88 NATURAL HISTORY OF SELBORNE 



stitious as the notions about them were formerly, nobody 

 in these days doubts but that they are the real production 

 of small spiders, which swarm in the fields in fine weather 

 in autumn, and have a power of shooting out webs from 

 their tails so as to render themselves buoyant, and lighter 

 than air. But why these apterous insects should that day 

 take such a wonderful aerial excursino, and why their webs 

 should at once become so gross and material as to be con- 

 siderably more weighty than air, and to descend with pre- 

 cipitation, is a matter beyond my skill. If I might be 

 allowed to hazard a supposition, I should imagine that those 

 filmy threads, when first shot, might be entangled in the 

 rising dew, and so drawn up, spiders and all, by a brisk 

 evaporation, into the regions where clouds are formed : 

 and if the spiders have a power of coiling and thickening 

 their webs in the air, as Dr. Lister says they have [see his 

 Letters to Mr. Ray}, then, when they were become heavier 

 than the air, they must fall. 



Every day in fine weather, in autumn chiefly, do I see 

 those spiders shooting out their webs and mounting aloft : 

 they will go off from your finger, if you will 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 page, and shooting out a web, took it's 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 loco-motive power without 

 the use of wings, and to move in the air faster than the 

 air itself. 1 



possess the instinct to throw out silken threads upon which they may rise to great 

 altitudes and float for miles, blown before the wind, and such threads have been 

 met with many hundred miles from land ; and no doubt it is largely due to this 

 unique means of dispersal that many genera of Spiders are cosmopolitan in their 

 distribution, and have succeeded in making their way to the most isolated oceanic 

 islets. [R. I. P.] 



1 I reproduce the following comment by Sir Wm. Jardine (ed. "Selborne," 

 p. 186, note) : " Every sportsman must have noticed the appearance indicated in 

 the preceding letter. Lister, as above referred to, has some very good observa- 



