British Association for the Advancement of Science. 19 



ceiver. — Mr. Adams confirmed the statements made by Prof. 

 Henry as to the illuminating effects of the lateral discharge ; he 

 had once seen upon the discharge of a large electrical battery, a 

 wire splendidly illuminated by the lateral discharge, and exhibit- 

 ing the coruscations spoken of by Prof. Henry. 



Au9'ora in Summer. — Prof. Christie then made a communica- 

 tion ' on the occurrence of the Aurora Borealis in summer.' 



The occurrence of an aurora borealis in England, in the middle 

 of summer, was, he believed, a phenomenon hitherto unrecorded. 

 He then gave an account of several very striking exhibitions of 

 this phenomenon, which he had observed during the last summer. 

 One, on the 19th of May, 1837, presenting two bands of arches, 

 radiating from the magnetic west, and extending nearly to the 

 opposite horizon, was unaccompanied by streamers. Another, on 

 the 24th June, exhibited the usual appearance of coruscation from 

 the northern horizon, but no arches were visible. This aurora, 

 which was the most singular from being observed in the very 

 middle of summer, lasted from llh. 46m. until 12h. 20m. P. M. 

 Other auroras were observed on the 1st. 2nd, and 7th of July, and 

 25th of August. On the last occasion, the author noticed a sin- 

 gular phenomenon, which he had, on one occasion many years 

 previous, observed, namely, that the darkness usually attending 

 an aurora appeared to break into the light above it. He noticed 

 that, on the former occasion, he observed the darl^ness to rash 

 through, and finally break up, two well-defined arches of white 

 light ; and recalled to the Section, that Capt. Back had described 

 a very striking exhibition of a similar phenomenon, Avhich he 

 witnessed during his wintering at Fort Reliance. He particularly 

 called attention to these and other phenomena, of the darkness 

 exhibited in the aurora borealis, in connexion with the arches of 

 light and the more brilliant coruscations. After recurring to other 

 auroras which he had observed during the last summer, he inferred 

 that it was probable that the aurora borealis was as frequently in 

 activity in summer as during other seasons, though it might be 

 less frequently visible. The author further stated, that during 

 the last twelve months, no period of a month had elapsed without 

 the exhibition, in the south of England, of one or more auroras ; 

 and pointed out the importance of inquiring into the cause of 

 the now so frequent occurrence of a phenomenon, which some 

 years back had been very rare. He concluded by expressing a 



