STRENGTH OF WEBS AND POWER OF SPIDERS. 233 



and perfectly pliable, was furnished, and this material connection be- 

 tween the wire cross and the clock pendulum proved to be exactly the 

 thing required. In proof of this remark I need only state the fact that 

 one single spider's web has fulfilled the delicate duty of moving the wire 

 cross, lifting it and again permitting it to dip into the mercury every sec- 

 ond of time for a period of more than three years ! How much longer 

 it might have faithfully performed the same service I know not, as it then 

 became necessary to break this admirable bond, to make some changes in 

 the clock. Here it will be seen that the same web was expanded and 

 contracted each second during the whole period, and yet never, so far as 

 could be observed, lost any portion of its elasticity." 



De Laet, 1 in his Xovus Orbus, as early as A. D. 1633 speaks of certain 

 beautiful spiders, elegantly marked by various colors, which build nets 

 strong enough to entrap small birds. Of others, or perhaps the same spe- 

 cies, he says that their webs are so tough that they can scarcely be broken. 2 



Sir Hans Sloane 3 describes a West Indies spider, which he calls the 

 " Great Yellowish Wood Spider," and which is undoubtedly a species of 

 Xephila, perhaps N. clavipes or N. plumipes, as making a web 

 Strength s t rO ng enough to ensnare birds. " They have," he says, " an 

 g 1 almost spiral large Web made of Yellow Spider's Thread, like Silk, 



glutinous or viscid, with which it will stop not only small Birds, 

 but even wild Pigeons ; they are so strong as to give a Man inveigled in 

 them Trouble for some Time with their viscid sticking Quality." He also 

 cites "Smith of Bermudas" (page 172) as describing "certain spiders of a 

 large size, not dangerous, but making a sort of raw silk, catching birds 

 bigger than blackbirds and like snipes, in their nets." 



Wallace, speaking of the spiders of the Aru Islands, in the Malay 



Archipelago, says that the web spinning species were a great annoyance, 



stretching their nets across the footpaths just about the height of his 



face ; the threads composing which were so strong and glutinous as to 



require much trouble to free one's self from them. 4 Mr. Mosely, the 



naturalist of the "Challenger," says that at Little Ke Island, 



' s one of the same group, "Yon Willemos Suhn actually found 



Birds a s t ron g> healthy 'glossy Starling' (Calornis metallica), caught 



fast in a Yellow spider's web, and he took the bird out alive 



and brought it on board the ship to be preserved." 5 



Vinson gives like testimony from observations made in the African 

 Island of Reunion. The young spiders that encamp in innumerable 



1 Xovus Orbus lonne de Laet, Ao. 1633, page 29. " Aranese * * * quse sestate ita 

 validas telas nent, ut minores aviculse illis irretantur." 



2 " Qui telas nent ita pertinaces ut vix disrumpi possint." Id., page 673. 



3 Natural History of Jamaica, Vol. I., page 196, A. D. 172o. 



4 The Malay Archipelago, Alfred Russel Wallace, page 437. 



5 A Naturalist on the " Challenger," page 382. 



