Isaac Newton's Opticks, printed in London in 1704, split a beam of white light with a glass prism into seven named bands — red, orange, yellow, green, blue, indigo, violet — and mapped them to the seven intervals of the musical scale. This system reads that experiment as a single engraved plate: a dark sepia-brown chamber, shuttered against stray light, across which a triangular prism throws its ordered spectrum as fine refracted ray lines. Rational color dispersion, drawn with a measured hand.