Sir Robert Sibbald describes a very remarkable marine whirlpool among the

Orkney islands, which would prove dangerous to strangers, though it is

of no consequence to the people who are used to it. It is not fixed to

any particular place, but arises in various parts of the limits of the

sea among these islands. Wherever it appears, it is very furious, and

boats would inevitably be drawn in and perish with it, but the people

who navigate them are prepared for it and always carry a bundle of straw

or some such matter in the boat with them. This they fling into the

vortex which immediately swallows it up, and, seemingly pleased with

this propitiatory offering, subsides into smoothness, but soon after

re-appears in another place.

A remarkable and sudden rising of the spring-tide takes place at the

mouth of several rivers, for instance, the Indus (where the surprising

phenomenon nearly caused the destruction of the fleet of Alexander the

Great), the Hooghly, the Dordogne, &c. In the Seine it is observed on

a scale of great magnitude. While the tide gradually rises near Havre

and Harfleur, a giant wave is suddenly seen to surge near Quillebœuf,

spanning the whole width of the river (from 30,000 to 36,000 feet).

After this mighty billow has struck against the quay of Quillebœuf, it

enters a more narrow bed and flows stream-upwards with the rapidity

of a race horse, overflowing the banks on both sides, and not seldom

causing considerable loss of property by its unexpected appearance. The

astonishment it causes is increased when it takes place during serene

weather, and without any signs of wind or storm. A deafening noise

announces and accompanies this sudden swelling of the waters, which owes

its first origin to the silent action of gravitation, and is the result

of the diminishing velocity of the tide-wave over a shallow bottom.

While the tide-wave advances over the deep and open seas with an

astonishing rapidity, its progress up the channel of a river is

comparatively very slow, partly on account of the reason just mentioned,

and partly from its meeting a current flowing in an opposite direction.

Thus, the tide takes no less than twelve hours for its progress from the

mouth of the Thames to London, about the time it requires to travel all

the way from Van Diemen's Land to the Cape of Good Hope. Consequently,

when it is high-water at the mouth of the Thames at three o'clock in the

afternoon, for instance, we have not high-water at London Bridge before

three o'clock in the following morning, when it is again high water at

the Nore. But, in the mean time, there has been low water at the Nore

and high water about half-way to London, and while the high water is

proceeding to London, it is ebbing at the intermediate places, and is low

water there when it is high water at London and at the Nore. If the tide

extended as far beyond London as London is from the Nore, we should have

three high waters with two low waters interposed. The most remarkable

instance of this kind is afforded by the gigantic river of the Amazons,

as it appears by the observations of Condamine and others, that, between

Para, at the mouth of the colossal stream, and the conflux of the Madera

and Marañon, there are no less than seven simultaneous high waters with

six low waters between them. Thus, four days after the tide-wave was

first raised in the Southern Ocean, its last undulations expire deep in

the bosom of the South American wilds.

The Mediterranean is generally supposed to be tideless, but this opinion

is erroneous; and in the Adriatic, the flux of the sea is far from being

inconsiderable, for, at Venice, the difference between high and low water

is sometimes no less than six or even nine feet. Mr. W. Trevelyan, during

a summer residence in the old port of Antium, on the Roman coast, found

from a series of accurate observations, that the tides regularly succeed

each other and attain a height of fourteen inches. In the eastern

Mediterranean new measurements have proved that they are still more

considerable, while in the western part of that inclosed sea they are

almost imperceptible.

The differences of level caused by the Mediterranean tides, are indeed

too inconsiderable to attract the general notice of the inhabitants on

the coast, but in the famed Euripus, the narrow channel which separates

the island of Eubœa or Negropont from continental Greece, the tide

produces the striking phenomenon of very irregular fluctuations of the

waters, from one end of the channel to the other.

This phenomenon was of course completely inexplicable to the ancient

philosophers, and Aristotle is even said to have drowned himself in the

Euripus in a fit of despair, since, with all his prodigious sagacity,

he could not possibly solve the mystery. For us, who know that peculiar

formations of the sea-bed and coasts are capable of considerably

augmenting the force of the floods, and that tidal waves rushing into

a narrow channel in opposite directions, and at different times, must

necessarily produce irregular fluctuations of the waters, the phenomenon

of the Euripus has ceased to be a mystery.

CHAP. IV.

MARINE CAVES.

Effects of the Sea on Rocky Shores.--Fingal's Cave.--Beautiful

Lines of Sir Walter Scott.--The Antro di Nettuno.--The Cave

of Hunga.--Legend of its Discovery.--Marine Fountains.--The

Skerries.--The Souffleur in Mauritius.--The Buffadero on the Mexican

Coast.

Whoever has only observed the swelling of the tide on the flat coasts

of the North Sea, has but a faint idea of the Titanic power which it

develops on the rocky shores of the wide ocean. Even in fair weather, the

growing flood, oscillating over the boundless expanse of waters, rises

in tremendous breakers, so that it is impossible to behold their fury

without feeling a conviction that the hardest rock must ultimately be

ground to atoms by such irresistible forces.

Day after day, year after year, they renew their fierce attacks, and

as in the high Alpine valleys the tumultuous torrents rushing from the

glaciers tear deep furrows in the flanks of the mountains, thus it is

here the sea which stamps the seal of its might on the vanquished rocks,

corrodes them into fantastic shapes, scoops out wide portals in their

projecting promontories, and hollows out deep caverns in their bosoms.

Here, also, water appears as the beautifying element, decorating

inanimate nature with picturesque forms, and the sea nowhere exhibits

more romantic scenes than on the rocky shores against which her waves

have been beating for many a millennium. How manifold the shapes into

which the rocky shores are worn! how numberless the changes which each

varying season, nay, every hour of the day with its constant alternations

of ebb and flood, of cloud and sunshine, of storm or calm, produces in

their physiognomy! Our coasts abound in beauties such as these; but

pre-eminent above all other specimens of Ocean's fantastic architecture

is Fingal's Cave, which may well challenge the world to show its equal.

From afar, the small island of Staffa, rising precipitously from the

sea, seems destitute of all romantic interest, but on approaching,

the traveller is struck with the remarkable basaltic columns of which

it is chiefly composed. Most of them rest upon a substratum of solid

shapeless rock, and generally form colonnades upwards of fifty feet high,

following the contours of the inlets or promontories, and overtopped with

smaller hillocks. Along the west coast of the island they are tolerably

irregular, but on the south side Staffa appears as an immense Gothic

edifice, or rather as a forest of gigantic pillars seemingly arranged

with all the regularity of art. The admiration they cause is, however,

soon effaced when the vast cave to which the remote islet owes its

world-wide celebrity bursts upon the view. Fancy a grotto measuring 250

feet in length by 53 in width at the entrance, and spanned by an arch

117 feet high, which, though gradually sloping towards the interior,

still maintains a height of 70 feet at the farthest end of the cavern!

The walls consist of rows of huge hexagonal basaltic pillars, which seem

regularly to diminish according to the rules of perspective. The roof

of the vault is formed of the remnants of similar columns, whose shafts

have beyond a doubt been torn away by the sea, which, destroying them

one after the other, has gradually excavated this magnificent temple of

Nature. All their interstices, like those of the pillars, are cemented

with a kind of pale yellow spar, which brings out all the angles and

sides of their surfaces, and forms a pleasing contrast with the dark

purple colour of the basalt.

The whole floor of the cave is occupied by the sea, the depth of which,

even at its farthest end, is above six feet, during ebb-tide; but

it is only in perfectly calm weather that a boat is able to venture

into the interior, for when the sea is any way turbulent (and this is

generally the case among the stormy Hebrides) it is in danger of being

hurled against the walls of the grot and dashed to pieces. Under these

circumstances, the only access into the cave is by a narrow dyke or ledge

running along its eastern wall, about fifteen feet above the water. It

is formed of truncated basaltic pillars, over which it is necessary to

clamber with great caution and dexterity, as they are always moist and

slippery from the dashing spray. Frequently there is only room enough

for one foot, and while the left hand grasps that of the guide, it is

necessary to hold fast with the right to a pillar of the wall. As this

difficult path is most dangerous in the darkest part of the cave, but

few tourists are bold enough to trust themselves to it, for the least

false step must infallibly precipitate the adventurous explorer into the

seething caldron below. Sometimes a cormorant, fearless of any accident

of this kind, has built his nest upon the top of one of the truncated

pillars, which form the pavement of the pathway, and betrays by a peevish

hissing his ill humour at being disturbed in his solitary retreat by the

intrusion of man.

[Illustration: Fingal's Cave.]

The narrow path ultimately widens into a more roomy and slanting space

formed of the remains of more than a thousand perpendicular truncated

shafts. The back wall consists of a range of unequally sized pillars,

arranged somewhat like the tubes of an organ. When the waves rush with

tumultuous fury into the cave and dash their flakes of snow-white foam

against its wall, it seems as if the gigantic instrument, touched by an

invisible hand, were loudly singing the triumphs of ocean.

Among the beauties of this matchless cave, the clear light must not

be forgotten, which, penetrating through the wide portal, produces an

agreeable chiaro-oscuro even at its farthest end, so that the eye is able

to seize at one glance the full majesty of the splendid hall; nor the

pure air which, constantly renewed by the perpetual alternations of the

tides, is very different from the chilly dampness which generally reigns

in subterranean caverns.

When we consider the resemblance which from its regularity this

magnificent work of nature bears to a production of human art, we cannot

wonder at its having been ascribed to mortal architecture. But as men

of ordinary stature seemed too weak for so colossal an enterprise, it

was attributed to a race of giants, who constructed it for their chief

and leader, Fingal, so renowned in Gaelic mythology. This belief still

lingers among the primitive people of the neighbourhood, though some,

being averse to pagan Goliahs, ascribe its workmanship to St. Columban.

The patriotic muse of Walter Scott, who visited the cave in 1810, rises

to more than ordinary warmth while describing

"That wondrous dome,

Where, as to shame the temples deck`d

By skill of earthly architect,

Nature herself, it seemed, would raise

A minster to her Maker's praise!

Not for a meaner use ascend

Her columns, or her arches bend;

Nor of a theme less solemn, tells

That mighty surge that ebbs and swells,

And still between each awful pause

From the high vault an answer draws

In varied tones, prolonged and high,

That mocks the organ's melody.

Nor doth its entrance front in vain

To old Iona's holy fane,

That Nature's voice might seem to say,

'Well hast thou done, frail child of clay,

Thy humble powers that stately shrine

Task'd high and hard--but witness mine!'"

_Lord of the Isles_, canto iv. stanza 10.

