I have always wondered, often angrily, why answering the calls of nature is such a humiliating, if not excruciating experience.

Camping, which is what we are doing now, forces one to the brink of the infamous "pit toilet", which anywhere hot has a unique, breathtaking, pore-tightening malodorousness, unless you approach it, shuddering, before the sun comes up. Strangely enough, everyone else on the campsite always appears to have uncontrollable diarrhoea. One sits, breathing as little as possible, conscious of a regular to-ing and fro-ing of plump flies behind one's back. The door to the rather small building (I regularly bump my head on dangerously-projecting objects in pit toilets) never locks shut, so the sitter tenses at every crunch of gravel outside. At night one risks dropping one's flashlight into its murky depths. And there are our wonderful fellow campers who empty everything they don't want, including the contents of their RV toilets, into the long-suffering pit...

But at least a pit toilet is a natural byproduct of the uneasy relationship between humans and waste disposal. And no-one can possibly remain in a pit toilet long enough to scribble even the shortest rude word on the wall. What we do to other loos isn't so easily forgivable.

I know that ever since gents' public toilets were invented (well before the Romans, I presume), they have stimulated the creativity of a peculiar group of humans with very little knowledge of both their own and female anatomy, but great interest in both. But I would have thought that over a couple of thousand years of civilization the practice of writing on loo walls and systematically attempting to destroy them would have died out, along with pillaging or disembowelling. But no.

I often sit on public transport and stare at the apparently-respectable men around me and wonder which of them are murderers, which are pedophiles, which are wearing ladies underwear, and which are carrying felt tip pens, pencils and penknives in readiness for their next attack on some innocent lavatory wall.

I also sometimes wonder at the standard of teaching of biology, having been forced to examine so many incorrect gynaecological (and urological) diagrams. I wonder what the loos are like in medical schools?

When I watch the crew of SS Enterprise walking down the endless corridors of their starship I wonder if the gents they have just passed has graffiti on its walls.

But while graffiti is harmless enough, and occasionally interesting, what makes me really puzzled and angry is the systematic and cross-cultural habit of destroying public toilets.

I daily enter upon some battlefield which has been abandoned by its nominal authority. Apart from reams of unoriginal inscriptions, the doors have been rendered useless or even removed completely, the washbasins languish without water, let alone soap. My fellow "civilized" humans even appear not to understand that the little lever on the side of the cistern has to be pressed down in order to magically flush the loo (apparently this is true of "ladies" loos too).

Vandalism has been blamed on jealously. But there can be few males these days who don't have a toilet at home, prumably pristine, with a door that locks. So what is there to be resentful of? Everyone pees and shits, so the vandalism can't be blamed on some form of discrimination.

Unless a loo is patrolled by an old crone with a mop, it faces almost certain destruction. Why?

Hey, here's another strange North American thing -- why do you have such skimpy doors on your cubicles? Just as I don't wish to sit in the partial view of others, I have no desire to be presented with a row of crumpled trousers and assorted footwear whenever I venture into the lavatory.

And then there are the strange goings-on in public lavatories, about which I am going to remain non-judgemental except to tell my one experience of an odd, peculiar, and mysterious occurrence...

I well remember a public loo in Dover in which I was comfortably esconced one morning, at peace with the world, when I noticed an EYE, large and pale and watery, on the other side of a neatly-bored hole in the cubicle wall... It blinked twice in the few seconds it took me to get out of there!

It saddens me that the human race has not progressed very far since the first Homo habilis scratched an improbable phallus on the wall of a smelly cave....

This makes me so mad I could kick in a loo door!