THE WEST AT THE OPENING OF THE CENTURY 162 GROUP II.—BIRTH OF THE AMERICAN IDEA. I. America for Americans. ACQUISITION OF LOUISIANA 171 A GLANCE AT OUR PURCHASE 175 II. The Pathfinders. LEWIS AND CLARKE ASCEND THE MISSOURI 184 THEY CROSS THE CONTINENT 191 PIKE EXPLORES THE ARKANSAS VALLEY 198 NEW MEXICO IN 1807 205 GOLD IN COLORADO.—A TRAPPER'S STORY 208 THE FLAG IN OREGON 211 LOUISIANA ADMITTED 1812 214 III. The Oregon Trail. THE TRAPPER, BACKWOODSMAN, AND EMIGRANT 215 LONG EXPLORES THE PLATTE VALLEY 219 MISSOURI AND THE COMPROMISE OF 1821 223 ARKANSAS ADMITTED 1836 227 THOMAS H. BENTON'S IDEA 227 WITH THE VANGUARD TO OREGON 233 TEXAS ADMITTED 241 _Interlude._ NEW POLITICAL IDEAS 246 IOWA ADMITTED 248 THE WAR WITH MEXICO 248 CONQUEST OF NEW MEXICO 251 TAKING OF CALIFORNIA 256 THE MORMONS IN UTAH 264 GROUP III.—GOLD IN CALIFORNIA, AND WHAT IT LED TO. I. The Great Emigration. EL DORADO FOUND AT LAST 271 SWARMING THROUGH THE GOLDEN GATE 276 THE CALIFORNIA PIONEERS 279 CALIFORNIA A FREE STATE 285 ARIZONA 288 II. The Contest for Free Soil. THE KANSAS-NEBRASKA STRUGGLE 290 KANSAS THE BATTLE-GROUND 295 THE BATTLE FOUGHT AND WON 299 TWO FREE STATES ADMITTED 307 III. The Crown of the Continent. GOLD IN COLORADO, AND THE RUSH THERE 308 THE PACIFIC RAILROADS 315 KANSAS, NEVADA, NEBRASKA, AND COLORADO ADMITTED 320 THE RECENT STATES 322 THE WORK OF EIGHTY YEARS 326 LIST OF ILLUSTRATIONS. PAGE TAKING POSSESSION FOR FRANCE _Frontispiece_ SPANISH ARMS 1 SHIP OF THE SIXTEENTH CENTURY 2 ISABELLA OF SPAIN 3 MEDAL OF CHARLES V. 5 PONCE DE LEON 6 BALBOA DISCOVERING THE PACIFIC 8 FRENCH MAP OF 1542. FROM JOMARD 10 DE SOTO 11