A skylid, a louvered skylight that opens and closes automatically, and requires no external power , 04/1974

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Size: 1164px × 1718px
Photo credit: © PF-(usna) / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: .., agency, archives, boyd, boydnorton, documerica, environmental, environmentalprotectionagency, historic, history, nara:arcid=555303, national, norton, protection, usa, usnationalarchives