In the hectic days of America's early development, the pursuit of ""impractical"" information such as natural history was held of little importance. The few men who acted upon their ""perennial urge to fill the open niches of knowledge"" in the sciences of ecology and ornithology were not highly regarded by their peers. There was little time and less money to build up herbaria, bird museums, scientific collections and libraries. Yet through the journals of explorers from Columbus onward runs a theme of wonder and joy over beauty and natural resources. Once the idea of the Smithsonian Institution caught hold, other agencies were able to follow the lead. Nomenclature, orderly collecting methods, and popular enthusiasm became established. Mrs. Eifert's capsule biographies of Catesby, Bartram, Lewis & Clark, Alexander Wilson, Robert Ridgway and other leading American ornithologists illuminate the continuity of their work with the modern emphasis on conservation and re-development. She also includes chapters on some scientific explorers of the northern reaches of the continent.