I place a block of wood on either side of the tube so it can’t move. This is the most commonly repeated piece of advice from my pocketbook. Any sudden shock could set this thing off; if I let it drop on to the floor, it’s likely to be the last thing I ever do. Looking through the little hole, I can just about make out the stash of tiny pink balls inside. Three thousand match heads, give or take. The contents of sixty-five packets of Swan Vestas, minus the superfluous wooden sticks. Not all bought from the same place, or on the same day. Obviously.

It confused me at first: you light one match and all you get is a flame. Light two together, or three, or ten, and you still only get a flame, it’s just bigger. It took me a while to work it out – getting a massive explosion is not just about the matches at all. It’s about where they are. It’s because they’re so tightly caged. All those bursts of heat, all in that same place – they have to escape somehow. But they’re shrouded in steel, each single ignition stacked on top of the last. Those little flares, almost harmless individually, if they’re given the space and time to burn out, are instead rammed together, held captive until they have no choice but to destroy everything that holds them back.

I reach into my pocket and fumble for the last piece of ammunition, gifted to me sometime during the night. Make that three thousand and one match heads.

I walk to the bench on the opposite side of the shed, sticking to the procedure I’ve followed throughout the project. Sometimes just the friction of slicing the match head off with wire-cutters is enough to spark one into life. So I cut them well away from those already prepared. ‘You don’t go pissing on the live rail,’ as Gramps is fond of saying. My fingertips are vibrating so violently that I struggle to drop the tiny ball into the tube. There’s a trick I learned from Miss Morgan, my piano teacher. If my hands were shaking before a big performance, she’d tell me to clap them together as hard as I could. I do just that, so hard they sting, and am amazed as always that it really does work.

‘Should you opt for an electrical detonator, you would be well advised to connect it to the explosive as late as is reasonably possible, for the avoidance of accidental deployment and injury.’