¹⁵⁹ _Elementary Principles of Economics_, 1912, pp. 228–29. In the illustrations given by Prof. Fisher he appears, although he does not mean it, to make the success or failure of bimetallism hang upon the question whether or not the two metals are maintained in circulation. For in illustration which he gives to show the failure of bimetallism—Fig. 14 (b)—his film _f_ shows gold to be entirely thrown out of circulation; while in the illustration he gives to show the success of bimetallism—Fig. 15 (b)—his film _f_ shows gold to be only partially thrown out of circulation. But there seems to be no reason to suppose that there cannot be a third possibility, namely, that while the position of the film _f_ is as in Fig. 14 (b) the level of the gold bullion and silver bullion may be as in Fig. 15 (b)—a possibility in which bimetallism succeeds although one of the two metals is entirely pushed out of circulation. For the success of bimetallism it is not necessary that both the metals should remain in circulation. Its success depends upon whether or not the compensatory action succeeds in restoring the relative values of the two bullions to that legally established between the two coins. If it succeeds in achieving that, the ratio would be preserved even if the compensatory action drives one metal entirely out of circulation. Under which of these two possibilities could the circumstances arising after 1873 have fallen? That is a question about which no one can say anything definitely. Even Jevons, who admitted the success of the bimetallic law in the earlier period, was not very sanguine about its success in the latter period. It was he who observed¹⁶⁰ “that the question of bimetallism is one which does not admit of any precise and simple answer. It is essentially an indeterminate problem. It involves several variable quantities and many constant quantities, the latter being either inaccurately known or, in many cases, altogether unknown. …” ¹⁶⁰ _Investigations_, etc. (ed. Foxwell), p. 317.