There’s a Cartier jewellery exhibition on at the V&A in London at the moment. On my shelves I have this very good biography of the Cartiers, but one of my favourite stories in the book is about flying machine pioneer Alberto Santos-Dumont. He would fly his hydrogen-filled rugby-ball-shaped air vehicle along the streets of Paris.

The book says: “The famous competition involved flying eleven miles from Paris's Parc de Saint-Cloud to the Eiffel Tower and back again in under thirty minutes. One of Santos's early attempts in the summer of 190I had almost ended in disaster when his dirigible started to lose hydrogen. Much to the horror of his adoring fans looking up at him from the pavements below, Santos had crashed into the side of the Hôtel Trocadéro and had to be rescued by the fire brigade. Fortunately, he had survived unscathed, but his dirigible was declared irreparable. Santos immediately ordered the construction of a new machine so he could try again, and by autumn that same year, he had succeeded. The problem this time, though, as he explained to Louis, was that the Deutsch de la Meurthe was a race against time, and yet it was impossible to check his time while flying. Looking at his pocket watch required taking his hands off the controls. He simply couldn't risk that, not after the last crash.
Cartier's pocket watches were popular among fashionable men in the French capital. Flat and well proportioned, they fit smoothly into one's waistcoat and felt reassuringly solid in one's hand. But as Louis considered his friend's predicament, he started to imagine something just as stylish but even more practical. If he were to combine a smaller watch face with some kind of elegant built-in wrist strap, Santos wouldn't need to move his hands from the flying machine's controls.”

And that’s how the wristwatch was invented.