38o 



THE WORLD OF ANIMAL LIFE 



the tip of this organ the object to which the end of the line is to 

 be fastened, and drawing its body rapidly away, a delicate thread 

 is formed, which hardens as it is made. 



This thread is wonderfully strong, and will support a much 

 heavier weight than one would imagine. The secret of its strength 



Spidei taadij^eiij;^^ 



is, that it consists, not of a single line, but of a number of slender 

 strands all closely twisted together. Each spinneret is pierced, not 

 by one large hole, but by a multitude of small ones. The silk 

 is forced simultaneously through all these holes, so that a large 

 number of exceedingly delicate threads are formed. And as the 

 body is drawn away, these are all twisted together into a single 

 strong line, just as is done in the manufacture of ropes. 



Taken individually, these threads have but little strength, but 



