410 Proceedings of the Royal Physical Society. 
netic force of the Old World (the weaker of the two), lies 
a good many degrees farther north than that of the New 
World. 
Another fact, which is rather a puzzling one, is the very 
great relative proportion of metallic falls which have been 
discovered in America, as compared with any other part of the 
known world — thirty-two meteoric irons having been found 
in the United States, according to Professor Shepard, twenty- 
three of which are included in his meteoric zone. While 
only fourteen meteoric irons (whose time of fall is unknown) 
have been recorded as found in the Old World, and eleven of 
these falls are included in its so-called meteoric zone.* Mr 
Greg gives the number of localities of meteoric irons in the 
Western Hemisphere as fifty-seven ; those of the Eastern 
Hemisphere being twenty-seven. f Various explanations have 
been given of these facts ; it is rather curious, however, 
to observe, that in the New World, we have the greatest 
number of metallic falls, apparently in the neighbourhood of 
the very locality where the magnetic force is described as 
being in a maximum in the northern hemisphere. The 
metallic falls of the Old World seem also to bear a rela- 
tion to the other northern magnetic pole ; though, from its 
force of attraction being relatively weaker, it may be, the 
number of these metallic aerolites here is less, and the con- 
centration of them together would also appear to be less ; the 
meteorites straggling, in their deposition, to greater distances 
from its centre, and so adding to the apparent length of this 
so-called meteoric zone. Can these various circumstances be 
dependent simply on an accidental coincidence'? or do they 
not, at least at first sight, suggest the idea that this strange 
agent of magnetism has really something to do with these 
peculiar arrangements 1 
Writers on terrestrial magnetism tell us, as one of the 
ascertained results of their labours, that the agents of the 
greater part of the magnetic force of the earth are situated 
exclusively in the interior of the earth, although minor mag- 
netic oscillations and influences on its surface are due, without 
doubt, to the direct magnetic influence of the sun and moon ; 
* American Journal of Science, 1850. t Essay on Meteorites, 1855. 
