MOTIONS OF INSECTS. 



271 



darted forth a long thread, and vaulting from the place on 

 which it stood was carried upwards to a considerable height. 

 Numerous observations afterwards confirmed this extraor- 

 dinary fact ; and he further discovered that while they fly 

 in this manner, they pull in their long thread with their fore 

 feet, so as to form it into a ball -— or, as we may call it, air- 

 balloon — of flake. The height to which spiders will thus 

 ascend he affirms is prodigious. One day in the autumn, 

 when the air was full of webs, he mounted to the top of the 

 highest steeple of York minster, from whence he could dis- 

 cern the floating webs still very high above him. Some 

 spiders that fell and were entangled upon the pinnacles he 

 took. They were of a kind that never enter houses, and 

 therefore could not be supposed to have taken their flight 

 from the steeple. 1 It appears from his observations that 

 this faculty is not confined to one species of spider, but is 

 common to several, though only in their young or half-grown 

 state 2 ; whence we may infer that when full-grown their 

 bodies are too heavy to be thus conveyed. One spider he 

 noticed that at one time contented itself with ejaculating a 

 single thread, while at others it darted out several, like so 

 many shining rays at the tail of a comet. Of these, in Cam- 

 bridgeshire in October, he once saw an incredible number 

 sailing in the air. 3 Speaking of his Ar. subfuscus minu- 

 tissimis oculis, &c, he says, " Certainly this is an excellent 

 rope-dancer, and is wonderfully delighted with darting its 

 threads : nor is it only carried in the air, like the preceding 

 ones ; but it effects itself its ascent and sailing : for, by 

 means of its legs closely applied to each other, it as it were 

 balances itself, and promotes and directs its course no other- 

 wise than as if nature had furnished it with wings or oars." 4 

 A later but equally gifted observer of nature, Mr. White, 

 confirms Dr. Lister's account. " Every day in fine weather 

 in autumn," says he, " do I see these spiders shooting out 

 their webs, and mounting aloft: they will go off from the 



1 Ray's Letters, 37. 87. Lister, Be Aran. 80. Lister illustrates the force 

 with which these creatures shoot their thread, by a homely though very forcible 

 simile : " Resupinata (says he) anum in ventum dedit, filumque ejaculata est 

 quo plane modo robustissimus juvenise distentissima vesica urinam." 



2 Be Araneis, 8. 27. 64. 75. 79. 3 Ibid. 79. 4 Ibid. 85. 



