This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Aeronautic instrument exhibit of thermometers inclinometers airspeed meters and pressure gages at A.P.S. May . National Institute of Standards and Technology National Institute of Standards and Technology The images in the Aeronautical Instruments Photographic Collection are in the public domain and are not subject to copyright