The Mediterranean has likewise its marine grottoes of world-wide

celebrity, its azure cave of Capri,[D] which I have previously described,

and its Antro di Nettuno, in the island of Sardinia, about twelve miles

from the small sea-port of Alghero. Unfortunately this superb grotto is

very difficult of access, for any wind between the north-west and the

south prevents an entry, so that the Algherese assert that 300 out of

the 365 days it is impossible to enter it. The first vaulted cavern,

forming an antechamber about thirty feet high, has no peculiar beauty,

but on crossing a second cavern, in which are about twenty feet of

beautifully clear water, and then turning to the left, one finds oneself

in an intricate navigation among stalactites with surrounding walls and

passages of stalagmites of considerable height. Having passed them and

proceeding westerly, one reaches another cavern with a natural column in

its centre, the shaft and capital of which, supporting the immense and

beautifully fretted roof, reminds one of those in the chapter-house of

the cathedral at Wells, and the staircase of the hall at Christ Church,

Oxford. It stands, the growing monument of centuries, in all its massive

and elegant simplicity with comparatively speaking few other stalagmites

to destroy the effects of its noble solitude. In parts of the grotto

are corridors and galleries, some 300 and 400 feet long, reminding one

of the Moorish architecture of the Alhambra. One of them terminates

abruptly in a deep cavern into which it is impossible to descend; but

among many other interesting objects is a small chamber the access to

which is through a very narrow aperture. After climbing and scrambling

through it, one finds oneself in a room the ceiling of which is entirely

covered with delicate stalactites, and the sides with fretted open work,

so fantastical that one might almost imagine that it was a boudoir of the

Oceanides, where they amused themselves with making lime lace. Some of

the columns in different parts of the grotto are from seventy to eighty

feet in circumference, and the masses of drapery drooping in exquisite

elegance are of equally grand proportions.

[Footnote D: Chap. i. p. 18.]

If a rare chance was required to discover the narrow opening in the

cliffs of Capri, behind which one of the loveliest spectacles of nature

lies concealed, we well may wonder how the famous cave of Hunga in the

Tonga Archipelago ever became known, as its entrance even at low water

is completely hidden under the surface of the sea. Mariner, to whom we

owe our first knowledge of this wonderful play of nature, relates that

while he was one day _rat-hunting_[E] in the island of Hunga with king

Finow, who at that time reigned over Tonga, the barbarian monarch took

a fancy to drink his _kawa_[F] in the cave. Mariner, who had absented

himself for a few moments from the company, was very much astonished

when, returning to the strand, he saw one chieftain after another dive

and disappear. He had but just time to ask the last of them what they

were about. "Follow me," answered the chieftain, "and I will show thee

a place where thou hast never been before, and where Finow and his

chieftains are at present assembled." Mariner immediately guessed that

this must be the celebrated cave of which he had frequently heard, and,

anxious to see it, he immediately followed the diving chieftain, and

swimming close after him under the water, safely reached the opening

in the rock through which he emerged into the cave. On ascending to

the surface, he immediately heard the voices of the company, and still

following his guide, climbed upon a projecting ledge on which he sat

down. All the light of the cave was reflected from the sea beneath,

but yet it was sufficient, as soon as the eye had become accustomed to

the twilight, to distinguish the surrounding objects. A clearer light

being, however, desirable, Mariner once more dived, swam to the strand,

fetched his pistol, poured a good quantity of powder on the pan, wrapped

it carefully up in tapa-cloth and leaves, and, providing himself with

a torch, returned as quickly as possible to the cave. Here he removed

the cloth, a great part of which was still quite dry, and igniting it

by the flame of the powder made use of it to light his torch. This was

probably the very first time since its creation that the cave had ever

been illumined by artificial light. Its chief compartment, which on one

side branched out into two smaller cavities, seemed to be about forty

feet wide and the mean height above the water amounted to as much. The

roof was ornamented in a remarkable manner by stalactites resembling the

arches and fantastic ornaments of a Gothic hall. According to a popular

tradition, the chieftain who first discovered this remarkable cave while

diving after a turtle, used it subsequently as a place of refuge for his

mistress to screen her from the persecutions of the reigning despot.

The sea faithfully guarded his secret: after a few weeks of seclusion,

he fled with his beloved to the Feejee Islands, and on his returning to

his native home after the death of the tyrant, his countrymen heard with

astonishment of the wonderful asylum that had been revealed to him by the

beneficent sea-gods. Lord Byron adopted this graceful tale as the subject

of his poem "The Island, or Christian and his Comrades," and has thus

described the cave, no doubt largely adorning it from the stores of his

brilliant fancy:

"Around she pointed to a spacious cave,

Whose only portal was the keyless wave

(A hollow archway, by the sun unseen,

Save through the billows' glassy veil of green,

On some transparent ocean holiday,

When all the finny people are at play).

"Wide it was and high;

And showed a self-born Gothic canopy.

The arch upreared by Nature's architect,

The architrave some earthquake might erect;

The buttress from some mountain's bosom hurl'd,

When the poles crash'd and water was the world;

Or harden'd from some earth-absorbing fire,

While yet the globe reek'd from its funeral pyre.

The fretted pinnacle, the aisle, the nave,

Were there, all scoop'd by darkness from her cave.

There, with a little tinge of fantasy,

Fantastic faces mopp'd and mow'd on high;

And then a mitre or a shrine would fix

The eye upon its seeming crucifix.

Thus Nature played with the stalactites,

And built herself a chapel of the seas."

[Footnote E: A favourite pastime of the Polynesian chiefs.]

[Footnote F: An intoxicating beverage extracted from the Piper

methysticum, a species of pepper plant.]

On many rocky shores the ocean has worn out subterraneous channels in the

cliffs against which it has been beating for ages, and then frequently

emerges in water-spouts or fountains from the opposite end. Thus, in

the Skerries, one of the Shetland Islands, a deep chasm or inlet, which

is open overhead, is continued under ground and then again opens to

the sky in the middle of the island. When the water is high, the waves

rise up through this aperture like the blowing of a whale in noise and

appearance.

A similar phenomenon is exhibited on the south side of the Mauritius, at

a point called "The Souffleur," or "The Blower." "A large mass of rock,"

says Lieutenant Taylor,[G] "runs out into the sea from the mainland, to

which it is joined by a neck of rock not two feet broad. The constant

beating of the tremendous swell, which rolls in, has undermined it

in every direction, till it has exactly the appearance of a Gothic

building with a number of arches. In the centre of the rock, which is

about thirty-five or forty feet above the sea, the water has forced two

passages vertically upwards, which are worn as smooth and cylindrical as

if cut by a chisel. When a heavy sea rolls in, it of course fills in an

instant the hollow caverns underneath, and finding no other egress, and

being borne in with tremendous violence, it rushes up these chimneys and

flies, roaring furiously, to a height of full sixty feet. The moment the

wave recedes, the vacuum beneath causes the wind to rush into the two

apertures with a loud humming noise, which is heard at a considerable

distance. My companion and I arrived there before high water, and,

having climbed across the neck of rock, we seated ourselves close to the

chimneys, where I proposed making a sketch, and had just begun when in

came a thundering sea, which broke right over the rock itself and drove

us back much alarmed.

"Our negro guide now informed us that we must make haste to recross our

narrow bridge, as the sea would get up as the tide rose. We lost no time

and got back dry enough; and I was obliged to make my sketches from

the mainland. In about three-quarters of an hour the sight was truly

magnificent. I do not exaggerate in the least when I say that the waves

rolled in, long and unbroken, full twenty-five feet high, till, meeting

the headland, they broke clear over it, sending the spray flying over to

the mainland; while from the centre of this mass of foam, the Souffleur

shot up with a noise, which we afterwards heard distinctly between two

and three miles. Standing on the main cliff, more than a hundred feet

above the sea, we were quite wet. All we wanted to complete the picture

was a large ship going ashore."

[Footnote G: Journal of the Royal Geographical Society of London, vol.

iii. 1833.]

THE SOUFFLEUR.

This plate shows the sea beating against some hollow rocks on the

coast of the Mauritius, and producing the remarkable phenomenon called

"The Souffleur," or "The Blower," water-spouts issuing from the

wave-worn cavities of the cliff to a considerable height, and with a

noise distinctly audible at a distance of three miles.

[Illustration: THE SOUFFLEUR ROCK, MAURITIUS.]

A similar phenomenon, on a still more grand and majestic scale, occurs

near Huatulco, a small Mexican village on the coast of the Pacific. On

sailing into the bay one hears a distant noise, which might be taken for

the spouting of a gigantic whale, or the dying groans of a bull struck

by the sharp steel of the matador, or the rolling of thunder. Anxious to

know the cause, "It is the Buffadero," answer the boatmen, pointing to a

fantastically-shaped rock towards which they are rowing. On approaching,

a truly magnificent spectacle reveals itself; for a colossal fountain

springs from an aperture in the rock to a height of 150 feet, and after

having dissolved in myriads of gems, returns to the foaming element

which gave it birth. This beautiful sight renews itself as often as the

breakers rush against the rock, and must be of unequalled splendour when

a tornado sweeps across the ocean and rolls its giant billows into the

hollowed bosom of the cliff.

CHAP. V.

OCEAN CURRENTS.

Causes of the Oceanic Currents.--The Equatorial Stream.--The

Gulf Stream.--Its Influence on the Climate of the West European

Coasts.--The Cold Peruvian Stream.--The Japanese Stream.

Perpetual motion and change is the grand law, to which the whole of the

created universe is subject, and immutable stability is nowhere to be

found, but in the Eternal mind that rules and governs all things. The

stars, which were supposed to be _fixed_ to the canopy of heaven, are

restless wanderers through the illimitable regions of space. The hardest

rocks melt away under the corroding influence of time, for the elements

never cease gnawing at their surface, and dislocating the atoms of which

they are composed. Our body appears to us unchanged since yesterday,

and yet how many of the particles which formed its substance, have

within these few short hours, been cast off and replaced by others. We

fancy ourselves at rest, and yet a torrent of blood, propelled by an

indefatigable heart, is constantly flowing through all our arteries and

veins.

A similar external appearance of tranquillity might deceive the

superficial observer, when sailing over the vast expanse of ocean, at a

time when the winds are asleep, and its surface is unruffled by a wave.

But how great would be his error! For every atom of the boundless sea is

constantly moving and changing its place; from the depth to the surface,

or from the surface to the depth; from the frozen pole to the burning

equator, or from the torrid zone to the arctic ocean; now rising in the

air in the form of invisible vapours, and then again descending upon our

fields in fertilising showers.

The waters are, in fact, the greatest travellers on earth; they know all

the secrets of the submarine world; climb the peaks of inaccessible

mountains, shame the flight of the condor as he towers over the summit

of the Andes, and penetrate deeper into the bowels of the earth than the

miner has ever sunk his shaft.

Leaving their wanderings through the regions of air to the next chapter,

I shall now describe the principal ocean currents, the simple, but

powerful agencies by which they are set in motion, their importance in

the economy of nature, and their influence on the climate of different

countries.

Even in the torrid zone, the waters of the ocean, like a false friend,

are warm merely on the surface, and of an almost icy coldness at

a considerable depth. This low temperature cannot be owing to any

refrigerating influence at the bottom of the sea, as the internal warmth

of the earth increases in proportion to its depth, and the waters of

profound lakes, in a southern climate, never show the same degree of cold

as those of the vast ocean.

