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.
Expansion in the North West. The United States added additional areas as the four newest states, North Dakota, South Dakota, Washington and Montana, after passing the Enabling Act. Statehood for Arizona. Arizona was finally admitted as the 48th state, marking the completion of the contiguous 48 states.