Chemical engineering emerged upon the development of unit operations, a fundamental concept of the discipline. Most authors agree that Davis invented unit operations if not substantially developed it. He gave a series of lectures on unit operations at the Manchester Technical School (University of Manchester today) in 1887, considered to be one of the earliest such about chemical engineering. Three years before Davis’ lectures, Henry Edward Armstrong taught a degree course in chemical engineering at the City and Guilds of London Institute. Armstrong’s course ‘;failed simply because its graduates … were not especially attractive to employers.’ Employers of the time would have rather hired chemists and mechanical engineers. Starting from 1888, Lewis M. Norton taught at MIT the first chemical engineering course in the United States. Norton’s course was contemporaneous and essentially similar with Armstrong’s course. Both courses, however, simply merged chemistry and engineering subjects. This book represents an essential source of up-to-date practical information on this subject.