The phenomenon can thus only arise from a constant submarine current of

cold water from the poles to the line, and strange as it may seem, its

primary cause is to be sought for in the _warming_ rays of the _sun_,

which, as we all know, distributes heat in a very unequal manner over the

surface of the globe.

Heat expands all liquid bodies, and renders them lighter; cold increases

their weight by condensation. In consequence of this physical law, the

waters of the tropical seas, rendered buoyant by the heat of a vertical

sun, must necessarily rise and spread over the surface of the ocean to

the north and south, whilst colder and heavier streams from the higher

latitudes flow towards the equator along the bottom of the ocean, to

replace them as they ascend.

In this manner, the unequal action of the sun calls forth a general and

constant movement of the waters from the poles to the equator, and from

the equator to the poles; and this perpetual migration is one of the

chief causes by which their purity is maintained. These opposite currents

would necessarily flow direct to the north or south, were they not

deflected from their course by the rotation of the earth, which gradually

gives them a westerly or easterly direction.

The unequal influence of the sun in different parts of the globe, and the

rotation of the earth, are, however, not the only causes by which the

course of ocean-currents is determined.

Violent storms move the waters to a considerable depth, and retard the

flow of rivers, and thus it is to be expected that continuous winds, even

of moderate strength, must have a tendency to impel the waters in the

same direction.

The steady trade-winds of the tropical zone, and the prevailing westerly

winds in higher latitudes, consequently unite their influence with that

of the above mentioned causes, in driving the waters of the tropical seas

to the west, and those of the temperate zones to the east.

The tides also, which on the high seas generally move from east to west,

promote the flow of the ocean in the same direction, and thus contribute

to the westerly current of the tropical seas.

Nor must we forget that the obstacles which the ocean-currents meet on

their way; such as intervening lines of coast, sand banks, submarine

ridges, or mountain chains, have a great influence upon their course, and

may even give them a diametrically opposite direction to that which they

would otherwise have followed.

Having thus briefly mentioned the origin and causes of the currents,

which intersect the seas like huge rivers, I shall now describe such of

them as are most important and interesting in a geographical point of

view.

In the northern part of the Atlantic, between Europe, North Africa, and

the New World, the waters are constantly performing a vast circular or

rotatory movement. Under the tropics they proceed like the trade-winds

from east to west, assisting the progress of the ships that sail from

the Canaries to South America, and rendering navigation in a straight

line from Carthagena de Indias to Cumana (stream upwards) next to

impossible. This westerly current receives a considerable addition from

the _Mozambique_ stream, which, flowing from north to south between

Madagascar and the coast of Caffraria, proceeds round the southern

extremity of Africa, and after rapidly advancing to the north, along the

western coast of that continent, as far as the island of St. Thomas,

unites its waters with those of the equatorial current, and continues its

course right across the Atlantic. In this manner the combined tropical

streams reach the eastern extremity of South America (Cape Roque), where

they divide into two arms. The one flowing to the south follows the

south-eastern coast, and gradually takes a south-easterly direction,

between the tropic of Capricorn and the mouth of the La Plata river,

beyond the limits of the trade-winds. Its traces show themselves to the

south-east of the Cape of Good Hope, and are finally lost far in the

Indian Ocean.

The northern arm of the equatorial stream flows along the north-eastern

coast of South America; constantly raising its temperature under the

influence of a tropical sun, and progressing with a rapidity of a hundred

miles in twenty-four hours (six feet and a half in a second), after

having been joined by the waters of the Amazon river. Thus it continues

to flow to the east, until the continent of Central America opposes

an invincible barrier to its farther progress in this direction, and

compels it to follow the windings of the coast of Costa Rica, Mosquitos,

Campeche, and Tabasco. It then performs a vast circuit along the shores

of the Mexican Gulf, and finally emerges through the Straits of Bahama

into the open ocean.

Here it assumes a new name, and forms what navigators call the

_Gulf-stream_, a rapid current of tepid water, which, flowing in a

diagonal direction, recedes farther and farther from the coast of North

America as it advances to the north-east. Under the forty-first degree

of latitude it suddenly bends to the east, gradually diminishing in

swiftness, and at the same time increasing in width.

Thus it flows across the Atlantic, to the south of the great bank of

Newfoundland, where Humboldt found the temperature of its stream several

degrees higher than that of the neighbouring and tranquil waters, which

form, as it were, the banks of the warm oceanic current. Ere it reaches

the western Azores, it divides into two arms, one of which is driven,

partly by the natural impulse of its stream, but principally by the

prevailing westerly and north-westerly winds, towards the coasts of

Europe; while the other, flowing towards the Canary Islands and the

western coast of Africa, finally returns into the equatorial current.

In this manner the waters are brought back to the point from which they

came, after having performed a vast circuit of 20,000 miles, which it

took them nearly three years to accomplish. According to Humboldt's

calculations, a boat left to the current, and moving along without any

other assistance, would require about thirteen months to float from the

Canary Islands to the Caribbean Sea as far as Caraccas. From Caraccas

to the Straits of Florida, it would remain another ten months on the

way, for though the direct distance is but short, the current has to

perform an enormous circuit of 2500 miles, and flows but slowly in those

confined seas. But the accumulated waters having now to force their

passage through the narrow channel between Cuba and the Bahama Islands on

one side, and Florida on the other, attain so considerable a velocity,

that the whole distance from the Havannah to the Bank of Newfoundland, is

traversed in forty days. During this passage the Gulf-stream particularly

deserves its name, and is easily distinguished from the surrounding

waters by its higher temperature and its vivid dark blue colour. Numerous

marine animals of the tropical seas,--the flying fish, the neat velella,

the purple ianthina, the crosier nautilus, accompany it to latitudes

which otherwise would prove fatal to their existence; and, trusting its

tepid stream, float or swim along to the north or the north-east.

At the extremity of the Bank of Newfoundland, it becomes broader, wavers

more or less in its course, according to the prevailing winds, and at the

same time decreases in rapidity, so that the boat would most likely still

require from ten to eleven months for this last station of its journey,

ere it once more reached the Canary Islands.

The direction of the Gulf-stream explains to us how the productions of

tropical America are so frequently found on the shores of the Eastern

Atlantic. Humboldt relates that the main-mast of the "Tilbury," a ship

of the line, wrecked during the seven years' war on the coast of San

Domingo, was carried by the Gulf-stream to the North of Scotland; and

cites the still more remarkable fact, that casks of palm oil belonging

to the cargo of an English vessel, which foundered on a rock near Cape

Lopez, likewise found their way to Scotland, having thus twice traversed

the wide Atlantic; first borne from east to west by the equatorial

current, and then carried from west to east, between 45° and 55° N.

latitude, by means of the Gulf-stream.

Major Rennell ("Investigation of Currents") relates the peregrinations of

a bottle, thrown overboard from the "Newcastle," on the 20th of January,

1819, in lat. 38° 52′, and long. 66° 20′, and ultimately found on the 2nd

of June, 1820, on the shore of the Island of Arran.

On the 16th of April, 1853, another bottle cast into the waters in the

vicinity of the Bank of Newfoundland, on the 15th of March, 1852, was

found near Bayonne, not far from the mouth of the Adour.

On the coasts of Orcadia, a sort of fruit, commonly known by the name of

_Molucca_, or Orkney beans, are found in large quantities, particularly

after storms of westerly wind.

These beans are the produce of West Indian trees (_Anacardium

occidentale_), and find their way from the woods of Cuba and Jamaica, to

the Ultima Thule of the ancients, by means of the Gulf-stream.

Large quantities of American drift-wood are transported by the same

current to the dreary shores of Iceland,--a welcome gift to the

inhabitants of a region where the highest tree is but a dwarfish shrub,

and cabbages of the size of an apple are raised, as a great rarity, in

the governor's garden.

A short time before Humboldt visited the island of Teneriffe, the sea had

thrown out the trunk of a North American cedar-tree (_Cedrela odorata_),

covered with the mosses and lichens that had grown upon it in the virgin

forest.

The Gulf-stream has even contributed to the discovery of America, for

it is well known that Columbus was strengthened in his belief in the

existence of a western continent, by the stranding on the Azores of

bamboos of an enormous size, of artificially carved pieces of wood, of

trunks of a species of Mexican pine, and of the dead bodies of two men,

whose features, resembling neither those of the inhabitants of Europe nor

of Africa, indicated a hitherto unknown race. But not only lifeless and

inanimate objects find their way across the wide Atlantic by means of

the Gulf-stream and its spreading waters; the living aborigines of the

distant regions of America have also sometimes been driven towards the

coasts of Europe by the combined action of the currents and the winds.

Thus, James Wallace tells us that, in the year 1682, a Greenlander in

his boat was seen by many people near the south point of the island of

Eda, but escaped pursuit. In 1684 another Greenland fisherman appeared

near the island of Wistram. An Esquimaux canoe, which the current and

the storm had cast ashore, is still to be seen in the church of Burra.

In Cardinal Bembo's "History of Venice," it is related that, in the year

1508, a small boat with seven strange-featured men, was captured by a

French vessel in the North Sea. The description given of them corresponds

exactly with the appearance of the Esquimaux; they were of a middle-size,

of a dark colour, and had a broad face with spreading features, marked

with a violet scar. No one understood their language. They were clothed

in seal-skins. They ate raw flesh, and drank blood as we do wine. Six of

these men died on the journey; the seventh, a youth, was presented to the

King of France, who at that time was residing at Orleans.

The appearance of so-called Indians on the coast of the German Sea,

under the Othos and Frederic Barbarossa, or even, as Cornelius Nepos,

Pomponius Melas, and Pliny relate, at the time when Quintus Metellus

Celer was proconsul in Gaul, may be explained by similar effects of the

current and continuous north-easterly winds. A king of the Boians made

a present of the stranded dark-coloured men to Metellus Celer. Gomara,

in his "General History of the Indies," expresses a belief that these

Indians were natives of Labrador, which would be doubly interesting as

the first instance recorded in history of the natives of the Old and the

New World having been brought into contact with each other. We can easily

account for the appearance of Esquimaux on the North European coasts in

former times; as during the eleventh and twelve centuries, their race was

much more numerous than at present, and extended, as we know, from the

researches of Rask and Finn Magnussen, from Labrador to the good Winland,

or the shores of the present State of Massachusetts and Connecticut.

If we compare the climates on the opposite coasts of the Northern

Atlantic, we find a remarkable difference in favour of the Old World.

The frozen regions of Labrador, lie under the same degree of latitude as

Plymouth, where the myrtle and laurel remain perpetually verdant in the

open air. In New York, which has a more southern situation than Rome,

the winter is colder than at Bergen in Norway, which lies 20° farther

to the north. While on the northern coasts of the old continent, the

waters remain open a great part of the year, even beyond the latitude of

80°, the ice never completely thaws on the opposite shores of Greenland.

