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THE JOURNAL OF GEOLOGY.

the localities examined by him; in a general way the structure is that of an overturned series of folds, of an extremely complicated nature. These sections were made particularly to illustrate the structure of Hoosac Mountain, and the structure suggested in 1847 finds its verification in 1889[1] in Massachusetts, as far as the overturning of the anticline to the west is concerned. At that time little reference was made to the age of the rocks exposed along the axis, but they were mentioned as probably older than the Lower Silurian, while their relation to the younger rocks was not considered.

Zodack Thompson, in 1856, in considering the "Taconic System," makes reference to the structure of the rocks along the Green Mountain range[2].

He remarks that "one of the most marked peculiarities in the geology of Vermont is found in the general dip of the stratified rocks, which is, with a few trifling exceptions, toward a synclinal axis extending north and south near the center of the Green Mountain range." He notes a general westerly dip on the east side of the range, and an easterly dip on the west side. However, the question as to whether the Green Mountain rocks are really primary or post-Taconic was with him still in doubt, but he states that the weight of the evidence points towards the latter view, or more recent age.

In 1868, T. Sterry Hunt, after a study of the literature, while discussing Vermont geology, comes to much the same conclusion as Thomson.[3] To use his own words: "All the evidence, palæontological and stratigraphical, as yet brought forward, affords no proof of the existence in Vermont of any strata (a small spur of the Laurentian excepted) lower than the Potsdam

  1. ↑ See part 3, "Geology of the Green Mountains in Massachusetts," by R. Pumpelly, J. E. Wolff, T. Nelson Dale, and Bayard T. Putnam.Monograph U. S. Geol. Survey.Submitted in 1889.Not yet issued.
  2. ↑ Preliminary Report on the Natural History of the State of Vermont.Augustus Young.1856.Extract from Zodack Thompson's address on the Natural History of Vermont.App. 6, p. 67.
  3. ↑ On some points in the geology of Vermont, T. Sterry Hunt, Am. Jour. Sci., 2d series, Vol. XLVI., 1868, p. 229.
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