Volumes VIII and IX of this encyclopedia cover medical subjects alphabetically from disorders of the larynx to potassium. The articles represent the work of many leading contributors to medical periodical literature. There is occasionally unevenness in the presentation, but on the whole the material is sound and adequate. There are some fine articles by Chevalier Jackson dealing with the lungs, by Cheney on the gallbladder, and by Boothby, Heiser, Mann and many other distinguished workers in the medical field. The editors have chosen extraordinarily well in their contributors, and the books may be generally recommended as competent and authoritative.