NATURE'S IMPLEMENTS 



one idea to the exclusion of all else. It goes to and fro 

 about its work until other ants realize the plan of it. 



In another part of the same ant-hill there were several 

 pieces of straw which appeared to have been placed there 

 expressly to form the roof of a large chamber ; a workman 

 took advantage of the way they were disposed, which was in 

 the form of an oblong lying horizontally half an inch from 

 the ground. The industrious insect began placing earth in 

 the angles of this framework and along the little beams of 

 which it was composed, afterwards adding row after row of 

 the same material until a distinct roof appeared. Perceiv- 

 ing then that it could take advantage of another plant to 

 support a vertical wall, it began laying the foundation of 

 one. By this time other ants had come upon the scene, and 

 they helped in the completion of the work. 



From these observations and a thousand others of the 

 same kind, I am convinced that each ant acts independently 

 of its companions. As soon as one hits upon a plan easy to 

 carry out, it makes a sketch of it, and then the others only 

 continue what the first has begun, judging what they should 

 do from an inspection of that part of the work which has 

 already been carried out. They all know how to make a 

 beginning, how to carry on the work, how to retouch and 

 give a finish to it as occasion requires. Water furnishes 

 them with the necessary cement, and the sun and air harden 

 the material of their dwellings. They have no other chisel 

 than their jaws, no other compass than their antennae, 

 and no other trowel than the fore feet which they use in 

 such an admirable manner to lay down and make firm the 

 moistened earth. 



These, then, are the material and mechanical means which 

 ants employ in their building. If, as might have been the 

 case, they had simply obeyed a mechanical instinct, they 



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