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Insect Architecture. 



hill, which is flat on the upper surface and half an inch wide, 

 and ascends gradually like a staircase, or like those winding- 

 roads which are cut on the sides of hills and mountains, that 

 would otherwise be inaccessible ; by which and similar con- 



trivances they travel with great facility to every interior 

 part. 



This, too, is probably the cause of their building a kind of 

 bridge of one great arch, which answers the purpose of a 



