National Geographic : 1943 Jun
The Making of Military Maps 767 From a Japanese Map She Culls Details for a U.S. Bomb-target Chart This Army Map Service cartographer is locating factories, docks, railroads, and other man-made works on a chart of a Nipponese city. They will be entered on the Army chart in the making, beneath her right arm. On a Basic Blue Map She Drafts Shore Lines, Lakes, and Streams Free-hand tracing in black ink will include all the hydrographic features of the area. When the map is rephotographed, the original blue lines will be filtered out, leaving the black tracing to be photographed and etched into a color plate.