In a letter to the Gazette (XXV, February, 1941, p. 36) Mr. Siddons discussed my article in the Gazette for October 1940; he gave a method of long multiplication of money and suggested that I might carry out further tests using his method. I was at once attracted to Mr. Siddons’ method, and carried out some tests, though I was unable to make them as extensive or as exhaustive as I desired. The present article contains a report on these tests. No very definite conclusions can therefore be drawn. This record of the work done may, however, serve as a useful pointer for those who may be sufficiently interested to carry the investigations further. I should have been pleased to have done so myself but the circumstances of my professional life have altered somewhat since carrying out the investigations recorded in recent numbers of the Mathematical Gazette.