Small spring vice
1 Small spring vice, with ring on
This calliper was used to measure external dimensions and the diameter of parts or objects.
James Watt was an inventor, mathematical-instrument maker and engineer. He had a workshop in Glasgow at the University where he made and sold mathematical-instruments such as quadrants, compasses and scales. Watt is best known for inventing a separate steam condensor for the Newcomen steam engine, improving its efficiency and making it cheaper to run.