The art is done by a W.H. Miller… no clue who he is, but he is a pretty amazing penman and engrosser. Click on the image to see a higher resolution. If you have any information on this guy, please let me know!
Viewing it up close is pretty amazing, he has taken a lot of care and time to work on this. The ink is probably iron gall ink, but on some parts it has turned a little brown. How interesting!