On the sound whidi accompanies the Aurora Borealis. 75 



" The whole northern part of the horizon was covered with 

 a thin transparent luminous cloud, which emitted almost as 

 much light as the moon when three days old. This lumi- 

 nous cloud sometimes appeared settled, and totally free from 

 all manner of motion or agitation. At other times the agita- 

 tion was extremely great, and the coruscations or streams of 

 light which were perpendicular to the horizon, flew with the 

 utmost rapidity from east to west, and from west to east. One 

 of these coruscations, which appeared in the north-west, was 

 about 13 degrees long, and i a degree broad. Its western 

 edge was tinged with red and violet, and its brilliancy was al- 

 most equal to that of the moon in her first quarter, when the 

 sun is a few degrees below the horizon. *** During this 

 evening a whizzing- noise was heard in the air, exactly similar 

 to the sound which accompanies the passage of the elective 

 spark from the glass cylinder to the conductor ; and I was 

 informed by a friend, that during the time that the comsca- 

 tions were most vivid, the top of St Giles' 1 steeple seemed to 

 emit rays of light in every respect similar to a Leyden jar 

 when surcharged with the electric JluiA^ * 



Since these facts were published, Professor Hansteen has 

 added the following very important information on the subject. 



The first is an extract of a letter from M. Ramm, Royal 

 Inspector of Forests at Torset, to Professor Hansteen : 



" On reading Scoreby's voyage for the re-discovery of the 

 east coast of Greenland, I was surprised to observe, that nei- 

 ther he nor any body else had noticed the noise attend- 

 ing the motions of the Northern Lights. I believe, however, 

 that I have heard it repeatedly during a space of several 

 hours, when a boy of ten or eleven years old ; (it was in the 

 year 1766, 1767, or 176S.) I was then crossing, in winter, a 

 meadow, near which there was no forest, and I saw, for the 

 first time, the sky over me glowing with the most brilliant 

 light, playing in beautiful colours, in a manner I have never 

 seen since. The colours showed themselves very distinctly on 

 the plain, which was covered with snow or hoar frost, and / 



" We are informed by the Rev. Mr Grant of Cross and Bumess, Ork- 

 ney, that he has repeatedly heard the whizzing noise during the corusca- 

 tions of the Aurora Borealis. — Ed. 



