In his book 'Writings 1973–1983 on Works 1969–1979,' Michael Asher recalls: 

"My proposal for this space was to cut an architectural reveal, 1⁄4 inch wide and 1 1⁄2 inches deep, into the wall at floor level, around the perimeter of the room. The architectural reveal began and ended at the entry/exit passageway, without turning into the passageway, since that functioned as a transition zone between two exhibition spaces. Because the reveal followed the perimeter continuously, it was necessary to cut around and into the vertical projections and the recess. A masonry grinder was used to cut into the wall, making a recess averaging 1 1⁄2 inches deep, so that the floor line became indistinguishable.

"The creation of a pictorial or sculptural sign traditionally involves the addition of materials to an initial support until some sort of resolution is brought about. The work at the Lisson Gallery reversed this process by creating a mark or sign through a process of material subtraction, in which existing materials were withdrawn from the architectural support. This procedure of material withdrawal was similar to that used by Lawrence Weiner in several works he did in 1968 in which he removed materials from gallery floors and walls."