In this extensive and hitherto unprecedented social transformation the old forms of handicraft disappear: whole sections of society, which are the representatives of the disappearing forms of handicraft, sink into poverty, and augment the class of proletarians. The progress of the industrial revolution extends also to agriculture: the greed for surplus value (ground rent) leads to enclosure of common lands by the great landlords, the independent yeomanry is decimated, the small proprietor and small tenant are made proletarians. A transmutation of social classes takes place; the urban population grows rapidly, the country districts are depopulated: out of the revolutionary process the outlines of two classes become more and more distinct: Capitalist and Proletarian. Both the factory proletariat and the other social sections which adopt a hostile attitude towards Capitalism react against the health-destroying exploitation, and struggle for a normal working day. The working time is curtailed and bounds are set to the efforts of the capitalist to lengthen the working day and obtain surplus value, but soon the progress of machine technique compels the worker to labour more intensely in the shorter working time: the accelerated movement of the machine determines the pace and necessitates a sharper straining of the nerves. Henceforth, the worker must compress into a working hour as much effort as was previously expended in an hour and a half. The surplus value which is extracted in this way Marx calls "relative surplus value." The struggle of the workers to secure a shorter working day is a powerful incentive to the manufacturers to perfect their machinery, in order to increase the amount of relative surplus value. The intensification of work or the creation of relative surplus value is one of the most immediate effects and one of the most striking features of advanced Capitalism. The understanding of this new phase is a preliminary condition to the comprehension of the Marxian system. In this matter, Marx goes considerably beyond the anti-capitalist theoreticians who followed upon Ricardo. What happens when the capitalist observes that the extraction of absolute surplus value comes up against an insurmountable obstacle? He sets himself to fit up his enterprise with the newest and most costly machinery, in order to supplant living labour-power and to work more intensively the living labour-power which he employs.