Canary in a coal mine...
I've used that phrase often and tonight hpylady_ suggested it on Jim's blog about virus being carried on tiny particles found in air pollution.The concept of a canary in a coal mine is because miners had died as the levels of colorless odorless carbon monoxide, methane or other gases that proved to be fatal to the miners. They had no means of detecting these hazardous/toxic gasses and found that canaries would quickly sicken when subjected to that kind of environment allowing the miners to escape unharmed.
Using canaries became an 'early-warning' system for the workers deep inside the mines.
It wasn't until years later they carried compressed air breathing systems and carbon monoxide detectors to protect miners.
The birds were no longer needed but the saying is still around...
The idiom/metaphor 'Canary in a coal mine' also relates to other things, such as financial indicators. For example: Mortgage borrowers in this coronavirus pandemic could be the canary in the mine to a foreclosure crisis.
Comments (5)
Was there any other lyrics, besides "canary in a coal mine" ?