e were already there. How long they had stood in their silence
before our chronometer began to run we cannot even guess.

At Cavancarragh, on the shoulder of Toppid Mountain, some four miles
from Enniskillen, there is one of these circles; a ring of huge stone
boulders with equal spaces between stone and stone. A four-fold avenue
of great blocks stretches away from it along the shoulder of the hill,
ending quite abruptly at the edge of a ravine, the steep channel of a
torrent. It looks as if the river, gradually undermining the hillside,
had cut the avenue in halves, so that the ravine seems later in date
than the stones. But that we cannot be quite sure of. This, however, we
do certainly know: that since the avenue of boulders and the circle of
huge red stones were ranged in order, a covering of peat in some parts
twelve feet thick has grown around and above them, hiding them at last
altogether from the day. In places the peat has been cut away again,
leaving the stones once more open to the light, standing, as they always
stood, on the surface of the clay.

Here again we get the same measurement. At eight hundred annual layers
to the foot, and with twelve feet of peat, we have nine thousand six
hundred years,--not for the age of the stone circles, but for that part
of their age which we are able to measure. For we know not how long they
were there before the peat began to grow. It may have been a few years;
it may have been a period as great or even greater than the ten thousand
years we are able to measure.

The peat gradually displaced an early forest of giant oaks. Their stems
are still there, standing rooted in the older clay. Where they once
stood no trees now grow. The whole face of the land has changed. Some
great change of climate must lie behind this vanishing of vast forests,
this gradual growth of peat-covered moors. A dry climate must have
changed to one much damper; heat must have changed to cold, warm winds
to chilly storms. In the southern promontories, among red sandstone
hills, still linger survivors of that more genial clime--groves of
arbutus that speak of Greece or Sicily; ferns, as at Killarney, found
elsewhere only in the south, in Portugal, or the Canary Islands.

[Illustration: Muckross Abbey, Killarney.]

On the southwestern horizon from Toppid Mountain, when the sky is clear
after rain, you can trace the outline of the Curlew hills, our
southern limit of view from Knocknarea. Up to the fo