CHAPTER X.

Speculations in the Old Red Sandstone, and their Character.--George,

first Earl of Cromarty.--His Sagacity as a Naturalist at fault in

one Instance.--Sets himself to dig for Coal in the Lower Old lied

Sandstone.--Discovers a fine Artesian Well.--Value of Geological

Knowledge in an economic View.--Scarce a Secondary Formation in the

Kingdom in which Coal has not been sought for.--Mineral Springs

of the Lower Old Red Sandstone.--Strathpeffer.--Its Peculiarities

whence derived.--Chalybeate Springs of Easter Ross and the Black

Isle.--Petrifying Springs.--Building-Stone and Lime of the Old Red

Sandstone.--Its various Soils.

There has been much money lost, and a good deal won, in speculations

connected with the Old Red Sandstone. The speculations in which money

has been won have consorted, if I may so speak, with the character

of the system, and those in which money has been lost have not.

Instead, however, of producing a formal chapter on the economic uses

to which its various deposits have been applied, or the unfortunate

undertakings which an acquaintance with its geology would have

prevented, I shall throw together, as they occur to me, a few simple

facts illustrative of both.

George, first Earl of Cromarty, seems, like his namesake and

contemporary, the too celebrated Sir George M'Kenzie, of Roseavoch,

to have been a man of an eminently active and inquiring mind. He

found leisure, in the course of a very busy life, to write several

historical dissertations of great research, and a very elaborate

_Synopsis Apocalyptica_. He is the author, too, of an exceedingly

curious letter on the "Second Sight," addressed to the philosophic

Boyle, which contains a large amount of amusing and extraordinary

fact; and his description of the formation of a peat-moss in the

central Highlands of Ross-shire has been quoted by almost every

naturalist who, since the days of the sagacious, nobleman, has

written on the formation of peat. His life was extended to extreme

old age; and as his literary ardor remained undiminished till the

last, some of his writings were produced at a period when most other

men are sunk in the incurious indifferency and languor of old age.

And among these later productions are his remarks on peat. He relates

that, when a very young man, he had marked, in passing on a journey

through the central Highlands of Ross-shire, a wood of very ancient

trees, doddered and moss-grown, and evidently passing into a state of

death through the last stages of decay. He had been led by business

into the same district many years after, when in middle life, and

found that the wood had entirely disappeared, and that the heathy

hollow which it had covered was now occupied by a green, stagnant

morass, unvaried in its tame and level extent by either bush or tree.

In his old age he again visited the locality, and saw the green

surface roughened with dingy-colored hollows, and several Highlanders

engaged in it in cutting peat in a stratum several feet in depth.

What he had once seen an aged forest had now become an extensive

peat-moss.

Some time towards the close of the seventeenth century he purchased

the lands of Cromarty, where his turn for minute observation seems

to have anticipated--little, however, to his own profit--some of

the later geological discoveries. There is a deep, wooded ravine in

the neighborhood of the town, traversed by a small stream, which

has laid bare, for the space of about forty yards in the opening

of the hollow, the gray sandstone and stratified clays of the

inferior fish bed. The locality is rather poor in ichthyolites,

though I have found in it, after minute search, a few scales of the

_Osteolepis_, and on one occasion one of the better marked plates of

the _Coccosteus_; but in the vegetable impressions peculiar to the

formation it is very abundant. These are invariably carbonaceous,

and are not unfrequently associated with minute patches of bitumen,

which, in the harder specimens, present a coal-like appearance; and

the vegetable impressions and the bitumen seem to have misled the

sagacious nobleman into the belief that coal might be found on his

new property. He accordingly brought miners from the south, and set

them to bore for coal in the gorge of the ravine. Though there was

probably a register kept of the various strata through which they

passed, it must have long since been lost; but from my acquaintance

with this portion of the formation, as shown in the neighboring

sections, where it lies uplifted against the granitic gneiss of the

Sutors, I think I could pretty nearly restore it. They would first

have had to pass for about thirty feet through the stratified clays

and shales of the ichthyolite bed, with here and there a thin band

of gray sandstone, and here and there a stratum of lime; they would

next have had to penetrate through from eighty to a hundred feet of

coarse red and yellow sandstone, the red greatly predominating. They

would then have entered the great conglomerate, the lowest member of

the formation; and in time, if they continued to urge their fruitless

labors, they would arrive at the primary rock, with its belts of

granite, and its veins and huge masses of hornblende. In short, there

might be some possibility of their penetrating to the central fire,

but none whatever of their ever reaching a vein of coal. From a

curious circumstance, however, they were prevented from ascertaining,

by actual experience, the utter barrenness of the formation.

