Relation of the deep red stone of Cromarty to the Ichthyolite Beds
of the System--Ruins of a Fossil-charged Bed--Journey to Avoch--Red
Dye of the Boulder-clay distinct from the substance
itself--Variation of Coloring in the Boulder-clay Red Sandstone
accounted for--Hard-pan how formed--A reformed Garden--An ancient
Battle-field--Antiquity of Geologic and Human History
compared--Burn of Killein--Observation made in boyhood
confirmed--Fossil-nodules--Fine Specimen of _Coccosteus
decipiens_--Blank strata of Old Red--New View respecting the Rocks
of Black Isle--A Trip up Moray and Dingwall Friths--Altered color
of the Boulder-clay--Up the Auldgrande River--Scenery of the great
Conglomerate--Graphic Description--Laidlaw's Boulder--_Vaccinium
myrtillus_--Profusion of Travelled Boulders--The Boulder _Clach
Malloch_--Its zones of Animal and Vegetable Life.
The ravine excavated by the mill-dam showed me what I had never so well
seen before,--the exact relation borne by the deep red stone of the
Cromarty quarries to the ichthyolite beds of the system. It occupies the
same place, and belongs to the same period, as those superior beds of
the Lower Old Red Sandstone which are so largely developed in the cliffs
of Dunnet Head in Caithness, and of Tarbet Ness in Ross-shire, and which
were at one time regarded as forming, north of the Grampians, the
analogue of the New Red Sandstone. I paced it across the strata this
morning, in the line of the ravine, and found its thickness over the
upper fish-beds, though I was far from reaching its superior layers,
which are buried here in the sea, to be rather more than five hundred
feet. The fossiliferous beds occur a few hundred yards below the
dwelling-house of Rose Farm. They are not quite uncovered in the ravine;
but we find their places indicated by heaps of gray argillaceous shale,
mingled with their characteristic ichthyolitic nodules, in one of which
I found a small specimen of Cheiracanthus. The projecting edge of some
fossil-charged bed had been struck, mayhap, by an iceberg, and dashed
into ruins, just as the subsiding land had brought the spot within reach
of the attritive ice; and the broken heap thus detached had been shortly
afterwards covered up, without mixture of any other deposit, by the red
boulder-clay. On the previous day I had detected the fish-beds in
another new locality,--one of the ravines of the lawn of Cromarty
House,--where the gray shale, concealed by a covering of soil and sward
for centuries, had been laid bare during the storm by a swollen runnel,
and a small nodule, inclosing a characteristic plate of Pterichthys,
washed out. And my next object in to-day's journey, after exploring this
ravine of the boulder-clay, was to ascertain whether the beds did not
also occur in a ravine of the parish of Avoch, some eight or nine miles
away, which, when lying a-bed one night in Edinburgh, I remembered
having crossed when a boy, at a point which lies considerably out of the
ordinary route of the traveller. I had remarked on this occasion, as the
resuscitated recollection intimated, that the precipices of the Avoch
ravine bore, at the unfrequented point, the peculiar aspect which I
learned many years after to associate with the ichthyolitic member of
the system; and I was now quite as curious to test the truth of a sort
of vignette landscape, transferred to the mind at an immature period of
life, and preserved in it for full thirty years, as desirous to extend
my knowledge of the fossiliferous beds of a system to the elucidation of
which I had peculiarly devoted myself.
