This area of the Blackburn Valley was described by Miller writing in 1936 as "a wide stretch of meadow land, over which the factories are gradually spreading" (Miller 1949, 99). Indeed the factories first depicted on the 1938 OS 25 inch mapping are by 1952 plans SK3892NW and 3893SW approaching total coverage with the Blackburn Brook confined to an artificial channel to the south west of the large shed type steel mills and works. Invisible legibility of earlier landscapes at this large scale steel complex.