I gaped at him. What a fool I was! Certainly I was unfit to be an agent. I spoke airily of breaking in, but I had seen the size of that lock. Of course we would need tools of some sort.

Andrew slid an amused glance at me.

‘We’ll spy out the building first,’ he said, ‘then decide what we need. From the way you describe the lock, it will not be easy to pick, and I’ve little skill in the art, though my sergeant has.’

‘Should we fetch him from the camp?’

‘He’s still in England. Unfortunately.’ He jerked his head. ‘Down here, is it?’

We had reached the alleyway. ‘Aye,’ I said. ‘Down to the end and round the corner on the left, facing the canal.’

It was impenetrably dark in the alley and we had not yet lit the lantern, so that we could not avoid the noisome liquid which had spread even further than before, but when we emerged at the canal-side, the reflection of the sliver of moon off the water gave us light enough to see the hut and – all too clearly – the massive lock on the door. Andrew shook his head at the sight of it.

‘There’s no hope of breaking that, Kit, nor the door. It looks to be cross-planked in oak.’ He tried to get his fingers round the edge of the shutters which barred the window, but they too were made of thick oak boards.

‘I wonder–,’ I said.

‘Aye?’

‘Perhaps we could find our way through the back. The cottage round the corner in the alley, the one where Hans lived, is quite derelict. We could easily get in, but I cannot remember whether there was a way out at the back. If there is, it might be possible to approach this building from behind.’

‘Worth trying,’ he said, turning back at once.

Standing before the half-open door of the cottage, my nerve nearly failed. My reason tells me that ghosts do not exist, but it took every ounce of courage to enter that cottage in the dark, with the memory of that murdered man lying on the floor as vivid as if it were still there.

‘Best light that lamp,’ Andrew said.

I nodded, and fumbled with flint and tinder, for my hands were shaking. I had it alight at last, but shielded it from the street with my cloak as we crossed the threshold. It would be as well to avoid being seen.

The place was even more forlorn than I remember. The few sticks of furniture were gone, looted by other poor cottagers for their own houses or smashed for fuel during last winter’s cruel weather. There were a few shards of pottery lying beside the cold ashes on the hearthstone, and the floor spat and crunched under our feet with grit blown in from the street. There was a rustling in the battered thatch from nesting birds or mice, but living creatures did not frighten me. Once we were inside and Andrew had dragged the door as closed as possible on its sagging hinges, I raised the lantern and looked around. In front of me a patch of the beaten earth floor was stained a darker colour.

‘That was where he was lying,’ I whispered.

Andrew nodded absently, but this place held no horrors for him. He had walked over to a far dark corner where there was another door that I had not noticed before. He struggled to open it, but it would not move, either warped or blocked by something on the outside. He heaved with his shoulder, but still it would not budge. I joined him, holding the lantern out of harm’s way and together we threw ourselves against the door. It shivered and cracked apart, sending Andrew sprawling half inside and half outside, while I just managed to grab at the splintered frame before I fell on top of him.

He clambered to his feet, brushing away fragments of rotten wood and rubbing his knee, which had struck a large rock. It had been wedged against the door from the outside, intended to prevent its being opened. He took the lantern from me and held it up beyond the gap where the door had been. The flickering candlelight revealed a small yard enclosed on two sides by this cottage and the adjacent locked shed, and on the remaining two by the blank walls of two other houses. As we had hoped, there was a door into the other building from the yard.

Without speaking, I pointed across the yard, where a row of barrels stood, like those I had seen on the barge. Andrew nodded. He seemed to be searching the ground for something. There was a clutter of rubbish strewn about and he stepped out into the yard to examine it.

‘This might serve,’ he said softly, holding up a piece of bent metal. ‘Near enough to a crowbar.’

It hardly seemed necessary to keep our voices down. The noise we had made breaking down the cottage door must have been heard as far away as the church. I picked my way around the ruins of the door and walked over to the other building. This back door did not bear a vast lock like the front, but it was almost certainly bolted from the inside. I doubted whether Andrew’s makeshift crowbar would be sufficient to lever it open.

‘There is another window here,’ I said, hardly above a breath. ‘The shutters are old. I think we might be able to open them.’

He came up beside me.

‘Too small.’

‘I think I could get through.’

He sized me up with a quick glance. ‘Perhaps you could.’

It proved easier than we had hoped. Andrew set the lantern on the ground and inserted his metal bar under the bottom edge of the right-hand shutter. Almost at once it swung out, snapping the hook that had held it shut. Then he reached up and grabbed the second shutter, which swung out unresisting. I took off my bulky cloak and laid it on the ground next to the lantern.

‘Give me a leg up, then pass me the lantern.’

When I was sitting on the sill, with a leg on either side, I leaned toward the inside of the building and moved the lantern from side to side. Like Hans’s cottage, it consisted of just one room, but this room showed no sign of being lived in. It was stacked high, all along the wall to my right, with more of those long canvas bundles.

‘I’m going to take a closer look,’ I said, and dropped down inside, tripping over my wretched sword and falling flat on my face in the dirt. The lantern tipped crazily sideways, but I managed to right it. The candle flickered wildly, but did not go out.

The bundle on the top of the nearest stack was just a few feet away. I felt it all over with my left hand, still holding the lantern in my right. The contents seemed to be long tubes of metal, but I could not be sure. In irritation, I put down the lantern and tugged at the end of the canvas. One fold fell open and finally I could see what lay within.

I stumbled over to the window.

‘Aye,’ I hissed. ‘It’s muskets. Dozens of them.’

‘Do you think you can lift one of the bundles out of the window?’ I could not see him, but he must be just below the sill. ‘We need evidence.’

‘I think so.’

It was heavier than I thought, but I managed to drag one of the bundles to the outside wall. Raising it to the window was more difficult, but as it teetered on the sill I felt Andrew take the weight.

‘Better get out of there now,’ he whispered. ‘I thought I heard someone coming along the canal.’

I realised that this would be more difficult than climbing in, for there was no one to give me a leg-up. I could heard the approaching footsteps myself now. More than one man. I passed the lantern out of the window.

‘Douse it!’ I said. ‘The light may be visible through the cottage.’

One of the barrels, I thought. I could climb out by one of the barrels. I grabbed the nearest and started to roll it under the window. My hands were slippery with sweat and I kept losing my hold on it, but at last I had it in place. They might notice that it had been moved, but that was a risk I had to take.

Something troubled me. There had been an unmistakable stench over by the barrels. I realised that I had been half aware of it before, ever since climbing in, but had been too caught up in examining the guns to attend to it. My eyes had grown accustomed to the near dark of the room and while we had been here the quarter moon had climbed a little higher, throwing an oblique shaft of silver light through the window, just catching the edge of something in the corner beside the barrels. Torn between the need to escape and the anxiety to put to rest the fear that stench had awakened, I crossed quickly to the far wall and looked down.