7492. antiquities in Scotland. 129 
All the walls of this kind that I have yet seen or 
heard of, have been evidently erected as places of 
défence. They, for the most part, surround a small 
area on the top of some steep conical hill, of very 
difficult accefs. It often happens that there is easier 
accefs to the top of one of these hills at one place 
than at any other ; and there they have always had the 
entry into the fort, which has always been defended 
_ by outworks, more or lefs strong, according to the 
degree of declivity at that place. If the form of the 
_ hill admitted of accefs only at one place, there are 
outworks only at one place; but if there are more 
places of easy accefs, the outworks are opposed to 
each of them, and they are proportioned in extent te 
the nature of the ground. 
| The first fortification of this kind, that I’saw, was 
upon the top of a steep hill called Knock-ferrel, two 
miles west from Dingwall in Rofsfhire. And as an 
idea of all the others may be formed from this one, 
I thall here subjoin a particular description of it. 
The hill is of a longifh form, rising into a ridge at 
top, long in proportion to its breadth. It is of great 
height, and extremely steep on both sides ; so that 
‘when it is viewed at a distance from either end, it 
appears of a conical fhape, very perfect and beautiful 
po look at ; but, when viewed from one side, one of 
‘the ends is seen to be much steeper than the other. 
The narrow declivity of the hill is of easy accefs, 
and forms a natural road by which you may ascend 
‘to the top on horseback ; and at this end has been the 
entry into the fort A. (see plan.) This fort’consists, as 
J guefsed by my eye, of a long eliptical area of near 
