Well although there was snow on the ground this morning, I don’t know that it was cold enough to freeze the tail, ears, hair or anything else off a brass monkey, but I came across the following:
Quote:
The "brass monkey" is in fact the nickname given to a ship's binnacle, the brass housing for the compass. The "balls" are the "quadrantal spheres" or soft iron balls mounted on either side of the binnacle. These were devised by Lord Nelson of the British Admiralty.
The balls, combined with a soft iron bar (a Flinders Bar) mounted vertically on the binnacle and hard magnets found inside the housing, are all used to minimize deviation of the compass due to the Earth's and the ship's magnetic fields. This process is called "boxing" the compass.
Does anyone believe any of this? Is a brass monkey a ship’s binnacle? Did Nelson have anything to do with quadrantal spheres?
I doubt very much whether the expression even has a nautical origin at all. A brass monkey seems to have been used as a common expression for someone or something unfeeling, whether emotionally or physically. 19th C uses include:
… They'd have stirred a brass monkey to passion …
… hearts, hands, feet and flesh are as cold and senseless as the toes of a brass monkey in winter …
… hot enough to melt the nose off a brass monkey …
… cold enough to freeze the tail off a brass monkey …
… sufficient, as the saying is, to scorch the brains of a brass monkey …
… T’would fetch a fair grin from a blessed brass monkey …
… It is hot enough to scald the throat out of a brass monkey …
… would talk the ears off a brass monkey …
… it would kindle the indignation of a brass monkey …
… a face as hard as a brass monkey …
… cold enough to freeze the ears off a brass monkey …
Even allowing for euphemisms there doesn’t seem to be much evidence for cannon balls or quadrantal spheres.