A feather is attached to each finger with a metal ring. The hand becomes "as symmetrical (and as sensitive) as a bird's wing". When touching the opposite arm with these feather fingers one can feel the touch on the left arm and of the fingers on the right hand moving as if to touch the left arm but it is instead the feathers which make contact. Rebecca Horn describes the effect: "it is as if one hand had suddenly become disconnected from the other like two utterly unrelated beings. My sense of touch becomes so disrupted that the different behavior of each hand triggers contradictory sensations." This piece focuses greatly on sensitivity. Sculpture Horn continued to explore the image of feathers in her works of the 1970s and 1980s. Many of her feathered pieces wrap a figure in the manner of a cocoon, or function as masks or fans, to cover or imprison the body. Some of these pieces are Cockfeather (1971), Cockfeather Mask (1973), Cockatoo Mask (1973), and Paradise Widow (1975). Various "machines" are the subjects of Horn's work in the 1980s. Among others, she created a machine to mimic the human act of painting in The Little Painting School Performs a Waterfall (1988). Thirteen feet above the floor on a gallery wall, three fan-shaped paint brushes mounted on flexible metal arms slowly flutter down into cups filled with blue and green acrylic paint. After a few seconds of immersion they snap backward, spattering paint onto the wall, the ceiling, the floor, and onto canvases projected from the wall below. The brushes immediately resume their descent, and the cycle is repeated until each canvas is covered in paint. In the 1990s a series of her impressive sculptures were presented in places of historical importance. Examples are the Tower of the Nameless in Vienna (1994), Concert in Reverse in Munich (1997), Mirror of the Night in an abandoned synagogue in Cologne (1998) and Concert for Buchenwald at Weimar (1999). In Weimar, the Concert for Buchenwald was composed on the premises of a former tram depot. The artist has layered 40 metre long walls of ashes behind glass, as archives of petrifaction. At the same time, the theme of bodily vitality, which the artist had been exploring since the seventies, was developed in site-specific installations that investigated the subject of the latent energy of places and the magnetic flows of space.