SOURCE   OF   ST.   PETBK's  RIVER.                  205
sfe found upon it; whereas these were uniformly observed to the exclusion of the scales of hornstone upon the surface of the calcareous stratum that overlays the sandstone. If contrary to the opinion which we have been led to adopt, the limestone be supposed to constitute but one formation, whether above or below the sandstone; then will we ask, whence come these flattened fragments, observed upon the sandstone ? If from the remains of a more solid stratum in the limestone itself, why, let us again ask, are not these likewise observed upon the inferior limestone itself? Why is not the hornstone, which appears to characterize the lower limestone, also observed upon the sandstone ? We might further ask, if the limestone above and below the sandstone bed be the same, ought we not to find signs of calcareous beds subordinate to the sandstone, and would we not have a right to expect an interposition of limestone in the immense bed of sandstone which, a§ we have previously stated, is often one hundred feet in thickness ? Yet this we never observed to be the case.
If an alternation of sandstone and limestone strata belonging to the same formation were indicated by the characters previously alluded to, would we not be entitled to expect that the fragments and detritus of both should be found together ? Yet in the valleys of the sandstone country, and particularly in the beautiful and romantic one which rested upon the limestone, and was enclosed by sandstone hills, we observed no fragments of the former rock, and but a few large blocks of sandstone which had evidently fallen of late from the sides of the valley. While travelling on the hills we observed that they were covered, in certain parts, with a thin stratum of fine sand, resulting from a slight decomposition of the rock, as is observable in all sandstones of a loose texture.