walls. 'Come, there is nothing here.'

'But there is,' I told him. 'Look.' Raising my candle, I held it close to the wall to reveal a torch in an iron sconce beside the door. I took it up, lit it from the candle, and the resulting flame revealed a short walkway forming a ledge alongside the basin of the cistern. At the end of this walkway there was another door. 'This way.'

The door opened onto a small room which served to connect two corridors, one to the left, and one to the right. As we were now beneath the hareem, I imagined one corridor or the other must lead to the treasure house. While thinking which to try first, a sharp tapping sound came from some distance away down the corridor on the right-hand side: three taps, followed by a short silence, and then three more.

Wazim heard them, too, and pulled on my sleeve. 'Someone is down here,3 he whispered desperately. 'They will find us if we stay any longer.'

'Stay close,' I said, and started down the corridor. It was a low, vaulted passage of brick and stone; I held the torch before me and crept quietly along, listening to the rhythmic tapping which grew louder the further we advanced. A line of small openings ran along the top portion of the tunnel; no larger than a man's hand, I could feel cool air moving through these openings as I crept past.

The passage ended a few score paces along, joining another, larger tunnel, which angled sharply down. The tapping sound was louder here, and I could hear something else-it sounded like voices, but too muffled and indistinct to make out what they were saying. Drawn on by these sounds, I descended the passageway, Wazim trembling behind me, tugging insistently at my sleeve and urging me away with every step.

We soon arrived at another juncture; I could see it for the faint flickering of torchlight on the brickwork several score paces directly ahead of me. The rhythmic tapping had become a steady thudding pound, punctuated by grunts and mutterings.

'Stay here,' I said. Handing the torch to Wazim, I slipped the strap on the bundle of papyri from my shoulder and handed that to him as well. 'I will see what is ahead.'

He made to object, but I waved him to silence, and pointed to the spot on the ground where he was to plant himself, and then crept forwards alone. As I neared the end, I could see that a heavy iron grate sealed the opening. I lay down and squirmed forwards the last few paces on my stomach and, looking between the thick bars of the grate, peered around the corner and into the adjoining corridor beyond.

By the smudgy light of half a dozen torches scattered around them on the ground, two men with short axes were hacking at a timber door. The door, however, was bound with thick iron bands and was resisting their best efforts. The men were Arabs, dressed in black with dark brown turbans, and were unlike any I had ever seen among the caliph's soldiers or bodyguard. Their determined expressions and relentless hammering gave me to know that I had indeed found the treasure house.

I edged back from the grate and was about to withdraw until I could devise a plan for getting rid of my unwanted fellow thieves, when someone called out. The two stopped working and for a moment the passage became silent. Curious, I crawled back to the grating. The two had downed their axes and were talking to someone who had joined them. The third man remained out of sight beyond the edge of the corridor, and although I could not see who it might be, something about the sound of the voice held me.