On the Aerial Sjnder 323 



darted forth, from within the room, a lengthened thread diago- 

 nally upwards, and thus effected its ascent ; a fact at complete 

 antipodes with Mr. Black wall's opinion. 



The number of the aeronautic spiders occasionally suspended 

 in the atmosphere, I believe to be almost incredible, could we 

 ascertain their amount. I was walking with a friend on the 

 9th, and noticed that there were four of these insects on his 

 hat, at the moment there were three on my own ; and from the 

 rapidity with which they covered its surface with their threads, 

 I cannot doubt that they are chiefly concerned in the produc- 

 tion of that tissue which intercepts the dew, and which, illu- 

 minated by the morning sun, " glitters with gold,' and with 

 rubies and sapphires.'* Indeed, I have noticed that," when the 

 frequent descent of the aeronautic spider was determined, a 

 newly rolled turnip field was, in a few hours, overspread by a 

 carpet of their threads. It may be remarked that our little 

 aeronaut is very greedy of moisture, though abstemious in 

 other respects. Its food is perhaps peculiar, and only found 

 in the superior regions of the sky. Like the rest of its tribe, 

 it is doubtless carnivorous, and may subserve some highly 

 important purpose in the economy of Providence ; such, for 

 instance, as the destruction of that truly formidable, though 

 almost microscopically minute • insect, the Fiiria infernalis, 

 whose wound is stated to be mortal. Its existence has been 

 indeed questioned, but by no means disproved ; that, and some 

 others, injurious to man, or to the inferior creation, may be its 

 destined prey, and thus our little aeronaut, unheeded by the 

 common eye, may subserve an important good. 



As connected with this question, I may mention that the 

 electrical strata of the atmosphere, on Sunday the 6th inst., 

 was singularly illustrated in the curious configurations of the 

 dust on the pavement, being exhibited in a plumose form, 

 resembling the figures described on a plate of rosin when 

 touched by an electrified substance, and powdered rosin or 

 sulphur, &c., is projected against them : an experiment we 

 owe to Professor Lightenberg ; while, I believe, the late Dr. 

 Millar, of Edinburgh, was the first to notice these very inte- 

 resting arborescent forms of dust, and refer the phenomenon 

 to electricity. I noticed, also, on that day, that these confi- 

 gurations had their feathery image and impress in the sky, 

 several of the clouds presenting that plumose form. 



I now beg to quote an extract from a communication on 

 the subject of the gossamer spider, made to me by my friend, 

 J. E. Bowman, Esq. F.L.S. ; and I shall at present content 

 myself with it, not wishing to anticipate what may elsewhere 

 appear on this subject. " We arrested several of these little 



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