This is a recording of Prof. Karl Terzaghi's last lecture on Engineering Geology at Harvard University. The recording was provided to Prof. Whittle (from MIT) during his visit in Japan in the early 2000s, by a Japanese colleague, who must have been a student of Prof. Terzaghi during his last year in Harvard. Unfortunately, the student's name is not known. It was sent by Professor Andrew Whittle to Prof. Dimitrios Zekkos (Univ. of Michigan) in 2017 for free dissemination through Geoengineer.org. Prof. Eduardo Kausel (from MIT), and subsequently Geoengineer.org staff helped improve the quality of the recording.