In the 19th century, over half of the world's supply of which product was produced in the UK?

Okay, let's unravel the story behind Britain's dominance in the 19th-century cotton cloth industry. Think back to the Industrial Revolution, which really kicked off in Britain. One of the key inventions was the spinning jenny, which dramatically sped up the process of turning raw cotton into thread. This, along with other innovations like the power loom, meant that British factories could produce cotton cloth on a massive scale, far outpacing other countries. Raw cotton was imported from places like America and India, processed in mills primarily located in the north of England, and then the finished cloth was exported all over the world. By the mid-19th century, Britain was the world's leading manufacturer of cotton cloth, accounting for over half of the global supply. While Britain certainly produced beer and, later, cigarettes, and imported rubber, none of these industries reached the same level of global dominance as cotton cloth manufacturing during that period. The sheer scale of the British textile industry at the time is what makes cotton cloth the correct answer.