On walking round the entrenchment at the bottom of the fosse, and keeping an eye upon the herbage--the best of all guides--one spot may be noticed where there grows a little of that `rowetty' grass seen in the damp furrows of the meadows. But there is no sign whatever of a basin or excavation to catch and contain this slight moisture--slight indeed, for the earth is as hard and impenetrable here as elsewhere, and this faint moisture is evidently caused by the rainfall draining down the slope of the rampart. Looking next outside the works for the source of such a supply, a spring will be found in a deep coombe, or bottom, about 800 yards--say, half a mile--from the nearest part of the fosse, reckoning in a straight line. Then, in bringing up water from this spring, which may be supposed to have been done in skins, a double ascent had to be made: first up on to the level plateau, here very narrow, next up the steep down itself. Those only who have had experience of the immense labour of watering cattle on the hills can estimate the work this must have been. An idea is obtained of the value of an elevated position in early warfare, when men for the sake of its advantage were found willing to submit to such toil. That, however, is not all--foraging parties fetching water must have been liable to be cut off from the main body; there were no cannon then to cover a sortie, and if the enemy were in sufficient force and took possession of the spring, they could compel an engagement, or drive the besieged to surrender rather than endure the tortures of thirst. So that a study of these English hills--widely different as are the conditions of time and place--may throw a strong light upon many an incident of ancient history. There are no traces remaining of any covered way or hollow dyke leading down the slope in the direction of the spring; but some such traces do seem to exhibit themselves in two places--at the rear of the earthwork along the ridge of the hill, and down the steepest and shortest ascent. The first does not come up to the entrenchment, being separated by a wide interval; the latter does, and may possibly have been used as a covered way, though now much obliterated and too shallow for the purpose. The rampart itself is in almost perfect preservation; in one spot the soil has slightly slipped, but form and outline are everywhere distinct.