A chain of mountains extends along the entire western part of the hemisphere.
Pampas is taken from an Indian word meaning plain .
It drains an area almost equal to the size of the United States. It is navigable for 2,300 miles from the sea. The average rainfall in the Amazon Rain Forest is 100 to 120 inches a year. In North America the mountains are called the Rocky Mountains and in South America they are called the Andes Mountains. In Mexico they are known as the Sierra Madre.