sulated hill-top. "To be satisfied,"
said Sir George, "of the reason why the signal-fires should be kindled
on or beside a heap of stones, we have only to imagine a gale of wind to
have arisen when a fire was kindled on the bare ground. The fuel would
be blown about and dispersed, to the great annoyance of those who
attended. The plan for obviating the inconvenience thus occasioned which
would occur most naturally and readily would be to raise a heap of
stones, on either side of which the fire might be placed to windward;
and to account for the vitrification appearing all round the area, it is
only necessary to allow the inhabitants of the country to have had a
system of signals. A fire at one end might denote something different
from a fire at the other, or in some intermediate part. On some
occasions two or more fires might be necessary, and sometimes a fire
along the whole line. It cannot be doubted," he adds, "that the rampart
was originally formed with as much regularity as the nature of the
materials would allow, both in order to render it more durable, and to
make it serve the purposes of defence." This, I am afraid, is still
very unsatisfactory. A fire lighted along the entire line of a wall
inclosing nearly an acre of area could not be other than a very
attenuated, wire-drawn line of fire indeed, and could never possess
strength enough to melt the ponderous mass of rampart beneath, as if it
had been formed of wax or resin. A thousand loads of wood piled in a
ring round the summit of Knock Farril, and set at once into a blaze,
would wholly fail to affect the broad rampart below; and long ere even a
thousand, or half a thousand, loads could have been cut down, collected,
and fired, an invading enemy would have found time enough to moor his
fleet and land his forces, and possess himself of the lower country.
Again, the unbroken continuity of the vitrified line militates against
the signal-system theory. Fire trod so closely upon the heels of fire,
that the vitrescency induced by the one fire impinged on and mingled
with the vitrescency induced by the others beside it. There is no other
mode of accounting for the continuity of the fusion; and how could
definite meanings possibly be attached to the various parts of a line so
minutely graduated, that the centre of the fire kindled on any one
graduation could be scarce ten feet apart from the centre of the fire
kindled on any of its two neighboring graduations? Even by