Mechanical Dashed Line Instrument (30792308421)
Summary
The three notched discs and a drafting pen mounted on the spring-loaded base created different dash-line patterns for boundary, road, river, and other linear map symbols.
Tags
cia
central intelligence agency
map drawing instruments
intelligence
maps
ultra high resolution
high resolution
technical drawing
Date
09/11/2016
Source
Mechanical Dashed Line Instrument
Link
Copyright info
Public Domain