202 STRATIGRAPHICAL GEOLOGY. 



hornblendic gneiss, with nodules of epidote and veins of calcite. The 

 dip is a few degrees west of north, generally at 50° or more, so that it 

 evidently rests unconformably on the gneiss that follows, extensive out- 

 crops of which are found near Milan station. The dip of this is usually 

 north, or a few degrees west of north, near its western limit, but on its 

 eastern limit, where it varies from north, it is easterly.* 



On the steep, precipitous slope that overlooks Dead River pond, in a 

 rock itself apparently intrusive, there are dykes of a compact, jaspery- 

 looking rock, which is a compact feldspar; and in this there is a cave of 

 some little note. 



Going down the line of the railway, we find that it cuts a coarse gran- 

 ite that has plates of black mica three or four inches across, and this 

 immense mass has disturbed the hornblende gneiss in its immediate 

 vicinity ; but the position, general dip, and lithological character of this 

 gneiss are such that it is evidently a repetition of that in Milan, and it is 

 on the opposite side of the common gneiss. South of the station, at 

 Berlin falls, we have gneiss in several nearly vertical folds, and this is 

 traversed by immense "trap" dykes. It is difficult to determine as to 

 the stratigraphical position of this area. It seems to belong rather to 

 the remnant of an older formation, than to the rocks in either of the 

 areas we have described. 



At Gorham we have the rocks of the Montalban or White Mountain 

 series, dark gray gneisses with large plates of mica, having interstratified 

 with it the granitic gneiss so common in this series. The rocks here, as 

 well as elsewhere along their western border, have a westerly dip. The 

 interstratification of the hard gneisses that form so large a part of this 

 series is better shown here, probably, than anywhere in the whole area 

 they occupy in New Hampshire and Maine. A short distance above 

 Shelburne station is the only point where the railway cuts these rocks, 



* The facts, stated by Mr. Huntington upon pages 67 and 68, indicate the presence of an anticlinal axis in this 

 area of Lake gneiss. The Montalban rocks occupy a considerable tract in Dummer and Odell (p. 66), on the 

 north side of their axis, and the same rocks are spoken of further on along the Grand Trunk Railway. The Lake 

 gneiss area terminates a few miles north-east from Milan, the farthest exposures of it dipping northerly. These 

 observations are of importance in determining the relative positions of the Lake and Montalban divisions of the 

 Atlantic system. It will be noticed that these conclusions do not agree with the statement of J. P. Lesley (p. 194), 

 to the effect that the fundamental structure is synclinal. As Lesley does not give details, it may be that his syn- 

 clinal lies entirely to the south-east of Milan, where the structure is of that character. The range of this older 

 gneiss lies several miles to the north-west of the line of principal White Mountain elevation. Section XI, Plate 

 VI, Fig. 5, illustrates a part of this route along the railway. C. H. H. 



