Before a stained glass window is made a small, a scaled design is produced to show the client. This initial drawing is known as a “vidimus”. From this a full size cartoon is produced which contains all the information the glazier would need to make the window. In the Middle Ages stained glass designs were normally specific to the location or the ideals of the donor, to illustrate given topics or events, such as is the case with the Boppard panels. The inspiration for stained glass designs came from a wide range of areas, such as Biblical texts, an illustration in a book or manuscript, a painting or some other work of art. Glass painters probably also kept sketchbooks of figures and motifs useful for stained glass, similar to that in the found in the Pepysian Sketchbook, in the Pepysian Library at Magdalene College Cambridge. Over time it also became popular to commission individual artists to create designs for stained glass.
The Burrell Collection has some examples of the preparatory sketches for stained glass such as the one below. It is a 17th century ink design by Jacob Weber (not on display).
A fine silver stained roundel in the collection depicting Adam and Eve shows how designs were copied from other sources, in this case the Nuremberg Chronicles. The Nuremberg Chronicles are an illustrated history of the human world linked in to Biblical stories and theology. It was originally written in Latin around 1493 by Hartmann Schedel, and then translated into German by Georg Alt. It was one of the first books to successfully integrate illustrations with the text, and these were often the inspiration for stained glass panels and tapestries. The Burrell Collection example of Adam and Eve in the “Expulsion from the Garden of Eden” panel is shown below.
Unfortunately the panel has lost a lot of paint, but it is still possible to see how closely it copied the page from the Nuremberg chronicles, below:
Nuremberg Chronicle by Hartmann Schedel. Classmark Inc.0.A.7.2. Reproduced by kind permission of the Syndics of Cambridge University Library.
You can see how they have literally drawn the design directly from the book: