It's the pages headed with "Single Fellow"s and Double Fellowship" that really sold me on this one, a math notebook dating to 1820 kept by an Isaac Ilsley of Portland, Maine. And really I might be tempted to extract the former from the notebook to frame it--to admire the mast head-like "Single Fellows" so beautifully lettered, and also as it delivers a definition of fellowship that resonates far beyond its context: "Fellowship is when two or more join their stock and trade together..." Altogether a nice, clean, clearly inked example of one of these early math notebooks, with pretty headers and assorted flourishes throughout.
7 5/8 x 6 3/8; 14 pp filled front and back. Photos provide a representative but not complete sample of pages.