This collage returns to the theme of energy which Beuys explored many times. He has used a variety of everyday materials for this work, including acid and aluminium foil. Although these are traditionally unusual to include in an artwork, they are among many humble materials the artist favoured. In particular, the acid causes and represents decay, and Beuys would have used it to make this chemical process become part of the work. The three drawings on the pieces of paper which have been attached to the cardboard are presumably of components which are part of the 'motor' of the work's title.