616 APPENDIX. 



December 18th. — At 10 h p. ; m., on going to the 

 needle, which, from its having been steady at zero at 4 h 

 p.m., and at 0° 10' W. at 7 h p.m., I expected to find 

 at zero again, I was surprised to observe, on the con- 

 trary, that it was at 1° 50' W., from which it moved to 

 1° 25' W., and then continued to vibrate gently between 

 that and 1° 35' W. The sky was perfectly clear, with 

 the exception of a horizontal light cloud due N., but 

 which had not the appearance of those dark grey or 

 light filmy clouds, that seemed on certain occasions 

 to influence the needle. The moon was bright, and as I 

 had, according to custom , looked carefully for aurora 

 without detecting any, before entering the observ- 

 atory, I was the more puzzled to account for such an 

 eccentric movement in the needle, without any apparent 

 disturbing cause. At the moment it occurred to me, 

 that the clear shining of the moon, which was at N. E., 

 and the fineness of the night altogether might prevent 

 me from distinguishing any rays or beams that might 

 nevertheless be flitting about. I therefore looked again 

 from different points around the observatory, but without 

 perceiving the least vestige of aurora, and consequently 

 thought it might be attributable to the continuance of 

 the westerly wind ; for during its prevalence, for three 

 days past, the needle had shown a disposition to keep 

 to that quarter : but on getting in the dark shade of the 

 house on my return, I immediately saw two reddish rays 

 and a long slender beam at S.W. projecting towards the 

 zenith, neither of which was visible in the moonlight or 

 out of the shade. This appeared to answer for the deflec- 

 tion, of the needle, and to give some clue to its frequent 

 disturbance during the day, as has been already noticed. 



December 21st. — The needle had been moving al- 

 most all day, the weather extremely cold to the sensa- 

 tion owing to a fresh breeze from S.W., attended by a 



