A complex instrument panel in the Control Room reflects these intricate operations. The first section of the panel is used only for air bursts, receiving signals from the bomber indicating re- lease and, seconds later, recording the detonation. The second and third sections contain the frequency control equipment for the motor-generator set which supplies power to the timing equipment, with voltage recorders, connected to various points in the target area -~ thus assuring accurate timing -- and records for wind velocity and direction. In order to activate test equipment at the exact time, very precise control of the frequency for the timer is required, New Instrumentation Several instruments of new or improved types have been developed by Edgerton, Germeshausen & Grier, Inc., a prime contractor to the Atomic Energy Commission, for recording and measuring effects of the detonations during the 1957 series. Measurement of events that take place within ten billionths of a second now are possible, . One new instrument that measures within such a time range is an electronic "streak" camera that was given a trie] in the 1956 Paci« fic test series and is being used by EG& to register effects in this year's Nevada nuclear tests, In the camera, the light image is received by an electronic device that translates it into intensified electrical impulses that are beamed to a phosphorescent screen in the back of the camera and then recorded on a stationary film. Each individual image is recorded in a different position on the film by means of a scanning device so the film has a "streak" of consecutive pictures on it, explaining the descriptive name of the camera, The extremely brief duration of the event pictured is made possible by the speed of the scanning mechanism. In another development, EG&G is attempting, with newly developed equipment, to photograph shock waves as they are reflected from objects and from people. Comparatively weak shock waves are photographed as they are reflected from persons at a safe distance from the detonation, as a study into the effects of blast on human bodies, wt : The reflected shock waves cause visible distortions of light similar to those created by a mirage of hot air, and special techniques have been worked out for obtaining photographs of the reflected waves, The same principle is applied in photographing shock waves of materials and designs for shielding instruments, such as cameras, from the blast of nuclear detonations. Information on the way shock . tbibcg ae a oe