The process of industrialization which gathered momentum in Britain during the second half of the eighteenth century and initiated the sustained upward movement of real incomes that the western world now takes for granted, involved revolutionary changes in the structure and organization of the economy. The origins of some of these changes can be traced to earlier centuries. Some of them are still working themselves out. It is generally agreed, however, that the crucial transformation occurred fairly rapidly—certainly within the century between 1750 and 1850, probably in a considerably shorter time. The temptation to time it narrowly, to identify a relatively short period of time within which the crucial change can be said to have taken place, is very strong. The discontinuities of history are more dramatic than its continuities, and it is natural to want to give them a precise time reference.

So the chronology of the industrial revolution has become a fruitful source of controversy. There are those who would like to trace its beginnings back to the beginnings of organized manufacturing industry itself and others who insist that it is not over yet, even for a fully industrialized country like Britain. There are those who find overwhelming evidence for significant discontinuity in the last quarter of the eighteenth century: and others like Clapham and Schumpeter who are equally convinced that ‘if one wishes to refer the industrial revolution to a definite historical epoch it can be located more justifiably in the second quarter of the nineteenth than in the end of the eighteenth century’.