dinal lining on the softer and finer-grained pebbles of
the boulder-clay, that I have come to regard it as that special
characteristic of the deposit on which I can most surely rely for
purposes of identification. I am never quite certain of the boulder-clay
when I do not detect it, nor doubtful of the true character of the
deposit when I do. When examining, for instance, the accumulation of
broken Liasic materials in the neighborhood of Banff, I made it my first
care to ascertain whether the bank inclosed fragments of stone or shale
bearing the longitudinal markings; and felt satisfied, on finding that
it did, that I had discovered the period of its re-formation.

CHAPTER VI.

Organisms of the Boulder-clay not unequivocal--First Impressions of
the Boulder-clay--Difficulty of accounting for its barrenness of
Remains--Sir Charles Lyell's reasoning--A Fact to the
contrary--Human Skull dug from a Clay-bank--The Author's Change of
Belief respecting Organic Remains of the Boulder-clay--Shells from
the Clay at Wick--Questions respecting them settled--Conclusions
confirmed by Mr. Dick's Discoveries at Thurso--Sir John Sinclair's
Discovery of Boulder-clay Shells in 1802--Comminution of the Shells
illustrated--_Cyprina islandica_--Its Preservation in larger
Proportions than those of other Shells accounted for--Boulder-clays
of Scotland reformed during the existing Geological Epoch--Scotland
in the Period of the Boulder-clay "merely three detached groups of
Islands"--Evidence of the Subsidence of the Land in
Scotland--Confirmed by Rev. Mr. Cumming's conclusion--High-lying
Granite Boulders--Marks of a succeeding elevatory
Period--Scandinavia now rising--Autobiography of a Boulder
desirable--A Story of the Supernatural.

For the greater part of a quarter of a century I had been finding
organisms in abundance in the boulder-clay, but never anything organic
that unequivocally belonged to its own period. I had ascertained that it
contains in Ross and Cromarty nodules of the Old Red Sandstone, which
bear inside, like so many stone coffins, their well laid out skeletons
of the dead; but then the markings on their surface told me that when
the boulder-clay was in the course of deposition, they had been exactly
the same kind of nodules that they are now. In Moray, it incloses, I had
found, organisms of the Lias; but _they_ also testify that they p