As the traveller reaches the flat moory uplands of the parish, where the
water stagnates amid heath and moss over a thin layer of peaty soil, he
finds the underlying boulder-clay, as shown in the chance sections,
spotted and streaked with patches of a grayish-white. There is the same
mixture of arenaceous and aluminous particles in the white as in the red
portions of the mass; for, as we see so frequently exemplified in the
spots and streaks of the Red Sandstone formations, whether Old or New,
the coloring matter has been discharged without any accompanying change
of composition in the substance which it pervaded;--evidence enough that
the red dye must be something distinct from the substance itself, just
as the dye of a handkerchief is a thing distinct from the silk or cotton
yarn of which the handkerchief has been woven. The stagnant water above,
acidulated by its various vegetable solutions, seems to have been in
some way connected with these appearances. In every case in which a
crack through the clay gives access to the oozing moisture, we see the
sides bleached, for several feet downwards, to nearly the color of
pipe-clay; we find the surface, too, when it has been divested of the
vegetable soil, presenting for yards together the appearance of sheets
of half-bleached linen: the red ground of the clay has been acted upon
by the percolating fluid, as the red ground of a Bandanna handkerchief
is acted upon through the openings in the perforated lead, by the
discharging chloride of lime. The peculiar chemistry through which these
changes are effected might be found, carefully studied, to throw much
light on similar phenomena in the older formations. There are quarries
in the New Red Sandstone in which almost every mass of stone presents a
different shade of color from that of its neighboring mass, and quarries
in the Old Red the strata of which we find streaked and spotted like
pieces of calico. And their variegated aspect seems to have been
communicated, in every instance, not during deposition, nor after they
had been hardened into stone but when, like the boulder-clay, they
existed in an intermediate state. Be it remarked, too, that the red clay
here,--evidently derived from the abrasion of the red rocks beneath,--is
in dye and composition almost identical with the substance on which, as
an unconsolidated sandstone, the bleaching influences, whatever their
character, had operated in the Palaeozoic period, so many long ages
before;--it is a repetition of the ancient experiment in the Old Red,
that we now see going on in the boulder-clay. It is further worthy of
notice, that the bleached lines of the clay exhibit, viewed
horizontally, when the overlying vegetable mould has been removed, and
the whitened surface in immediate contact with it paired off, a
polygonal arrangement, like that assumed by the cracks in the bottom of
clayey pools dried up in summer by the heat of the sun. Can these
possibly indicate the ancient rents and fissures of the boulder-clay,
formed, immediately after the upheaval of the land, in the first process
of drying, and remaining afterwards open enough to receive what the
uncracked portions of the surface excluded,--the acidulated bleaching
fluid?
The kind of ferruginous pavement of the boulder-clay known to the
agriculturist as _pan_, which may be found extending in some cases its
iron cover over whole districts,--sealing them down to barrenness, as
the iron and brass sealed down the stump of Nebuchadnezzar's tree,--is,
like the white strips and blotches of the deposit, worthy the careful
notice of the geologist. It serves to throw some light on the origin of
those continuous bands of clayey or arenaceous ironstone, which in the
older formations in which vegetable matter abounds, whether Oolitic or
Carboniferous, are of such common occurrence. The _pan_ is a stony
stratum, scarcely less indurated in some localities than sandstone of
the average hardness, that rests like a pavement on the surface of the
boulder-clay, and that generally bears atop a thin layer of sterile
soil, darkened by a russet covering of stunted heath. The binding cement
of the _pan_ is, as I have said, ferruginous, and seems to have been
derived from the vegetable covering above. Of all plants, the heaths are
found to contain most iron. Nor is it difficult to conceive how, in
comparatively flat tracts of heathy moor, where the surface water sinks
to the stiff subsoil, and on which one generation of plants after
another has been growing and decaying for many centuries, the minute
metallic particles, disengaged in the process of decomposition, and
carried down by the rains to the impermeable clay, should, by
accumulating there, bind the layer on which they rest, as is the nature
of ferruginous oxide, into a continuous stony crust. Wherever this _pan_
occurs, we find the superincumbent soil doomed to barrenness,--arid and
sun-baked during the summer and autumn months, and, from the same cause,
overcharged with moisture in winter and spring. My friend Mr. Swanson,
when schoolmaster of Nigg, found a large garden attached to the
school-house so inveterately sterile as to be scarce worth cultivation;
a thin stratum of mould rested on a hard impermeable pavement of _pan_,
through which not a single root could penetrate to the tenacious but not
unkindly subsoil below. He set himself to work in his leisure hours, and
bit by bit laid bare and broke up the pavement. The upper mould, long
divorced from the clay on which it had once rested, was again united to
it; the piece of ground began gradually to alter its character for the
better; and when I last passed the way, I found it, though in a state of
sad neglect, covered by a richer vegetation than it had ever borne under
the more careful management of my friend. This ferruginous pavement of
the boulder-clay may be deemed of interest to the geologist, as a
curious instance of deposition in a dense medium, and as illustrative
of the changes which may be effected on previously existing strata,
through the agency of an overlying vegetation.
