How Animals Work. 



one of the points selected for the attachment of a foun- 

 dation thread, and then she will walk away trailing 

 behind her a thread which she keeps free from entangle- 

 ment with objects in her path by the guiding action 

 of one of her hind legs. On reaching the next desirable 

 point of attachment, the spider makes the foundation 

 line taut and fixed by again rubbing her spinnerets 

 against the spot selected. This process is repeated 

 again and again, until the framework of founda- 

 tion lines, which may be braced in certain places by 

 shorter lines attached to leaves and twigs close at hand 

 to prevent sagging, is completed. The spider pays the 

 greatest attention and care to these first foundation lines, 

 making sure that they are strong and well secured ; for 

 they will have to bear the strain of the web when it 

 is blown by the wind, or when heavy insects fly into 

 it and struggle violently to escape. But Madam Spider 

 does not often select such a convenient site as to be 

 able to crawl from branch to branch with her founda- 

 tion thread in tow. Indeed, more often than not 

 there are gulfs to be bridged over that would be quite 

 impassable in the ordinary way. But she is in no way 

 disconcerted by this state of affairs, but at once has 

 recourse to the aid of the wind. No, she does not 

 weave an air-raft and float across the intervening space 

 upon it, but having fastened her foundation cable to 

 the last- suitable point of attachment, she erects her 

 spinnerets and flings out threads into space ; the silken 

 threads carried by the air currents are borne across 

 the gap, and soon become entangled in some neigh- 

 bouring object. When this has happened, the spider 

 at once hauls the new line taut, and tests its strength 



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