Abstract
A recent discovery of American clinical medicine has made necessary an increased understanding of a subject which was very much alive in German and other European scientific circles from the turn of the century until the impact of World War II suppressed its light. | The recent discovery is that tetracycline appears to have a preferential localization at tumor sites. Tetracycline's fluorescence upon irradiation with ultraviolet light increases the usefulness of this discovery. But tetracycline's fluorescence has taken many American investigators into the general subject of ultraviolet light, fluorescent dyes, and interpretation, whose vastness is exceeded only by the inaccessibility of much of the basic work which has been printed in German journals and is not generally, if at all, available in this country. | Fluorescence is a physical phenomenon whose manifestations can be found in the mineral, petroleum, food, drug and many other industries. Criminology, agriculture, bacteriology, botany, medical and biological science, are only part of the vast spectrum of studies in which fluorescence has been useful.