Filtering by: Resource Type moving image Remove constraint Resource Type: moving image Subject ellsworth, lincoln, 1880-1951 Remove constraint Subject: ellsworth, lincoln, 1880-1951 Subject discovery and exploration Remove constraint Subject: discovery and exploration Subject icebreakers (ships) Remove constraint Subject: icebreakers (ships) Time Period (Topic) 1930s (1930-1939) Remove constraint Time Period (Topic): 1930s (1930-1939)