This is one of three double-sided pages from an early 19th c. Newburyport, MA  school notebook I'm listing--clearly the work of one person--which came from the collection of longtime New England collectors Bev and John Titus. I love early watercolored lettering and diagrams just about as much as anything in the world (and have also been kind of obsessed with sun dials lately) so just swooned when I saw these.  The side headed "Of Upright Planes" shows "how to drawn the [?] lines  [on a sundial I believe] on a direct North Plane in the latitude of Newburyport," while the reverse seems to show the "East Direct Dial in the latitude of Newbury."  (Newburyport incorporated as a separate township from Newbury, MA in 1764.) For me, these geometries rendered in rich watercolors in the best palette and precisely detailed in ink combined with beautifully lettering above just totally do it for me. Knowing they were done just a few miles from me, some 200 years ago, is pretty nice too. 

Framed as found: 16 1/2 x 11 1/2 x ; sight: 12 1/2 x 7 1/2. The frames appear to have been custom made for these, not very long ago. The page is pretty much hermetically sealed inside the frame, between two panes of glass, with wooden plugs/pegs near the corners on the top edge of the frame. It appears to me one would need to drill down through those plugs in order to disassemble the frame should one wish to reframe them--certainly doable but just a note that frames don't readily pull apart.