pwr Mile i) Say, - bi ~ sae ; 
sa . E 
ae Me 7" . ¥ ei Fs 
* i ae rie 
sa Erratic Phenieuviie about Lake Superior. 
ie phenomena preceded the other; and again, if the same éatise . 
‘s acted in both cases, or if one of ‘the causes can be applied to one 
series of these phenomena, and the other cause to the other series. *: 
An investigation of the erratic phenomena in North America 
. Seems to me likely to settle this question, as the northern erratics ~ 
occur here in an undisturbed continuation over tracts of land far 
more extensive than those in which they have been observed in 
Europe. For my own part, I have already traced them from the 
eastern shores of Nova Scotia through New England and the © 
North Western States of North America and the Canadas as far’ - 
as the western extremity of Lake Superior, a region embracing .’ 
about thirty degrees of longitude. Here, as in Northern Europe, 
the beulders evidently originated farther north than their present 
+ location, and have been moved universally in a main direction 
from north to sout 
From data which are, however, rather incomplete, it can be 
further admitted that similar phenomena occur further west across 
whole continent, everywhere presenting the same relations. 
eae: "That j is to say, everywhere pointing to the north as to the region 
/ 3 of the boulders, which generally disappear about latitude 38°. 
Without entering at present into a full discussion of any theo- 
retical views of the subject, it is plain that any theory, to be sat- 
isfactory, should embrace both the extensive northern phenomena 
in Europe and North America, and settle the relation of these 
phenomena to the well- authenticated local phenomena of Central 
Wheth her America itself has its special we: circumscribed cen- 
tres of distribution or not, remains to be see It seems, how- 
ever, from a few facts observed in the White cntaite, that this 
chain, as well as the mountains of northeastern New York, has 
not been exclusively—and for the whole duration of the trans- 
portation of these materials—under the influence of the cause 
which has aistribated the erratics through such wide space over 
the continent of North America. But whether this be the case 
or not, (and I trust local investigations will soon settle the ques- 
tion, ) 'E maintain that the cause which has transported these 
boulders in the American continent must have acted simultane- 
ously over the whole ground which these boulders cover, as they 
sent throughout the continent an uninterrupted sheet of loose . 
materials, of the same general nature, connected in aa same gen- 
eral manner, and evidently or a at the same tim 
Northern America. So that the cause which transported them, 
whatever it may be, must have acted simultaneously — the 
whole tract of land west of the Ural Mountains, and east of the 
:ky Mountains, without assuming any thing a ee North- 
