258 
SECOND REPORT - 1832 . 
netic intensity*. In America also, experiments have led to the 
same result 
On the occasion of the great aurora of the 7th January 1831, 
M. Arago observed the magnetic needle powerfully affected, 
whilst Mr. Sturgeon of Woolwich could not notice it at all %: 
on the 19th April 1831, Mr. Christie of Woolwich, in com¬ 
pany with Mr. Faraday, observed the most unequivocal signs 
of auroral action §. This observation, made by two philosophers 
perfectly habituated to such experiments, must be considered 
probably the most complete evidence yet obtained in this coun¬ 
try. On the whole it seems undeniable that the aurora borealis, 
frequently at least, exercises the most marked action on the 
magnetic needle, with regard to variation, dip, and intensity. 
The circumstances under which it does not take place, require 
however the most careful scrutiny, and we hope that Mr. Far- 
quharson will pursue unremittingly his observations. Unfa¬ 
vourable as is the sky of Britain for many kinds of experiment, 
her geographical position is in other respects highly important 
as concerns scientific undertakings. Among these especially 
rank Meteorology and Magnetism; and it were deeply to be 
desired that she should lead the way in the prosecution of these 
too much neglected sciences. There can be no reason why ex¬ 
periments should not be as well conducted here as in the cabi¬ 
net of M. Arago ; and when Baron Humboldt boasted to the 
French Academy of the wide distribution of his “ maisons mag- 
netiques,” or magnetic observatories, from Paris, the centre of 
civilization, to the wilds of Siberia, and to Pekin itself, whose 
gates have been so long shut against the approaches of science, 
—it is a humiliating fact that he could not with truth have men¬ 
tioned Britain as possessing a solitary establishment of this 
description, either within her own limits, or probably even in 
the range of her much more widely extended dependencies. 
It may not be superfluous to add in conclusion, should more 
errors (especially those of omission,) be found in the preceding 
Report than might seem to be inseparable from the nature of 
the work,-—that it has been drawn up within a very limited space 
of time, and under the pressure of a variety of preparations for 
an extended scientific tour on the Continent. 
June, 1832. 
* Communicated to the Academy at Paris by Baron Humboldt, 10th Oct. 1831. 
p Sillimaii s Journal, 1828. 
X Philosophical Magazine , N.S. ix. 151. 
§ Journal of the Royal Institution, Dec. 1831, p. 271. 
