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are corrugated by a tertiary system of small flexures, and examination of the plications at localities usually reveals even a quarternary system of minor foldings. Many of the small knolls near Salisbury present a surface something like the half of a muskmelon, except that a section, instead of resembling an epicycloid, would be more like a sine curve developed on an arc (cf. Fig. 2 (C). Figure 2 (D) illustrates this structure as seen in the anticlinal ridge No. 6 south of Twin Lakes Station, and in a number of small hills near Salisbury.

The Everett Schist occurs in caps or mantles which are for the most part shallow, nearly symmetrical, synclinals, as exhibited

Fig. 3.View of Tom's Hill from the northwest, showing the serrated contour caused by the alternation of belts of schist and limestone. A, Tom's Hill. B, Northeast foot of Miles Hill. C, Canaan Mt. D, Babe's Hill.

in Turnip Rock (9), the cap on the southwest slope of Peck's Hill (27), and the Washining Lake Mantle (5), the latter being a double synclinal, as shown by the anticlinal ridge which forms the island in the lake.

Structure of Tom's Hill.—The double-peaked elevation east of Washining Lake is a compound anticlinal of Riga Schist, with two prominent crests appearing in Tom's Hill and Miles Hill respectively. These anticlinals, like most others in this region, are pushed over to the westward. A number of subordinate anticlinals, likewise compressed and overturned and here probably ruptured, are indicated on the map along the northern boundary of the Riga Schist by fingers of schist which protrude