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. power producing equipment
8. engines (power producing equipment)

Anotations

Scope note:

Engines that are activated through the use of animal locomotion. The animal works either in a vertical or horizontal plane to drive a central axis, treadwheel, or series of gears in more sophisticated machines.