The history of hydatid disease goes back to ancient times. The Jews were familiar with it in their sacrificial slaughter of animals, and the Talmud makes definite reference to it. Hippocrates (460379 B. C.) wrote of "livers filled with water." References to the disease were made also by Galen (139-200 A. D.) and later by various writers during the Middle Ages, including Rhazes (860-932 A. D.). At first the condition was considered to be due to morbid processes, such as broken-down lymph glands or collections of pus. Later, however, other investigators brought to light information which led to an understanding of the parasitic nature of Taenia echinococcus. Leuchart, in 1867, described his observations made on artificially infected pigs. However, it was the work of the Italian scientist Francisco Redi (1626-1694) that established the animal origin of the cyst. Thomas, an Australian, published a book in the 1880's. Dévé, of Rouen,