A theodolite instrument being used for testing wind velocity at different altitudes. The purpose is to accurately calculate the drift of shells fired from rifles. The picture shows a private holding a small rubber balloon that is released and tracked using the theodolite. The officer operating the instrument is 2nd Lt. Ivan R. Tannehill, , and Private Strange holds the telephone receiver and transmitter to relay readings to the meteorological plotting room. Issued notes: 60740C.

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Size: 8493px × 5800px
Photo credit: © piemags/NSC / Alamy / Afripics
License: Licensed
Model Released: No

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