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.
The California Gold Rush was a major factor in expansion west of the Mississippi. That westward expansion was greatly aided by the completion of the Transcontinental Railroad in 1869, and passage of the Homestead Act in 1862.