What a contrast between the Feroë islands, where the harbours are never

frozen, where fertile meadows afford pasturage to numerous flocks of

sheep, and even crops of barley reward the labours of the husbandman,

and the frightful wildernesses on the shores of Hudson's Straits!--and

yet both are situated under the same latitude of 62°.

The milder winter and earlier spring which characterise the north-west

coast of Europe, are due, in some measure, to the prevailing westerly

winds; but there can be no doubt that they are mainly owing to the

influence of the Gulf-stream, which, as we have seen, conveys the heated

waters of the Mexican Gulf far to the north-east, and thus imparts warmth

to the climate of our native isle. In both seas, on the contrary, which

bound the peninsula or island of Greenland, icy currents descend, and

continue their course to the south, along the coasts of North America.

Near Newfoundland their temperature, in May, is found to be 14° lower

than that of the air, and even in spring and the early summer they

carry along with them immense ice-blocks, which are frequently drifted

as far south as the latitude of New York, and finally disappear in the

Gulf-stream.

It is evident that the cold of winter must be increased, and the spring

retarded along the North American coasts by these cold streams, just

as the coasts of Europe are favoured by streams of a contrary nature;

and thus the ocean-currents go a great way to explain the remarkable

differences of climate between the opposite shores of the Northern

Atlantic.

On this occasion I cannot omit directing the reader's attention to the

influence which the far-distant barrier of Central America has upon

the climate of Great Britain. Supposing yon narrow belt of land to be

suddenly whelmed under the ocean, then instead of circuitously winding

round the Gulf of Mexico, the heated waters of the equatorial current

would naturally flow into the Pacific, and the Gulf-stream no longer

exist. We should not only lose the benefit of its warm current, but cold

polar streams, descending farther to the south would take its place,

and be ultimately driven by the westerly winds against our coasts. Our

climate would then resemble that of Newfoundland, and our ports be

blocked up during many months, by enormous masses of ice. Under these

altered circumstances, England would no longer be the grand emporium of

trade and industry, and would finally dwindle down from her imperial

station to an insignificant dependency of some other country more

favoured by Nature.

On examining other coast-lands, in different parts of the globe, we

shall everywhere find the influence of the reigning currents producing

analogous effects to those I have already mentioned.

The Southern Atlantic is not warmed like the European seas by tepid

streams, it is exposed on all sides to the free afflux of the cold waters

of the Antarctic Ocean, and during the summer months to the influence of

drift ice. Thus, the southern extremity of America, Terra del Fuego, the

Falkland Islands, South Georgia, Sandwich Land, and other isles of the

southern ocean, have a much colder climate than the European coasts and

islands situated under the same latitude.

Let us for instance compare the temperature of the Falkland Islands and

of Port Famine in the Straits of Magellan, with that of Dublin, which is

situated at an equal distance from the line.

Mean Temperature.

Latitude. Winter. Summer. Annual.

Dublin 53° 21′ N. +4·0° R. 15·3° 9·6°

Port Famine 53° 38′ S. +0·6 10·0 5·3

Falkland Islands 52° 0′ S. 4·36 11·8 8·24

Feroë Islands 62° 2′ N. 3·9 11·6 7·1

Thus the climate of the Falkland Islands is, as we see, not very

different from that of the Feroë Islands, although the latter lie ten

degrees farther from the equator.

In the Pacific Ocean, as well as in the Atlantic, we find a westerly

current filling the whole breadth of the tropical zone, from the coast of

America to that of Australia and the Indian Archipelago. The best known

of its affluxes is the cold Peruvian stream, which, emerging from the

Polar Sea, flows with great rapidity along the shores of Chili and Peru,

and does not take a westerly direction, before reaching the neighbourhood

of the line. It has everywhere a remarkably low temperature,

comparatively to the latitude, and this sufficiently accounts for the

equal and temperate climate on the coasts of Chili and Peru. Thus, the

mean temperature of Callao (12° S. lat.) is only 20° R. while in Rio

Janeiro (23° S. lat.), though so much farther from the line, the annual

warmth rises to 23·2° R.

In the beginning of November, Humboldt found at Callao the temperature

of the sea within the current not higher than 15·5°, while outside the

stream it rose to 26° or even 28·5° R.

Even in the vicinity of the equator, after the current has already

assumed a westerly direction, its mean temperature does not exceed 20·5°.

But as it advances towards the west, its temperature gradually rises to

27° or 28°.

On the western banks of the Pacific the equatorial stream divides into

several branches. Part of its waters flow to the south, a greater

quantity penetrates through the channels of the south Asiatic Archipelago

into the Indian Ocean, the remainder turns to the north-east, on the

confines of the Chinese Sea, leaves the eastern coast of the Japanese

Islands, and then spreads its warm waters under the influence of

north-westerly winds over the northern part of the Pacific. Thus the

Japanese stream plays here the same part as the Gulf-stream in the

Atlantic, and exerts a similar, though less mighty influence over the

climate of the west coast of America, as it is neither so large nor

so warm, and, having to traverse a wider ocean, in higher latitudes,

naturally loses more of its heat during the passage.

[Illustration: Japan Junks.]

It is owing to this stream that Sitcha enjoys a mean annual temperature

of +7° R., while Nain in Labrador, situated under the same latitude, is

indebted to the Greenland current for a summer of +7·8°, a winter of

-18·5°, and a miserable annual temperature of -3·6°. On the west coast of

North America the analogous trees grow 3° or 4° nearer to the pole, and

the aboriginal tribes go naked as far to the north as 52°, a simplicity

of toilet that would but ill suit the Esquimaux of Labrador.

Besides their beneficial influence on different climates the

ocean-currents tend to equalise, or to maintain the equilibrium of

the saline composition of sea-water, and thus secure the existence

of numberless marine animals. Their movements also contribute to the

formation of sand-banks, where at certain seasons legions of fishes

deposit their spawn and invite the persecutions of man.

The rapidity of currents is very different, but always important enough

to be taken into account by navigators. The well-informed seaman makes

use of them to traverse wide spaces with greater rapidity, and, after

an apparently circuitous course, arrives sooner and more safely at his

journey's end than the ignorant steersman, who vainly endeavours to

strive against their power.

[Illustration: Pavonia lactuca, with Polypes in Natural Position.]

[Illustration: LIGHTHOUSE AND WATER-SPOUTS.]

LIGHTHOUSE AND WATER-SPOUTS.

A Lighthouse on a rocky shore is represented as just lighted, the

twilight having become darkened by a sudden storm, during which the

phenomena of "water-spouts" occur, which are represented to the left

of the Lighthouse.

CHAP. VI.

THE AËRIAL AND TERRESTRIAL MIGRATIONS OF THE WATERS.

Movements of the Waters through Evaporation.--Origin of

Winds.--Trade-Winds.--Calms.--Monsoons.--Typhoons.--Tornadoes.--

Water-Spouts.--The Formation of Atmospherical Precipitations.--Dew.--

Its Origin.--Fog.--Clouds.--Rain.--Snow.--Hail Sources.--The Quantities

of Water which the Rivers pour into the Ocean.--Glaciers and their

Progress.--Icebergs.--Erratic Blocks.--Influence of Forests on the

Formation and Retention of Atmospherical Precipitations.--Consequences

of their excessive Destruction.--The Power of Man over Climate.--How

has it been used as yet?

Neither storms nor ocean-currents, nor ebb and flood, however great

their influence, cause such considerable movements of the waters, or

force them to wander so restlessly from place to place as the silent and

imperceptible action of the warming sunbeam. In every zone evaporation

is constantly active in impregnating the atmosphere with moisture, but

the chief seat of its power is evidently in the equatorial regions, where

the vertical rays of the great parent of light and heat plunge, day after

day, into the bosom of ocean, and perpetually saturate the burning air

with aqueous vapours.

In this chapter I intend following these invisible agents of fertility

and life, as they lightly ascend from the tropical seas, and accompanying

them in their various transformations, until they once more return to the

bosom of their great parent. A cursory view of the benefits they confer

on the vegetable and animal world, as they wander over the surface of the

land, will, I hope, agreeably occupy the reader, and serve to increase

his admiration for that deep and dark blue ocean without which all

organic life would soon be extinct upon earth.

I begin with a few words on the winged carriers of marine exhalations,

the _winds_, which, although now and then detrimental or fatal to

individuals by their violence, largely compensate for these local

injuries, by the constant and inestimable benefits they confer on the

whole body of mankind.

On taking a comprehensive view of their origin, we find that, like the

oceanic currents, they are chiefly caused by the unequal influence of

solar warmth upon the atmosphere under the line and at the poles. In the

torrid zone, the air, rarefied by intense heat, ascends in perpendicular

columns high above the surface of the earth, and there flows off towards

the poles, in the same manner as in a vase filled with cold water and

placed over the flame of a lamp, the warmed liquid rises from the bottom

and spreads over the surface.

But cold air-currents must naturally come flowing in an opposite

direction from the poles to the equator to fill up the void, as in

the example I have cited, colder and consequently heavier water comes

streaming down the sides of the vase to replace the liquid which is

rising in the centre under the influence of heat.

Thus the unequal distribution of solar warmth over the surface of the

earth evidently generates a constant circulation of air from the equator

to the poles, and from the icy regions to the tropics, and by this means

the purity of the atmosphere is chiefly maintained. The sun is not only

the great fountain of warmth, he is also the universal ventilator; he

not only calls forth animal life, but at the same time, by a simple and

admirable mechanism, provides for its health by constantly renewing the

air, which is essential to its existence.

If caloric were the sole agent which influences the direction of the

winds, or if the earth were one uniform plain, the opposite air-currents

I have mentioned would naturally flow straight to the north and south;

but their course is modified or diverted in the same manner as that

of the ocean-currents by the rotation of the globe. Thus, the cold

air-current (polar-stream) which comes rushing upon us from the Arctic

regions, is felt in our latitude as the biting east or north-east wind,

so trying to our nerves and organs of respiration, while we enjoy the

warm air-current from the tropics as the mild western or south-western

breeze.

But besides the rotation of the earth, there are many other local

influences by which the winds are deflected from their course, or by

whose agency partial air-currents are called forth. Among these we

particularly notice high chains of mountains, the unequal capacity of

sea and land in absorbing and retaining heat, which gives rise to sea

and land breezes; the increasing or diminishing power of the sun in

different seasons by which the equilibrium of the air is modified in many

countries, the difference of radiation from a sandy desert or a forest,

electrical discharges from clouds, &c. &c.

Although subject to many of these local disturbances, the winds generally

blow with an astonishing regularity in the tropical zone; while in

our variable climate the polar and equatorial stream are engaged in a

perpetual strife, now bringing us warmth and moisture from the south and

west, now cold and dryness from the north and east.

Thus, in the Atlantic and Pacific Ocean we find the trade-winds

perpetually blowing from the east, the north-east trade-wind between 9°

and 27° N. lat., and the south-east trade-wind between 3° N. lat. and 25°

S. lat. It was by their assistance that Columbus was enabled to discover

America, and that the wretched barks of Magellan traversed the wide

deserts of the Pacific from end to end.

