What is this cast-iron device in Moulton Hall's kitchen?

It's way up high in the kitchen, from the days of wood and coal. It could be cranked from below, and would cause the horizontal bar to rotate. The text on the iron box that holds the gears in place says "James Tuck" and then some illegible words.

Was this to open a roof vent?

Thoughts?

Feel free to boost.

#IndustrialRevolution #CastIron #kitchen #MoultonHall