Originally Posted by vincent
Run with it Doc!!
*grabs popcorn and prepares to be regailed yet again with origins of nautical terms*
Back in the days of wooden ships and iron men...
On the gun decks cannon balls were arranged in pyramid shaped stacks on s brass plate with indentations or holes cut in them to keep the foundation layer of cannon balls from rolling around as the ship would pitch in the sea. These plates were referred to as brass monkeys. Brass and iron being metals if differing densities would expand and contract at different rates as temperatures would change. Brass contracts considerably more and faster than iron. When temps got cold enough the holes or indentations would contract to a small enough diameter that they would force the still larger iron balls up and off the plate, sending them rolling around the gun deck. Thus the weather had gotten cold enough to freeze the balls off of a brass monkey.
Learned while touring the USS Constitution in Boston Harbor.