MOTIONS OF INSECTS. 465 



where he also alludes to the old opinion of scorched dew. But the first 

 naturalists who made this discovery appear to have been Dr. Hulse and 

 Dr. Martin Lister the former first observing that spiders shoot their 

 webs into the air ; and the latter, besides this, that they were carried upon 

 them in that element. 1 This last gentleman, in fine serene weather in 

 September, had noticed these webs falling from the heavens, and in them 

 discovered more than once a spider, which he named the bird. On an- 

 other occasion, whilst he was watching the proceedings of a common 

 spider, the animal, suddenly turning upon its back and elevating its anus, 

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

 was carried upwards to a considerable height. Numerous observations 

 afterwards confirmed this extraordinary 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 pro- 

 digious. 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 

 discern 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. 2 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 half-grown state 3 ; 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 Cambridgeshire in October, he 

 once saw an incredible number sailing in the air. 4 Speaking of his Ar. 

 subfuscus minutissimis 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." 5 A later but 

 equally gifted observer of nature, Mr, White, confirms Dr. Lister's ac- 

 count. " 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 finger if you take them into your hand. Last summer one alighted 

 on my book as I was reading in the parlour ; and running to the top of 

 the p;ige and shooting out a web, took its departure from thence. But 

 what I most wondered at was, that it went off with considerable velocity 

 in a place where no air was stirring ; and I am sure that I did not assist 

 it with my breath. So that these little crawlers seem to have while 

 mounting some locomotive power without the use of wings, and move 

 faster than the air in the air itself." 6 A writer in the last number of 



1 Ray's Letters, 36. 69. 



2 Ray's Letters, 37. 87. Lister, De 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 declit, filumque ejaculata est quo plane modo 

 robustissimus juvenis e distentissima vesica urinam." 



s De Araneis, 8. 27. 64, 75. 79. 4 Ibid. 79. 5 Ibid. 85. 



6 Nat. Hist. i. 327. 



II H 



