234 NATURAL HISTORY. [cH. XIV. 



spinners against one of the sides, and glues to it 

 one end of the thread. The insect proceeds from 

 one side, as far as the place to which it intends to 

 extend its web, while the thread lengthens in the rear. 

 The thread is fastened to one of the spurs or claws 

 with which the spider's feet are furnished, lest it 

 should come in contact with the wall while it is in- 

 tended that it should traverse the air. When the 

 insect has reached the point on the opposite side to 

 which it purposes to continue the web, it there 

 fastens this first thread by means of glue ; it then 

 pulls the thread, and renders it tight. Close by this 

 thread another is fixed, which the insect carries for- 

 ward by running along the first, like a tumbler on 

 his rope. The second thread is glued on one side 

 of the point where the work was begun. The first 

 two threads are used like a scaffold to assist in build- 

 ing all the rest. All the threads are stretched and 

 fastened, one after another, with equal art and in- 

 dustry, and the whole is executed with wonderful 

 expedition. 



Those threads which are destined to form the 

 outer margin or selvage of the web require addi- 

 tional strength; and for this purpose they are tripled 

 or quadrupled by a repetition of the operation just 

 described. From these marginal threads others are 

 spun in various directions ; the interstices are filled 

 up by threads spun by the spider as it runs from one 

 to the other, until the whole, when finished, assumes 

 the gauze-like texture which excites our admiration. 



These webs present merely a horizontal surface ; 

 but to those which are formed in out-houses or among 

 bushes in the open air, a very ingenious appendage 

 is added. From the edges and surface of the main 

 web the spider carries up a number of single threads, 

 often to the height of many feet, meeting and cross- 

 ing each other in various places. Jn their arrange- 

 ment, these lines are not unlike the tackling of a 

 ship; and in their (light across them, the flies become 



