In the following chapters Marx enters into an elaborate and exhaustive analysis of the rate of surplus-value, i.e. of the rate at which the creation of surplus-value takes place; and he also deals with the important subject of the duration of the working-day. But as this 1s after all a matter of detail, in spite of its 259 very great interest and importance we must omit it, as it would carry us beyond the scope of this chapter.
Marx distinguishes between absolute and relative “surplus-value”; the absolute being the product of a day’s labour over and above the necessary subsistence of the workman, whatever the time necessary for the production of a definite amount of product may be. The relative “surplus-value,” on the other hand, is determined by the increased productivity of labour caused by new inventions, machinery, increased skill, either in manipulation or the organisation of labour, by which the time necessary for the production of the labourer’s means of subsistence may be indefinitely shortened.
It will be seen once again from all this, that whatever instruments may be put into