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1800-1860: Science and Medicine: Chronology

1800-1860: Science and Medicine: Chronology




  • A smallpox pandemic begins to ravage Indian peoples in Central and Northwestern regions, particularly along the Missouri River.





  • Cartographer John Cary publishes a map of the Pacific coastline.
  • 15 July Zebulon Pike starts an exploratory expedition west of the Mississippi River into northern New Spain and eventually crosses the Great Plains.
  • 23 Sept. Lewis and Clark return to St. Louis after exploring the Upper Missouri River and the northwestern region of the present-day United States.


  • The North West Company explorers spend the next four years on the Upper Columbia River searching for a route to the Pacific.
  • John Colter journeys through the Bighorn Basin into present-day Yellowstone National Park.
  • Mar. Manuel Lisas fur-trading party begins to explore tributaries of the Upper Missouri River.


  • A second American overland expedition, financed by John Jacob Astor, travels through the Northwest and reaches the Pacific Ocean by April 1813.


  • The journals of Lewis and Clarks expedition are published.



  • Henry Schoolcrafts party locates the source of the Mississippi River.


  • Over the course of the next six years the Hudsons Bay Company explorers travel through present-day Montana, Idaho, Oregon, Utah, and California.
  • A party of trappers employed by the Rocky Mountain Fur Company, among them James Bridger, become the first Euro-Americans to reach the Great Salt Lake.


  • Henry Schoolcrafts map of the Upper Mississippi River is published.
  • Albert Gallatin publishes A Table of Indian Languages of the United States.


  • Henry Schoolcraft leads a second expedition to the mouth of the Mississippi River.



  • Albert Gallatin compiles a map of the Great Basin and the Colorado River.
  • A smallpox epidemic begins to sweep the Northern Plains tribes and by 1840 kills thousands of Blackfeet, Pawnees, Mandans, and others.


  • A map drawn by Benjamin Louis Eulalie de Bonneville depicts the major river systems west of the Rocky Mountains.


  • The U.S. Army Corps of Topographical Engineers begins to conduct the first geological explorations of the Trans-Mississippi West.


  • Albert Gallatin and others begin the American Ethnological Society.


  • Apr.-Aug. John James Audubon travels to the mouth of the Yellowstone River, examining natural flora and fauna along the way.
  • 16 June John C. Fremont leads an expedition from Independence, Missouri, along the Kansas River, over the Rocky Mountains, and eventually to the Columbia River and California.


  • John C. Fremonts account of his expedition to the Rockies, Oregon, and California is published.


  • Henry Schoolcraft receives a government commission to assemble information on history and culture of North American Indians.


  • Native American and Anglo travelers along the overland trails suffer from cholera epidemics.
  • July The U.S. Topographical Corps begins its survey of the Rio Grande.



  • Audubon begins publishing The Vivaparous Quadrupeds of North America.


  • The Pacific Railroad and the U.S. Army Corps of Topographical Engineers conduct a series of expeditionary surveys in the Northwest until 1855.


  • G. K. Warren compiles all known geographic information into a map of the United States from the Mississippi River to the Pacific Ocean.
  • June-Dec. John Boardman Trasks geological report on the agricultural and mineral resources of the coastal mountains is presented to the state legislature of California.

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