Contralto Marian Anderson sang at the steps of the Lincoln Memorial, April 9, 1939, to an estimated crowd of 75,000 people. University of Pennsylvania hide caption

itoggle caption University of Pennsylvania

The Victor Orchestra crowds around an enormous horn for an early acoustical recording session. courtesy of Recorded Sound Section, MBRS Division, Library of Congress hide caption

itoggle caption courtesy of Recorded Sound Section, MBRS Division, Library of Congress