Double Sided 19th C. Mensuration Notebook Page with Watercolor Diagrams in Period Frame biblical In great condition

In great condition

On the back side of the rack is a small area of residue I'd guess from the surface of a wall

to the black painted details and string rein pulled taut on either side

and  with what I believe is its original

and as saturated as if it were painted yesterday

Double Sided 19th C. Mensuration Notebook Page with Watercolor Diagrams in Period Frame biblical In great conditionI just can't resist a pretty diagram, all the more so in watercolor on the page of an earlyish 19th century mensuration notebook, and even better in a terrific period frame holding two pieces of glass, so as to make the flip side with more diagrams visible on reverse. Lovely just to look at, but also nice to be reminded of how to calculate the area of a square, draw an angle from a quadrilateral, etc! Framed as found: 10 1 8" x 8 11 16 x 3 4. Paper: 6