Understanding Capital Volume II, John Fox, 1985

Chapter 12: The Working Period

"[W]hen we speak of a working period we mean the number of connected working-days required in a certain branch of industry for the manufacture of a finished product." (p. 234 [308])

Different products require labor processes of varying duration to produce finished commodities ready for market. The length of the labor process required to produce a finished product is termed the working period. Marx uses the spinning of cotton yarn as an example of a commodity with a brief working period, for the product is ready for sale at short intervals; he uses the production of railroad locomotives as an illustration of a commodity with a very long working period.

Even when other factors (e.g., the proportions of fixed and circulating capital) are held constant, the length of the working period affects the capitalist's outlay for circulating capital. The amount of fixed capital advanced, however, is not affected by variations in the length of the working period. When the working period is long, the capitalist must continue to advance circulating capital for wages and for raw materials until the commodity is finished and sold, at which point the circulating capital returns in money form. Fixed capital, by definition, is advanced for more than one working period. With a long working period, therefore, the capitalist needs to advance no more fixed capital, although the wear and tear on fixed capital is recovered only when the product is finished and sold.

Because the required outlay of circulating capital depends upon the length of the working period, it is in the capitalist's interest to reduce this period. Increases in the productivity of labor (brought about, for example, by institution of a division of labor in the workplace, or by improving the instruments of labor) serve to decrease the working period. Often such a decrease is achieved at the expense of increased outlay for fixed capital (e.g., for machinery).

The length of the working period may also be decreased simply by increasing the scale of production; for example, twice as many workers may harvest a field in half the time. Here a general increase in the size of advanced capital is required.