With the same class also may be reckoned certain structures described by Pennant as the repositories of the ashes of sacrifices. One of these, within a few miles of Edinburgh, in the neighbourhood of Borthwick Castle, was brought to light by the plough coming in contact with its rough masonry, at a depth of only a foot below the surface. It may be described as pear-shaped, and with a passage continuing from the narrow end, measuring fifteen feet in length by two and a half in breadth. The masonry was of the rudest description, and nearly the whole space between the walls was filled with a rich black mould, irregularly interspersed with charcoal, fragments of bone, and the teeth of sheep and oxen.[104] A similar building was discovered about the same time in the east of Fife, and one closely corresponding to it has recently been disclosed by railway operations at Newstead, in the neighbourhood of Melrose. In this, as in the example above referred to, the narrow passage pointed nearly north-west; and its masonry was equally rude; but among its contents were various carved stones, apparently corresponding with Roman remains frequently found in that neighbourhood, and one in particular with the cable-pattern, or woollen fillet, so commonly employed by the Anglo-Roman sculptors. Akin to such subterranean dwellings are the natural and artificial caves which, in Scotland, as in most other countries, have supplied hiding-places, retreats for anchorites, and even permanent native dwellings, and may be described along with this class, though belonging to many different periods. Such caves abound in Scotland, and especially along the coast, but in general their interest arises rather from the associations of popular traditions, than from any intrinsic peculiarity of character pertaining to them. Few such retreats are more remarkable, either for constructive art, or historic associations, than the well-known caves beneath the old tower of Hawthornden, near Edinburgh. They have been hewn, with great labour and ingenuity, in the rocky cliff which overhangs the river Esk. No tradition preserves the history or date of their execution, but concealment was evidently the chief design of the excavators. The original entrance is most ingeniously made in the shaft of a very deep draw-well, sunk in the court-yard of the castle, and from its manifest utility as the ordinary and indispensable appendage of the fortress, it most effectually conceals its adaptation as a means of ingress and communication with the rock chambers beneath. These are of various forms and sizes, and one in particular is pierced with a series of square recesses, somewhat resembling the columbaria of a Roman tomb, but assigned by popular tradition as the library of its later owner, Drummond the Scottish poet. Whatever was the purpose for which these were thus laboriously cut, the example is not singular. A large cave in Roxburghshire,