This is an old world device that is currently disguised as a fireplace in the New York Yacht Club. The painting obscures quite possibly the viewing area where a projection of an image would have been emitted for the user(s).
The opening beneath, appropriated naturally by Masons in the historical fabrications, appears to be the mouth of the chimney... however, note that this is entirely without any way for the smoke to exit! This pattern is perfectly replicated in some historic buildings related to the US founders -- who also owned grand fireplaces that didn't actually have a smoke-exit!
The opening, according to our estimation, would be the Output of the device - like a 3D printer outputs a result from the user's inputs. Being that it was a verbal computer that spoke, it would display concepts probably holographically and the empty opening produced designs, materials, papers, etc as the user desires.
... Are, are we living in the dark ages?
The past has a wonderful way of showing us advanced mathematical fractals in architecture only explainable by the user of advanced computer systems able to chart such things rapidly at scale. Additionally, street planning in the 1500s with sticks and string would not have been sufficient and only scanning equipment could produce meticulous data needed to layout entire cities perfectly level spanning 100+ miles in every direction.
For the curious:
