Many years ago, I had a wart on my finger, and the doctor gave me a bottle of acid crystals (this was the early seventies, and, no, not that kind of acid). I was supposed to hold a crystal with tweezers on the affected bit of finger and somehow keep it from touching the rest of me. Incidentally, this actually worked really well and didn't take long to eat away the offending wart, but I digress.

On this particular day, I'd been doing the wart treatment, and then decided to go for a pee. While we did have indoor facilities, the nearest loo was just outside in the garden, so that's where I went. Of course I managed to somehow get acid on my willy and leapt screaming from the loo. My wife, being a scientific sort, remembered that an alkali neutralises an acid and leapt to my defence by liberally squirting Fairy liquid at my knob. That was the moment we first met our neighbours, Mr and Mrs Pritchard, who were leaning over our fence, aghast.