Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Furnishings and Equipment (hierarchy name)
4. Furnishings (hierarchy name)
5. furnishings (works)
6. [furnishings by form or function]
7. lighting devices
8. [lighting devices by form]
9. lighting fixtures
10. [lighting fixtures by location or context]
11. ceiling fixtures (lighting fixtures)
12. slide fixtures

Anotations

Scope note:

Extension gas fixtures, usually for chandeliers, that use water to seal the joints. Various improvements to the fixtures were invented throughout the mid- to late 19th century, attempting to solve the problem of evaporation of the water, which caused gas leaks.