The origins of English idioms can be interesting as well as having a certain entertainment value. It could be a literary device that misleads or confuses readers.
A RED HERRING: Something that confuses or distracts. Its origin, it has been stated, came from William Cobbett who told a story of having used a kipper (strong smelling smoked fish) to divert or trick dogs from chasing a hare.
COST AN ARM AND A LEG: Something that was very expensive.
In the 18th century if someone wanted a portrait painted the artist had to be given clear instructions as to what was wanted. The reason being that the cost would depend on how much of the human body was to shown in the painting.
PULL OUT ALL THE STOPS: To use all resources or force at one’s disposal.
This idiom refers to the organ – to play all the pipes to create the instrument’s fullest sound. Dated from around 1860.