The Works of Charles Darwin: v. 9: Geological Observations on South America (1846) (with the Critical Introduction by J.W. Judd, 1890)

The ninth volume in a 29-volume set which contain all Charles Darwin's published works.

Darwin was one of the most influential figures of the 19th century.

His work remains a central subject of study in the history of ideas, the history of science, zoology, botany, geology and evolution.