Intelligence and Miscellanies. 199 



farm." Here is an error, committed by the compiler. The 

 locality exists in Cornwall, Vt. but not in Cornwall, in Conn. 



" Hornstone, Bridgeport," Con. " Hall." This should be Brid- 

 port^ Vt. 



There are many other errors of a similar nature, which I have 

 not time at present to look up. F. Hall. 



7. Aurora Borealis — Magnetic JVeedle, ^c. — Communicated by 

 L. D. Gale. — I noted in my private journal, some remarkable 

 phenomena of the Aurora Borealis, during- the 28th, 29th, and 

 31st of August, 1827, which I intended at that time to communi- 

 cate for your Journal ; but thinking that others more capable 

 than myself, would better describe the same, I neglected to com- 

 municate my observations. Seeing, however, no observations on 

 the magnetic needle, in the numerous notices in your Journal, 

 except that of M. Arago, who states, that "The Aurora Borealis 

 announced itself as early as 8 P. M. Tuesday 25th, by a very 

 perceptible disturbance of the horizontal needle's diurnal varia- 

 tions." But the phenomena observed by M. Arago, could not 

 have been the same observed in America, and described in your 

 Journal, unless there was a mistake in the date : because August 

 25th came on Saturday, whereas, the 25th of September carne 

 on Tuesday, which latter must have been the time referred to 

 by M. Arago, as a brilliant aurora was seen in this city the same 

 evening, which even obscured the light of the moon. 



When I first observed the luminous appearances of Tuesday,^ 

 August 28th, at 10 P. M. I placed a horizontal needle, delicately 

 mounted, in the window of my room, which was in the northern 

 side of the house, and a dipping needle about ten feet distant in 

 another window. On examination, I found that neither would 

 come to a state of rest. The mean of the extremes in the hori- 

 zontal needle, Avas at least 6° west of the magnetic meridian. 

 After marking the extremes on a paper card, fixed in the win- 

 dow for the purpose, I left it. The dipping needle which oscil- 

 lated from 64"^ to 7^^ was in constant agitation and very irregu- 

 lar in its motions ; sometimes rising to nearly 60° and remaining 

 for a moment with a tremulous motion, and then sinking back to 

 75° or 76°, having a mean dip of 69 1-2°, which is, 1 believe, 

 according to the best needles I have seen, 2 1-2° above the true 

 dip of this latitude. 



The greatest variation of the needles was at 10 P. M. when I 

 first placed them in the window, and it constantly decreased. 



The brilliancy of the Aurora increased till 10 o'clock 30 min- 

 utes, when it gradually ascended towards the zenith, and at the 

 same time diminished in brilliancy until 11 o'clock 30 minutes, 

 when its luminousness had entirely disappeared : though there 

 ■svas a bright Aurora in the northern horizon. 