I passed, on my way, through the ancient battle-field to which I have
incidentally referred in the story of the Miller of Resolis.[17] Modern
improvement has not yet marred it by the plough; and so it still bears
on its brown surface many a swelling tumulus and flat oblong mound,
and--where the high road of the district passes along its eastern
edge--the huge gray cairn, raised, says tradition, over the body of an
ancient Pictish king. But the contest of which it was the scene belongs
to a profoundly dark period, ere the gray dawn of Scottish history
began. As shown by the remains of ancient art occasionally dug up on the
moor, it was a conflict of the times of the stone battle-axe, the flint
arrow-head, and the unglazed sepulchral urn, unindebted for aught of its
symmetry to the turning-lathe,--times when there were heroes in
abundance, but no scribes. And the cairn, about a hundred feet in length
and breadth, by about twenty in height, with its long hoary hair of
overgrown lichen waving in the breeze, and the trailing club-moss
shooting upwards from its base along its sides, bears in its every
lineament full mark of its great age. It is a mound striding across the
stream of centuries, to connect the past with the present. And yet,
after all, what a mere matter of yesterday its extreme antiquity is! My
explorations this morning bore reference to but the later eras of the
geologist; the portion of the geologic volume which I was attempting to
decipher and translate formed the few terminal paragraphs of its
concluding chapter. And yet the _finis_ had been added to them for
thousands of years ere this latter antiquity began. The boulder-clay had
been formed and deposited; the land, in rising over the waves, had had
many a huge pebble washed out of its last formed red stratum, or dropped
upon it by ice-floes from above; and these pebbles lay mottling the
surface of this barren moor for mile after mile, bleaching pale to the
rains and the sun, as the meagre and mossy soil received, in the lapse
of centuries, its slow accessions of organic matter, and darkened around
them. And then, for a few brief hours, the heath, no longer solitary,
became a wild scene of savage warfare,--of waving arms and threatening
faces,--and of human lives violently spilled, gushing forth in blood;
and, when all was over, the old weathered boulders were heaped up above
the slain, and there began a new antiquity in relation to the pile in
its gathered state, that bore reference to man's short lifetime, and to
the recent introduction of the species. The child of a few summers
speaks of the events of last year as long gone by; while his father
advanced into middle life, regards them as still fresh and recent.
I reached the Burn of Killein,--the scene of my purposed
explorations,--where it bisects the Inverness road; and struck down the
rocky ravine, in the line of the descending strata and the falling
streamlet, towards the point at which I had crossed it so many years
before. First I passed along a thick bed of yellow stone,--next over a
bed of stratified clay. "The little boy," I said, "took correct note of
what he saw, though without special aim at the time, and as much under
the guidance of a mere observative instinct as Dame Quickly, when she
took note of the sea-coal fire, the round table, the parcel-gilt goblet,
and goodwife Keech's dish of prawns dressed in vinegar, as adjuncts of
her interview with old Sir John when he promised to marry her. These
are unequivocally the ichthyolitic beds, whether they contain
ichthyolites or no." The first nodule I laid open presented inside
merely a pale oblong patch in the centre, which I examined in vain with
the lens, though convinced of its organic origin, for a single scale.
