1948. An unusual, possibly unique item. This is a report done by Dr. Wilhelm Geyger as a scientific consultant in the US Military Government, Berlin Sector, Germany in June 1948. It consists of blueprint style copies of a typed manuscript on magnetic amplifiers, including research work done by the author. I can't find evidence in OCLC that this was ever published. There is a sticker on the first page indicating it was the property of R. L. Briggs. Approximately 70 pages, most typed with a large section in the rear with circuit diagrams, bibliography, etc. Good. Binder.