heligraphs
A shame; I recently sent my extra heliographs to a militaria auction. The common configuration has just a single mirror but the duplex mirror system shown in one of your photos is the nicest set-up. There is also an electric lamp, battery powered; the one I have is labelled: Lamp Electric Signalling Daylight Mark II-1918. I've seen tripods made in Toronto with WW2 dates. Others I've seen have WW1 dates. Somewhere I have a books of communications devices that includes a full description of the heliographs - can't put my finger on it right now but will keep looking.
The photos show a particularly nice example - in particular the nice condition of the duplex mirror case and contents. ............. Brian
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