Proceeding farther down the stream, I picked a nodule out of a second
and lower bed, which contained more evidently its organism,--a
finely-reticulated fragment, that at first sight reminded me of some
delicate festinella of the Silurian system. It proved, however, to be
part of the tail of a Cheiracanthus, exhibiting--what is rarely
shown--the interior surfaces of those minute rectangular scales which in
this genus lie over the caudal fin, ranged in right lines. A second
nodule presented me with the spines of _Diplacanthus striatus_; and
still farther down the stream,--for the beds are numerous here, and
occupy in vertical extent very considerable space in the system,--I
detected a stratum of bulky nodules charged with fragments of
Coccosteus, belonging chiefly to two species,--_Coccosteus decipiens_
and _Coccosteus cuspidatus_. All the specimens bore conclusive evidence
regarding the geologic place and character of the beds in which they
occur; and in one of the number, a specimen of _Coccosteus decipiens_,
sufficiently fine to be transferred to my knapsack, and which now
occupies its corner in my little collection, the head exhibits all its
plates in their proper order, and the large dorsal plate, though
dissociated from the nail-like attachment of the nape, presents its
characteristic breadth entire. It was the plates of this species, first
found in the flagstones of Caithness, which were taken for those of a
fresh-water tortoise; and hence apparently its specific name,
_decipiens_;--it is the _deceiving_ Coccosteus. I disinterred, in the
course of my explorations, as many nodules as lay within reach,--now and
then longing for a pickaxe, and a companion robust and persevering
enough to employ it with effect; and after seeing all that was to be
seen in the bed of the stream and the precipices, I retraced my steps up
the dell to the highway. And then, striking off across the moor to the
north,--ascending in the system as I climbed the eminence, which forms
here the central ridge of the old Maolbuie Common,--I spent some little
time in a quarry of pale red sandstone, known, from the moory height on
which it has been opened, as the quarry of the Maolbuie. But here, as
elsewhere, the folds of that upper division of the Lower Old Red in
which it has been excavated contain nothing organic. Why this should be
so universally the case,--for in Caithness, Orkney, Cromarty, and Ross,
wherever, in short, this member of the system is unequivocally
developed, it is invariably barren of remains,--cannot, I suspect, be
very satisfactorily explained. Fossils occur both over and under it, in
rocks that seem as little favorable to their preservation; but during
that intervening period which its blank strata represent, at least the
_species_ of all the ichthyolites of the system seem to have changed,
and, so far as is yet known, the _genus_ Coccosteus died out entirely.
The Black Isle has been elaborately described in the last Statistical
Account of the Parish of Avoch as comprising at least the analogues of
three vast geologic systems. The Great Conglomerate, and the thick bed
of coarse sandstone of corresponding character that lies over it,
compose all which is not primary rock of that south-eastern ridge of the
district which forms the shores of the Moray Frith; and _they_ are
represented in the Account as Old Red Sandstone proper. Then, next in
order,--forming the base of a parallel ridge,--come those sandstone and
argillaceous bands to which the ichthyolite beds belong; and these
though at the time the work appeared their existence in the locality
could be but guessed at, are described as representatives of the Coal
Measures. Last of all there occur those superior sandstones of the Lower
Old Red formation in which the quarry of the Maolbuie has been opened,
and which are largely developed in the central or _backbone_ ridge of
the district. "And these," says the writer, "we have little hesitation
in assigning to the _New_ Red, or variegated Sandstone formation." I
remember that some thirteen years ago,--in part misled by authority, and
in part really afraid to represent beds of such an enormous aggregate
thickness as all belonging to one inconsiderable formation,--for such
was the character of the Old Red Sandstone at the time,--I ventured,
though hesitatingly, and with less of detail, on a somewhat similar
statement regarding the sandstone deposits of the parish of Cromarty.
But true it is, notwithstanding, that the stratified rocks of the Black
Isle are composed generally, not of the analogues of three systems, but
of merely a fractional portion of a single system,--a fact previously
established in other parts of the district, and which my discovery of
this day in the Burn of Killein served yet farther to confirm in
relation to that middle portion of the tract in which the parish of
Avoch is situated. The geologic records, unlike the Sybilline books,
grow in volume and number as one pauses and hesitates over them;
demanding, however, with every addition to their bulk, a larger and yet
larger sum of epochs and of ages.
