Vintage Original Blueprint C. 1950 - Not a reproduction!

Description

Here is a vintage original blueprint (or plan) created by Engineering for Production to be able to build the item depicted.
In our case a ship.
Ever wondered why blueprints were blue and not black or red or any other color than blue, well, it's because the technique in making blueprints caused the paper to turn blue. ... (also known as Prussian Blue), except where the blueprinting paper was covered, and the light blocked, by the lines of the original drawing.
dimensions: 36.5x18.5 inch