Photograph of August Krogh, who showed that blood capacity for oxygen is influenced by carbon dioxide tension. Krogh was awarded the Nobel Prize in Physiology and Medicine in 1920.
Portrait of Harvey Williams Cushing in right profile, looking downward. Cushing is credited with developing neurosurgery, and was a pioneer in studying the pituitary and the hypothalamus.
Portrait of Claude Bernard. Bernard studied many different aspects of medicine, and emphasized the interrelatedness of life functions and the importance of the body's preservation of internal stability.