Directly in the gorge of the ravine, where we may see the partially

wooded banks receding as they ascend from the base to the centre,

and then bellying over from the centre to the summit, there is a

fine chalybeate spring, surmounted by a dome of hewn stone. It was

discovered by the miners when in quest of the mineral which they did

not and could not discover, and forms one of the finest specimens of

a true Artesian well which I have any where seen. They had bored to

a considerable depth, when, on withdrawing the kind of auger used

for the purpose, a bolt of water, which occupied the whole diameter

of the bore, came rushing after, like the jet of a fountain, and

the work was prosecuted no further; for, as steam-engines were not

yet invented, no pit could have been wrought with so large a stream

issuing into it; and as the volume was evidently restricted by the

size of the bore, it was impossible to say how much greater a stream

the source might have supplied. The spring still continues to flow

towards the sea, between its double row of cresses, at the rate of

about a hogshead per minute--a rate considerably diminished, it is

said, from its earlier volume, by some obstruction in the bore.

The waters are not strongly tinctured--a consequence, perhaps, of

their great abundance; but we may see every pebble and stock in

their course enveloped by a ferruginous coagulum, resembling burnt

sienna, that has probably been disengaged from the dark red sandstone

below, which is known to owe its color to the oxide of iron. A Greek

poet would probably have described the incident as the birth of the

Naiad; in the north, however, which, in an earlier age, had also

its Naiads, though, like the fish of the Old Red Sandstone, they

have long since become extinct, the recollection of it is merely

preserved by tradition, as a curious, though by no means poetical

fact, and by the name of the well, which is still known as the well

of the _coal-heugh_--the old Scotch name for a coal-pit. Calderwood

tells us, in his description of a violent tempest which burst out

immediately as his persecutor, James VI., breathed his last, that in

Scotland the sea rose high upon the land, and that many "coal-heughs

were drowned."

There is no science whose value can be adequately estimated by

economists and utilitarians of the lower order. Its true quantities

cannot be represented by arithmetical figures or monetary tables;

for its effects on mind must be as surely taken into account as its

operations on matter, and what it has accomplished for the human

intellect as certainly as what it has done for the comforts of

society or the interests of commerce. Who can attach a marketable

value to the discoveries of Newton? I need hardly refer to the

often-quoted remark of Johnson; the beauty of the language in

which it is couched has rendered patent to all the truth which it

conveys. "Whatever withdraws us from the power of the senses,"

