The 100th Meridian, Where East Meets West

The 100th Meridian, Where East Meets West. .

"Experience teaches that it is not wise to depend upon rainfall where the amount is less than 20 inches annually. The isohyetal or mean rainfall line of 20 inches…in a general way…may be represented by the 100th meridian. [In this region] agriculturalists will early resort to irrigation." , - John Wesley Powell, 1879

, Dodge City lies on the 100th Meridian, the 100th longitudinal line west of Greenwich, England. The meridian passes through the city approximately one mile east of this marker between Avenues L and M., The 100th Meridian is historically significant to this region. Much of the land west of the Mississippi River to the Rocky Mountains region was once claimed by France. In 1803 President Thomas Jefferson acquired this territory in what became known as the Louisiana Purchase. The approximately 827,000 square mile territory was purchased for $15 million and doubled the size of the country., The land on which Dodge City sets was included in the Louisiana Territory. However the western and southern boundaries of the purchase were poorly defined due to competing claims by Spain., In 1819, the border between the Louisiana Territory and the Spanish claims was defined by the Adams-Onis Treaty. In this treaty, the intersection of the 100th Meridian with the Arkansas River (located approximately one half mile south) was fixed as one corner. The land on which you stand remained part of the Louisiana Territory under the jurisdiction of the United States. The land to the west and south of the river remained for a time under the control of Spain's Mexican colony., After the United States acquired the area south of the Arkansas River from Mexico, the 100th Meridian was used as the western boundary of the Osage Indian Reservation. When the United States government established Fort Dodge for its strategic location on the Santa Fe Trail, the site selected was to the east and within miles of the 100th meridian. In 1872, the town of Dodge City was established on the west edge of the military reservation, leaving the present day city astride the 100th Meridian., The 100th Meridian, although an imaginary line on the surface of the earth, has long symbolized the end of the east and the beginning of the west., Major John Wesley Powell, an early western explorer and the second director of the United States Geological Survey, recognized the 100th Meridian as the natural demarcation line between the humid east and the arid west., The 100th Meridian approximates the 2,000 foot elevation line above sea level. Weather systems divert moisture from the Gulf of Mexico easterly from this point. To the west the climate becomes more arid and the land slopes gently upwards to the Rocky Mountains., Text resource: Geography at About - http://geography.about.com. Photo credits: John Wesley Powell courtesy Utah State Historical Society; Fort Dodge, courtesy Kansas Heritage Center; Thomas Jefferson, painting by Rembrandt Peale, White House Collection; Map of Louisiana Purchase and land acquisitions, designed by Cynthia Vierthaler, Spearville News, Inc.