Brass monkey weather

[Sylvester]

What does it mean? Where does it come from?

[andy hughes]

The phrase in its original form is "Cold enough to freeze the balls off a brass money." It doesn't, as popularly believed, refer to a metal simian, but dates back to the days of sailing ships, when cannon balls were placed in pyramid formation on deck, ready for action. To keep the balls in place, a brass ring, known as a 'monkey' was bolted to the deck, and the pyramid of cannon balls built inside it. In severely cold weather, the brass would contract, and as a measure of how cold it was, if the 'monkey' contracted enough for the cannon balls to roll off, it was indeed 'Cold enough to freeze the balls off a brass monkey."