Design for 1/4 of a Ceiling, and Ornamentation of a Section of a Vault

Anonymous, Italian, Piedmontese, 18th century · 1700–1780 · Pen and black ink, brush and gray wash, over leadpoint or graphite, with ruled construction; framing outline at upper, right, and lower borders in brush and black ink; measuring scale on right border in pen and gray ink over graphite or leadpoint

From the collection of The Metropolitan Museum of Art. Free to download, adapt and use — no permission needed.