Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Furnishings and Equipment (hierarchy name)
4. Tools and Equipment (hierarchy name)
5. equipment
6. [equipment by process]
7. signaling equipment

Anotations

Scope note:

Signaling apparatuses consisting of an upright post with one or more arms that can be moved in a vertical plane, different positions of the arm or arms representing different letters or messages. Semaphores were often placed on towers in lines across the landscape, sending messages for distances prior to the invention of the telegraph.