Protractor Variation I is a painting by contemporary artist, Frank Stella, made in 1969. This large painting is in the shape of a large semi-circle. The unconventional canvas measures sixteen feet across its entire width. By comparison, this painting is wider than the combined height of three average adults. The height of the arched canvas is eight feet, and the full length of the curved arch is twenty-five feet. This painting is an example of Stella’s innovative experiments with shaped canvases. in this case, the shape of a semi-circle, and titled after the common mathematical tool, the protractor. As one stands in front of this large, colorful painting, one notices seven distinct shapes, some overlap and others are placed side by side. Most prominent is a purple band, at least a foot and a half thick that traces the entire arc, as well as the bottom center of the straight edge, which is parallel to the floor. Inside this purple border is a bright coral pink band that hugs the edges of the purple band, and the general curve of the arc and straight edge. From the center of the bottom edge is a yellow-ochre stripe that bends slightly to the right as it reaches the top of the painting but stops at the coral-pink stripe. Left of the yellow ochre is a fan-like shape, the color is a very deep purple, almost black; the color of eggplant. In the right side of the painting is a small yellow triangle nestled in between the peach-orange stripe to its right and a small, light blue curved stripe on its upper left next to a larger dark orange stripe. The Protractor series which he worked on from 1967–1971 was inspired by the circular-plan towns that Stella encountered during his travels in Western Asia, particularly the arches and decorative patterns he admired in Iranian art and architecture. He introduced the arcs and curves that can be created with a protractor, but also the straight edges as well. In his paintings the straight lines provide a framework or stabilizing structure for the curves.