In Class II, for the products of which wages, profit and rent are expended, in short, the revenues consumed, the product itself consists of three components so far as its value is concerned. One component is equal to the value of the constant portion of capital consumed in production; a second component is equal to the value of the variable advanced capital laid out in wages; finally, a third component is equal to the produced surplus-value, thus = profit + rent. The first component of the product of Class II, the value of the constant portion of capital, can be consumed neither by the capitalists of Class II, nor by the labourers of this class, nor by the landowners. It forms no part of their revenues, but must be replaced in kind and must be sold for this to occur. On the other hand, the other two components of this product are equal to the value of the revenues created in this class, = wages + profit + rent. In Class I the product consists of the same constituents, as regards form. But that part which here forms revenue, wages + profit + rent, in short, the variable portion of capital + surplus-value, is not consumed here in the natural form of products of this Class I, but in products of Class II. The value of the revenues of Class I must, therefore, be consumed in that portion of products of Class II which forms the constant capital of II to be replaced. The portion of the product of Class II which must replace its constant capital is consumed in its natural form by the labourers, capitalists and landlords of Class I. They spend their revenue for this product of II. On the other hand, the product of I, to the extent that it represents a revenue of Class I, is productively consumed in its natural form by Class II, whose constant capital it replaces in kind. Finally, the used-up constant portion of capital of Class I is replaced out of the very products of this class, which consist precisely of means of labour, raw and auxiliary materials, etc., partly through exchange by capitalists of I among themselves, partly so that some of these capitalists can directly use their own product once more as means of production.