One thing I find interesting is the creators assumed the celestial bodies orbited the earth yet they listed those bodies in the correct order of distance from the sun on the device.
... for an earth-based observer using a mechanical calculator (i.e. algebraically without access to calculus), the Ptolemaic epicyclic method is the most expedient
... we only assume they thought the planets revolved around the earth and not the sun, but for earth-based observers wishing to plot the postions of the planets in the night sky the planets maybe orbiting the sun but their positional escription is revolving about the observer
... they may have been fully aware the planets orbited the sun but for their purposes of description that would have been immaterial