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Hehr-o-graph - Navy Portable Perspective Sketcher

Guest _TZ_
Guest _TZ_
in MISC MILITARIA

Featured Replies

#1

Hi. Thanks for looking. I have this mapping tool that I am looking for more information on. It is marked:

 

Special Devices Division - USN Bureau of Aeronautics

 

Device Number 16-C-12

Serial Number 99

 

Perspective Sketcher Mod II

Contract No. NOa(s)-2174

Mfrd. by Thwing-Albert Instrument Co. Philadelphia, Pa.

 

 

The only thing I can find on google about it is patent information. It seems to be from the 1940's. I was hoping maybe someone would know something about how it was used, how long it was in use.

 

The case measures 37 1/2 inches at its longest, and 22 inches tall.

 

psk.jpg

psk2.jpg

psk3.jpg

psk4.jpg

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