Historical information

Calipers like these were commonly used in the 19th and early 20th centuries for precision measuring tasks, particularly in blacksmithing, metalworking, and carpentry. Their adjustable design allowed craftsmen to accurately check external dimensions of objects such as wheels, barrels, or machined parts.
These outside callipers would have been especially useful for ensuring uniformity in metal or wooden components, a crucial aspect of engineering, manufacturing, and blacksmithing practices before the widespread use of digital measuring tools.

Physical description

The item is a pair of large iron dividers or outside callipers, used for measuring external dimensions or transferring measurements in metalworking, woodworking, or blacksmithing. The tool consists of:
Two curved arms forming a symmetrical, oval-like shape when opened.
A pivot joint at the top, allowing the arms to move freely for adjusting the measurement range.
A flat adjustment screw mechanism, which helps in finely tuning and locking the calipers in place.
The metal surface is darkened and rusted, indicating significant age and long-term use.