At the root of every Wall drawing by the artist lies a precisely formulated assignment, or concise work description. This contains all the painting instructions which his assistants – often artists – have to follow as precisely as possible. In the execution, LeWitt's strict concepts appear infinitely more inviting than one would expect from the original underlying principle. This is also the case with 'Wall drawing # 801: Spiral', which was executed for the first time in the Cupola of the museum in 1996. The essentially simple principle of a slightly sloping white line spanning the whole Cupola produces an overwhelming result in practice.