The corpulence of the body of medical knowledge is well reflected in the corpulence of our textbooks. Since their first editions in 1892, 1927, and 1942, Osler's (now Harvey's) The Principles and Practice of Medicine, Cecil's Texbook of Medicine, and Wintrobe's Clinical Hematology have grown 50%, 100%, and 250%, respectively, with pages now numbering in the thousands.
In earlier years, such works did indeed serve as textbooks, and students could read several in their entirety during their medical school years. In our time, however, textbooks have attained encyclopedic dimensions and serve primarily as reference sources. No medical student does or is expected to read cover to cover the textbooks for subjects in their curriculum.
In response a new genre has arisen: introductory volumes of manageable size, intended to bring the reader the essentials of a particular subject. In fact, they often carry in their titles such designations as "fundamental," "essential,"