Wasps and Ants 55 



reached. If a straw was laid across the path, 

 they dropped the load, and measured the straw 

 with their feelers, first one then the other. 

 Then they tried the ground to see if they could 

 go under the straw. If they could not, they 

 ended by picking up their burden, lugging and 

 tugging it to the top of the straw, and tumb- 

 ling it down on the other side. 



Blocking the path with a pebble, a pinch 

 of earth, even a splash of water was much 

 more serious. Ants gathered in knots either 

 side the obstacle, turning uncertainly about, 

 until a ranger came to lay out a new path 

 for them. The new path was almost always 

 around the obstacle, not over it. By wetting 

 the ground either side the path for a little 

 distance, it was possible to make the ants crawl 

 over a pebble. Loose earth they would not 

 set foot on a strange thing when one con- 

 siders that they nest so often in earth indeed 

 that they cannot live without earth. Where 

 a path was blocked continuously for a yard or 

 so, or two or three times close together, the 

 rangers abandoned it, and struck out a new 

 one. 



Joe fancied the ants followed their paths by 

 scent. This was because water in a path set 

 them at fault even after it had dried. He be- 

 lieved also the pathmakingwas in the nature of 

 a providence to help ant-swarms to their proper 



