VEINS IN GRANITIC ROCK. 567 
same colour and other characters; they are mere lines themselves, 
but the green colour extends an inch either side gradually losing 
itself in the dark colour of the syenite. Figure 5 is another instance 
of a large number of epidotic veins variously branching and occasion- 
ally intersecting ; it isa diminished sketch of a surface six feet square. 
Fig. 4. Fig. 5. 
The rock is granite, and is part of a granite vein. For half to three- 
quarters of an inch either side of the epidotic seam, the colour is red, 
as above explained. Instead of a single seam of epidote along the 
centre of one of the broadest of these bands, there are three or four 
very narrow lines running along together, and in one of them the 
epidote is partially crystallized. 
Additional remarks on the epidotic veins, will be offered after de- 
scribing the granitic veins. 
Granitic Veins.—The various cliffs and artificial excavations for 
roads, about Valparaiso, afford numerous sections for the display of 
granitic veins. In many places they traverse the rock apparently in 
all directions, reticulating the face of the cliffs, so that the size of the 
intervals between them seldom exceeds ten feet square. We might 
describe some of the cliffs as consisting of a network of granite veins 
filled in with gneissoid granite. 
The only minerals noticed in these veins besides epidote, are tour- 
maline, garnet, chlorite, and magnetic iron. ‘The tourmaline is in 
blue-black crystals, but they are seldom well defined. The garnets 
are small and occur in a few only of the veins. Chlorite covers por- 
tions of the walls in some places south of Valparaiso, not as a con- 
tinuous coating, but scattered here and there in pieces as thick as the 
hand, and a few inches broad. The mineral has the usual imperfectly 
crystalline texture and dark olive-green colour. Magnetic iron occu- 
pies the centre of narrow veins, intersecting the hornblendic schist 
and granite north of Vifia del Mar, and at other localities it is some- 
times disseminated in small quantities through the granite. Iron 
