Final answer:
The Arthur and Needham Expedition was a historical event in the 19th century led by Clarence King and James Gardiner Needham. Its purpose was to explore and map the geology and geography of the American West. The results of the expedition were crucial in advancing our knowledge of the region's natural resources and geological formations.
Step-by-step explanation:
The Arthur and Needham Expedition refers to an important historical event that took place in the 19th century. It was a scientific expedition led by Clarence King and James Gardiner Needham of the United States Geological Survey. The primary goal of the expedition was to explore and map the geology and geography of the uncharted territories of the American West. The results of this expedition significantly contributed to our understanding of the region's natural resources and geological formations.