Agnes by Tony Cochran for February 03, 2009

stpatme – You are correct about the balls. The rest of the story is that the plate that they are stacked on is called a ‘monkey’. The problem was that the iron monkey would contract in cold weather and expand in hot, causing the balls to fall off the plate. So, to cure the problem, the monkey was made from brass as it didn’t contract as easily. But, when it got cold enough for the brass monkey to contract and the balls to roll off, it was mighty cold. “Cold enough to freeze the balls off a brass monkey”!!!

As far as I know, there is no similar explanation for the use of a “Witch’s Titty” to be an instrument by which to measure coldness!