Museum of Vertebrate Zoölogy, University of California, began 5-year field study of animal life in Yosemite, which culminated in publication of 752-page treatise. Grinnell and Storer; YNHA, 1924, p. 2. John Muir died in a Los Angeles hospital, December 24. Badè, 1923-1924, II, pp. 390-391. 1915 Parsons Lodge built by Sierra Club in Tuolumne Meadows. SCB, 1916, pp. 84-85. First appropriation for the John Muir Trail approved by Governor Johnson. Rensch, 1933, p. 484; Wolfe, 1945, p. 364. Yosemite Lodge established in Yosemite Valley. Tresidder, D. B., p. 37. Stephen T. Mather purchased Tioga Road and presented it to U. S. Government. Farquhar, 1926, p. 94. Mather became assistant to Franklin K. Lane, Secretary of the Interior. Albright, 1929, pp. 10-11; Cramton, 1929, p. 13. Yosemite horse-drawn stages replaced by motor stages. Tresidder, D. B., p. 33. R. B. Marshall made superintendent of all national parks. USNPS, 1916, p. 5. 1916 National Park Service Act passed August 25. Stephen T. Mather made Director. USNPS, 1916, p. 81; 1917, p. 1; Farquhar, 1926, p. 63. W. B. Lewis made Superintendent of Yosemite National Park. USNPS, 1916; Farquhar, 1926, p. 114. Tuolumne Meadows Lodge installed; also Tenaya and Merced camps opened. Tresidder, D. B., p. 76. 1917 Stephen T. Mather became first Director, National Park Service. Albright, 1929, p. 12; Cramton, 1929, p. 13. Glacier Point Hotel completed. USNPS, 1917, p. 59; Tresidder, D. B., p. 61. Wawona Road and Glacier Point Branch turned over to federal government. USNPS, 1917, p. 62. Parts of park opened to grazing. USNPS, 1917, p. 153. Modern school buildings constructed. USNPS, 1920, p. 237. David A. Curry dies; Mrs. Curry continues operation of Camp Curry. Tresidder, Mary C., MS. 1918 Cascade power plant completed at cost of $215,000. USNPS, 1917, pp. 61, 143; 1918. pp. 45, 134. Ledge Trail built. USNPS, 1918, p. 47. 1919 First airplane landed in Yosemite Valley, May 27. Lt. J. S. Krull, pilot, alone. USNPS, 1919, pp. 183, 190. LeConte Memorial Lectures instituted. USNPS, 1919, p. 194. 1920 Construction started on all-year highway up Merced Canyon. USNPS, 1920, p. 110. Rangers’ Club House built. USNPS, 1920, pp. 113, 250. Yosemite National Park Co. founded. USNPS, 1920, p. 248. Yosemite educational work started by H. C. Bryant, A. F. Hall, L. H. Miller, and Enid Michael. Yosemite Museum planned. USNPS, 1920, pp. 113, 245, 253; Hall, 1930; YNHA, 1932, pp. 2-3. California valley elk brought to Yosemite. USNPS, 1920, p. 250; 1921, p. 196. Big Trees Lodge built at Mariposa Grove. Tresidder, D. B., p. 72.