** Phrase origins: "Cold enough to..."

Meaning

Very cold weather conditions.

Origin

Some references say that the brass triangles that supported stacks of iron cannonballs on sailing ships were called monkeys and that in cold weather, as brass contracts more than iron, the triangles contracted sufficiently for the balls to fall off.

This is nonsense but it so widespread a story that we need a little examination to help kill it off.

The young boys who helped with the loading of cannons on naval ships were called powder monkeys, but that's as far as monkey business goes on board ship. The Royal Navy records that, on their ships at least, cannonballs were stored in planks with circular holes cut into them. There's no record of these planks having been given a name - they certainly weren't called monkeys.

Also, a little geometry shows that a pyramid of balls will topple over if the base is tilted by more than 30 degrees. This tilting, not to mention any sudden jolting, would have been commonplace on sailing ships and it just isn't plausible that cannonballs were stacked this way.

For those wanting a bit more detail, here's the science bit. The coefficient of expansion of brass is 0.000019; that of iron is 0.000012. If the base of the stack were one metre long the drop in temperature needed to make the 'monkey' shrink relative to the balls by just one millimetre, would be around 100 degrees Celcius. It is hardly credible that amount of change would have the slightest effect. In any case in weather like that the sailors would probably have better things to think about.

The real origin is not so fanciful. If you've heard the phrase 'hear no evil, see no evil, speak no evil' you are probably familiar with the sets of sculptured brass monkey figures that have used as paperweights since at least the early 20th century. The term brass monkey itself has been in use that long too, as in The Story of Waitstill Baxter, Kate Wiggin, 1913:

"The little feller, now, is smart's a whip, an' could talk the tail off a brass monkey".

The sailing ship story has some romance but it is another of those dreamed up by CANOE (the Committee to Ascribe a Naval Origin to Everything). In reality, the phrase in question is just a colourful bit of language to the effect that "it's so cold that even an inanimate sculpture can feel the effects of it".