says the moralist--"whatever makes the past, the distant, or the

future, predominate over the present, advances us in the dignity

of thinking beings." And Geology, in a peculiar manner, supplies

to the intellect an exercise of this ennobling character. But

it has, also, its cash value. The time and money squandered in

Great Britain alone in searching for coal in districts where the

well-informed geologist could have at once pronounced the search

hopeless, would much more than cover the expense at which geological

research has been prosecuted throughout the world. There are few

districts in Britain occupied by the secondary deposits, in which,

at one time or another, the attempt has not been made. It has been

the occasion of enormous expenditure in the south of England among

the newer formations, where the coal, if it at all occurs, (for

we occasionally meet with wide gaps in the scale,) must be buried

at an unapproachable depth. It led in Scotland--in the northern

county of Sutherland--to an unprofitable working for many years of

a sulphureous lignite of the inferior Oolite, far above the true

Coal Measures. The attempt I have just been describing was made in

a locality as far beneath them. There is the scene of another and

more modern attempt in the same district, on the shores of the Moray

Frith, in a detached patch of Lias, where a fossilized wood would

no doubt be found in considerable abundance, but no continuous vein

even of lignite. And it is related by Dr. Anderson, of Newburgh,

that a fruitless and expensive search after coal has lately been

instituted in the Old Red Sandstone beds which traverse Strathearn

and the Carse of Gowrie, in the belief that they belong not to

the Old, but to the New Red Sandstone--a formation which has been

successfully perforated in prosecuting a similar search in various

parts of England. All these instances--and there are hundreds

such--show the economic importance of the study of fossils. The

Oolite has its veins of apparent coal on the coast of Yorkshire,

and its still more amply developed veins--one of them nearly four

feet in thickness--on the eastern coast of Sutherlandshire; the

Lias has its coniferous fossils in great abundance, some of them

converted into a lignite which can scarce be distinguished from a

true coal; and the bituminous masses of the Lower Old Red, and its

carbonaceous markings, appear identical, to an unpractised eye, with

the impressions on the carboniferous sandstones, and the bituminous

masses which they, too, are occasionally found to enclose. Nor does

the mineralogical character of its middle beds differ in many cases

from that of the lower members of the New Red Sandstone. I have seen

the older rock in the north of Scotland as strongly saliferous as

any of the newer sandstones, of well nigh as bright a brick-red

tint, of as friable and mouldering a texture, and variegated as

thickly with its specks and streaks of green and buff-color. But

in all these instances there are strongly characterized groups of

fossils, which, like the landmarks of the navigator, or the findings

of his quadrant, establish the true place of the formations to

which they belong. Like the patches of leather, of scarlet, and of

blue, which mark the line attached to the deep-sea lead, they show

the various depths at which we arrive. The Earls of Sutherland set

themselves to establish a coal-work among the chambered univalves

of the Oolite, and a vast abundance of its peculiar bivalves. The

coal-borers who perforated the Lias near Cromarty passed every day

to and from their work over one of the richest deposits of animal

remains in the kingdom--a deposit full of the most characteristic

fossils; and drove their auger through a thousand belemnites and

ammonites of the upper and inferior Lias, and through gryphites and

ichthyodorulites innumerable. The sandstones of Strathearn and the

Carse of Gowrie yield their plates and scales of the _Holoptychius_,

the most abundant fossil of the Upper Old Red; and the shale of the

little dell in which the first Earl of Cromarty set his miners to

work, contains, as I have said, plates of the Coccosteus and scales

of the _Osteolepis_--fossils found only in the Lower Old Red. Nature,

in all these localities, furnished the index, but men lacked the

skill necessary to decipher it.[AU] I may mention that, independently

of their well-marked organisms, there is a simple test through which

the lignites of the newer formations may be distinguished from the

true coal of the carboniferous system. Coal, though ground into an

impalpable powder, retains its deep black color, and may be used as

a black pigment; lignite, on the contrary, when fully levigated,

assumes a reddish, or, rather, umbry hue.

[Footnote AU: There occurs in Mr. Murchison's _Silurian System_ a

singularly amusing account of one of the most unfortunate of all

coal-boring enterprises; the unlucky projector, a Welsh farmer,

having set himself to dig for coal in the lowest member of the

system, at least six formations beneath the only one at which the

object of his search could have been found. Mr. Murchison thus

relates the story:--

"At Tin-y-coed I found a credulous farmer ruining himself in

excavating a horizontal gallery in search of coal, an ignorant miner

being his engineer. The case may serve as a striking example of the

_coal-boring_ mania in districts which cannot by possibility contain

that mineral; and a few words concerning it may, therefore, prove

a salutary warning to those who speculate for coal in the Silurian

Rocks. The farmhouse of Tin-y-coed is situated on the sloping sides

of a hill of trap, which throw off, upon its north-western flank,

thin beds of black grauwacke shale, dipping to the west-north-west at

a high angle. The color of the shale, and of the water that flowed

down its sides, the pyritous veins, and other vulgar symptoms of

coal-bearing strata, had long convinced the farmer that he possessed

a large hidden mass of coal, and, unfortunately, a small fragment

of real anthracite was discovered, which burnt like the best coal.

Miners were sent for, and operations commenced. To sink a shaft was

impracticable, both from the want of means, and the large volume

of water. A slightly inclined gallery was therefore commenced, the

mouth of which was opened at the bottom of the hill, on the side of

the little brook which waters the dell. I have already stated that,

in many cases, where the intrusive trap throws off the shale, the

latter preserves its natural and unaltered condition to within a

certain distance of the trap; and so it was at Tin-y-coed, for the

level proceeded for 155 feet with little or no obstacle. Mounds of

soft black shale attested the rapid progress of the adventurers, when

suddenly they came to a 'change of metal.' They were now approaching

the nucleus of the little ridge; and the rock they encountered was,

as the men informed me, '_as hard as iron_,' viz., of lydianized

schist, precisely analogous to that which is exposed naturally in

ravines where all the phenomena are laid bare. The deluded people,

however, endeavored to penetrate the hardened mass, but the vast

expense of blasting it put a stop to the undertaking, not, however,

without a thorough conviction on the part of the farmer, that, could

he but have got through that hard stuff, he would most surely have

been well recompensed, for it was just thereabouts that they began

to find '_small veins of coal_.' It has been before shown, that

portions of anthracite are not unfrequent in the altered shale,

where it is in contact with the intrusive rock. And the occurrence

of the smallest portion of anthracite is always sufficient to lead

the Radnorshire farmer to suppose that he is very near 'El Dorado.'

