In 1968 McLean delivered a lecture at St Martin?s School of Art, London, in which he called for the reconsideration of sculpture in relation to the real environment. At this time his own work was very much in this vein; involving minimal interventions to natural situations. He created impermanent `sculptures? which were then photographed to act as a reminder of their somewhat transient existence. Despite McLean?s often comical pieces, such as `Glass on Glass on Glass on Grass?, behind them lies this desire to re-examine the notion of sculpture. In this case the sculpture was a sheet of glass on grass. It has, however, been photographed and transformed into another sculptural object by being displayed under a square of glass before being framed in a wood and glass frame.