Extensions of Nursing Field 189 women, and are also responsible for the manage- ment of the nursing department in the hospital. Practically all of these schools have one or more assistant superintendents — night superintendent, and day assistants, as well as a fairly Assistants large staii of graduate nurses in charge of departments as head nurses or supervisors. The duties of all these workers is two-fold — executive and instructive. The extension of classroom teaching, and es- pecially the introduction of preparatory courses, made it necessary to assign certain Instructors staff nurses exclusively to teaching work. At first this was largely the teaching of practical nursing. Later the nurse-instructor took over the teaching of elementary sciences and some other subjects. Many large schools now have two or more full-time instructors. In other instances visiting instructors, who live at home and divide their time between several neighbouring hospitals, are employed. A few hospitals are now appointing educational directors, who not only teach but are responsible for organizing and directing all teaching work. Many nurses specialize in various forms of thera- peutics, X-ray and electrical treatment, hydro- therapy, massage, etc. Others assist in bacterio-