Between these two regions of the trade-winds lies the dreaded zone or

girdle of the equatorial calms (doldrums), where long calms alternate

with dreadful storms, and the sultry air weighs heavily upon the spirits.

"Down dropt the breeze, the sails dropt down,

'Twas sad as sad could be;

And we did speak, only to break

The silence of the sea.

"Day after day, day after day,

We stuck, nor breath, nor motion,

As idle as a painted ship

Upon a painted ocean."

On their polar limits, the trade-wind zones are again girdled with calm

belts, the _horse latitudes_, whose mean breadth is from ten to twelve

degrees. The boundaries of these alternating regions of winds and calms

are not invariably the same, on the contrary, they are perpetually moving

to the north or south, according to the position of the sun.

From 40° N. lat. to the pole, westerly winds begin to be prevalent, and

in the Atlantic Ocean their proportion to the easterly winds is as two to

one.

In the Northern Indian Ocean and in the Chinese Sea we also find the

trade-wind, which is there called the _north-east monsoon_; here,

however, it only blows from October to April, as during the summer

terrestrial influences prevail which completely divert it from its course.

From the wide plains of central Asia glowing with the rays of a

perpetually unclouded sun, the rarefied air rises into the higher

regions. Other columns of air rush from the equator to fill up the

void, and cause the trade-wind to vary its course, and change into the

_south-western monsoons_ of the Indian Ocean, which blow from May to

September. The regularly alternating monsoons materially contributed to

the early development of navigation in the Indian seas, and conducted

the Greeks and Romans as far as Ceylon, Malacca, and the Gulf of Siam.

Similar monsoons, or deflections from the ordinary course of the

trade-winds, occur also in the Mexican Gulf, in the Gulf of Guinea, and

in that part of the Pacific which borders on Central America, through the

influence of the heated plains of Africa, Utah, Texas, and New Mexico.

The passage from one monsoon to the other is of course only gradual,

since the land also is only gradually heated and cooled. Thus at the

change of the monsoon, an atmospheric war of several weeks' continuance

occurs, during which the trade-wind and the monsoon measure their

strength, and calms alternate with dreadful storms (typhoons, cyclones,

tornadoes).

According to the researches and observations of Franklin, Cooper,

Redfield, Reid, &c. &c., these storms are great rotatory winds, that move

along a curved line in increasing circles. In the northern hemisphere,

the rotatory movement follows a direction contrary to that of the hands

of a clock; while the opposite takes place in the southern hemisphere.

The knowledge of the laws which regulate the movements of storms is of

great importance to the mariner, since it points out to him the direction

he has to give his ship to gain the external limits of the tornado, and

thus to remove it from danger.

_Water-spouts_ are formed by two winds blowing in opposite directions,

and raising or sucking up the water in their vortex. They generally form

a double cone; the superior part with its apex downwards, consisting

of a dense cloud, while the inferior cone, the apex of which is turned

upwards, consists of water, which is thus sometimes raised to a height of

several hundred feet.

[Illustration]

[Illustration]

Water-spouts seldom last longer than half-an-hour. Their course and

movements are irregular; straight forwards; in zig-zag lines; alternately

rising and falling; stationary; slow; or progressing with the rapidity

of thirty miles an hour. The rotatory movement is also variable; its

power is often very great, but sometimes water-spouts pass over small

vessels without injuring them. They are more frequent near the coast than

on the high seas; and are more commonly seen in warm climates. They seem

to occur particularly in regions where calms frequently alternate with

storms, which is not to be wondered at, since they owe their origin to

miniature storms or whirlwinds.

[Illustration]

How do the aqueous vapours with which evaporation impregnates the

atmosphere, again descend upon the surface of the earth?

Everybody knows that when in summer a bottle filled with cold water is

brought into the room, it soon gets covered with thick dew-drops, which

presently trickle down its sides, although it was perfectly dry on

entering. Whence does this moisture come from? Not from the inside of

the bottle as ignorant people might imagine, but from the surrounding

atmosphere; in consequence of the capacity of the air to absorb and

retain moisture, increasing or diminishing, as its temperature grows

warmer or colder.

Thus when the cold bottle is introduced into the room, the warm sheet of

air, which is in immediate contact with its surface, immediately cools,

and being no longer able to retain all the moisture with which it was

impregnated, is obliged to deposit it on the sides of the vessel. This

familiar example suffices to explain the formation of dew, rain, hail,

snow, hoar-frost, and all other atmospherical precipitations. They all

result from the influence of some refrigerating cause upon the air; such

as the passage of a warm current into a cooler region; the influx of a

cold wind; a cold-radiating chain of high mountains; a forest, and so

forth.

The very name of dew is refreshing, and calls forth a host of pleasing

ideas, associated as it is with the memory of serene skies and sunny

mornings. How beautiful are its diamonds glittering in all the colours of

the rainbow, on verdant meads, or on the blushing petals of the rose. How

suggestive of all that is lovely, pure, and innocent!

Poetry is of older date than prose, and bards have sung long before

philosophers inquired. Thus, although the children of song from Homer and

Theocritus to Byron and Wordsworth so frequently mention dew in their

immortal strains, it is only in our time that its formation has been

fully explained by Dr. Wells, who in a very ingenious and masterly essay

on this subject, first proved that it results from the ground radiating

or projecting heat into free space, and consequently becoming colder than

the neighbouring air. During calm and clear nights, the upper surfaces of

grass-blades, for instance, radiate their caloric into the serene sky,

from which they receive none in return. The lower parts of the plant,

being slow conductors of heat, can only transmit to them a small portion

of terrestrial warmth, and their temperature consequently falling below

that of the circumambient atmosphere, they condense its aqueous vapours.

Clouds on the contrary compensate for the loss of heat the grass sustains

from radiation, by reflecting or throwing back again upon the terrestrial

surface, the caloric which would else have been dissipated in a clear

sky, and this is the reason why dew does not fall, or but slightly falls

during clouded nights. It is easy to conceive why none is formed in windy

weather, as then the air in contact with the ground is constantly removed

ere it has time to cool so far as to compel it to part with its moisture.

We can also understand why dew is more abundant in autumn and spring than

at any other season; as then very cold nights frequently follow upon warm

days; and why it is most copious in the torrid zone, as in those sultry

regions the air is more saturated with moisture than anywhere else, and

the comparatively cold nights are almost constantly serene and calm.

Hoar-frost is nothing but congealed dew, and owes its formation to the

same causes.

When warmer air-currents are cooled by being transported into colder

regions, or from any other refrigerating cause, a great part of their

moisture generally condenses into small vesicles, but very little heavier

than the surrounding atmosphere, which then becomes visible under the

form of clouds, those great beautifiers of our changing skies, that

frequently trace such picturesque, gorgeous, or singular groups and

landscapes in the aërial regions. The inhabitants of countries where

the heavens are monotonously serene, may well envy us the charms of a

phenomenon which in some measure affords us compensation for so many

disagreeable vicissitudes of the weather. Who that has admired at sunset

the light clouds so beautifully fringed with silver and gold, or glowing

with the richest purple, and loves to follow them in all their wonderful

and fantastic transformations, will deny that they are the poesy and life

of the skies, the awakeners of pleasing fancies and delightful reveries?

Thin wreaths of clouds have been observed, by travellers that have

ascended the most elevated mountains, floating high above the peak of

Chimborazo or Dhawalagiri, and thus shows us to what an amazing altitude

the emanations of ocean are carried by the ascending air-current.

Sometimes when light clouds pass into a warmer atmosphere, they gradually

dissolve and vanish; more frequently the accumulating moisture, too heavy

to continue floating in the air, or condensed by electrical explosions,

descends upon the earth in rain, which, with few exceptions, visits

every part of the globe, either in its liquid form or congealed to snow

or hail. But the quantity of rain which annually falls in different

regions is very unequal, and strange to say, it is not most considerable

in those countries whose climate enjoys an unenviable notoriety for

its clouded atmosphere and the great number of its rainy days. In the

tropical regions it is generally only about the time of the summer

solstice that abundant showers of rain fall regularly every afternoon,

while the rest of the year, the sky is uninterruptedly serene; but during

the short period of the rainy season, a far greater quantity of water is

precipitated upon the earth, than in the temperate zones.

While on the island of Guadaloupe, the annual quantity of rain amounts

to 274·2 French inches, and to 283·3 at Mahabuleshwar, on the western

declivity of the Ghauts, which, as far as has hitherto been ascertained,

is the place where most rain descends; only from 35 to 40 inches fall on

the western coast of England, where the skies are chronically weeping.

It is a remarkable circumstance that the annual quantity of rain which

falls in the same place remains about the same from year to year; so that

by an admirable balancing of conflicting influences, nature seems to

have provided for stability in a province which of all others might be

supposed most open to the caprices of chance.

Having thus followed the exhalations of ocean to the end of what may

be called the first stage of their journey, and seen them descend in a

condensed form upon the surface of the dry land, I will now accompany

them in their ulterior progress to the bosom of the seas. A great part

of them have many transformations and changes to undergo ere they can

accomplish their return; repeatedly rising in vapours from the solid

earth, and falling in showers upon its surface; or circulating through

the tissues of organic life: but after all these intermediate stages and

delays, they ultimately find their way into rivulets or streams, which

after many a meander restore them to the vast reservoir from which they

arose.

The waters that descend upon solid rocks, or fall in large quantities

upon abrupt declivities, immediately flow into the brooks or rivers;

but when they gently and gradually alight upon a porous soil, they are

absorbed by the earth, and, displacing in virtue of capillary attraction,

and of their superior weight, the air which fills the interstices

between its solid particles, sink deeper and deeper until they meet with

a solid and impenetrable stratum. If this forms a hollow basin, they

naturally settle in the cavity; whence they are slowly displaced by fresh

accessions and evaporation; but if its deepest declivity lies somewhere

near the surface, they gradually gush forth under the form of sources

or springs, having unequal distances to perform before they can reach

the orifice. If no fresh supply of water falls, ere the most distant

particles have reached their journey's end, the source dries up: but if

new atmospheric precipitations continually take place, the source is

perennial, although naturally of unequal strength at different times.

The temperature of springs varies from icy coldness to boiling heat. Cold

springs arise when the waters, by which they are fed, descend from high

mountains or do not penetrate a great way into the bowels of the earth;

but if the filtering waters reach a depth which is constantly of a higher

temperature, they then gush forth in the form of warm or even boiling

springs.

