EXCURSION III. 87 



bits of qtiartz. There are also beds of conglomerate ; and 

 the strata lean toward the slate, but less " end on ; " the dip 

 being about north 40 west. 



We are now approaching the junction of the old red sand- 

 stone with the slate ; but as this is not well seen in the bed 

 of the main stream, it will be more instructive to diverge to 

 the left, up the course of the west branch, as far as the dark 

 brow of slate, where the hill suddenly rises. Passing up the 

 bed of this west burn, we find the common red rock and 

 conglomerate succeeded by flinty or quartzose sandstone, 

 obviously metamorpbic. The cause of this change is soon 

 discovered. At a waterfall on the burn there is an outburst 

 of a peculiar granite amid the sandstone strata. This is an 

 intimate mixture of quartz and felspar, without mica; in fact, 

 the Eurite or Weiss-stein of mineralogists. It extends for 

 many yards in the bed and banks how far cannot be deter- 

 mined. Between it and the rocky brow which is formed of the 

 common dark slate, there are various metamorphic beds, con- 

 ducting us by insensible gradations into the true slate. 

 Some of these are white and gray flinty slates, others fine- 

 grained, hard sandstones. It is thus difficult to decide to 

 which series the beds ought to be referred. The strata have 

 been assimilated by the metamorphic action to which both 

 series have been alike subjected. A similar case occurs at 

 the junction on the White Water, to be noticed on another 

 Excursion. 



Returning now to the bed of the main stream, and entering 

 it some way above the waterfall at which we turned off, we 

 find similar white and gray quartzites about fifty yards in 

 front of a deep chasm, with a waterfall, cut out of the slate 

 rock. The sandstone is not seen in close proximity; but the 

 junction must be near, as this is the first point at which the 

 slate appears in the bed or banks. Two dikes of greenstone, 

 from opposite sides of the pool, unite at the edge of the fall, 

 twice bifurcate, and twice unite again, enclosing two long 

 elliptic masses of altered slate, and then continue as one dike 



