Using Peel's figures London's inhabitants were each consuming 1.77 tons of coal per annum in 1866, in comparison with a prodigious 5.26 tons per capita in Manchester. If we take Robert Angus Smith's estimate of three million tons of coal consumed in the city by the 1870s and set this total against the 475,990 population of the two municipal boroughs of Manchester and Salford, we see a dramatic increase to 6.30 tons per capita. Roy Church has estimated that coal consumption in Britain as a whole saw a threefold increase between 1830 and 1913, when it slightly exceeded 4 tons per capita.36 Coal exports also rose from less than 2 per cent of British output in 1830 to about 10 percent in 1870, increasing to some 27 per cent in 1913.37 Most of Britain's expanding coal production was, then, still utilised at home. And Britain continued to consume more coal per capita than any other country in the world until 1905, when the United States recorded a higher figure. Chicago, one of the smokiest cities in the United States, consumed some 6.91 tons of coal per capita in 1910.3~

Taken as a whole, an analysis of the foregoing statistical data regarding coal production and coal consumption in the Manchester region shows a striking increase in the output and utilisation of coal in order to maintain and promote urban and industrial growth over the period. Cotton manufacturing was initially of crucial importance in bringing the new fuel technology into the city, with the large-scale application of steam power to various other branches of industry being introduced more slowly during the second half of the nineteenth century. By the end of the nineteenth century most businessmen in the twin cities employed coal-fuelled steam engines in their warehouses, textile factories, printing, iron, chemical, or engineering works: there were even steampowered laundries.39 In addition, most of Manchester's many thousands of householders had come to prefer to burn coal to obtain domestic heat and energy. Thus, as Manchester's businessmen and householders rarely used coal efficiently, the statistical evidence strongly suggests that the smoke cloud was gradually deepening throughout the period. First designated as a serious environmental problem by contemporaries in the city during the 1840s, by the time it was 're-discovered' by a second generation of reformers in the 1870s the 'smoke nuisance' had undoubtedly intensified. Even so, it must be emphasised that this was probably experienced as a cumulative escalation of the nuisance and not as a sudden, spectacular surge. Nonetheless, in the nineteenth century Manchester was one of the smokiest cities in the world.