Tabla de Contenidos: “…7 The Academy Marks Its Semicentennial -- ALEXANDER AGASSIZ (1901-1907) -- State of Science at the Turn of the Century -- Academy Efforts on Behalf of the Metric System -- Efforts for the Extension of Forest Conservation -- Academy Report on the Philippines -- New Fields in Academy Membership -- Hale and International Cooperation -- IRA REMSEN (1907-1913) -- The Committee on Scientific Work under the Government -- The National Conservation Commission -- Preoccupation with Internal Affairs -- Steps Toward an "Academy Home -- Plans for a Commemorative History -- The Semicentennial Anniversary -- Hale's Vision for the Future -- 8 World War I and the Creation of the National Research Council -- WILLIAM HENRY WELCH (1913-1917) -- Government Requests to the Academy -- Organization and Staffing of the National Research Council -- Resignation of Welch and Election of Walcott -- CHARLES DOOLITTLE WALCOTT (1917-1923) -- The Academy and the Wartime Research Council -- Funding of the Academy's War Effort -- Military Research Problems -- Postwar Plans -- The Executive Order of 1918 -- The Carnegie Corporation Grant -- National Research Fellowships -- International Research Council -- 9 The Research Council's Permanent Status and the Academy's New Home -- Postwar Organization of the Research Council -- NRC Policy, Procedures, and Relation to the Academy -- Activities of the Research Council -- The Academy Acquires a Home -- 10 The Twenties: New Horizons in Science -- ALBERT ABRAHAM MICHELSON (1923-1927) -- Relations between the Academy and the National Research Council -- Engineering and Industrial Research -- Pioneering in the Field of Conservation -- Efforts on Behalf of Basic Research -- The Committee on Government Problems -- THOMAS HUNT MORGAN (1927-1931) -- The Committee on Oceanography -- Weather Forecasting -- Efforts Toward Calendar Reform…”