John Green was brought in as ganger to hurry things up on the construction of the Crosshill section of the Glasgow-Edinburgh line, Cheshire-born Green, a tall, broad-shouldered fellow with a ruthless reputation, was known to have an intense dislike of Irishmen. One aspect of that reputation was that he always sacked at least one man on his first day at a new site to establish his reign of fear and intimidation. Within hours of his arrival his steely gaze alighted on Dennis Doolan. “You’re a slacker, Doolan,” Green said. The Irishman replied: “I was here before you came and I’ll be here after you’ve gone!” At that Green informed him that he was fired, effective from the following Saturday.
Reference:
http://www.truecrimelibrary.com/crimearticle/dennis-doolan-and-patrick-redding/