216 LETTERS ON NATURAL MAGIC. 



heard like the sound of cannon on the surface of 

 the earth, and the whole air is often violently 

 agitated by the sound. This fact alone may give 

 us some idea of the tremendous nature of the 

 forces which such explosions create, and it is 

 fortunate for our species that they are confined 

 to the upper regions of the atmosphere. If the 

 same explosions were to take place in the dense 

 air which rests upon the earth, our habitations 

 and our lives would be exposed to the most 

 imminent peril. 



Buildings have often been thrown down by 

 violent concussions of the air, occasioned either 

 by the sound of great guns or by loud thunder, 

 and the most serious effects upon human and 

 animal life have been produced by the same 

 cause. Most persons have experienced the stun- 

 ning pain produced in the ear, when placed near 

 a cannon that is discharged. Deafness has fre- 

 quently been the result of such sudden concus- 

 sions, and, if we may reason from analogy, death 

 itself must often have been the consequence. 

 When peace was proclaimed in London, in 1697, 

 two troops of horse were dismounted and drawn 

 up in line in order to fire their volleys. Opposite 

 the centre of the line was the door of a butcher's 

 shop, where there was a large mastiff dog of 

 great courage. This dog was sleeping by the 

 fire, but when the first volley was fired, it im- 

 mediately started up, ran into another room, and 

 hid itself under a bed. On the firing of the 

 second volley, the dog rose, ran several times 

 about the room trembling violently, and appa- 

 rently in great agony. When the third volley 

 was fired, the dog ran about once or twice with 





