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THE HOUSATONIC VALLEY.
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into the limestone, as well as by the serrated contour of the ridge when seen from the northwest (cf. Fig. 3). Between Tom's Hill and Miles Hill is a fold of Egremont Limestone overturned to the west and enclosing a core of the Everett Schist. The islands of limestone inclosed in the schist of the eastern flank of Miles Hill, are the result of frequent alternations of pitch in small reversed folds which for a short distance have been ruptured. A stereogram showing the surface of the schist before it had been cut away by erosion would here present the characters of a choppy sea (cf. Fig. 2 E.) These long alternating belts of schist and limestone on the southeast foot of the hill northwest of the railroad bridge (V on map), are indicated topographically by a series of low, sharp ridges which have gradual east and steep west slopes (cf. Plate VII., Fig. 2). Farther south, near the railroad bridge, the several schist ridges become fused together and show more symmetrical undulations. The dips are here uniformly east at angles varying from 30° to 50°, and the closeness with which the belts are crowded together allows insufficient room for the full thickness of the Egremont limestone of this vicinity. The indications therefore are that the folds have here been so sharply compressed that the beds have found relief in a slight dislocation or thrust, producing a structure best illustrated in Fig. 2 (B), to which Suess has applied the term Schuppenstruktur,[1] and which I would term weather-board structure. It is probable that both the throw and displacement of these dislocations is very slight, being greatest where the crest-lines show an anticlinal structure and least where they show a synclinal structure. An attempt has been made to show the nature of these dislocations as they are supposed to occur on the southeast flank of Miles Hill (Fig. 2 E.) Owing to the convering of earth in the valleys, the course of the fault is not exposed. The only locality where the beginnings of such a

  1. ↑ Eduard Suess: Das Antlitz der Erde, Vol. I., p. 149.
    Gosselet has used structure ecailleuse (Ann. soc. geol. du Nord, Vol. XII., 1885, p. 197) for similar structures, and Margerie recommends structure imbriquée (Margerie et Heim, Les dislocations de l'ecorce terrestre, Zürich, 1888, p. 82).
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