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. linear distance measuring devices
9. rulers (measuring devices)
10. [rulers by form]

Anotations

Scope note:

Rules comprised of short strips of wood joined at their ends by rivets so that the pieces are foldable, in a zigzag manner, in parallel planes; most usually the strips are in 6-inch or 1-foot lengths, and the rules are 6 feet or 8 feet long when open; also of similar lengths in metric units. Distinct from "folding rules" which tend to be shorter and have sections that usually pivot or fold in more than one plane.