264 AIR. 



CHAPTER XIX. 



CARBONIC ACID GAS. 



Q. What is CHOKE DAMP ? 



A. Carbonic acid gas accumulated at 

 the bottom of wells and pits, which renders 

 them noxious, and often fatal. 



Q. Why is not this carbonic acid TAKEN UP 

 by the AIR, and DIFFUSED, as it is- in cities ? 



A. Because (being heavier, than com- 

 mon air) it cannot rise from the well or 

 pit ; and no wind can get to it to blow it 

 away. 



Q. Is CARBONIC ACID WHOLESOME? 



A. No; it is fatal to animal life, 

 when inhaled through the mouth ; acting 

 on the stomach, as a narcotic poison (i.e. 

 a poison which produces death from 

 drowsiness). 



Q. How can any one KNOW, if a place be 

 infested with CARBONIC ACID GAS ? 



A. If a pit or well contain carbonic 

 acid, a candle (let down into it) will be 



