Did working hours in England increase as a result of the Industrial Revolution? Marx said so, and so did E. P. Thompson; but where was the evidence to support this belief? Literary sources are difficult to interpret, wage books are few and hardly representative, and clergymen writing about the sloth of their flock did little to validate their complaints. In this important and innovative study Hans-Joachim Voth for the first time provides rigorously analysed statistical data. He calls more than 2,800 witnesses to the bar of history to answer the question: 'what were you doing at the time of the crime?'. Using these court records, he is able to build six datasets for both rural and urban areas over the period 1750 to 1830 to reconstruct patterns of leisure and labour. Dr Voth is able to show that over this period England did indeed begin to work harder - much harder. By the 1830s, both London and the northern counties of England had experienced a considerable increase- about 20 per cent - in annual working hours. What drove the change was not longer hours per day, but the demise of 'St Monday' and a plethora of religious and political festivals.