The sun had got low in the western sky, and I had at least some eight or
nine miles of rough road still before me; but the day had been a happy
and not unsuccessful one, and so its hard work had failed to fatigue.
The shadows, however, were falling brown and deep on the bleak Maolbuie,
as I passed, on my return, the solitary cairn; and it was dark night
long ere I reached Cromarty. Next morning I quitted the town for the
upper reaches of the Frith, to examine yet further the superficial
deposits and travelled boulders of the district.
I landed at Invergordon a little after noon, from the Leith steamer,
that, on its way to the upper ports of the Moray and Dingwall Friths,
stops at Cromarty for passengers every Wednesday; and then passing
direct through the village, I took the western road which winds along
the shore towards Strathpeffer, skirting on the right the ancient
province of the Munroes. The day was clear and genial; and the
wide-spreading woods of this part of the country, a little touched by
their autumnal tints of brown and yellow, gave a warmth of hue to the
landscape, which at an earlier season it wanted. A few slim streaks of
semi-transparent mist, that barred the distant hill-peaks, and a few
towering piles of intensely white cloud, that shot across the deep blue
of the heavens, gave warning that the earlier part of the day was to be
in all probability the better part of it, and that the harvest of
observation which it was ultimately to yield might be found to depend on
the prompt use made of the passing hour. What first attracts the
attention of the geologist, in journeying westwards, is the altered
color of the boulder-clay, as exhibited in ditches by the way-side, or
along the shore. It no longer presents that characteristic red
tint,--borrowed from the red sandstone beneath,--so prevalent over the
Black Isle, and in Easter Ross generally; but is of a cold leaden hue,
not unlike that which it wears above the Coal Measures of the south, or
over the flagstones of Caithness. The altered color here is evidently a
consequence of the large development, in Ferindonald and Strathpeffer,
of the ichthyolitic members of the Old Red, existing chiefly as fetid
bituminous breccias and dark-colored sandstones: the boulder-clay of
the locality forms the dressings, not of red, but of blackish-gray
rocks; and, as almost everywhere else in Scotland, its trail lies to the
east of the strata, from which it was detached in the character of an
impalpable mud by the age-protracted grindings of the denuding agent. It
abounds in masses of bituminous breccia, some of which, of great size,
seem to have been drifted direct from the valley of Strathpeffer, and
are identical in structure and composition with the rock in which the
mineral springs of the Strath have their rise, and to which they owe
their peculiar qualities.
After walking on for about eight miles, through noble woods and a lovely
country, I struck from off the high road at the pretty little village of
Evanton, and pursued the course of the river Auldgrande, first through
intermingled fields and patches of copsewood, and then through a thick
fir wood, to where the bed of the stream contracts from a
boulder-strewed bottom of ample breadth, to a gloomy fissure, so deep
and dark, that in many places the water cannot be seen, and so narrow,
that the trees which shoot out from the opposite sides interlace their
branches atop. Large banks of the gray boulder-clay, laid open by the
river, and charged with fragments of dingy sandstone and dark-colored
breccia, testify, along the lower reaches of the stream, to the near
neighborhood of the ichthyolitic member of the Old Red; but where the
banks contract, we find only its lowest member, the Great Conglomerate.
