that the primary cause of economic depressions was not land speculation, but rather constriction of the money supply. Walker also criticized George's assumptions that technical progress was always labor saving and whether land held for speculation was unproductive or inefficient. Bimetallism In August 1878, Walker represented the United States at the third International Monetary Conference in Paris while also attending the 1878 Exposition. Not only were the attempts by the United States to re-establish an international silver standard defeated, but Walker also had to scramble to complete the report on the Exposition in only four days. Although he returned to the U.S. in October disheartened by the failure of the conference and exhausted by his obligations at the Exposition, the trip had secured Walker a commanding national and international reputation. Walker published International Bimetallism in 1896 roundly critiquing the demonetization of silver out of political pressure and the impact of this change on prices and profits as well as worker employment and wages. Walker's reputation and position on the issue isolated him among public figures and made him a target in the press. The book was published in the midst of the 1896 presidential election pitting populist "silver" candidate William Jennings Bryan against the capitalist "gold" candidate William McKinley and the competing interpretations of the nation's leading economist's stance on the issue became a political football during the campaign. The presidential candidate and economist were not close allies as Walker advocated a double standard by all leading financial nations while Bryan argued for the United States' unilateral shift to a silver standard. The rift was heightened by the east-west divide on the issue as well as Walker's general distaste for political populism; Walker's position was supported by conservative bankers and statesmen like Henry Lee Higginson, George F. Hoar, John M. Forbes, and Henry Cabot Lodge. Other interests Political Economy, the first edition published in 1883, was one of the most widely used textbooks of the 19th century as a component of the American Science Series. Robert Solow criticized the third edition (1888) for being devoid of facts, figures, and mostly full of off-the-cuff judgments on the practices and capacities of Native Americans and immigrants, but generally embodying the state of the art of economics at the time. Walker also took an interest in demographics later in his career, particularly towards the issues of immigration and birth rates. He published The