Perhaps slightly off-topic, but may be of interest - the saying, 'cold enough to freeze the balls off a brass monkey' does indeed bring to mind images of personal anatomy, but the source is more prosaic.In sailing ship days and old-style naval warfare, cannon balls were kept stored ready for use in an open, egg-crate type grating, so that they wouldn't roll about with the ship's motion. These were usually wooden, but fancier ships of the line indulged in the luxury of brass ones. The grating was known as a 'monkey'.When some of these fancier ships sailed too close to the arctic/antarctic shores, it was found that the cannon balls started rolling all over the gun decks. The reason was that brass shrinks in the cold to a greater extent than iron - the size of the 'hole' therefore contracted, and the iron balls naturally could no longer be held in position.It did have to be very cold to produce this effect, hence the expression.
Nigel Moore ● 6459d