One might attempt to circumvent this difficulty in the following way: Far from being over-production, the 500 II c which are kept in stock by the capitalists and cannot be immediately converted into productive capital represent, on the contrary, a necessary element of reproduction, which we have so far neglected. We have seen that a money-supply must be accumulated at many points, hence money must be withdrawn from circulation, partly for the purpose of making it possible to form new money-capital in I, and partly to hold fast temporarily the value of the gradually depreciating fixed capital in the form of money. But since we placed all money and commodities from the very start exclusively into the hands of capitalists I and II when we drew up our scheme and since neither merchants, nor money-changers, nor bankers, nor merely consuming and not directly producing classes exist here, it follows that the constant formation of commodity stores in the hands of their respective producers is here indispensable to keep the machinery of reproduction going. The 500 II c held in stock by capitalists II therefore represent the commodity-supply of articles of consumption which ensures the continuity of the process of consumption implied in reproduction, here meaning the passage of one year to the next. The consumption-fund, which is as yet in the hands of its sellers who are at the same time its producers, cannot fall one year to the point of zero in order to begin the next with zero, any more than such a thing can take place in the transition from today to tomorrow. Since such supplies of commodities must constantly be built up anew, though varying in volume, our capitalist producers II must have a reserve money-capital, which enables them to continue their process of production although one portion of their productive capital is temporarily tied up in the shape of commodities. Our assumption is that they combine the whole business of trading with that of producing. Hence they must also have at their disposal the additional money-capital, which is in the hands of the merchants when the individual functions in the process of reproduction are separated and distributed among the various kinds of capitalists.