VEINS IN GRANITIC ROCK. 571 
the last, follows the same direction. Another, one foot wide, runs from 
south-southeast to north-northwest. 
From these observations, it appears that the veins in this neighbour- 
hood vary in direction from south-southeast to southeast by east, or 
north-northwest to northwest by west. 
On the ridge back of Valparaiso, two miles west of the first Post 
House, there are numerous veins, and the general course is southeast 
by south and northwest by north, with a dip to the northwestward. 
Two other veins in the same region run in a northeast by east and 
southwest by west direction. Another has a south-southeast and. 
north-northwest course. 
The dip is very irregular; it is sometimes to the northeastward, 
and at others to the southwestward. The large vein along the coast, 
so often referred to, consists properly of two veins, crossing nearly at 
sixty degrees, and dipping in the two directions just stated. ‘The line 
of intersection is a few feet above high-water mark. 
Intersections.—The granite veins present some striking peculiarities 
at their intersections, and are also variously faulted. Figures 6, 7, 
8, illustrate the crossing of the two large veins on the coast. In 
figure 6 the two veins are so united and commingled at their intersec- 
tion, that it 1s impossible to say which one cuts the other. Indeed 
there is no actual intersection: the veins seem to combine in one, and 
then again to disjoin, and continue on their respective courses. Where 
united, the included ¢s/ets of gneiss are very numerous and extremely 
irregular in form: and the small veins which are subordinate to the 
larger run around in the most eccentric manner, sometimes following 
a zigzag course, as the figure shows. <A separate small vein may be 
seen coming up from the left and passing some distance into the veins 
at their junction, and then extending apparently into the upper right 
branch. 
In figure 7, a few rods distant from where figure 6 was sketched, 
the veins are each divided into two portions or strands, and they inter- 
sect. One of these strands, a, distinctly intersects one in the other 
vein, but is itself intersected by the other strand of the latter ; while 
the second strand of the former is intersected by both of the latter. 
These large veins occur on the surface of a cliff one hundred feet 
high, and the view includes about fifteen feet of the lower part. 
In the third figure, (figure 8,) both veins, as they approach the in- 
tersection, become gradually narrower, with a curving outline; and 
where they cross, they have less than one fourth their ordinary width. 