Amid all their failures, I never met with an individual who was

really disheartened; a frequent exclamation being, 'O, if our squires

were only men of _spirit_, we should have as fine coal as any in the

world!'"--(_Silurian System_, Part I., p. 328.)]

I have said that the waters of the well of the coal-heugh are

chalybeate--a probable consequence of their infiltration through

the iron oxides of the superior beds of the formation, and their

subsequent passage through the deep red strata of the inferior bed.

There could be very curious chapters written on mineral springs,

in their connection with the formations through which they pass.

Smollett's masterpiece, honest old Matthew Bramble, became thoroughly

disgusted with the Bath waters on discovering that they filtered

through an ancient burying-ground belonging to the Abbey, and that

much of their peculiar taste and odor might probably be owing to

the "rotten bones and mouldering carcasses" through which they were

strained. Some of the springs of the Old Red Sandstone have also the

churchyard taste, but the bones and carcasses through which they

strain are much older than those of the Abbey burying-ground at Bath.

The bitumen of the strongly impregnated rocks and clay-beds of this

formation, like the bitumen of the still more strongly impregnated

limestones and shales of the Lias, seems to have had rather an animal

than vegetable origin. The shales of the Eathie Lias burn like turf

soaked in oil, and yet they hardly contain one per cent, of vegetable

matter. In a single cubic inch, however, I have counted about eighty

molluscous organisms, mostly ammonites, and minute striated scallops;

and the mass, when struck with the hammer, still yields the heavy

odor of animal matter in a state of decay. The lower fish-beds of

the Old Red are, in some localities, scarcely less bituminous.

The fossil scales and plates, which they enclose, burn at the

candle; they contain small cavities filled with a strongly scented,

semi-fluid bitumen, as adhesive as tar, and as inflammable; and for

many square miles together the bed is composed almost exclusively

of a dark-colored, semi-calcareous, semi-aluminous schist, scarcely

less fetid, from the great quantity of this substance which it

contains, than the swine-stones of England. Its vegetable remains

bear but a small proportion to its animal organisms; and from huge

accumulations of these last decomposing amid the mud of a still sea,

little disturbed by tempests or currents, and then suddenly interred

by some widely spread catastrophe, to ferment and consolidate under

vast beds of sand and conglomerate, the bitumen[AV] seems to have

been elaborated. These bituminous schists, largely charged with

sulphuret of iron, run far into the interior, along the flanks

of the gigantic Ben Nevis, and through the exquisitely pastoral

valley of Strathpeffer. The higher hills which rise over the valley

are formed mostly of the great conglomerate--Knockferril, with its

vitrified fort--the wooded and precipitous ridge over Brahan--and

the middle eminences of the gigantic mountain on the north; but

the bottom and the lower slopes of the valley are occupied by the

bituminous and sulphureous schists of the fish-bed, and in these,

largely impregnated with the peculiar ingredients of the formation,

the famous medicinal springs of the Strath have their rise. They

contain, as shown by chemical analysis, the sulphates of soda, of

lime, of magnesia, common salt, and, above all, sulphuretted hydrogen

gas--elements which masses of sea-mud, charged with animal matter,

would yield as readily to the chemist as the medicinal springs of

Strathpeffer. Is it not a curious reflection, that the commercial

greatness of Britain, in the present day, should be closely connected

with the towering and thickly spread forests of arboraceous ferns and

gigantic reeds--vegetables of strange form and uncouth names--which

flourished and decayed on its surface, age after age, during the

vastly extended term of the carboniferous period, ere the mountains

were yet upheaved, and when there was as yet no man to till the

ground? Is it not a reflection equally curious, that the invalids of

the present summer should be drinking health, amid the recesses of

Strathpeffer, from the still more ancient mineral and animal debris

of the lower ocean of the Old Red Sandstone, strangely elaborated

for vast but unreckoned periods in the bowels of the earth? The fact

may remind us of one of the specifics of a now obsolete school of

medicine, which flourished in this country about two centuries ago,

and which included in its _materia medica_ portions of the human

frame. Among these was the flesh of Egyptian mummies, impregnated

with the embalming drugs--the dried muscles and sinews of human

creatures who had walked in the streets of Thebes or of Luxor three

thousand years ago.

