124 CONVERSATIONS ON 



" This is very wonderful : but you said some- 

 thing about large trenches or gutters under- 

 ground ; what are they, Uncle Philip ?" 



" These galleries lead from the city under 

 ground, and are as large as the bore of a large 

 cannon ; they are thirteen inches across, and 

 more than a hundred yards long. I have 

 already told you that the labourers never come 

 out into the light, when they can help it ; and 

 these underground ways are the great roads 

 to the city, to fetch in clay, or wood, or water, 

 or provisions : and now I will tell you an- 

 other thing which shows a great deal -of sense. 

 As some of their houses are very high up, you 

 know they would find it very hard to climb 

 up through all the streets with a heavy load 

 in a straight line ; so when these large ways 

 underground reach the outside wall, they just 

 come through and keep on winding around 

 the inside of it like a corkscrew all the way 

 to the top ; and there are other galleries open- 

 ing from it at different places into the city. 

 One thing has been noticed about these ants ; 

 they can scarcely climb at all up a perpen- 

 dicular wall. Therefore on the upright 

 side of any part of the city you may see a 

 road made, standing out from the wall like 



