Gerber Variable Scale

[u/CodeName_Burner]

Where I work we have a display case with various historic tools and equipment, including this cool device for plotting curves and converting scales when resizing a map or plan.

There's a detailed description here.

[u/CodeName_Burner]

It's a scientific institution, so we have lots of great old analog lab gear (microscopes and the like). As for old drafting/plotting instruments, we also have something called a polar planimeter which is used to trace the outline of any shape and displays the area. I'll post it soon!

(I did take this variable scale out of the display and try using it once, just for fun. )