[Footnote AV: "In the slaty schists of Seefeld, in the Tyrol,"

say Messrs. Sedgwick and Murchison, "there is such an abundance

of a similar bitumen, that it is largely extracted for medicinal

purposes."--(_Geol. Trans. for 1829_, p. 134.)]

The commoner mineral springs of the formation, as might be

anticipated, from the very general diffusion of the oxide to which it

owes its color, are chalybeate. There are districts in Easter-Ross

and the Black Isle in which the traveller scarcely sees a runnel by

the way-side that is not half choked up by its fox-colored coagulum

of oxide. Two of the most strongly impregnated chalybeates with which

I am acquainted gush out of a sandstone bed, a few yards apart,

among the woods of Tarbat House, on the northern shore of the Frith

of Cromarty. They splash among the pebbles with a half-gurgling,

half-tinkling sound, in a solitary but not unpleasing recess,

darkened by alders and willows; and their waters, after uniting in

the same runnel, form a little, melancholy looking _lochan_, matted

over with weeds, and edged with flags and rushes, and which swarms

in early summer with the young of the frog in its tadpole state, and

in the after months with the black water-beetle and the newt. The

circumstance is a somewhat curious one, as the presence of iron as an

oxide has been held so unfavorable to both animal and vegetable life,

that the supposed poverty of the Old Red Sandstone in fossil remains

has been attributed to its almost universal diffusion at the period

the deposition was taking place. Were the system as poor as has been

alleged, however, it might be questioned, on the strength of a fact

such as this, whether the iron militated so much against the living

existences of the formation, as against the preservation of their

remains when dead.

Some of the springs which issue from the ichthyolite beds along

the shores of the Moray Frith are largely charged, not with iron,

like the well of the coal-heugh, or the springs of Tarbat House,

nor yet with hydrogen and soda, like the spa of Strathpeffer, but

with carbonate of lime. When employed for domestic purposes, they

choke up, in a few years, with a stony deposition, the spouts of

tea-kettles. On a similar principle, they plug up their older

channels, and then burst out in new ones; nor is it uncommon

to find among the cliffs little hollow recesses, long since

divested of their waters by this process, that are still thickly

surrounded by coral-like incrustations of moss and lichens, grass

and nettle-stalks, and roofed with marble-like stalactites. I am

acquainted with at least one of these springs of very considerable

volume, and dedicated of old to an obscure Roman Catholic saint,

whose name it still bears, (St. Bennet,) which presents phenomena

not unworthy the attention of the young geologist. It comes gushing

from out the ichthyolite bed, where the latter extends, in the

neighborhood of Cromarty, along the shores of the Moray Frith;

and after depositing in a stagnant morass an accumulation of a

grayish-colored and partially consolidated travertin, escapes by

two openings to the shore, where it is absorbed among the sand and

gravel. A storm about three years ago swept the beach several feet

beneath its ordinary level, and two little moles of conglomerate

and sandstone, the work of the spring, were found to occupy the two

openings. Each had its fossils--comminuted sea-shells, and stalks

of hardened moss; and in one of the moles I found imbedded a few

of the vertebral joints of a sheep. It was a recent formation on a

small scale, bound together by a calcareous cement furnished by the

fish-beds of the inferior Old Red Sandstone, and composed of sand and

pebbles, mostly from the granitic gneiss of the neighboring hill, and

organisms, vegetable and animal, from both the land and the sea.

