This is no distinction without a difference. The difference is so marked that few indeed even of those who visit our national parks in a frivolous or merely recreational mood remain in that mood. The spirit of the great places brooks nothing short of silent reverence. I have seen men unconsciously lift their hats. The mind strips itself of affairs as one sheds a coat. It is the hour of the spirit. One returns to daily living with a springier step, a keener vision, and a broader horizon for having worshipped at the shrine of the Infinite. III The Pacific Coast Expositions of 1915 marked the beginning of the nation's acquaintance with its national parks. In fact, they were the occasion, if not the cause, of the movement for national parks development which found so quickly a country-wide response, and which is destined to results of large importance to individual and nation alike. Because thousands of those whom the expositions were expected to draw westward would avail of the opportunity to visit national parks, Secretary Lane, to whom the national parks suggested neglected opportunity requiring business experience to develop, induced Stephen T. Mather, a Chicago business man with mountain-top enthusiasms, to undertake their preparation for the unaccustomed throngs. Mr. Mather's vision embraced a correlated system of superlative scenic areas which should become the familiar playgrounds of the whole American people, a system which, if organized and administered with the efficiency of a great business, should even become, in time, the rendezvous of the sightseers of the world. He foresaw in the national parks a new and great national economic asset. The educational and other propaganda by which this movement was presented to the people, which the writer had the honor to plan and execute, won rapidly the wide support of the public. To me the national parks appealed powerfully as the potential museums and classrooms for the popular study of the natural forces which made, and still are making, America, and of American fauna and flora. Here were set forth, in fascinating picture and lines so plain that none could fail to read and understand, the essentials of sciences whose real charm our rapid educational methods impart to few. This book is the logical outgrowth of a close study of the national parks, beginning with the inception of the new movement, from this point of view. How free from the partisan considerations common in governmental organization was the birth of the movement is shown by an incident of Mr. Mather's inauguration into his assistant secretaryship. Secretary Lane had seen him at his desk and had started back to his own room. But he returned, looked in at the door, and asked: [Illustration: _Copyright by Haynes, St. Paul_ THE GIANT GEYSER--GREATEST IN THE WORLD Yellowstone National Park] "Oh, by the way, Steve, what are your politics?"