Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Furnishings and Equipment (hierarchy name)
4. Measuring Devices (hierarchy name)
5. measuring devices (instruments)
6. [measuring devices for extent]
7. distance measuring devices
8. size measuring devices

Anotations

Scope note:

Small, movable, graduated scales running parallel to the fixed graduated scales of precision instruments, such as sextants or transits, and designed to measure a fractional part of the smallest divisions on the fixed scales.