This last is by far the most picturesque member of the system,--abrupt
and bold of outline in its hills, and mural in its precipices. And
nowhere does it exhibit a wilder or more characteristic beauty than at
the tall narrow portal of the Auldgrande, where the river,--after
wailing for miles in a pent-up channel, narrow as one of the lanes of
old Edinburgh, and hemmed in by walls quite as perpendicular, and
nearly twice as lofty,--suddenly expands, first into a deep brown pool,
and then into a broad tumbling stream, that, as if permanently affected
in temper by the strict severity of the discipline to which its early
life had been subjected, frets and chafes in all its after course, till
it loses itself in the sea. The banks, ere we reach the opening of the
chasm, have become steep, and wild, and densely wooded; and there stand
out on either hand, giant crags, that plant their iron feet in the
stream; here girdled with belts of rank succulent shrubs, that love the
damp shade and the frequent drizzle of the spray; and there hollow and
bare, with their round pebbles sticking out from the partially
decomposed surface, like the piled-up skulls in the great underground
cemetery of the Parisians. Massy trees, with their green fantastic roots
rising high over the scanty soil, and forming many a labyrinthine recess
for the frog, the toad, and the newt, stretch forth their gnarled arms
athwart the stream. In front of the opening, with but a black deep pool
between, there lies a midway bank of huge stones. Of these, not a few of
the more angular masses still bear, though sorely worn by the torrent,
the mark of the blasting iron, and were evidently tumbled into the chasm
from the fields above. But in the chasm there was no rest for them, and
so the arrowy rush of the water in the confined channel swept them down
till they dropped where they now lie, just where the widening bottom
first served to dissipate the force of the current. And over the sullen
pool in front we may see the stern pillars of the portal rising from
eighty to a hundred feet in height, and scarce twelve feet apart, like
the massive obelisks of some Egyptian temple; while, in gloomy vista
within, projection starts out beyond projection, like column beyond
column in some narrow avenue of approach to Luxor or Carnac. The
precipices are green, with some moss or byssus, that like the miner,
chooses a subterranean habitat,--for here the rays of the sun never
fall; the dead, mossy water beneath, from which the cliffs rise so
abruptly, bears the hue of molten pitch; the trees, fast anchored in the
rock, shoot out their branches across the opening, to form a thick
tangled roof, at the height of a hundred and fifty feet overhead; while
from the recesses within, where the eye fails to penetrate, there issues
a combination of the strangest and wildest sounds ever yet produced by
water: there is the deafening rush of the torrent, blent as if with the
clang of hammers, the roar of vast bellows, and the confused gabble of a
thousand voices. The sun, hastening to its setting, shone red, yet
mellow, through the foliage of the wooded banks on the west, where, high
above, they first curve from the sloping level of the fields, to bend
over the stream; or fell more direct on the jutting cliffs and bosky
dingles opposite, burnishing them as if with gold and fire; but all was
coldly-hued at the bottom, where the torrent foamed gray and chill under
the brown shadow of the banks; and where the narrow portal opened an
untrodden way into the mysterious recesses beyond, the shadow deepened
almost into blackness. The scene lacked but a ghost to render it
perfect. An apparition walking from within like the genius in one of
Goldsmith's essays "along the surface of the water," would have
completed it at once.
Laying hold of an overhanging branch, I warped myself upwards from the
bed of the stream along the face of a precipice, and, reaching its
sloping top, forced my way to the wood above, over a steep bank covered
with tangled underwood, and a slim succulent herbage, that sickened for
want of the sun. The yellow light was streaming through many a shaggy
vista, as, threading my way along the narrow ravine as near the steep
edge as the brokenness of the ground permitted, I reached a huge mass
of travelled rock, that had been dropped in the old boulder period
within a yard's length of the brink. It is composed of a characteristic
granitic gneiss of a pale flesh-color, streaked with black, that, in the
hand specimen, can scarce be distinguished from a true granite, but
which, viewed in the mass, presents, in the arrangement of its intensely
dark mica, evident marks of stratification, and which is remarkable,
among other things, for furnishing almost all the very large boulders of
this part of the country. Unlike many of the granitic gneisses, it is a
fine solid stone, and would cut well. When I had last the pleasure of
spending a few hours with the late Mr. William Laidlaw, the trusted
friend of Sir Walter Scott, he intimated to me his intention,--pointing
to a boulder of this species of gneiss,--of having it cut into two
oblong pedestals, with which he purposed flanking the entrance to the
mansion-house of the chief of the Rosses,--the gentleman whose property
he at that time superintended. It was, he said, both in appearance and
history, the most remarkable stone on the lands of Balnagown; and so he
was desirous that it should be exhibited at Balnagown Castle to the best
advantage. But as he fell shortly after into infirm health, and resigned
his situation, I know not that he ever carried his purpose into effect.
