228 SURFACE GEOLOGY. 



At the east line of Gilead, on the north side, the striae run S. 60° E. No 

 further marks were seen on the north side of the river from this point to 

 Bethel hill. Ledges are scarce, and covered by drift. 



The observations mentioned above, between Peaked hill and Gilead, 

 on the south side of the river, are taken from Prof. Vose's account of 

 this interesting glacier.* I will quote his own words for the facts be- 

 tween Peaked hill and Bethel. His course was up the valley from Bethel. 



Where glacial furrows are found upon the tops of the Bethel hills, they run nearly- 

 north and south. Proceeding up the valley towards Gorham upon the south bank, at 

 a point about two and a half miles above Bethel, before we really enter the close valley, 

 and perhaps one hundred feet above the river, a small exposure of rock is seen directly 

 in the common road, being about six feet square, with a long, gently sloping polished 

 surface towards the north, and a steep and rough face towards the south. The furrows 

 upon the smooth northern surface run north and south ; and the hills, upon the sum- 

 mits of which the furrows run north and south, lie exactly north of this rock upon the 

 opposite side of the river. This furrowing had evidently no connection with the An- 

 droscoggin, as the grooves point almost directly across it. Continuing up the valley 

 just above Pleasant river, five miles above Bethel, about a quarter of a mile south of 

 the road and perhaps two hundred feet above the river, the rocks are well polished ; 

 and, from faint lines upon masses of quartz, the direction of the ice is seen to have 

 been S. 50° E. Six miles above Bethel, where the river, railway, and road draw closely 

 together and sweep around the base of Peaked hill, there is a steep ledge, about twenty 

 feet high, close to the track, which is polished and furrowed, both upon the nearly ver- 

 tical face towards the river, and also upon a narrow horizontal shelf part way up on the 

 ledge. The lines upon the horizontal shelf run S. 20° E., the vertical face standing S. 

 230-30° E. It is necessary, however, to be guarded in drawing conclusions from gla- 

 cial traces left upon vertical or steeply inclined surfaces, as the movement of ice, jam- 

 ming through a narrow passage, may be locally disturbed, so as to give a direction to 

 the furrows quite different from that of the general movement of the glacier. This was 

 most likely the case at the point referred to, as the furrows on the opposite side of 

 the hill — i. e., the south side — ran S. 80° E., thus according much more nearly with 

 the traces, both above and below this point, than the furrows upon the steep face tow- 

 ards the river do. The ice would seem to have jiassed around both sides of this hill ; 

 and we can readily conceive that this might be, since the depression in the rear, south 

 of the elevation, is quite low. Indeed, in the fine view from Sunset Rock in Bethel, 

 Peaked hill seems to rise in a very isolated manner from the middle of the valley, which 

 makes it a very prominent feature in that magnificent picture. 



* American Naturalist , vol. ii, p. 284. 



