Why do we say "To turn the screw"?

Meaning:

To do something that makes a bad situation worse.

Background:

Dating back to at least the Victorian era, screw has long been a slang term for a prison guard. Some sources say that this is because screw was originally slang for key and thus the prison guards, the turnkeys, became known as screws.

However, a more specific source was offered in "What the Victorians Did For Us," a BBC Two documentary first broadcast in 2001. Back in the early Victorian era, there was little concept of prison as a place of rehabilitation, only of punishment. One such punishment was to crank a handle for hours on end. Given that the dynamo was invented in 1831 you might think that the cunning Victorians were putting the prisoners to work creating electricity but, no, the cranking was purely for punishment. The crank was attached to a box with a counter and the prisoner had to do 10,000 turns in 8 hours - about one turn every 3 seconds. To make the punishment more difficult, the prison guard could tighten the screw -- and, thus, we get the expression "to turn the screw," meaning to make a bad thing worse.


When setting the Wordplays, we always have a particular expression in mind but from time to time there are other valid answers. For example, in this case, "to turn the scales" or "to turn the situation." When this occurs, all valid answers are included when drawing the winning name.