238 NOTICES OF THE MEETINGS [Jan. 21, 
Lamont (Dec. 1851) * was induced by recent researches in 
atmospheric magnetism, to examine the daily magnetic variation in 
declination, and found that, as a whole, it increased and diminished, 
and then increased again, having a regular variation of about ten 
years: the year 1844 was given as having a minimum variation of 
6’.61 and the year 1848 as presenting a maximum variation of 
11°.15. 
Sasinet (March, 1852) in searching for periodical laws amongst the 
mean effects of the Jarger magnetic disturbances, found a simultaneous 
period of increase and decrease both at Hobarton and Toronto, on 
opposite sides of the globe ; the minimum effect was in 1843, and the 
maximum effect in 1848, according therefore almost exactly with 
Lamont’s observations at Munich. But, besides that, he pointed 
out the extraordinary circumstance that this similar variation of the 
daily magnetic declination is the same in length of period as that 
discovered by M. Schwabe for the solar spots ; and still more, that 
the maxima and minima of these two most different phenomena 
coincide; for 1843 presents the least diurnal variation and the 
smallest number of solar spots, and 1848 the largest magnetic 
variation and the greatest number of solar obscurations. He has 
also observed that the same period of increase and decrease exists 
with the same epochs in the diurnal variation of the magnetic 
inclination of the earth’s magnetic force in both hemispheres. The 
phenomenon is general both as regards all the magnetic ele- 
ments, and in parts of the globe most distant from each other. 
Gautier appears to have been struck with the same coincidence ; 
but did not publish his idea until July 1852.{ Wotr of Berne, who 
has sought far into the history of the sun spots, had the same 
thought, publishing it first at the end of July or beginning of 
August, 1852.§ He endeavours to trace the general condition of 
the spots from the year 1600, and concludes that the true length of 
the period is 11.11 years. As it is impossible to conceive such a 
coincidence in the length of the period and the time of the maxima 
and minima of these two greatly differing phenomena, without 
believing in some relation of them to a common cause; so, the 
observation of such a coincidence at this moment ought to urge us 
more than ever into an earnest and vigorous investigation of the 
true and intimate nature of magnetism ; by means of which we now 
have hopes of touching in a new direction, not merely this remark- 
able force of the earth, but even the like powers of the sun itself. 
[M. F.] 
* Poggendorff, Annalen, LXXXIV. p. 572. 
+ Philosophical Transactions, 1852, page 103. 
t Bibliothéque Universelle, 1852, XX. 189. 
§ Proceedings of Natural Society of Berne, Nos. 245—247. 
