52 Notice of the Rarer Atmospherical Phenomena in 1824. 



tially obscured by floating cumuli, there was observed in the 

 east, exactly opposite to the position occupied by the sun, nu- 

 merous luminous rays, diverging from a point apparently a 

 little below the horizon, and extending all round, so as to oc- 

 cupy the full half of the sky. These rays were very delicate, 

 yet perfectly distinct. Very shortly after they were first ob- 

 served, they vanished, when the etetnulus, which had veiled the 

 sun during their appearance, had somewhat altered its position. 

 But when this cloud had come near our zenith, another 

 phenomenon of the same nature occurred. This was a broad 

 conical ray darting horizontally from between the eminences 

 of the cloud, and extending to a considerable distance. The 

 ray was very vivid and distinct, and continued visible for 

 some time. The sky was apparently clear, but rather light- 

 coloured. The moon's unenlightened disk was very distinct- 

 ly seen all night. The phenomenon now described, is the 

 same as that which Dr Brewster saw in October, near 

 Edinburgh, and which he has noticed in the 3d number of this 

 Journal, under the name of " The Convergence of the Solar 

 Beams." Dr Brewster there states, that the appearance is 

 to be considered as a very rare one, since he is not aware of its 

 having been observed by any one, except Dr Smith, in Eng- 

 land, and, as he was informed by Mr Haidinger, Professor 

 Mohs at Freiberg. But, doubtless, many others have seen it, 

 although no account of their observations may have been pub- 

 lished, since the writer of this paper has observed it four 

 times in the course of three years : — in August 1822, June 

 1823, May 1824 (as now described), and on the 18th Ja- 

 nuary 1825 : and notice has been received of its having been 

 seen at Aberdeen in great beauty, in August last. 



June was remarkable on account of the long period of dry 

 weather which then occurred. Including a part of the pre- 

 ceding month, very little rain fell for about five weeks ; dur- 

 ing which, for the most part, high temperatures prevailed, 

 high pressure, light breezes from the east, and great dryness of 

 the air. The force of the sun's radiation was sometimes very 

 great. On the 2d, accurately observed, about noon, it was 

 found to be about 50°. 



Much has frequently been said about the correspondence in 



