528 PHYSICAL GEOGRAPHY. 



wrote in 1706, records his remembrance of the time when the meteor was an object of 

 terror in his native island. It deserves remark, that its more frequent occurrence in the 

 Atlantic regions has been accompanied by its diminution in the eastern parts of Asia, as 

 Baron Yon Wrangel was assured by the natives there, who added that formerly it was 

 brighter than at present, and frequently coloured like the rainbow. A work by M. de Mairan, 

 entitled, Traite Physique et Historique de VAurore Boreale, published in 1754, records 

 all the observations of aurora from the sixth century down to that date, as far as they 

 appear upon the page of history. From this work, the singular view of an auroral 

 appearance now given is copied, which was observed for a few minutes at Breuillepont, 

 in Normandy, on the 19th of October, 1726. The gross number of distinct phenomena 

 enumerated by M. Mairan, amounts to 1441, distributed as follows : 



Number observed. 



From A. D. 583 to A. D. 1354 - 26 



1354 1560 - 34 



1560 1592 - 69 



1592 1633 - -70 



1633 1684 - - 34 



1684 1721 - - 219 



1721 1745 - 961 



1745 1751 - 28 



Of course, during the earlier periods, we must suppose that a great many instances 

 occurred which found no record ; but the high numbers which appear after the close of 

 the seventeenth century, may be considered as confirming the presumption of auroral 

 exhibitions having become more common in European localities. Distributed according 

 to the different months in which the aurora appeared, the numbers to be assigned to each 

 are 



January - - - 1 1 3 



February - - - - 141 



March - - - - 202 



April 124 



May 45 



June ----- 22 



July - - - - - ! - 22 

 August 84 



September- - - i ,- - 172 

 October - -.':'- 212 



November 153 



December - - - - -151 



The instances in the winter half-year amount to 972, and those in the summer to 469, 

 being nearly in the proportion of 2 to 1 in favour of the former. 



It has been repeatedly affirmed, that auroral displays are attended with sound, variously 

 described as a hissing, murmuring, and crackling noise. Blagden and Gmelin offer 

 several testimonies of a rustling noise having been occasionally heard ; Nairne, Cavallo, 

 and others speak of a hissing sound ; and Henderson remarks, that in Iceland, when 

 the coruscations are particularly quick and vivid, a crackling noise is heard, resembling 

 that which attends the escape of the sparks from an electric machine. Captain Lyon 

 observes, that the sudden glare and rapid bursts of those wondrous showers of fire that 

 appear in the sky make it difficult to fancy their movements wholly without sound, but 

 nothing was ever heard by him, or by his companion Captain Parry. The latter states, 

 that it was too cold to admit of the ears being long uncovered ; but Lyon declares, that he 

 stood for hours on the ice listening, and at a distance from every sounding body, without 

 catching the faintest noise. But the counter testimonies are so numerous, that this point 

 must be deemed at present an open question. Dr. Richardson was an attentive student of 

 the aurora during the arctic land expedition of Captain Franklin ; and though he never 

 heard any sound that could be unequivocally considered as originating with the meteor, 

 yet the united testimony of the natives, both Crees, Copper Indians, and Esquimaux, and 