The boulder here, beside the chasm, measures about twelve feet in length
and breadth, by from five to six in height, and contains from eight to
nine hundred cubic feet of stone. On its upper table-like surface I
found a few patches of moss and lichen, and a slim reddening tuft of the
_Vaccinium myrtillus_, still bearing, late as was the season, its
half-dozen blaeberries. This pretty little plant occurs in great
profusion along the steep edges of the Auldgrande, where its delicate
bushes, springing up amid long heath and ling, and crimsoned by the
autumnal tinge, gave a peculiar warmth and richness this evening to
those bosky spots under the brown trees, or in immediate contact with
the dark chasm on which the sunlight fell most strongly; and on all the
more perilous projections, I found the dark berries still shrivelling on
their stems. Thirty years earlier I would scarce have left them there;
and the more perilous the crag on which they had grown, the more
deliciously would they have eaten. But every period of life has its own
playthings; and I was now chiefly engaged with the deep chasm and the
huge boulder. Chasm and boulder had come to have greatly more of
interest to me than the delicate berries, or than even that sovereign
dispeller of ennui and low spirits, an adventurous scramble among the
cliffs.
In what state did the chasm exist when the huge boulder,--detached,
mayhap, at the close of a severe frost, from some island of the
archipelago that is now the northern Highlands of Scotland,--was
suffered to drop beside it, from some vast ice-floe drifting eastwards
on the tide? In all probability merely as a fault in the Conglomerate,
similar to many of those faults which in the Coal Measures of the
southern districts we find occupied by continuous dikes of trap. But in
this northern region, where the trap-rocks are unknown, it must have
been filled up with the boulder-clay, or with some still more ancient
accumulation of debris. And when the land had risen, and the streams,
swollen into rivers, flowed along the hollows which they now occupy, the
loose rubbish would in the lapse of ages gradually wash downwards to the
sea, as the stones thrown from the fields above were washed downwards in
a later time; and thus the deep fissure would ultimately be cleared out.
The boulder-stones lie thickly in this neighborhood, and over the
eastern half of Ross-shire, and the Black Isle generally; though for
the last century they have been gradually disappearing from the more
cultivated tracts on which there were fences or farm-steadings to be
built, or where they obstructed the course of the plough. We found them
occurring in every conceivable situation,--high on hill-sides, where the
shepherd crouches beside them for shelter in a shower,--deep in the open
sea, where they entangle the nets of the fisherman,--on inland moors,
where in some remote age they were painfully rolled together, to form
the Druidical circle or Picts'-house,--or on the margin of the coast,
where they had been piled over one another at a later time, as
protecting bulwarks against the encroachments of the waves. They lie
strewed more sparingly over extended plains, or on exposed heights, than
in hollows sheltered from the west by high land, where the current, when
it dashed high on the hill-sides, must have been diverted from its
easterly course, and revolved in whirling eddies. On the top of the fine
bluff hill of Fyrish, which I so admired to-day, each time I caught a
glimpse of its purple front through the woods, and which shows how noble
a mountain the Old Red Sandstone may produce, the boulders lie but
sparsely. I especially marked, however, when last on its summit, a
ponderous traveller of a vividly green hornblende, resting on a bed of
pale yellow sandstone, fully a thousand feet over the present high-water
level. But towards the east, in what a seaman would term the _bight_ of
the hill, the boulders have accumulated in vast numbers. They lie so
closely piled along the course of the river Alness, about half a mile
above the village, that it is with difficulty the waters, when in flood,
can force their passage through. For here, apparently, when the tide
swept along the hill-side, many an ice-floe, detained in the shelter by
the revolving eddy, dashed together in rude collision, and shook their
stony burdens to the bottom. Immediately to the east of the low
promontory on which the town of Cromarty is built there is another
extensive accumulation of boulders, some of them of great size. They
occupy exactly the place to which I have oftener than once seen the
drift-ice of the upper part of the Cromarty Frith, set loose by a thaw,
and then carried seawards by the retreating tide, forced back by a
violent storm from, the east, and the fragments ground against each
other into powder. And here, I doubt not, of old, when the sea stood
greatly higher than now, and the ice-floes were immensely larger and
more numerous than those formed, in the existing circumstances, in the
upper shallows of the Frith, would the fierce north-east have charged
home with similar effect, and the broken masses have divested themselves
of their boulders.
