Why Did Working Hours Increase in Eighteenth-Century London? Labour Supply Decisions and Consumer Durables During the Industrial Revolution Hans-Joachim Voth Clare College, Cambridge and Nuffield College, Oxford Abstract This paper analyses why hours of work increased in London between 1750 and 1800. On the basis of a new technique, changes in labour input are described. The main part of the paper uses the data gathered from witnesses' accounts to evaluate a number of competing hypotheses. The main part of the large rise in annual working hours, it is argued, can be attributed to the increased availability of consumer durables.