Quit of these three sources of misconception, the reader will have little farther difficulty in apprehending the real nature of Effectual value. He may, however, at first not without surprise, perceive the consequences involved in the acceptance of our definition. For if the actual existence of wealth be dependent on the power of its possessor, it follows that the sum of wealth held by the nation, instead of being constant or calculable, varies hourly, nay, momentarily, with the number and character of its holders; and that in changing hands, it changes in quantity. And farther, since the worth of the currency is proportioned to the sum of material wealth which it represents, if the sum of the wealth changes, the worth of the currency changes. And thus both the sum of the property, and power of the currency, of the State, vary momentarily, as the character and number of the holders. And not only so, but a different rate and manner of variation is caused by the character of the holders of different kinds of wealth. The transitions of value caused by the character of the holders of land differ in mode from those caused by character in holders of works of art; and these again from those caused by character in holders of machinery or other working capital. But we cannot examine these special phenomena of any kind of wealth until we have a clear idea of the way in which true currency expresses them; and of the resulting modes in which the cost and price of any article are related to its value. To obtain this we must approach the subject in its first elements.