HANS ERNST Eightieth Birthday Commemoration HANS ERNST celebrated his 80th birthday on 22 October 1972. He was born in Australia, where he won a scholarship in a state-wide competition to Melbourne Technical College. Here he graduated in Mechanical and Electrical Engineering in 1911. After 4 yr of Engineering Practice in his homeland he moved to the USA, and having served in the Royal Air Force, Canada, during the First World War, joined The Cincinnati Milling Machine Company in 1926 (now Cincinnati Milacron Inc.) as Director of Research. He held this position until 1957 when he was appointed Herman Schneider Professor of Research at the University of Cincinnati. Here, he created, conducted and inspired highly valuable research projects with the University's rapidly expanding graduate co-operative program. After retirement from the University he carried his research activities, as a visiting professor, to the Technical University Technion in Haifa, Israel. During his retirement in Clearwater, Florida, he is active in Astronomy, writes a monthly newspaper column on the subject, and has organized a society of amateur star gazers. He and his wife, Adele, celebrated their Golden Wedding Anniversary on 23 August 1972. His life's accomplishment is metal cutting and machine tool research and development within "the Mill". He has clarified the fundamental relations of forces, stresses, and strains in chip formation and particularly the significance of friction in this process. His findings found numerous technical and commercial applications within the activities of his company, and have been formulated into the Ernst-Merchant Theory which, for about 25 yr has been one of the corner-stones of metal cutting research all over the world. E. K. HENRIKSEN