Coin that Phrase: “Canary in a Coal Mine”

Many of us have Heard the Phrase, but what does it Really mean?

by Ali Khan, age 15

With their keen sense of impending danger, there’s more value to canaries than just their harmonious music.
As far back as the Industrial Revolution, canaries were used as a safety mechanism in coal mines. Because of the lack of high-tech ventilation systems, coal miners in the late 1700’s brought cages of canaries inside new coal seams.
Along with their vocal talents, canaries are especially sensitive to methane and carbon monoxide gases, which makes them helpful in detecting dangerous gas build-ups in coal mines. Other animals were occasionally used to test the air, but the canary had the strongest reaction to small concentrations of gases.
As miners worked, they listened to the serene melodies of canaries chirping. But as soon as the canaries stopped singing, the silence foretold potential danger. A dead canary was a signal for the miners to evacuate the coal mine immediately.
Although methane gas detection and coal mining technology has improved, mining companies used the canary method well into the 20th century. Today, the phrase “canary in a coal mine” is used as a metaphor referring to something that serves as a warning of danger. For example, private landowners have become the “canary in a coal mine” for cougar sightings in Wisconsin.
The innocent canary may have suffered its fate, but its silence often prevented the deaths of miners.

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This article was very interesting. I didn't know canaries were involved in coal mining sites and that they were very useful with the help they gave. I really liked this. – Amira Caire , Fitchburg, WI (2013-08-29 20:48)
I've never heard this phrase before but it's really interesting where it comes from. It makes me wonder about all of the other phrases that are out there! – Jenzl Guerrero , Madison, WI (2013-09-03 16:56)
Wow. Never knew that canaries were a tool in coal mining. Great job with the article! – Alex Lee , Madison, WI (2013-09-03 17:03)
wow great job! I didn't know canaries were used in coal mining or even what the phrase meant. Thanks for the info! – Nyataba , Madison, WI (2013-10-17 18:55)