. Annual report of the Regents. New York State Museum; Science. 476 NEW YORK STATE MUSEUM Confirmatory though not conclusive evidence in the same direc- tion is found a few rods north of the locality described where there are several patches of impure limestone ranging from a few feet up to some rods in diameter, which are also with much probability intrusions in the syenite, though as is commonly the case with limestones the contacts are so hidden as to make it impossible to determine the relations with certainty. Similar phenomena are shown along the low ridge extending westward from near th
. Annual report of the Regents. New York State Museum; Science. 476 NEW YORK STATE MUSEUM Confirmatory though not conclusive evidence in the same direc- tion is found a few rods north of the locality described where there are several patches of impure limestone ranging from a few feet up to some rods in diameter, which are also with much probability intrusions in the syenite, though as is commonly the case with limestones the contacts are so hidden as to make it impossible to determine the relations with certainty. Similar phenomena are shown along the low ridge extending westward from near the railroad station in Harrisville. The ridge is formed by the syenite standing up above the more easily eroded limestone of the valley, and the two formations may be seen along the line of contact. This line is, for a supposedly in- trusive contact surprisingly straight, suggesting rather at first sight the contact between conformable formations, or perhaps a fault line. But when traced in detail many features appear that can be explained only as the phenomena of an intrusive contact. A few rods south of the station the syenite appears to send tongues into a fine grained gneiss of the limestone series, but the outcrops are poor and the evidence indecisive. About one eighth mile west the syenite forms a slightly sinu- ous contact with the limestone and with a peculiar gneiss, hav- ing the appearance of a contact zone. At the same time the syenite changes slightly, becoming nearly white and finer grained. The structure at this point is represented diagrammatically by fig. 1, the section shown being rather less than a rod wm mm ^m Gneiss Limestone Syenite Fig. 1 Contact of syenite with limestone series. Length of section about one rod. The meaning of the section is however apparent only when the fact is remembered that the structure would be quite different in other sections a short distance away along the strike. The sye- nite would be found cutting a different horizon o
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