bild
EARLY 20TH CENTURY MILITARY AMPLIFIERS
Early 20th Century military amplifiers. Historical image of large amplifiers being used to listen for approaching enemy aircraft. Photographed at the US Air Force base in Bolling Field, Washington DC, USA. Published in 1921. (KEYSTONE/SCIENCE PHOTO LIBRARY/LIBRARY OF CONGRESS/SCIENCE PHOTO LIBRARY)
Instruktionen
COPYRIGHTPFLICHTIG
Lizenz
Rights Managed
Erstellungsdatum
20110412
Ort
Credit
KEYSTONE
Source
SCIENCE PHOTO LIBRARY SPL
Byline
LIBRARY OF CONGRESS
Grösse
4724 x 3798 px
Dateityp
JPEG