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allowed to ascend from the same spot, when it was 

 observed that each one moved in a different direction. 

 Clouds afterwards collected and obscured the sky, and 

 then our attempts to favour their ascent were un- 

 availing ; not one suceeded, and all fell like lead to the 

 ground." We felt some degree of gratification to find 

 that a similar phenomenon had been observed by 

 Mr. J. Thompson of Hull, under different circum- 

 stances : our observations were unknown to, and inde- 

 pendent of, each other: " On the 19th of July a 

 number of aeronautic spiders (at any rate, small black 

 spiders capable of flight,) by some means found their 

 way into St. John's church. Although not a proper 

 place for observations on natural history, there were 

 so many that, without shutting my eyes, I could not 

 fail noticing them. The tops of ladies' bonnets were 

 generally the places whence they commenced their 

 flight ; and in it they seem not to be confined to any 

 particular direction. Some flew upwards at a slight 

 angle ; some north, some south, some east, some west ; 

 and in so doing, several passed so near each other 

 that I cannot conceive, as they passed in opposite 

 directions, that any current of air conveyed them ; as 

 two opposite currents could scarce exist so often close 

 to each other." If the thread is shot horizontally, 

 they follow in that direction ; if vertical, in that plane : 

 the position of the thread remains. No current emanat- 

 ing from the earth can be supposed to act downward. 

 It is somewhat difficult to ascertain what purpose 

 their ascent in the atmosphere subserves ; but seeing 

 that the exuviae of gnats (culex pipiens) have been 

 found entangled in the meshes of the falling cobwebs, 

 in all probability they may thin the destructive ranks 

 of some such kindred annoyance, which if not destroyed 

 might descend upon us with all the envenomed ven- 

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