Since the topic of canaries and gasses has arisen in this thread.... it came to mind.......I have been told that they used canaries in the coal mines to detect when the explosive gasses down deep in the mine had reached a level of danger.......the canary would die.....and the miner would get the hell out!!!

Do you suppose those canaries were freed from forced labor...??? Or was there just a run on canaries in 1903?