The 14th edition of the Encyclopedia Britannica (1929) notes that Louis Agassiz was a Swiss-American naturalist and geologist whose catalog (of all the names applied to all the genera of animals) had a practical value that can hardly be overestimated. His study of glaciers was the most important of all his works, which included Lake Superior (1850) and Contribution to the Natural History of the United States. As a professor of zoology at Harvard, he was the ablest scientist America had known. He said, “The book of nature is always open. Strive to interpret what really exists.” His attitude toward Darwinism all his lifetime was cold and unsympathetic.