First page of a 15th-century guidebook on constructing volvelles, and some Early Modern ones, reproduced here with the kind permission of The Bodleian Libraries, The University of Oxford.
You may click on any one of the images to view a slideshow with further information, including the manuscript and folio numbers. As these are simple snapshots I took of the manuscripts, you are encouraged to contact the Imaging Services of the Bodleian Libraries directly to obtain professional reproductions.
Please note that MS Savile 100, f.8r has also been reproduced on the LUNA site of the Bodleian Libraries. See also the late 15th-century brass equatorium and astrolabe at the Museum of the History of Science at Oxford (inventory #49847).