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[68] Herbert Croly: The Promise of American Life. By courtesy of the publishers, The Macmillan Company, New York City.
[69] From Scribner's Magazine, September, 1917. By courtesy of the publishers, Charles Scribner's Sons, New York City. Copyright, 1917.
[70] Thomas W. Corbin: Engineering of To-day. By courtesy of the publishers, Seeley, Service & Co., London.
[71] Thomas R. Lounsbury: English Spelling and Spelling Reform. By courtesy of the publishers, Harper & Brothers, New York City. Copyright.
[72] Gissing: The Private Papers of Henry Ryecroft, "Winter." By permission of the publishers, E. P. Dutton & Co., New York.
[73] George Gissing: The Private Papers of Henry Ryecroft, "Summer." By permission of the publishers, E. P. Dutton & Co., New York.
[74] Eustace M. Weston: Rock Drills. By courtesy of the publishers, McGraw-Hill Publishing Company.
[75] Gustav Pollak: Fifty Years of American Idealism. Houghton Mifflin Company. By courtesy of The Nation.
[76] George Gissing: The Private Papers of Henry Ryecroft, "Winter." By permission of the publishers, E. P. Dutton & Co., New York City.