What metaphors are used in The Miserable Mill by Lemony Snicket?

Sir is a hard man, one who believes in the necessity of difficult, manual labor. His experiences as a child have shaped him into the man he is today, a man that pays his employees in coupons, gives them only gum for lunch and forces children to work in a mill. He feels that the experience of working in the mill will give the children a work ethic: a sort of metaphor for navigating life's rough spots.