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STRUCTURE OF THE MOUNT WASHINGTON MASS.
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the mountain as composed of two close-pressed synclinals in the Mt. Washington plateau with steep easterly inclined axes, and that these synclinals are synclinals of slate riding over a single synclinal of limestone.

In 1877, in a paper entitled, "On the Relations of the Geology of Vermont to that of Berkshire,"[1] he adds, referring to the anticlinals of limestone between the three northern spurs of the mountain:

"It has not been possible to follow these subordinate anticlinals southward, because the limestone is not continued far in that direction and the summit of the mountain is under soil and cultivated farms. But yet the fact of flexure at the north end is strong reason for believing that similar flexures, if not the same continued, characterize the whole length from north to south of the mountain-mass, such a slate easily flexing under uplifting lateral pressure. This is further sustained by observations proving that other subordinate anticlinals exist on the western slope of the mountain, in the vicinity of Copake Furnace. Close to the western foot there are two nearly parallel limestone areas, parallel to the axis of the range. The inner (or more eastern) one is about a mile long, and the other about half a mile. They are separated from one another by a thin belt of hydromica slate, and the same slate exists on the other sides. The dip of the beds of limestone and slate is to the eastward 50°, the strike averaging N. 15° E. (true). They are evidently registers of local folds—anticlinal and synclinal, the former bringing up the limestone."

In the paper "On the Hudson River age of the Taconic Schists,"[2] Professor Dana has put on record new observations showing the synclinal character of the mountain (l. c., p. 376) and printed a map including a part of Mt. Washington (p. 379)[3].

Another paper, "On the Southward Ending of a Great Synclinal in the Taconic Range,"[4] is specially devoted to a consideration of the structure of Mt. Washington, and contains a map of the southern portion of the mountain on a scale of eight-tenths of an inch to the mile. Professor Dana's earlier conclusions as to the synclinal character of the mountain, had been largely drawn from observations made in Massachusetts. The conclusion that the synclinal character of the northern portion of the mountain is continued to the southern extremity, he drew from the fact

  1. ↑ Am. Jour. Sci., 3rd ser., vol. xiv., pp. 262-263.
  2. ↑ Am. Jour. Sci., 3d ser., vol. xvii., pp. 375-378 (May, 1879).
  3. ↑ (Cf. also ibidem, Supplement to vol. 18, for dip and strike observations).
  4. ↑ Ibidem, vol. xxviii., p. 268 (Oct., 1884).
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