CAUSE OF DISTURBANCES, GtC. 
631 
from Tennessee through Georgia, the Carolinas, Virginia, Maryland, Pennsylvania, New- 
Jersey, New-York, Connecticut, Massachusetts, Vermont, New-Hampshire, and so on to 
Canada, and producing the transverse strata, and some of the echelon movements and lateral 
displacements that have been alluded to in various places in this volume, intruding granite 
among preexisting rocks, and modifying them greatly in character. There is already suffi¬ 
cient known on this subject to render it an interesting one for discussion, but this volume is 
already swelled to an unreasonable size, and the above paragraphs contain the deductions 
from the facts. 
4. Cause op disturbances and changes of characters. 
The elevation of rocks to an inclined position, different from that in which they were 
formed; the elevation of islands and continents above the level of the sea, below which they 
were once buried; the contortions, wrinkling, and folding of strata, and the elevation of 
mountain chains in former times; and the grrdual changes of level with reference to the sea 
which are now in progress on parts of the earth’s surface, have been referred to various 
causes, such as, 1st. An upheaving force, from the formation of steam and other elastic 
vapors in a high state of tension; 2d. The contraction of the earth by secular refrigeration, 
and the plications and foldings necessarily resulting from the solidified exterior collapsing 
upon the contracted nucleus by diminished temperature; 3d. The undulatory action of the 
fluid interior, combined with a tangential force. 
These causes may all be true, and are perhaps sufficient to account for the facts. I may, 
however, be pardoned for suggesting an additional cause for the lateral tangential force, in 
connection with that arising from collapse of the exterior. 
It is well known that the folded, crumpled, wrinkled, and inverted rocks of western 
Massachusetts and eastern New-York, extend from Canada on the north, through Vermont, 
New-York, Massachusetts, New-Jersey, Pennsylvania, Maryland, Virginia and Carolina, 
into Tennessee, and how much farther on this continent or on others, we are not certain; 
but the continuation of this on a great circle of the earth, would pass through some other 
systems of elevation. Leaving these out of consideration, it is evident that the cause that 
has simultaneously acted over the country from Canada to Tennessee, and that has acted 
repeatedly along the same line, producing the same effects, raising the strata into undulations, 
crumpling them, and finally pitching them all over in “ folded axes,” so as to give to all an 
easterly dip in the more easterly ranges, must have been a general one.* The rocks seem to 
have been slidden laterally, wrinkled up, and folded over and crushed together, as described 
in various places in this volume when treating of the Champlain division, Taconic rocks, etc.; 
* Professor Hitchcock has given many developments on this subject (Vide Geological Report of Massachusetts, 1841, pp. 
474, 478, 574, 575) ; and Professors H D. and W. B. Rodgers, of Pennsylvania and Virginia, in their geological reports and 
naemoirs. I have not their works at hand, and do not, therefore, here give references to them. The discussions on this subject 
in New-York may be seen on page 381. 
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