its continuation towards Falkirk, that Gordon wrote when he
said, that for nearly three miles " the wall is to be seen in
its greatest and highest perfection."1 The remark, happily,
still holds true.
The road from Bonnybridge over Bonnymuir, after crossing a
railway bridge, intersects the vallum south of Bonnyside house,
and a few yards north of Elfhill. Here the vallum enters
woodland, in which it continues for about 2 miles; and it is to
the absence of any disturbance by agriculture that its admirable
preservation is due.
Bonnyside.—Section No. 1. PLATE IV.
[Section of vallum, fosse, and outer mound.']
The military way appears to have gone round the south side
of Elfhill, while the vallum passed along on the north side.
The former is easily traceable in the little woodland enclosure
in which Elfhill sits, on the opposite side of the Bonnybridge
road from that on which section Bonnyside No. 1 is situated.
That section is 15 yards east of the stone wall bounding
the road from Bonnybridge at Bonnyside house, where the
vallum is intersected by that road. The ground slopes slowly
down from the military way to the vallum, beyond which the
falling slope continues. The vallum at this section stands 3 feet
6 inches in height above base. The kerbs of the base are of
squared freestone, and the bottoming of rough stone is of what
we have learnt to regard as normal character. The base breadth
from face of kerb to face of kerb is 15 feet. The soil of the
vallum is of whitish sand, but the black lines are here so
pronounced as to form a prominent and considerable portion of
the soil. This, indeed, is the case in all the Bonnyside sections.
There are no signs of the whitish clayey substance in this
cutting, and there are a few small stones. The largest stone—
an exceptionally large one—is 4 inches by 3. The layering
is here too palpable to escape the eye of the most casual visitor.
The black lines almost deserve to be called streaks. Ten of
them, distinct and continuous, and generally thick, travel in
1 Bin. Sept., p. 57.