You’ll never guess what vicars got up to in the 1800s… | Jack Marshall’s column

By 1851, there were 17,621 Anglican clergymen in Britain, all of whom had been to university and who enjoyed an annual income of £500 (about £55k today). But it was a time of dwindling church attendances – many clergymen weren’t even pious themselves, relying on a big book of sermons from which they read once a week. The rest of their time was their to do with as they pleased.

As Bill Bryson details in ‘At Home’, this created a strata of well-educated rich folk with time to indulge their interests. And guess what? They did some truly astonishing things.

Yorkshire’s George Baildon compiled the world’s first Icelandic dictionary, while Devon-based Jack Russell bred the dog which shares his name. In neighbouring Dorset, Octavius Pickard Cambridge became the world’s leading spider expert while Oxford’s William Buckland wrote the first scientific description of dinosaurs.

Somewhat less empirical but no less impressive, William Shepherd in Dorset wrote a history of dirty jokes just as his colleague George Garrett in Manchester was inventing the submarine. Yorkshire’s Sabine Baring-Gould not only wrote the hymn ‘Onward, Christian Soldiers’ but also penned the first novel featuring a werewolf.

Famous for his pink fez, Cornwall’s Robert Stephen Hawker whiled away a happy, opium-tinged life writing poetry admired by Alfred, Lord Tennyson. William Greenwell in Durham was a founding father of modern archaeology and invented a fishing fly for catching trout. Berkshire’s John McKenzie Bacon was a hot-air balloonist.

MJ Barkley in Northamptonshire became an authority on plant diseases, accidentally causing the first outbreak of powdery mildew, while Derbyshire’s John Mitchell devised a way to weigh the Earth. But the most impressive was Thomas Bayes of Tunbridge Wells.

Bayes created a mathematical equation to calculate probability distributions so complex it had no practical application without computers to do the sums. Now known as Bayes' theorem, it’s used to model climate change, stock markets, cancer rates, and cosmology. Not bad for a man who died before the War of Independence.