In those days, the only blacks in Dublin I knew of were Phil Lynott and me

The majority of passengers on the 77 bus had obviously never seen a black person before. It was the early 1990s, after all, and the economic boom with its migrant workers hadn't yet happened in Dublin. So as I got on the bus, the colour of the inside of a chimney, I got quite a few frank stares. I decided against smiling back, in case anyone was permanently blinded.

An hour earlier, I had been standing in a railway siding near Heuston Station having a heated discussion about responsibility with a young, but burly lorry-driver. I had waterproofs and a pair of Wellington boots on, and my official notebook and biro were secreted about my person in an out-of-the-way place.

"It isn't worth it," he said. "I've seen it before. It just can't be done."

"Nonsense." I said in my most imperious tones. "I've been told to clean every container before it goes on the train and that's what I'm going to do."

He grumbled and got back into the tractor unit, speeding around the yard among the piles of 40-foot boxes awaiting loading. He screeched the lorry to a halt near the hut that housed my power washer and hopped down from the cab.

I opened the back of the container and peered inside. It was completely empty except for some dust. There had been a delivery of some sort to a tyre company by articulated lorry and this, the empty trailer part, was on its way to Waterford for re-assignment to another delivery. Before the crane took it on board the stack, or dropped it skillfully onto a flatcar on the waiting train, I was going to wash it out.

A small crowd of interested truckers and office staff was gathering. The driver was telling them what I was up to. Somebody sniggered.

I climbed up into the cavernous container and walked to the far end, dragging the gun of the steam cleaner and its long hose behind me. I aimed the miniature water cannon at the ceiling and fired. A burst of hot water and steam flew upwards and disappeared in a cloud of black carbon. Puzzled, I tried a different tack, aiming at the floor. This had a slightly more predictable result. Mahogony floorboards began to appear out of the blackness.

Unknown to me, on the first burst of steam the incredibly fine carbon powder waste coating the inside of the container had bonded to the water vapour and had formed into dense black clouds that billowed out the open doors at the assembled onlookers, who turned to flee, dropping rolled up tabloids, tea mugs and delivery dockets in confusion. I tootled on regardless, until, twenty minutes later, I had to admit defeat. No matter how much I tried, I couldn't shift the carbon, which had a perculiar, life-like quality of avoiding my gun and which absolutely refused to yield to furious brushing.

Finally, I hopped down from the container, wondering where everybody had gone. I slammed the doors in defeat. There'd be no plastic seal put on this one.

"No," I'd say, if asked. "I didn't see that box at all. Must have gone through when I was on a break. Sorry about that."

I walked over to the hut and looked in the mirror. Someone started singing "Old Man River"...

I tried to scrub it off, but it just got worse. Once water was added, the carbon turned into a kind of paint-like substance that just clung onto the skin. In the end, I just had to stay that way until I could get home and climb into a proper bath.

It's a long walk from Heuston Station to O'Connell Bridge. All the longer when you're trying to bluff it like a tough twenty-something working man and are painted completely black. A tramp outside the Mission moved out of the way in case I dirtied him.

It was after 5.00pm and the bus was packed. I still had a seat to myself though, all the way home.

We won't even talk about the day the man brought the container from a flour delivery down to the siding. I ain't kidding.