However, such a junction of veins sometimes disunites and in this
way it happens that the vein which was the right-hand vein becomes
the left; and again, the one which was on the left becomes the right.
way it happens that the vein which was the right-hand vein becomes
the left; and again, the one which was on the left becomes the right.
Furthermore, one vein may be split and divided into parts by some hard
rock resembling a beak, or stringers in soft rock may sunder the vein and
make two or more. These sometimes join together again and sometimes
remain divided.
rock resembling a beak, or stringers in soft rock may sunder the vein and
make two or more. These sometimes join together again and sometimes
remain divided.
A, B—VEINS DIVIDING. C—THE SAME JOINING.
Whether a vein is separating from or uniting with another can be
deter
mined only from the seams in the rocks. For example, if a principal
vein runs from the east to the west, the rock seams descend in depth
likewise from the east toward the west, and the associated vein which
joins with the principal vein, whether it runs from the south or the north,
has its rock seams extending in the same way as its own, and they do not
conform with the seams in the rock of the principal vein—which remain
the same after the junction—unless the associated vein proceeds in the same
direction as the principal vein. In that case we name the broader vein the
principal one, and the narrower the associated vein. But if the principal
vein splits, the rock seams which belong respectively to the parts, keep
the same course when descending in depth as those of the principal vein.
mined only from the seams in the rocks. For example, if a principal
vein runs from the east to the west, the rock seams descend in depth
likewise from the east toward the west, and the associated vein which
joins with the principal vein, whether it runs from the south or the north,
has its rock seams extending in the same way as its own, and they do not
conform with the seams in the rock of the principal vein—which remain
the same after the junction—unless the associated vein proceeds in the same
direction as the principal vein. In that case we name the broader vein the
principal one, and the narrower the associated vein. But if the principal
vein splits, the rock seams which belong respectively to the parts, keep
the same course when descending in depth as those of the principal vein.
But enough of venae profundae, their junctions and divisions.
Now
we come to venae dilatatae. A vena dilatata may either cross a vena profunda,
or join with it, or it may be cut by a vena profunda, and be divided into parts.
we come to venae dilatatae. A vena dilatata may either cross a vena profunda,
or join with it, or it may be cut by a vena profunda, and be divided into parts.