A crowd of agreeable associations attaches itself to the idea of sources

and springs, for they are generally both pleasing and useful to man. How

we long in summer for the refreshing waters of the cool fountain issuing

from the mountain side, and murmuring through the woods. The lover of

nature spends hours near some solitary spring, and forgets the flow of

time, as he observes the bubbling and listens to the sweet music of its

crystal waters. A luxuriant vegetation marks their progress, though all

around be burnt up by the scorching sun. Along their margin many a wild

flower blooms, and herbs and shrubs and trees rejoice in a more vivid

green, and statelier growth. There also congregate such members of the

finny race, as delight in cooler streams of untainted purity, and birds

love to build their nests among the sheltering foliage. Thus a little

world forms around the gushing spring, and shows on a diminutive scale,

how all that lives and breathes depends upon the liquid element for its

existence.

While the waters filter through the earth they naturally dissolve a

variety of substances, and all springs are more or less mixed with

extraneous particles. But many of them, particularly such as are of a

higher temperature and consequently arise from deeper strata, contain

either a larger quantity or so peculiar a combination of mineral

substances as to acquire medicinal virtues of the highest order, and to

become objects of importance to a large portion of mankind. Numberless

invalids annually flock to the hygeian fountains which nature unceasingly

pours forth from her mysterious laboratory, and are by them restored to

the enjoyments of a pleasurable existence.

How truly wonderful is the chain of processes which first raises vapours

from the deep, and eventually causes them to gush forth from the entrails

of the earth, laden with blessings and enriched with treasures more

inestimable than those the miner toils for!

Although a river generally has its source in mountainous regions, it

must be remembered that all the waters that descend upon the territory

of which it forms the lowest level, gradually find their way into

its current. Thus, the monarch of all streams, the Amazon River, is

the natural drain of a territory thirty times larger than England.

Thousands of rivulets and brooks, fed by the waters which descend

from the slopes of thousands of glens and valleys, or filter through

the vast forest-plains that rise but a few feet above their surface,

all contribute to swell the majesty of its current. Its sources are

in reality wherever, on that vast extent of land, water descends and

drains into any one of its innumerable affluents. When we hear that on

an average the river of the Amazons alone restores every minute half a

million of tons of water to the ocean, and then consider the countless

number of streams all alike active, that are scattered over the globe,

we may form a faint idea of the vast quantity of vapours which are

constantly rising from the deep, and of the magnitude of these silent

operations of nature. Yet such is the immensity of ocean, that supposing

all the waters it constantly loses, never to return again into its

bosom, it would require thousands of years of evaporation to exhaust the

immensity of its reservoirs!

It might be supposed that the waters which congeal on the sides of

mountains covered with perennial snow, or fill Alpine valleys in the

form of glaciers, were eternally fixed on earth--but there also we are

deceived by delusive appearances of immobility. Every year the glacier

slowly but restlessly makes a step forwards into the valley, and while

its lower end dissolves, new supplies of snow constantly feed it from

above. It has been calculated by Agassiz that the ice masses of the Aar

glacier require 133 years to perform their descent from its summit to

its inferior extremity--a distance of ten miles--so that their sojourn

in that chilled valley far surpasses that of the oldest patriarch of

the mountains. How great must be their delight when they at last are

liberated from the spell which so long enchained them, and freely bound

along on their way to Ocean! How they must shudder at the idea of once

more returning to their desolate prison, and long for the perpetual

warmth of spicy groves and tropical gardens!

In the colder regions of the earth, in Greenland or Spitzbergen, immense

glaciers frequently fill the valleys that open on the sea, descend even

beyond the water's edge, and, as they move along, their overhanging

masses separate from their base and plunge into the deep with a crash

louder than thunder. The icebergs that drift about the Arctic seas,

and are annually conveyed by the currents into lower latitudes, are

formed in this manner. Huge blocks of granite, detached by atmospherical

vicissitudes from the higher mountains and precipitated on the surface

of the glaciers, frequently float on the broad back of an iceberg far

away from the spot where they seemed rooted for eternity. As their

crystal support melts away in its progress to warmer climes, these rocky

fragments, which have been appropriately named _erratic blocks_, fall

to the bottom of the sea hundreds or even thousands of miles from the

starting point of their journey. Thus the great bank of Newfoundland is

covered with stones from distant Greenland, raised high in the air by

volcanic power myriads of years ago, and now condemned to an equally

long repose below the surface of ocean. When will they rise again above

the waters, and what further changes will they have to undergo ere their

compacted atoms resolve themselves into dust and assume new forms? But,

however remote their dissolution, it will inevitably come, for Time is

all-powerful, and has an eternity to work out his changes.

The large blocks of stone that so wonderfully migrate on the wandering

iceberg form but a small and insignificant portion of the terrestrial

spoils which are transported to ocean by the returning waters. Every

river is more or less laden with earthy particles which its current

carries onwards to the sea and deposits at its mouth. In course of time

their accumulation, as I have already mentioned, forms large tracts of

fertile territory encroaching upon the maritime domains.

I shall end with a few words on the influence of forests in attracting

or retaining the atmospherical moisture, as it is a subject of great

importance in the economy of nations, and shows us how much it is in the

power of man to improve or to defeat the provisions of nature in his

favour.

Forests always cool the neighbouring atmosphere, for their foliage offers

an immense warmth-radiating surface, so that the vapours readily condense

above them and descend in frequent showers. At the same time their roots

loosen the soil, and the successive falling of their leaves forms a

thick layer of humus, which has an uncommon power in attracting and

retaining moisture. Their thick canopy of verdure also prevents the rays

of the sun from penetrating to the ground, and absorbing its humidity.

Thus the soil on which forests stand is constantly saturated with water,

and becomes the parent of perennial sources and rills, that spread

fertility and plenty far from the spot where they originated.

The rain-attractive influence of forests did not escape the attention of

Columbus, who ascribed the frequent showers which refreshed and cooled

the air, as he sailed along the coasts of Jamaica, to the vast extent and

density of the woods that covered the mountains of that island. On this

occasion he mentions in his journal that formerly rain had been equally

abundant on Madeira, the Canaries, and the Azores, before their shady

forests were felled or burnt by the improvident settlers.

The wanton destruction of woods has entailed barrenness on countries

renowned in former times for their fertility. The mountains of Greece

were covered with trees during the great epoch of her history, and

the well-watered land bore abundant fruits, and sustained a numerous

population. But man recklessly laid waste the sources of his prosperity.

Along with the woods, many brooks and rivulets disappeared, and ceased

to water the parched plains. The rain gradually washed the vegetable

earth from the sides of the naked hills, and condemned them to sterility.

When the snow of the mountains began to thaw under the warm breath of

spring, it was now no longer retained by the spongy soil of the forests,

and gradually dissolved under their cover; but, rapidly melting, filled

with its impetuous torrents the bed of the rivers, and overflowing their

banks, spread ruin and devastation far around.

Unfortunately, forests when once destroyed are not so easily restored,

and it requires many centuries ere the bared mountain side reassumes

its pristine vesture of shady woods. First lichens, mosses, and other

thrifty herbs, content to feed upon nothing, have to prepare a scanty

humus for the reception of more pretentious guests. In course of time

some small stunted shrub makes its appearance here and there in some

peculiarly favoured spot, and after all requires vast powers of endurance

to maintain itself on the niggard soil, exposed to the full enmity of

wind and weather. This paves the way for a more vigorous and fortunate

offspring; and as every year adds something to the vegetation on the

mountain's side, and opposes increasing obstacles to the winds, the

falling leaves and decaying herbage accumulate more and more, until

dwarfish trees first find a sufficiency of soil to root upon, and

finally, the proud monarch of the forest spreads out his powerful arms

and raises his majestic summit to the skies.

While Greece and Asia Minor have seen their fertility decrease or

vanish with the trees that once covered their hills, other countries

have improved as their vast woods have been thinned by the axe of the

husbandman. In the time of the Romans all Germany formed one vast and

continuous forest, and its climate was consequently much more rigorous

than it is at present. All the low grounds were covered with impervious

morasses, and the winter is described by historians in terms like those

we should employ to paint the cold of Siberia.

But the scene gradually changed as tillage usurped the sylvan domain. The

excessive humidity of the soil diminished, the swamps disappeared, and

the heat of the sea, penetrating into the bosom of the earth, developed

its productive powers. Thus the chestnut and the vine now thrive and

ripen their fruits on the banks of the Rhine and the Danube, where 2000

years ago they could not possibly have existed. But Germany would also

see her fertility decline, if the destruction of the forests which still

crown the brow of many of her hills should continue in a considerable

degree. Numerous rivulets would then be dried up during the warm season,

in consequence of the more rapid descent and thaw of vernal rains and

wintry snows, and most likely, refreshing summer showers would be far

less frequent. Even now the inundations which almost annually desolate

the banks of the Elbe, the Oder, and the Rhine, are ascribed by competent

judges to the excessive clearing of the forests in the mountainous

countries where those rivers originate. These few examples suffice to

prove to us the power of man in modifying the climates of the earth, and

the vast importance of the study of terrestrial physics. By planting

or destroying woods, he is able to compel nature to a more equitable

distribution of her gifts. In marshy and low countries, he may remove

the superfluous waters by drainage, and increase the productiveness of

arid plains by judicious irrigation. Thus man is the lord and master

of the earth; but hitherto he has done but little to reap all the

advantages he might have obtained from his dominion, or even used it

to his own detriment. Drainage, irrigation, and a judicious management

of forest-lands, are only beginning to be understood even among the

most enlightened nations. A great part of our damp island still remains

undrained, and we allow the rivers of India to pour their waters into the

sea, instead of diverting them upon her thirsty plains. But there can be

no doubt that as knowledge increases, man will gradually learn to provide

every soil with the exact measure of humidity that is requisite to make

it bring forth its fruits in the greatest abundance. Views such as these

teach us, that, far from having attained the summit of civilisation,

we are still on the threshold of her temple, and that most likely our

descendants will look down upon our present condition as we do upon that

of our barbarous ancestors.

[Illustration: Rocky Mountains at the bend of Bear Lake River.]

CHAP. VII.

MARINE CONSTRUCTIONS.

Lighthouses.--The Eddystone.--Winstanley's Lighthouse, 1696.--The

Storm of 1703.--Rudyerd's Lighthouse destroyed by Fire in

1755.--Singular Death of one of the Lighthouse Men.--Anecdote of

Louis XIV.--Smeaton.--Bell Rock Lighthouse.--History of the Erection

of Skerryvore Lighthouse.--Illumination Lighthouses.--The Breakwater

at Cherbourg.--Liverpool Docks.--The Tubular Bridge over the Menai

Straits.--The Sub-oceanic Mine of Botallack.

In one of the finest passages of "Childe Harold," Byron contrasts the

gigantic power of the sea with the weakness of man. He describes the

resistless billows contemptuously playing with the impotent mariner--now

heaving him to the skies, now whelming him deep in the bosom of the

tumultuous waters; he mocks the vain pride of our armadas, which are but

the playthings of ocean, and points with a bitter sneer at the wrecks

with which he strews his shores. A less misanthropic mood or a more

truthful view of things might have prompted the wayward poet to celebrate

the triumphs of man over the brute strength of the winds and waves; how,

guided by the compass, he boldly steers through the vast waste of waters,

how he excavates the artificial harbour, or piles up the breakwater to

protect his bark against the destructive agencies of the billow and the

storm, or how he erects the lighthouse to point out the neighbourhood of

dangerous shoals or the entrance of the friendly port.

