Throughout the years, manacles have served as a common reference for comparison, as they portray a stark image of bondage. Though rarely used in contemporary everyday vernacular, the term "manacle" paints a vivid picture when alluded to in literature and other popular writing. Manacles are devices for confining the hands of a human being. Traditionally, they comprise a chain that links together two metal rings fastened together in such a way that the subject of confinement cannot escape. More often than not, the term "handcuffs" is used in reference to this purpose; handcuffs are actually a type of manacle.
When used in writing, the connotation of manacles is one of bondage. Writers may compare living conditions with manacles in reference to a harsh physical environment that is somehow limiting, or something more abstract such as the emotional or psychological surroundings that stunt a person's existence. Manacles convey a real or imagined sense of limitation when used in writing.
One of the most popular connotations of the term "manacle" in writing comes from the 18th century English poet William Blake. Blake makes reference to "mind forg'd manacles" in the second stanza of his poem "London," making an allusion to manacles in reference to the quality-of-life gap between the rich and poor during his lifetime in the city of London. He uses the term "manacle" to represent the confinement of the poor in their unfavorable circumstances --- a condition he sees as partially created in their own minds by ideas exerted upon them by external forces.
A more contemporary connotation of "manacles" comes from the late Nobel Prize winner and peace activist Dr. Martin Luther King Jr. In his famous "I Have a Dream" speech, Dr. King made reference to African Americans continuing to be "crippled by the manacles of segregation and the chains of discrimination." He made these comments in reference to the civil injustices of institutionalized discrimination African Americans suffered prior to the civil-rights reforms of the 1960s in the United States.