The Highland chieftain of one of our old Gaelic traditions conversed
with a boulder-stone, and told to it the story which he had sworn never
to tell to man. I too, after a sort, have conversed with boulder-stones,
not, however, to tell them any story of mine, but to urge them to tell
theirs to me. But, lacking the fine ear of Hans Anderson, the Danish
poet, who can hear flowers and butterflies talk, and understand the
language of birds, I have as yet succeeded in extracting from them no
such articulate reply
"As Memnon's image, long renowned of old
By fabling Nilus, to the quivering touch
Of Titan's ray, with each repulsive string
Consenting, sounded through the warbling air."
And yet, who can doubt that, were they a little more communicative,
their stories of movement in the past, with the additional circumstances
connected with the places which they have occupied ever since they gave
over travelling, would be exceedingly curious ones? Among the boulder
group to the east of Cromarty, the most ponderous individual stands so
exactly on the low-water line of our great Lammas tides, that though its
shoreward edge may be reached dry-shod from four to six times every
twelvemonth, no one has ever succeeded in walking dry shod round it. I
have seen a strong breeze from the west, prolonged for a few days,
prevent its drying, when the Lammas stream was at its point of lowest
ebb, by from a foot to eighteen inches,--an indication, apparently, that
to that height the waters of the Atlantic may be heaped up against our
shores by the impulsion of the wind. And the recurrence, during at least
the last century, of certain ebbs each season, which, when no disturbing
atmospheric phenomena interfere with their operation, are sure to lay it
dry, demonstrate, that during that period no change, even the most
minute, has taken place on our coasts, in the relative levels of sea and
shore. The waves have considerably encroached, during even the last
half-century, on the shores immediately opposite; but it must have been,
as the stone shows, simply by the attrition of the waves, and the
consequent lowering of the beach,--not through any rise in the ocean, or
any depression of the land.
The huge boulder here has been known for ages as the _Clach Malloch_, or
accursed stone, from the circumstance, says tradition, that a boat was
once wrecked upon it during a storm, and the boatmen drowned. Though
little more than seven feet in height, by about twelve in length, and
some eight or nine in breadth, its situation on the extreme line of ebb
imparts a peculiar character to the various productions, animal and
vegetable, which we find adhering to it. They occur in zones, just as on
lofty hills the botanist finds his agricultural, moorland, and alpine
zones rising in succession as he ascends, the one over the other. At its
base, where the tide rarely falls, we find two varieties of _Lobularia
digitata_, dead man's hand, the orange colored and the pale, with a
species of sertularia; and the characteristic vegetable is the
rough-stemmed tangle, or cuvy. In the zone immediately above the lowest,
these productions disappear; the characteristic animal, if animal it be,
is a flat yellow sponge,--the _Halichondria papillaris_,--remarkable
chiefly for its sharp siliceous spicula and its strong phosphoric smell;
and the characteristic vegetable is the smooth-stemmed tangle, or
queener. In yet another zone we find the common limpet and the vesicular
kelp-weed; and the small gray balanus and serrated kelp-weed form the
productions of the top. We may see exactly the same zones occurring in
broad belts along the shore,--each zone indicative of a certain
overlying depth of water; but it seems curious enough to find them all
existing in succession on one boulder. Of the boulder and its story,
however, more in my next.