No matter what the character of the material to be excavated, the ditch clings closely to the Wall on all the lower ground. It is hewn through basalt, sandstone and limestone with equal indifference. The Wall is constructed in the method usual with the Romans; that is to say, it consists of a rubble core mixed with mortar, faced on each side by masonry blocks. The stone used for the facing is a species of sandstone. The size of the blocks {27} is very regular: 8 or 9 inches by 10 or 11 inches on the face, and sometimes as much as 20 inches long. The length is tapered off to form a wedge-shape, so as to bind well into the core of the Wall. After a little practice, one can readily recognize the Wall stones where they have been made use of in later buildings and in fences. The front surface of the stones is often tooled in a rough pattern, with diagonal lines, known as "diamond broaching," or with waved lines, known as "feather broaching." The latter has been held to be specially characteristic of Severus's work of reconstruction. The Wall was built on a foundation of flat flagstones, laid on the rock. Upon these, one or two courses of facing-stones were set in place, and into the intervening space was poured a mass of fluid mortar. Rough stones of any shape--chiefly whinstones--were then introduced into the mortar, which, when dry, bound all together in one solid mass. So course after course was added until the required height was reached. On gently undulating ground the courses of the Wall keep parallel to the surface of the ground; on steep slopes the courses are laid horizontally. The colour of the stone is very varied; individual stones are brownish, yellowish, reddish, grey; and the general impression varies also because the stone has not always "weathered" in the same way. {28} Like the Great Wall of China, the Wall disregards obstacles, climbs hills, and crosses valleys and streams, choosing always the greatest possible heights to traverse. Camden says of it: "Verily, I have seene the tract of it, over the high pitches and steepe descents of hills wonderfully rising and falling." It is set for the most part in very beautiful surroundings, sometimes in the peaceful and fertile lowlands, sometimes on the lonely barren hills, with wide vistas stretching out to north and south. The highest hill it climbs is Winshields, 1230 feet high. Unlike the Great Wall of China, it has suffered much at the hands of the destroyer, and for miles together scarcely a trace is to be seen. In the more or less populated districts it has been used as a quarry, and farm-houses, churches, and pele-towers have been built with its stones. For 19 miles out of Newcastle the road (made by General Wade in 1753, from Newcastle to Carlisle) runs chiefly on the foundations of the Wall, and much of the Wall was pulled down then, to give place to "military necessities." This road I shall in future refer to as "Wade's Road."