“Here’s your G&T,” says my current visitor, Andrew. Surely one of the nicer sentences in the English language.

Tonic is a soft drink regarded with an evil eye here in Cairo as the locals are sure the only reason we foreigners want to drink it is to dilute our gin. So it’s not so easy to find. The foreign supermarkets sell it, but you’ll never find it in the Egyptian chains or in the fridges at the little kiosks at every street corner, which sell everything from water to phone cards, chocolates and cigarettes. All the essentials. I learned the lesson about tonic after I rolled into a little supermarket nearby and asked for tonic.

“Noooooo-ooo,” replied Ahmed behind the counter, waving his head like a bull with a fly in his ear. “We never sell tonic. Because you will mix it with alkoool.”

Ethical consumerism, it appears, is not yet dead.

My grandmother, who firmly swore by a diet of tonic water and natural yoghurt while travelling in foreign climes, would surely have turned in her grave.