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Hingliani Station, the inclaphyr outcrops prominently, forming 

 the summit and abrupt southern slope of a hill which is flanked 

 hy modified drift on the north. It is essentially similar in 

 character to the melaphyr east of the railroad, except that a 

 larger proportion of the rock is compact or not distinctly 

 amygdaloidal, some of the exposures resembling a massive slate. 

 Irregular segregations of epidote, etc., are common; and, as 

 already stated, the melaphyr encloses at one point a broken or 

 faulted layer a few inches in thickness of a beautifully laminated 

 or banded slate. This is well exposed at the present time in 

 tlie part of the ledge nearest to the station, where a new street 

 is being graded up the hill from West Street. So far as can be 

 determined, it is near the middle of the bed of melaphyr ; and it 

 is certainly far from any large body of slate. The most natural 

 explanation appears to be that it is a thin layer of tuff", similar 

 to some of the tuff beds of Nautasket, and hence another 

 indication that the bed of melaphyr is composite, consisting of 

 two or more ffows. The mela[)hyr is exposed along the strike 

 (W. byN.) in frequent ledges for about 1,000 feet, or to 

 within 500 feet of Hockley Lane, and is of similar character 

 throughout. 



On the north side of the first hill, in the angle between the 

 melaphyr and West Street, are several outcrops of conglomerate ; 

 but tiie contact is not exposed here. North and west from this 

 point tiie stratified rocks are almost entirely concealed by the 

 undulating modified drift. I have recently discovered, how- 

 ever, that the small ledges of melaphyr on the west slope of the 

 main hill, lying between the two large groups of ledges and 

 divided by the east-west fence, as shown on the map, are 

 bordered on the north side by fine conglomerate and sandstone 

 precisely similar to the rocks in contact with the melaphyr east 

 of the railroad ; and the contact, which is clearly exposed, is of 

 the same character. It is very evident that the sedimentary 

 rocks were deposited over the melaphyr, for they fill cracks in 

 it and are partly made up of debris derived from it. Near the 



