he tribe. But, although the means or ingenuity of the
builders did not extend so far as to provide a roof, they supplied the
want by constructing apartments in the interior of the walls of the
tower itself. The circumvallation formed a double enclosure, the inner
side of which was, in fact, two feet or three feet distant from the
other, and connected by a concentric range of long flat stones, thus
forming a series of concentric rings or stories of various heights,
rising to the top of the tower. Each of these stories or galleries has
four windows, facing directly to the points of the compass, and rising
of course regularly above each other. These four perpendicular ranges
of windows admitted air, and, the fire being kindled, heat, or smoke at
least, to each of the galleries. The access from gallery to gallery is
equally primitive. A path, on the principle of an inclined plane, turns
round and round the building like a screw, and gives access to the
different stories, intersecting each of them in its turn, and thus
gradually rising to the top of the wall of the tower. On the outside
there are no windows; and I may add, that an enclosure of a square, or
sometimes a round form, gave the inhabitants of the Burgh an opportunity
to secure any sheep or cattle which they might possess.

Such is the general architecture of that very early period when the
Northmen swept the seas, and brought to their rude houses, such as I
have described them, the plunder of polished nations. In Zetland there
are several scores of these Burghs, occupying in every case, capes,
headlands, islets, and similar places of advantage singularly well
chosen. I remember the remains of one upon an island in a small lake
near Lerwick, which at high tide communicates with the sea, the access
to which is very ingenious, by means of a causeway or dike, about three
or four inches under the surface of the water. This causeway makes a
sharp angle in its approach to the Burgh. The inhabitants, doubtless,
were well acquainted with this, but strangers, who might approach in a
hostile manner, and were ignorant of the curve of the causeway, would
probably plunge into the lake, which is six or seven feet in depth at
the least. This must have been the device of some Vauban or Cohorn of
those early times.

The style of these buildings evinces that the architect possessed
neither the art of using lime or cement of any kind, nor the skill to
throw an arch, construct a roof