82 
along the shore as far as dike 27, when it also disappears, and 
the second conglomerate becomes the prevailing rock on the 
west side of the hill. This conglomerate, which is largely a 
fine-grained grit and sandstone, and hence plainly stratified, is 
characterized by segregations of red jasper, but in a less degree 
than the basal conglomerate. The dips are rather high, E. 
about 20? on the west side of the hill and S. E. 27? near the 
overlying porphyrite at the north base of the hill. The con- 
glomerate is conformably overlain by the great mass of porphy- 
rite which forms the summit and eastern and southern slopes of 
the hill, the actual contaet being particularly well-exposed on 
the north side. As a whole this porphyrite is similar to that of 
the Coastal area, but it is rather more felsitic in texture, redder 
in color, non-epidotic ; and segregations of red jasper occur in 
it to a limited extent. The base of the flow is mainly of a 
greenish gray color changing upward to a dull reddish tint ; and 
the upper part is largely of a deep dull red, often resembling at 
a little distance a dark red sandstone. Near the contaet with 
the underlying conglomerate it shows a distinct flow-structure, 
parallel with the contact, as well as a coarse and fine breceia- 
tion, the latter resembling or passing into a genuine **toad- 
stone" or spherulitic structure. Dike 27, which crosses the hill 
approximately at right angles to the strike, is accompanied by 
an important fault. It downthrows to the north and shifts the 
contact of the conglomerate and porphyrite about 175 feet, as 
shown on the map, equivalent to a vertical slip of fully 50 feet. 
This hill is a complex of dikes, and since all, apparently, are 
attended by some displacement, the continuity of the contact 
between the conglomerate and porphyrite is lost. This confu- 
sion makes it difficult, also, to determine the exact thickness of 
both the porphyrite and conglomerate. It is quite certain, 
however, that the entire thickness of the porphyrite, as well as 
of the conglomerate, is exposed here; for it is undoubtedly 
overlain conformably by the small patches of conglomerate on 
the southeast corner of the hill (Fig. 10). 
