NATIONAL PHYSICAL LABORATORY (C) CROWN COPYRIGHT / SCIENCE PHOTO LIBRARY NATIONAL PHYSICAL LABORATORY (C) CROWN COPYRIGHT / SCIENCE PHOTO LIBRARY
Vacuum spheres. These spheres are used in conjunction with a hypersonic wind tunnel (not seen). When the wind tunnel is in use, the vacuum in the spheres allows the air to flow through the tunnel at supersonic speeds. Photographed at the National Physical Laboratory, Teddington, UK, in the 1940s.
Model release not required. Property release not required.