No. III.] 



Dr. RICHARDSON ON THE AURORA. 



599 



when the cushion of an electrifying machine rubs hard against the cylinder. 

 The same thing was observed more sensibly in some stuffed quadrupeds that 

 hung in our apartments. Their furred skins, whether rubbed or not, often 

 accumulated such a charge of the electrical fluid, that when the knuckles were 

 presented to them, they gave a smart shock which was felt as far as the 

 elbow. 



The Aurora did not often appear immediately after sun-set. It seemed 

 that the absence of that luminary, for some hours, was in general required for 

 the production of a state of atmosphere favourable to the generation of the 

 Aurora. On one occasion only (March 8th) did I observe it distinctly, pre- 

 vious to the disappearance of day-light. 



By the way of more perfectly describing one form of the Aurora, rather 

 than with the view of drawing any inference, I shall state that the slender 

 beams of light which compose the Aurora when its motions are rapid, are ex- 

 actly similar to what would be produced by a quick succession of electric 

 sparks, elicited from a charged cylinder, by a body studded with a row of points, 

 moved rapidly to and fro before it.— Or, supposing along range of cloud were 

 to commence at one end, to impart, from successive points of its surface, its 

 charge to a similar parallel mass, a current of light would be produced, appa- 

 rently consisting of parallel beams, lying at right angles to its line of direction, 

 as described on the night of the 29-30th December, at 2h. a.m. Were the clouds 

 supposed to lie in different planes, and to be bounded by curved edges, every 

 variety of form which that species of Aurora assumes might be produced. The 

 colour of the. light of the Aurora is not always noted in the following pages, but 

 when faint it was generally steel-grey, or that of the galaxy. When the low 

 hazy modification of cirro-stratus appeared in the sky, the light, for the most 

 part, was a gold-yellow colour, more or less deep ; and when the sky was clear, 

 or when only a few fine threads or thin shoots of cloud were visible, the colours 

 were vivid and prismatic. 



I have never heard any sound that could be unequivocally considered as 

 originating in the Aurora ; but the uniform testimony of the natives, both Crees 

 Copper Indians, and Esquimaux, and of all the older residents in the country', 

 induce me to believe that its motions are sometimes audible. These instances 

 are, however, rare, as will appear when I state that I have now had au 



