the town's rapid expansion and commitment to industrialisation resulted in social instability. in the early 19th century, dewsbury was a centre of luddite opposition to mechanisation in which workers retaliated against the mill owners who installed textile machinery and smashed the machines which threatened their way of life. in the 1830s, dewsbury was a centre of chartist agitation. in august 1838, after a speech by chartist leader feargus o'connor, a mob of between five and seven thousand people besieged the dewsbury poor law guardians in the town's royal hotel. the mob was dispersed by troops. trouble flared in 1840 when radical agitators seized control of the town, and troops were stationed to maintain order. this radical tradition left a legacy in the town's political life, its first elected mp in 1867 was john simon, a jewish lawyer from jamaica and a liberal. the tradition of firing the "ten o'clock" gun dates from 1815 and was a hangover from the luddite problems. it was fired from wormald and walker's mill to reassure that all was well. it could be heard all over the area. eventually the actual gun was replaced with a specially made firework but the tradition was discontinued in 1983 with the closure of the mill.