Crystals - Alan Holden 1958

Alan Holden from the Bell Laboratories explains how crystals are formed and why they are shaped the way they are.

Alan Holden (1904-1985) was a physicist who helped to develop sonar equipment used to detect submarines during World War II. Born in New York City, he went to work for the Bell Laboratories Division of the American Telephone and Telegraph Corporation in N.J., after receiving his bachelor's degree from Harvard in physics and mathematics in 1925. Later, in 1935, he joined the research staff where he worked as a physicist until retiring in 1960.

During World War II, he helped to develop methods for producing the large crystals that form the heart of the sonar equipment used by the United States Navy to locate enemy submarines. 

The Physical Science Study Committee (PSSC), made up of a group of MIT scientists, created a series of films in the late 1950s and early 1960s aimed at teaching the physical sciences.

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