eira proved no specific in the case. He was suffering
under excruciating headache, and had to stretch himself in his bed, with
eyes shut but sleepless, waiting till the fit should pass,--every pulse
that beat in his temples a throb of pain.

CHAPTER VIII.

Geology of Rum--Its curious Character illustrated--Rum famous for
Bloodstones--Red Sandstones--"Scratchings" in the Rocks--A
Geological Inscription without a Key--The Lizard--Vitality broken
into two--Illustrations--Speculation--Scuir More--Ascent of the
Scuir--The Bloodstones--An Illustrative Set of the Gem--M'Culloch's
Pebble--A Chemical Problem--The solitary Shepherd's House--Sheep
_versus_ Men--The Depopulation of Rum--A Haul of Trout--Rum Mode of
catching Trout--At Anchor in the Bay of Glenelg.

The geology of the island of Rum is simple, but curious. Let the reader
take, if he can, from twelve to fifteen trap-hills, varying from one
thousand to two thousand three hundred feet in height; let him pack them
closely and squarely together, like rum-bottles in a case-basket; let
him surround them with a frame of Old Red Sandstone, measuring rather
more than seven miles on the side, in the way the basket surrounds the
bottles; then let him set them down in the sea a dozen miles off the
land,--and he shall have produced a second island of Rum, similar in
structure to the existing one. In the actual island, however, there is a
defect in the inclosing basket of sandstone: the basket, complete on
three of its sides, wants the fourth: and the side opposite to the gap
which the fourth should have occupied is thicker than the two other
sides put together. Where I now write there is an old dark-colored
picture on the wall before me. I take off one of the four bars of which
the frame is composed,--the end-bar,--and stick it on to the end-bar
opposite, and then the picture is fully framed on two of its sides, and
doubly framed on a third, but the fourth side lacks framing altogether.
And such is the geology of the island of Rum. We find the one loch of
the island,--that in which the Betsey lies at anchor,--and the long
withdrawing valley, of which the loch is merely a prolongation,
occurring in the double sandstone bar: it seems to mark--to return to my
illustration--the line in which the superadded piece of frame has been
stuck on to the frame proper. The origin of the island is illustrated by
its structure: it has left its stor