Ibberson small heliostat / heliograph
Small hand held heliograph
Obtained from the Netherlands
I was given this by a colleque of mine, Wim van Leunen. According to one of my visitors (thank you Richard) it is an emergency dinghy heliograph. According to Wikimedia this type was developed by Ibberson in the 1940s and used by downed pilots. This one is probably a former life boat instrument. Considering its plastic pouch it is probably from somewhat later. It describes Kelvin Hughes as part of S Smith and Sons. Now Kelvin Hughes was fully absorbed between 1947 and 1953 and by 1966 the name had changed to Smith Industries. Which would date this specific heliograph to anywhere between 1953 and 1966 most probably.
The instructions are only half there but the operation is clear. The crosshairs and circles show up on the small hole and pin that is held before the mirror thus directing the signal in the right direction. See Wikipedia for more information.
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heliopstat
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Small hand held heliograph
Obtained from the Netherlands