72 MECHANICAL FUNCTIONS. 



news being conveyed by the cord stretched between 

 them. If it proves to be some luckless fly, which has 

 caused the alarm, the voracious spider mounts the cord, 

 and in another instant, may be seen tying the legs, and 

 wings of its victim, with the utmost eagerness and art, 

 so as to prevent the possibility of escape. Having thus 

 secured its prey, it sucks its blood at leisure, and then 

 retires and waits for another haul. 



If craftiness, ingenuity and contrivance are not ex- 

 hibited in such proceedings as these, we know not where 

 to find them in the animal kingdom. Any one by 

 watching a common house Spider, may convince him- 

 self of the truth of our statement. 



The ingenuity with which spiders contrive to escape 

 when surrounded by water, is sometimes highly curious 

 and interesting. Mr. Kirby placed a large field spider 

 upon a stick about a foot long set in a vessel of water. 

 After fastening its thread, at the top of the stick, it crept 

 down the side until it came to the water, then immedi- 

 ately swinging from the stick which was slightly bent, 

 it climbed again to the top. This it repeated many 

 times, still finding its retreat cut off, and no means of 

 escaping in that manner. At length it let itself down 

 from the top of the stick, not by a single thread, but by 

 two, each distant from the other about the twelfth of an 

 inch, guided as usual by one of its hind feet, one of the 

 threads being apparently smaller than the other. When 

 it had suffered itself to descend nearly to the surface of 

 the water, it stopped short, and by some means not 

 apparent, broke off close to the spinners, the smallest 

 thread, which still adhering to the top of the stick, float- 

 ed in the air, and was so light as to be moved by the 

 slightest breath. This thread catching on an object at a 

 little distance, the spider employed it as a bridge to 

 make its escape. 



But the ingenuity and resources of this tribe of in- 

 sects are so well known, that we will not multiply more 

 instances. 



/ 



Ingenuity of the Caddis worm. A little insect, or 

 worm, common in fresh water brooks, called the Caddis 

 worm, and well known to anglers, builds for itself a 



