On several occasions between 1920 and 1926, Keynes worked at a history of ancient currencies. In his correspondence with Lydia in 1924 and 1925–6, he reported that bursts of work on the subject kept him from working on his Treatise on Money.

Although subsequent research has meant that many of the details of Keynes's story require revision, the fragments which emerged from his research are of sufficient interest in themselves to merit publication, for they show Keynes turning his mind in an unexpected direction.

From Keynes's efforts over the period, the first surviving fragment dates from 1920.

NOTE ON THE MONETARY REFORM OF SOLON

According to Professor Gardner's interpretation of the authorities, Androtion makes out Solon's reform to consist in a change from the Aeginetan drachma (proportion 73 to 100), whereas according to Aristotle, Solon's change was from the Aeginetan drachma to the Euboic drachma (proportion 70 to 100). Professor Gardner thinks that the account of Aristotle is the correct one. He believes, therefore, that Solon changed the standard from the Aeginetan to the Euboic and that the change from the Euboic to the Attic was effected by Peisistratus fifty years later. I have not seen any direct evidence of the supposed further change of standard under Peisistratus.

I suggest that Professor Gardner has misunderstood Aristotle's statement and that there is in substance no contradiction between the statement of Androtion and that of Aristotle.