A sudden spurt in the British population – fuelled by rising food production, which doubled between 1600 and 1800 – provided a market of workers and consumers. People poured into cities: between 1790 and 1850, the city dwellers more than doubled from 9.7 per cent to 22.6. By 1800, there were a million Londoners. In thirty years, that doubled; by the 1870s, it had doubled
