There's not all that much that George Washington, Denis Thatcher and Mrs Slocombe of Are You Being Served? have in common, but one thing binds them together as closely as if they were blood relations: the love of a good gin and tonic. And so, were they still with us, they would this weekend be marking, no doubt with due solemnity and reverence, the drink's 150th anniversary.
Gin and tonic is a cocktail, superficially of spirit and a fizzy diluent, but also of other, even more potent ingredients: the British enthusiasm for drunkenness, class and the Raj. First, the base – a grain-based spirit flavoured with juniper and herbs, which, until tonic was added, had a long, and almost entirely disreputable, history.
It began life in the Netherlands in the 16th century as a digestif, and spread to Britain, where, thanks to taxes on other drinks, it became the cheap route to alcoholic oblivion. William III encouraged the Army to consume the beverage of his native land (hence "Dutch courage"), and the highly sweetened version of the drink that evolved in Britain made it popular even among young children.
By 1750, London's 675,000 throats were swallowing 11 million gallons a year, with one household in four also producing the stuff.
Gradually, gin madness subsided, and the drink began – as the less-sweetened London Dry Gin – to move up the social scale. It had a special place in the affections of the officer class, especially in India, where malaria was a constant threat.
The antidote was quinine, a bitter substance from the bark of a South American evergreen, often taken with gin, and which, in 1858, one Erasmus Bond rendered in an acceptable form by inventing tonic water. Winston Churchill was in no doubt about the value of this breakthrough, saying: "Gin and tonic has saved more Englishmen's lives, and minds, than all the doctors in the Empire."
From the sub-continent, gin and Indian tonic water came back to London's clubland, and thence, via the cocktail culture of the Twenties, added a certain raffishness to its drinkers. The aspirational adopted it, a G&T became the tipple of the golf-club classes, and, gradually, it became more brassy than classy. Today, it hovers uncertainly in and out of fashion, but, because of its associations, it is ever the drink that is more than the mere sum of its nominal parts.