Books on Diseases examine physiological conditions that negatively impact the functioning of a human metabolism. Diseases can be identified through common associated symptoms, or may require more complex medical examination. Titles dealing with disease include: A Treatise on the Diseases of the Tongue, Diseases of the Ear, Diseases of the Liver, Pancreas and Ductless Glands, Dyspepsia and Its Kindred Diseases, Health and disease, A history of the chronic degenerative diseases of the central nervous system, A Guide to the Treatment of Diseases of the Skin, Lectures on Bright's Disease of the Kidneys, Lectures on Tropical Diseases, Syphilis and Other Venereal Diseases, Yellow Fever, a Nautical Disease, and Skin Diseases of Parasitic Origin.