MOUNTAINS. DIVERS. 255 



Q. Why is it often PAINFCL, and difficult to 



BREATHE, OU a MOUNTAIN top ? 



A. Because the pressure of air on 

 the mountain top is not so great as on the 

 plain; and the air inside our bodies 

 (seeking to become of the same rarity) 

 bursts through the pores of the body, and 

 produces great pain. 



Q. Why do we feel OPPRESSED just PREVIOUS 

 to a STORM? 



A. Because the air is greatly rarefied 

 by heat and vapour ; and the air inside us 

 (seeking to become o the same rarity) 

 produces an oppressive and suffocating 

 feeling. 



Q. Why do DIVERS suffer great pain in their 

 eyes and ears under water ? 



A. Because the air at the bottom of 

 the sea is more dense than the air on the 

 surface; and while the air inside the 

 diver's body is settling into the same 

 density, he feels oppressed with pain, 

 especially in the ears. 



Q. Why is this PAIN felt especially about the 



EARS Of a DIVER ? 



A. The ear is fitted with a small 



z 2 



