1. more para of the interior geography of North America were mapped.
2. The Americans "realized" that from the Atlantic ocean to the Pacif Ocean, there was no water passage.
The County unit system. See the link below that will take you to that.
Answer:
Explanation:
Founded on July 16, 1790, Washington, DC is unique among American cities because it was established by the Constitution of the United States to serve as the nation's capital. You can read the actual line at the National Archives. Even before coming of age, DC was nearly completely destroyed.