An interesting little engineering device
by Xeni Jardin from on (#532ZK)
Apparently this thing is called a Roebling device, and is used to calculate wire resistance per foot based on wire diameter.
A very interesting little engineering device, for a highly specialized use.
Just looks really cool, too.
From IMGURian @silvercatbob.
Roebling device used to calculate wire resistance per foot based on wire diameter