PURE AIR 117 



admitted, it will begin to revive, but if the air is not 

 renewed, it will finally die. 



From these simple experiments three facts can be 

 readily seen. The first is that oxygen is needed in the 

 body to burn the waste tissues and generate necessary 

 heat and energy. The second, that the union of 

 oxygen and our bodily tissues produces carbonic acid 

 gas, which must not remain long in the body because 

 it is poisonous. The third, that the body rids itself 

 of much of this poisonous gas by expelling it with the 

 air that is breathed out of the lungs. 



It is not a very difficult problem in arithmetic to 

 calculate the mighty task our heart and lungs perform. 

 If, as is estimated, two ounces of blood are sent to 

 the lungs by each contraction of the heart, and there 

 are about seventy heart beats a minute, 201,600 ounces, 

 or about twenty-five hogsheads, of blood are daily 

 driven through the lungs to be purified. Breathing 

 in thirty cubic inches of air at each breath eighteen 

 times a minute, twenty-four hours a day, 777,600 

 cubic inches, or upwards of fifty-three hogsheads, of 

 air are daily breathed into the lungs. 



Are we assisting these hard-working organs in their 

 prodigious task by doing all in our power to have the 

 air we breathe as pure as possible ? Certainly few 

 things can count more toward health and happiness 

 than fixing the habit of having the air we breathe as 

 pure as conditions will permit. 



