SOO STRANGE APPEARANCE 



compared, and for some time their relative means 

 were taken ; but afterwards that plan was relin- 

 quished, and the nearest mean thermometers were 

 adopted as standards for the whole. The daily- 

 variation instrument, made by Jones, on a plan 

 of Professor Christie's, to be explained hereafter, 

 was also adjusted in the magnetic meridian, and 

 its readings registered ten times a day, between 

 eight in the morning and midnight. The tem- 

 peratures were noted fifteen times in the twenty- 

 four hours. 



A short time after the needle was placed, 

 there was a strange appearance connected with 

 the aurora, and which, though it will probably be 

 again mentioned when I come to treat of that 

 subject expressly, I may perhaps be excused, on 

 account of its singularity, for noticing in this 

 place also. At 5 b 30 m p. m., while occupied 

 in taking the transit of a star, I perceived the 

 coruscations streaming from behind a detached 

 and oblong dark cloud in a vertical position at 

 E. b. S. * They issued along an undulating 

 arch 38° high, and spread themselves laterally in 

 beams north and south. Another arch, brighter 

 and narrower than the former, suddenly emerged 

 from W. b. N., and passed between a nearly 

 horizontal black cloud and the stars, which were 



* Magnetic bearing. 



