“The supply of such ore being inexhaustible the output depends upon the number and size of the mills employed to extract the gold. It is reasonably certain that, for years to come, the improvements in methods and processes of mining will more than keep pace with both the decline in the quality of the ore and the increase in the cost of mining due to rising prices and wages, occasioned by the depreciation of gold. “In view of all the facts, Mr. Selwyn-Brown’s conclusion that ‘a progressive increase each year may confidently be expected’ is conservative. This conclusion, is almost a certainty. The uncertainty lies in the possibility, if not probability, either of discovering many important new mines in the practically unexplored parts of every continent, or of making improvements that will radically reduce the cost of extracting gold. In either case the increase in the output of gold might be not simply arithmetically but geometrically progressive.” Admitting that the question of gold production is debatable, it remains for the future to develop any radical change, and it will be necessary for the student to decide this point for himself either by the light of facts as yet not established, or by accepting theories as yet not convincingly erected. If a change occurs, or may reasonably be expected, an understanding of the subject from the positive side of the question loses none of its value. The principles involved could be as successfully applied in reading the probable future by modifying or reversing effects, and reconciling them to a modification or reversal in the cause. If, for example, we accept the theory that increased gold production means advancing commodity prices, and find reason later to believe that gold production will cease to maintain its ratio of increase, we may alter our views accordingly so far as this single influence is concerned. _1--The effect of the increasing gold production on bonds and preferred stocks having a fixed rate of income._ In this division of the question the crux of the whole matter is interest on money. The question might, in fact, be stated thus: “What is the effect of increasing gold supply on money interest rates?” and having solved that problem, the original inquiry is answered.