The various constructions planned and executed by man to disarm the

turbulent or perfidious seas of a great part of their terrors, are indeed

among the noblest monuments of his architectural genius, nor are any more

deserving of universal applause and gratitude. Who has ever performed a

winter voyage homewards over the wide Atlantic and not felt a thrill of

delight when the first bright flash of light beamed over the dark waters

and welcomed him back to his native isle? or what generous mind has ever

experienced this feeling without devoting the tribute of its thanks to

the wise and beneficent men whose energy and perseverance have succeeded

in lighting every headland or estuary of our rugged coast? So completely

has this been done, that in the dark and stormy night, almost as well as

in the brightest day, the homeward-bound ship need not approach danger

without receiving friendly warning, for her pathway is illuminated by

gigantic fire-beacons so thickly set that when one fades to the sight a

new one rises to the view.

Among the numerous lighthouses with which the genius of humanity has

encircled our native shores, the Eddystone, the Bell Rock, and the

Skerryvore, are pre-eminent for the vast difficulties that had to be

surmounted in their construction, situated as they are upon solitary

rocks, exposed to the full fury of the insurgent waves; and should by

some revolution all other monuments erected by man be swept away from

the surface of our land, and these alone remain, they would suffice

to testify to future ages that these islands were once inhabited by a

highly civilised and energetic race, one well worthy to lay claim to the

dominion of the seas.

At the distance of about twelve miles and a half from Plymouth Sound,

and intercepting, as it were, the entrance of the Channel, the

Eddystone rocks had been for ages a perpetual menace to the mariner.

The number of vessels wrecked on these perfidious shoals must have been

terrible indeed, it being even now a common thing in foggy weather for

homeward-bound ships to make the Eddystone Lighthouse as the first

point of land of Great Britain, so that in the night and nearly at high

water, when the whole range of the rocks is covered, the most careful

pilot might run his ship upon them, if nothing was placed there by way

of warning. As the trade of England increased, the number of fatal

accidents naturally augmented, rendering it more and more desirable to

crest the Eddystone with a tutelary beacon; yet years elapsed before

an architect appeared bold enough to undertake the task. At length, in

1696, Mr. Winstanley, a country gentleman and amateur engineer, made the

first attempt of raising a lighthouse on those sea-beaten rocks, but as

he was possessed of more enterprise than solid knowledge, the structure

he erected was deficient in every element of stability. Yet such was

the presumption of the man that he was known to express a wish that

the fiercest storm that ever blew might arise to test the solidity of

the fabric. The elements took him at his word, for while on a visit of

inspection to his lighthouse the dreadful storm of November 26, 1703,

arose, the only storm which in our latitude has equalled the rage of

a tropical hurricane. "No other tempest," says Macaulay in his Essay

on Addison, "was ever in this country the occasion of a Parliamentary

address or of a public fast. Whole fleets had been cast away. Large

mansions had been blown down. One Prelate had been buried beneath the

ruins of his palace. London and Bristol had presented the appearance of

cities just sacked. Hundreds of families were still in mourning. The

prostrate trunks of large trees and the ruins of houses still attested

in all the southern counties the fury of the blast." No wonder that a

tempest like this swept away the ill-constructed lighthouse like the

"unsubstantial fabric of a vision," and that neither poor Mr. Winstanley

nor any of his companions survived to recount the terrors of that

dreadful night.

Strange to say, the task of rebuilding the Eddystone lighthouse, which

was now felt as a national necessity, once more devolved, not upon a

professed architect, but upon a Mr. Rudyerd, a linendraper of Ludgate

Hill, the son of a Cornish vagrant, who had raised himself by his

talents and industry from rags and mendicancy to a station of honourable

competence. The choice, however, was not ill made, for, with the

assistance of two competent shipwrights, the London tradesman constructed

an edifice which, though mainly of timber, was so firmly bolted to the

rock with iron branches that for nearly half a century it resisted the

fury of the billows, and might have withstood them for many a year to

come had it not been rapidly and completely destroyed by fire. This

catastrophe, which happened on December 2, 1755, was marked by a strange

accident, for while one of the light-keepers was engaged in throwing up

water four yards higher than himself, a quantity of lead, dissolved by

the heat of the flames, suddenly rushed like a torrent from the roof,

and falling upon his head, face, and shoulders, burnt him in a dreadful

manner. Having been conveyed to the hospital at Plymouth, he invariably

told the surgeon who attended him, that he had swallowed part of the

lead while looking upward; the reality of the assertion seemed quite

incredible, for who could suppose it possible that any human being could

exist after receiving melted lead into the stomach, much less that he

should afterwards be able to bear the hardships and inconvenience from

the length of time he was in getting on shore before any remedies could

be applied. On the twelfth day, however, the man died, and having been

opened a solid piece of lead, which weighed above seven ounces, was found

in his stomach.[H]

[Footnote H: A full account of this extraordinary circumstance was sent

to the Royal Society, and printed in vol. xlix. of their Transactions, p.

477.]

Another interesting anecdote is attached to the history of Rudyerd's

lighthouse. Louis XIV. being at war with England while it was being

built, a French privateer took the men at work upon it and carried them

to France, expecting, no doubt, a good reward for the achievement. His

hopes, however, were doomed to a grievous disappointment, for while the

captives lay in prison, the transaction reached the ears of the monarch,

who immediately ordered them to be released and the captors to be put in

their place; declaring that though he was at war with England, he was not

at war with mankind. He therefore directed the men to be sent back to

their work with presents; observing that the Eddystone lighthouse was so

situated as to be of equal service to all nations navigating the Channel.

It is gratifying to meet with this trait of natural generosity in a mind

long since obscured by the bigotry which prompted the revocation of the

Edit de Nantes.

[Illustration: Eddystone Lighthouse.]

After these repeated disasters, the rebuilding of Eddystone lighthouse,

in a more substantial manner than had hitherto been effected, was now no

longer confided to amateur ingenuity, but to John Smeaton, an eminent

civil engineer, one of those men who by originality of genius and

strength of character are so well entitled to rank among the worthies of

England. From his early infancy Smeaton (born May 28, 1724) gave tokens

of the extraordinary abilities which were one day to render his name

illustrious. Before he attained his sixth year his playthings were not

the playthings of children but the tools which men employ: before he

was fifteen he made for himself an engine for turning, forged his iron

and steel, and had self-made tools of every sort for working in wood,

ivory, and metals. At eighteen he by the strength of his genius acquired

the art of working in most of the mechanical trades, and such was his

untiring zeal that a part of every day was generally occupied in forming

some ingenious piece of mechanism. In 1753, his various inventions and

improvements had already attracted such notice that he was elected member

of the Royal Society; and when, a few years later, the accident happened

which burnt down the Eddystone lighthouse to the ground, he was at once

fixed upon as the person most proper to rebuild it. A better choice

could not possibly have been made, for Smeaton's lighthouse, firm as

the rock on which it stands, has now already braved the storms of more

than a century, and will no doubt continue to brave them for many ages

to come. Of him it may well be said "exegit monumentum ære perennius,"

for to him is due the honour of having fixed the _best form_ to be given

to a marine lighthouse, and even now the Eddystone beacon-tower remains

a model which has hardly been surpassed by the taller and more graceful

edifices of Bell Rock and Skerryvore. Nothing could exceed the patient

ingenuity, the sagacity, and forethought with which that great engineer

mortised his tall tower to the wave-worn rock, and then dove-tailed the

whole together, so as to make rock and tower practically one stone, and

that of the very best form for deadening the action of the wave. Nor must

we forget that our great marine lighthouses, of which Smeaton gave the

model, are as remarkable from an artistic as from a utilitarian point

of view, as pleasing to the man of taste as to the friend of humanity.

"It is to be regretted," says, with perfect justice, the author of an

excellent article in the Quarterly Review,[I] "that these structures are

placed so far at sea that they are very little seen, for they are, taken

altogether, perhaps the most perfect specimens of modern architecture

which exist. Tall and graceful as the minar of an Eastern mosque, they

possess far more solidity and beauty of construction; and, in addition

to this, their form is as appropriate to the purposes for which it was

designed as anything ever done by the Greeks, and consequently meets

the requirements of good architecture quite as much as a column of the

Parthenon."

[Footnote I: No. 228.]

Covered to the height of fifteen feet at spring tide, and little more

than a hundred yards in its extent, the famous Bell Rock, or Inchcape,

facing the Frith of Tay at a distance of twelve miles at sea, was as

dangerous to the navigation of the eastern coast of Scotland as the

Eddystone had been to the entrance of the Channel. To erect a tower on a

spot like this was an undertaking of no common boldness, but, fired by

Smeaton's example, Mr. Robert Stevenson no less gloriously succeeded in

converting what for ages had been a source of danger into a beacon of

safety.

[Illustration: Bell Rock Lighthouse.]

On the opposite coast of Scotland, and placed in the same parallel of

latitude as Bell Rock, the Skerryvore Reef had a name equally dreaded by

the mariner. Situated considerably farther from the mainland than the

Bell Rock, it is less entirely submerged, some of its summits rising

above the level of high water, though the surf dashes over them; but the

extent of foul ground is much greater, and hidden dangers, even in fine

weather, beset the intervening passage between its eastern extremity

and Tyree, from which island it is distant some eleven miles. In rough

weather the sea which rises there is described as one in which no ship

could live. This terrible reef, so fatal to many a gallant bark, rendered

the erection of a lighthouse most desirable, yet such was the difficulty

of the case that although so long ago as 1814 an Act was obtained for

a light on Skerryvore, it was not before 1837 that Mr. Alan Stevenson,

son of the famous architect of the Bell Rock sea-tower, was authorised

to commence the work. That difficulty was not confined to the position

and character of the reef itself, as the neighbouring island of Tyree

afforded no resource, and all the materials for the building, even the

stone itself, had to be transported from distant quarters. At length, all

preliminary arrangements being settled, the engineer reached the rock

and commenced his work, in June 1838, by erecting a barrack-house upon

stilts--a sort of dovecot perched on poles--high out of the water on the

reef, close to the proposed site of the lighthouse. The erection of this

barrack fully occupied the first summer; and, lest it might be supposed

that this was but little work for so long a time, it may be as well to

remark that, such was the turbulence of the sea that between August 7

and September 11, it had only been possible to be 165 hours on the rock.

Much inconvenience was occasioned by the hard and slippery nature of the

volcanic formation of the Skerryvore, to which the action of the sea had

given the appearance and the smoothness of a mass of dark-coloured glass,

so that the foreman of the masons compared the operation of landing on it

to that of climbing up the neck of a bottle. When we consider how often,

by how many persons, and under what circumstances of swell and motion,

this operation was repeated, we must look upon this feature of the spot

as an obstacle of no slight amount.

