4292. No: it is fatal to animal life: and (whenever it is inhaled) acts like a narcotic poison—producing drowsiness, which sometimes ends in death.
4293. How can any one know if a place be infested with carbonic acid gas?
4294. If a pit or well contain carbonic acid, a candle (let down into it) will be instantly extinguished. The rule, therefore, is this—Where a candle will burn, a man can live; but what will extinguish a candle, will also destroy life.
4295. Why does a miner lower a candle into a mine before he descends?