72 HISTORY OF INSECTS. 



ated in every direction as full of holes as the timber in the 

 bottoms of ships which has been bored by the worms ; the 

 fibrous and knotty parts being left to the last. 



In carrying on this business they sometimes find, by 

 some means or other, that the post has a certain weight to 

 support, and then, if it is a convenient track to the roof, or 

 is itself a kind of wood agreeable to them, they bring their 

 mortar, and as fast as they take away the wood replace the 

 vacancy with that material, which being worked together 

 by them closer and more compactly than human strength 

 or art could ram it, when the house is pulled to pieces, the 

 posts formed of the softer kinds of wood are often found 

 reduced almost to a shell, and all or most of them trans- 

 formed from wood to clay, as solid and as hard as many 

 kinds of free-stone used for building in England. When 

 the hills are more than half their height, it is the practice of 

 the wild bulls to stand as sentinels upon them while the 

 rest of the herd is ruminating below. 



