Hierarchy of Class:
This is a classic example of Pneumoconiosis, or ‘coal miners lung’. For the majority of the 20th century, doctors and mining companies claimed that coal dust protected miners from tuberculosis. A major report by American statistician Frederick Hoffman refuting this claim achieved nothing. The nation’s response to this crisis was best summed up by Penn State University professor Alan Derickson, as “a public health disaster.” Working men were coughing up black phlegm and most were out of work before age 45, but it took until 1974 for any legal change to come about.
How does this fit into your idea of hierarchy?
Source: Lot 7, UCL Pathology Museum, Royal Free Hospital