This is the Best One of These Things We've Ever Seen

This is from the Istanbul Museum of Cool Old Ottoman Stuff. (Museum's actual name may have been somewhat more formal, but we forget what it was - ed.) It is maybe a foot across. It contains a tiny map of the Eastern Hemisphere (while your correspondent doesn't recall the date of its creation, I do recall that at that time the Eastern Hemisphere was the Whole Known World), with a small little metal thing pivoting around Mecca, and somehow pointing to some impossibly tiny Arabic script in columns below (or perhaps in Turkish script before they changed to the latin alphabet). But why? We don't know. Perhaps one of our dear Turkish friends, who are surely experts on all the items in the Museum of Cool Old Ottoman Stuff, will stop by to enlighten us.