record
is cited. He now offers guesses as to the stones "in the so-called
pavements and causeways." First, the causeways may have probably been
made "during the construction of the tower with its central pole," (here
the cairn is a habitable beacon, habitable on all hypotheses,) or, again,
"perhaps at the time of its demolition" about which demolition we know
nothing, {47a} except that the most of the stones are not now _in situ._

Several authentic stone crannogs in Scotland, as to which we have
information, possessed no central pole, but had a stone causeway, still
extant, leading, _e.g._ from the crannog to the shore of the Ashgrove
loch, "a causeway of rough blocks of sandstone slabs." {47b} If one
stone crannog had a stone causeway, why should this ancient inhabited
cairn or round tower not possess a stone causeway? Though useless at
high water, at low water it would afford better going. In a note to
_Ivanhoe_, and in his Northern tour of 1814, Scott describes a stone
causeway to a broch on an artificial island in Loch Cleik-him-in, near
Lerwick. Now this loch, says Scott, was, at the time when the broch was
inhabited, open to the flow of tide water.

As people certainly did live on these structures of Langbank and Dunbuie
during the broch and crannog age (centuries 5-12) it really matters not
to our purpose _why_ they did so, or _how_ they did so. Let us suppose
that the circular wall of the stone superstructure slanted inwards, as is
not unusual. In that case the habitable area at the top may be reduced
to any extent that is thought probable, with this limitation:--the
habitable space must not be too small for the accommodation of the
persons who filled up the eastern third of an area of from twelve to
fourteen feet in breadth, and in some places a foot in thickness, with a
veritable kitchen-midden, of "broken and partially burned bones of
various animals, shells of edible molluscs, and a quantity of ashes and
charcoal . . . ." {48}

But Dr. Munro assures me that the remains discovered could be deposited
in a few years of regular occupancy by two or three persons.

The structure certainly yielded habitable space enough to accommodate the
persons who, in the fifth to twelfth centuries, left these traces of
their occupancy. Beyond that fact I do not pretend to estimate the
habitable area.

Why did these people live on this structure in the fifth to twelfth
centuries? Almost certainly, not for the pur