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.
Manifest Destiny meant that westward expansion was America's destiny. The land that was added to the U.S. after 1840 (the start of Manifest Destiny) includes The Texas Annexation (1845), The Oregon Country (1846), The Mexican Cession (1848), The Gadsden Purchase (1853), Alaska (1867), and Hawaii (1898).