Intelligence and Miscellaneous Articles". 235 



Cassiopeia, Ursa Minor, and the square of Ursa Major: it soon 

 reached the zenith and gradually disappeared. 



At half-past eleven the aurora again began to sink slowly, and 

 did not rise afterwards. At five minutes before twelve a large bril- 

 liant meteor, the only one observed through the night, passed under 

 Ursa Major. At one o'clock A.M. the highest part of the aurora 

 about the magnetic north had sunk to within six or seven degrees 

 of the horizon ; yet bright coruscations occasionally emanated from 

 it till two, when the observations were discontinued, as no more 

 interesting meteoric appearances were likely to occur. 



The vertex of each of the rainbow-like arches that were formed 

 by streamers from or near'the intersecting points of the aurora with 

 the horizon, coincided with the magnetic north within one or two 

 degrees, and uniformly preserved this parallelism in passing off 

 towards the south. 



During the evening and night, while the aurora was pretty high, 

 the light which it spread through the atmosphere was equal to the 

 light of the moon shining through a very attenuated cloud j and the 

 stars which formed the square and tail of Ursa Major were almost 

 imperceptible, inconsequence of the refulgence of the aurora. 



Of all the auroras boreales that have been observed here the 

 last twenty years (some say forty years), this was the most exten- 

 sive, the most beautiful in colours, and the most interesting, on ac- 

 count of the singular phaenomena which it displayed, in the number 

 of distinct luminous bows, which were presented in the course of 

 the night. This aurora borealis was seen at Paris and at Brussels. 



In two days and a half after the aurora a very strong gale of 

 wind came on from the north-east, and continued about twenty-four 

 hours. 



There were also faint auroras on the preceding and following 

 evenings ; and a luminous one, though not high, from six till nine 

 in the evening of the 1 1 th, which would have been interesting but 

 for the interposition of clouds throughout the night. 



A MODE OF ASCERTAINING THE VALUE OF MANGANESE ORES. 



Dr. Turner, Professor of Chemistry in the London University, has 

 given a method of ascertaining the commercial value of the ores of 

 manganese, in the last Number of the Royal Institution Journal, the 

 object being solely to ascertain the relative quantities of chlorine, 

 which an equal weight of each ore was capable of supplying. The 

 method of manipulating is as follows : About ten grains of the ore 

 in fine powder is introduced into a flask capable of containing about 

 an ounce of water, and into its neck is fitted by grinding a bent tube 

 about two inches long, which conducts the chlorine from the flask into 

 a tube about sixteen inches in length, and five-eighths of an inch wide, 

 full of water, and inverted in a small evaporating capsule, employed 

 as a pneumatic trough. The apparatus being adjusted, the flask is 

 half filled with concentrated muriatic acid, the conducting tube in- 

 stantly inserted, and heat applied by means of a spirit-lamp. The air 

 of the flask, together with the chlorine, is then collected, the greater 

 part of the latter, if the gas is not very rapidly disengaged, being ab- 



2 H 2 sorbed 



