Achondroplasia is one of the most common types of dwarfism. Learn about its causes, diagnosis, and treatment. Achondroplasia is one of the most common types of dwarfism.
Westward Expansion (1807-1912) The Surge West. Summary. The westward movement of the American population occurred in intermittent flurries of settlement. The first began early in the nation's history, resulting in the statehood of Vermont, Kentucky, Tennessee, and Ohio, all of which were admitted to the Union between 1791 and 1803.
Westward Expansion: The Louisiana Purchase. 1  One of the first colored illustrations to be put into print, John H.B. 2  Thomas Jefferson's purchase of the Louisiana Territory in 1803 â over 600 million acres at less than 4Â¢ an acre â was an economic as well as a political victory, as it avoided a possible war with the French. The Louisiana Purchase demonstrates Jefferson's ability to make pragmatic political decisions.