This double standard for gold is at first sight somewhat strange until we observe that the two systems are in complete harmony. For the gold piece of 168 grs. is nothing more than 1⅓ of the light shekel (168 ÷ ⁴⁄₃ = 126 grs.). The third of the light shekel (42 grs.) is the fourth of the Babylonian of 168 grs. There can be no doubt that the coins of 168 grs. were simply an experiment suggested by the coincidence that the number of grains (168) in the Babylonian silver shekel was exactly one-quarter more than those in the _light_ gold shekel, in the hope doubtless of obtaining a single standard for gold electrum and silver. The division of the silver stater into thirds would facilitate the process of exchange, as 13 silver staters and one-third would be equivalent to the gold piece of the same Babylonian standard, whilst 10 silver staters would be equivalent to one of the old electrum pieces of 168 grs. It is at all events certain that the standard of 168 grs. was not a regular gold unit, for it simply makes its appearance for a brief space, there being no trace of it at any earlier period, nor does it afterwards appear save in its own legitimate province of silver. A perfectly analogous case is that of the gold pieces struck by the Ptolemaic kings, who, starting with the gold stater of Philip and Alexander and the Phoenician standard for silver (after the founder of the dynasty had for a short time used the so-called Rhodian standard), presently struck gold pieces on the same standard as their silver. But the experiment of Croesus, if such it was, did not succeed. For the eastern mind was still too much impressed with the necessity of cleaving fast to the original weight unit obtained from the ancient unit of barter. For whether the attempt had failed before the reign of Croesus was brought to a sudden end by the conquests of the great Cyrus, or whether he continued up to the very hour of the Persian conquest to coin, at least for one part of his dominions, the gold pieces of the Babylonian silver standard, it matters little. As we have no evidence on the point, we cannot say whether there were two gold minae and two gold talents in use, one being of course the ordinary gold talent (called Euboic) of 3000 light shekels of 130 grs., the other containing 3000 shekels of 168 grs. each. The probability I think is that only the former existed. As 50 of the latter shekels made 1⅓ minae, there was no practical difficulty in making any calculations; on the other hand, if there had been two separate minae, and two separate talents, it would have led to great complications. The fact that we hear nothing about any such second gold system existing in Asia, and that when Darius fixed the tribute from each region he did not make it the basis of his payment, which he would probably have done as he would thus have made a considerable gain, by causing the payments in gold as well as those in silver to be made on the