Looks like a crane for hauling things up the stairwell.

Hmm…but why not just use the elevators?

If it is 10 feet tall it won’t fit in the elevator.

True! What’s that bag that says Yale on it?

May hold the chain.

Yale is the brand of the lift.

@Tropical_Willie That’s what it looks like to me.

But why not use the elevators? to repeat @dxs‘s question. Maybe they needed to do the work immediately, and the elevator was out of order and would stay out of order for a while?

@flo To repeat @Tropical_Willie‘s sensible answer, because “if it is 10 feet tall it won’t fit in the elevator.” It was in a library. I’m thinking maybe they used it for book racks or something. The open area between the stairs is huge—about 36ft^2 (6’ sides), so it could definitely fit decent-sized stuff.

Looks to me like that part that says Yale is the motor and the boxy can thing next to it would hold the chain when hauled in.
Possibly that was only used during construction, or maybe only after construction to haul fixtures and books in once at that time. It might not be practical to bother to remove/re-use it.
They might use that instead of elevators for stuff that might damage the elevators, i.e. this is in lieu of a freight elevator.
Is that building in a flood zone? Totally speculating that they might use that for some emergency hauling of big stuff to upper floors.

@dabbler Your analysis makes a lot of sense! The building is right by the water, so I’d think it’d be in a flood zone. In fact, the whole building is elevated fromt the ground at least 20 feet. It also seems to be very disaster-proof. There are many evacuation roots, fire doors, areas of refuge, and the building is mostly concrete.

How did I miss @Tropical_Willie‘s answer? That makes sense.