The Old Red Sandstone of Scotland has been extensively employed

for the purposes of the architect, and its limestones occasionally

applied to those of the agriculturist. As might be anticipated

in reference to a deposit so widely spread, the quality of both

its sandstones and its lime is found to vary exceedingly in even

the same beds when examined in different localities. Its inferior

conglomerate, for instance, in the neighborhood of Cromarty, weathers

so rapidly, that a fence built of stones furnished by it little more

than half a century ago, has mouldered in some places into a mere

grass-covered mound. The same bed in the neighborhood of Inverness is

composed of a stone nearly as hard and quite as durable as granite,

and which has been employed in paving the streets of the place--a

purpose which it serves as well as any of the igneous or primary

rocks could have done. At Redcastle, on the northern shore of the

Frith of Beauly, the same conglomerate assumes an intermediate

character, and forms, though coarse, an excellent building stone,

which, in some of the older ruins of the district, presents the

marks of the tool as sharply indented as when under the hands of

the workman. Some of the sandstone beds of the system are strongly

saliferous; and these, however coherent they may appear, never resist

the weather until first divested of their salt. The main ichthyolite

bed on the northern shore of the Moray Frith is overlaid by a thick

deposit of a finely-tinted yellow sandstone of this character, which,

unlike most sandstones of a mouldering quality, resists the frosts

and storms of winter, and wastes only when the weather becomes warm

and dry. A few days of sunshine affect it more than whole months of

high winds and showers. The heat crystallizes at the surface the

salt which it contains; the crystals, acting as wedges, throw off

minute particles of the stone; and thus, mechanically at least,

the degrading process is the same as that to which sandstones of a

different but equally inferior quality are exposed during severe

frosts. In the course of years, however, this sandstone, when

employed in building, loses its salt; crust after crust is formed

on the surface, and either forced off by the crystals underneath,

or washed away by the rains; and then the stone ceases to waste,

and gathers on its weathered inequalities a protecting mantle of

lichens.[AW] The most valuable quarries in the Old Red System of

Scotland yet discovered, are the flagstone quarries of Caithness

and Carmylie. The former have been opened in the middle schists of

the lower, or Tilestone formation of the system; the latter, as I

have had occasion to remark oftener than once, in the Cornstone,

or middle formation. The quarries of both Carmylie and Caithness

employ hundreds of workmen, and their flagstones form an article of

commerce. The best building-stone of the north of Scotland--best both

for beauty and durability--is a pure Quartzose Sandstone furnished

by the upper beds of the system. These are extensively quarried in

Moray, near the village of Burghead, and exported to all parts of

the kingdom. The famous obelisk of Forres, so interesting to the

antiquary--which has been described by some writers as formed of a

species of stone unknown in the district, and which, according to a

popular tradition, was transported from the Continent--is evidently

composed of this Quartzose Sandstone, and must have been dug out of

one of the neighboring quarries. And so coherent is its texture, that

the storms of, perhaps, ten centuries have failed to obliterate its

rude but impressive sculptures.

[Footnote AW: When left to time the process is a tedious one, and,

ere its accomplishment, the beauty of the masonry is always in some

degree destroyed. The following passage, from a popular work, points

out a mode by which it might possibly be anticipated, and the waste

of surface prevented:--"A hall of which the walls were constantly

damp, though every means were employed to keep them dry, was about to

be pulled down, when M. Schmithall recommended, as a last resource,

that the walls should be washed with sulphuric acid, (vitriol.)

It w T as done, and the deliquescent salts being decomposed by

acid, the walls dried, and the hall was afterwards free from

dampness."--(_Recreations in Science._)]

The limestones of both the upper and lower formations of the system

have been wrought in Moray with tolerable success. In both, however,

they contain a considerable per centage of siliceous and argillaceous

earth. The system, though occupying an intermediate place between

two metalliferous deposits,--the grauwacke and the carboniferous

limestone,--has not been found to contain workable veins any where

in Britain, and in Scotland no metallic veins of any kind, with the

exception of here and there a few slender threads of ironstone,

and here and there a few detached crystals of galena. Its wealth

consists exclusively in building and paving stone, and in lime. Some

of the richest tracts of corn land in the kingdom rest on the Old

Red Sandstone--the agricultural valley of Strathmore, for instance,

and the fertile plains of Easter-Ross: Caithness has also its deep,

corn-bearing soils, and Moray has been well known for centuries as

the granary of Scotland. But in all these localities the fertility

seems derived rather from an intervening subsoil of tenacious

diluvial clay, than from the rocks of the system. Wherever the clay

is wanting, the soil is barren. In the moor of the Milbuy,--a tract

about fifty square miles in extent, and lying within an hour's walk

of the Friths of Cromarty and Beauly,--a thin covering of soil rests

on the sandstones of the lower formation. And so extreme is the

barrenness of this moor, that notwithstanding the advantages of its

semi-insular situation, it was suffered to lie as an unclaimed common

until about twenty-five years ago, when it was parcelled out among

the neighboring proprietors.

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