In this image, the children of the Cotton mill are juxtaposed with the industrial surroundings.  The dominance of grey in this image represents the dull monotony of their lives. 
The children huddle together, for warmth and emotional comfort, with the dog guarding them. The middle child has her hands clutched together, as if in prayer, while the oldest boy has to take on a world of adult responsibilities. 
The industry of Hebden bridge looms over the children, showing how there is no escape. It was virtually impossible for cotton mill children to leave. Those who tried would face harsh punishment from the mill owners as a warning to the others.
While the children are foregrounded and consequently a focal point, they are off centre, showing how they are on the edge of society.