At the bottom of the staircase is a linotype machine ( "line casting" machine) used in printing. Along with letterpress printing, linotype was the industry standard for newspapers, magazines and posters from the late 19th century to the 1960s and 70s, when it was largely replaced by offset lithography printing and computer typesetting.

This is a nod to Dundee's '3 Js', Jute, Jam and Journalism. DC Thomson is a Scottish publishing and television production company best known for producing The Dundee Courier, The Evening Telegraph, The Sunday Post, Oor Wullie, The Broons, The Beano, The Dandy, and Commando comics.
Courtesy of en.wikipedia.org/wiki/DC_Thomson