At length, after much danger and difficulty, the barrack was completed,

but the first November storm swept it away and utterly annihilated the

work of the season. Iron stancheons had been drawn, broken, and twisted

like the wires of a champagne bottle; the smith's iron anvil had been

transported eight yards from where it was left; and a stone three-fourths

of a ton was lifted out from the bottom of a hole and sent towards the

top of the rock.

Mortified, but nothing daunted by this disaster, which gave him a warning

of the tremendous power he had to contend with, Mr. Stevenson prepared

during the winter for the labours of 1839, which, besides the re-erection

of the barrack on an improved plan, chiefly consisted in the levelling or

blasting of a flat surface of forty-two feet diameter on the top of the

rock from which the lighthouse was to arise. This foundation pit was in

itself a work of no small magnitude, as it required for its excavation

the labours of 20 men for 217 days, the firing of 296 shots, and the

removal into deep water of 2,000 tons of material. The blasting, from

the absence of all cover and the impossibility of retiring to a distance

farther in any case than thirty feet, and often reduced to twelve,

demanded all possible carefulness.

The only precautions available were a skilful appointment of the charge

and the covering the mines with mats and coarse netting made of old rope.

Every charge was fired by or with the assistance of the architect in

person, and no mischief occurred.

The year 1840 had now arrived, and the construction of the lighthouse

was about to begin. Quarriers and labourers had been busily employed

in cutting blocks of stone in the quarries. Carpenters were diligently

engaged in making wooden moulds for each lighthouse block wherewith

to gauge its exact mathematical figure. In April, a reinforcement of

thirty-seven masons from Aberdeen arrived at Tyree--men expert in the

difficult work of dressing granite--and, on April 30, the first visit was

made to the rock. To the great joy of all, the barrack constructed in

the previous season was found uninjured, though a mass of rock weighing

about five tons had been detached from its bed and carried right across

the foundation pit by the violence of the waves. In this barrack the

architect and his party now took up their quarters, which from the

frequent flooding of the apartments with water and from the heavy spray

that washed the walls were anything but agreeable. "Once," says the

gallant engineer,[J] "we were fourteen days without communication with

the shore or the steamer, and during the greater part of that time we

saw nothing but white fields of foam as far as the eye could reach;

and heard nothing but the whistling of the wind and the thunder of the

waves, which was at times so loud as to make it almost impossible to

hear anyone speak. Such a scene, with the ruins of the former barrack

not twenty yards from us, was calculated to inspire the most desponding

anticipations; and I well remember the undefined sense of dread that

flashed on my mind, on being awakened one night by a heavy sea which

struck the barrack and made my cot swing inwards from the wall, and was

immediately followed by a cry of terror from the men in the apartment

above me, most of whom, startled by the _sound and the tremor_, sprang

from their berths to the floor, impressed with the idea that the whole

fabric had been washed into the sea."

[Footnote J: Account of Skerryvore Lighthouse, by Alan Stevenson,

Engineer to the Northern Lighthouse Board. Edinburgh, 1848.]

This spell of bad weather, though in summer, well-nigh outlasted their

provisions; and when at length they were able to make the signal that a

landing would be practicable, scarcely twenty-four hours' stock remained

on the rock. The landing of the heavy stones from the lighters was a work

of no small difficulty, considering the slippery nature of the rock,

and as the loss of one dressed stone would frequently have delayed the

whole progress of the building, the anxiety was incessant. On July 4, the

building of the tower really commenced. Six courses of masonry carried

the building to the height of 8 feet 2 inches before the autumnal gales

terminated the work of 1840, and an excellent year's work it was. The

saying that "what is well begun is half done" was illustrated here. Next

year's work was comparatively easy--so that in 1842 the tower rose to its

full height of 138 feet; and the year after the light was shedding its

beneficent rays over the thirty miles of watery waste that surround the

hidden rocks of Skerryvore.

[Illustration: The Skerryvore Lighthouse.]

Well may we be proud of men like Smeaton and the Stevensons; but, while

justly admiring their architectural skill, their perseverance, and their

courage, we must not forget to offer the just tribute of our gratitude

to the eminent natural philosophers without whose ingenious optical

inventions the most splendid sea-towers would be comparatively useless.

The Pharus or lighthouse of Alexandria was, probably with justice,

reckoned among the seven wonders of the world, and its several stories,

rising on marble columns to the height of 400 feet, must have presented

an imposing spectacle, but I strongly suspect that the rude brazier

on the summit of the majestic pile bore the same proportion to the

lighthouse lanterns of our time as the wretched coasting-craft of the

ancient Greeks to the ocean steamers of the present day. Among the names

of those who have contributed most effectually to the progress of marine

illumination Argand, Borda, and Fresnel are conspicuous. The hollow

cylindrical wick of the first was a sudden and immense advance in the art

of economical and effective illumination. The second, by his invention

of the parabolic mirror, multiplied the effect of the unassisted flame

by 450, and the refracting lens of Fresnel so admirably concentrates the

light as to project its warning beams to the wonderful distance of thirty

or thirty-five miles.

In former ages the efforts of man to provide a refuge to the mariner

from the fury of the raging gale were feeble and insignificant. Content

with the harbours that nature had provided, it was then thought quite

sufficient to line a river-bank with quays or to enclose a natural pond

by walls. The idea of raising colossal breakwaters by casting whole

quarries into the deep, or of extending artificial promontories far

into the bosom of the ocean, is of modern date, and would have appeared

chimerical not only to the ancients but to our fathers not a century ago.

The first great work of this description is the famous breakwater planned

by De Cessart in 1783, and terminated in 1853, which has converted the

open roadstead of Cherbourg into a land-locked harbour. Rising from a

depth of 40 feet at low spring tides, on a coast where the floods attain

a height of 19 feet, it opposes a front of 12,700 feet to the fury of the

storm, and carries 250 pieces of the heaviest cannon on its formidable

brow.

It far surpasses in extent and boldness of construction the breakwater at

Plymouth, nor will it be eclipsed by the moles now forming at Portland,

Holyhead, and Alderney; but although it is a more impressive spectacle to

see man struggling with the ocean and producing calmness and shelter in

the midst of the raging storm, than to contemplate his operations where

he has no such adversaries to subdue, still such buildings as those just

described are neither the largest nor the most expensive works required

for the accommodation of shipping. Witness the Cyclopean grandeur of the

Liverpool docks or of the Great Float at Birkenhead, which alone covers

an area of water of 121 acres, and whose portals, with a clear opening

of 100 feet, will admit the largest screw-steamer or sailing ship the

wildest imagination has yet conceived. Six millions of money is the cost

of this one work alone--more than would be required to raise a pyramid

like that of Cheops--and even this sum is a trifle when compared with

what has been spent on the harbours of Liverpool, London, and other great

commercial cities.

Not satisfied with erecting his lighthouses on wave-worn rocks or defying

the waves with his colossal breakwaters, man spans bridges over arms of

the sea and excavates mines under the abysses of the deep. The locomotive

now rolls full speed 100 feet above high water over the strait which

separates Anglesea from the mainland; and in Botallack and several other

Cornish mines the workman, while resting from his subterranean labours,

hears the awful voice of the ocean rolling over his head.

"In all these submarine mines," says Mr. Henwood, "I have heard the

dashing of the billows and the grating of the shingle when in calm

weather. I was once, however, underground in Wheal Cock during a storm.

At the extremity of the level seaward some eighty or one hundred

fathoms from the shore, little could be heard of its effects, except

at intervals, when the reflux of some unusually large wave projected a

pebble outward, bounding and rolling over the rocky bottom. But when

standing beneath the base of the cliff, and in that part of the mine

where but nine feet of rock stood between us and the ocean, the heavy

roll of the large boulders, the ceaseless grinding of the pebbles, the

fierce thundering of the billows, with the crackling and boiling as they

rebounded, placed a tempest in its most appalling form too vividly before

me ever to be forgotten. More than once doubting the protection of our

rocky shield, we retreated in affright, and it was only after repeated

trials that we had confidence to pursue our investigations." Yet the

miners, accustomed from their early youth to the fierce and threatening

roaring of the stormy sea, pursue their work from year to year, never

doubting that the thin roof which separates them from a watery grave will

continue to protect them, as it has shielded their fathers before them.

PART II.

THE INHABITANTS OF THE SEA.

CHAP. VIII.

THE CETACEANS.

General Remarks on the Organisation of the Cetaceans.--The Large

Greenland Whale.--His Food and Enemies.--The Fin-Back or Rorqual.--The

Antarctic Whale.--The Sperm-Whale.--The Unicorn Fish.--The

Dolphin.--Truth and Fable.--The Porpoise.--The Grampus.--History of

the Whale Fishery.

Of all the living creatures that people the immensity of ocean, the

cetaceans, or the whale family, are the most perfect. Their anatomical

construction renders them in many respects similar to man, and their

heart is susceptible of a warmth of feeling unknown to the cold-blooded

fishes; for the mother shows signs of attachment to her young, and

forgets her own safety when some danger menaces her offspring. Like

man, the cetaceans breathe through lungs, and possess a double heart,

receiving and propelling streams of _warm_ red blood. The anatomical

structure of their pectoral fins bears great resemblance to that of the

human arm, as the bony structure of those organs equally consists of a

shoulder-blade, an upper arm, a radius and ulna, and five fingers.

But the arm, which in man moves freely, is here chained to the body as

far as the hand, and the latter, which, in obedience to human volition

and intellect, executes such miracles of industry and art, is here

covered with a thick skin, and appears as a broad undivided fin or

flapper. Yet still it is destined for higher service than that of a mere

propelling oar, as it serves the mother to guide and shield her young.

The lower extremities are of course wanting, but their functions are

performed by the mighty _horizontal_ tail, by whose powerful strokes the

unwieldy animal glides rapidly through the waters.

The cetaceans distinguish themselves, moreover, from the fishes by the

bringing forth of living young, by a greater quantity of blood, by the

smoothness of their skin, under which is found a thick layer of fat, and

by their simple or double blow-hole, which is situated at the top of the

head, and corresponds to the nostrils of the quadrupeds, though not for

the purpose of smelling, but merely as an organ of respiration.

[Illustration: Bones of the Anterior Fin of a Whale.]

Our knowledge of the cetaceans is still very incomplete; and this is not

to be wondered at, when we consider that they chiefly dwell in the most

inaccessible parts of the ocean, and that when met with, the swiftness

of their movements rarely allows more than a flighty view of their

external form. Thus their habits and mode of living are mostly enveloped

in obscurity; and while doubtless many cetaceans are to the present day

unknown, one and the same species has not seldom been described under

different names, to the no small confusion of the naturalist.

The cetaceans are either without a dental apparatus, or provided with

teeth. The former, or the whalebone whales, have two blow-holes on the

top of the head, in the form of two longitudinal fissures; while in the

latter, (sperm-whales, unicorn-fish, dolphins,) which comprise by far

the greater number of species, there is but one transversal spout-hole.

In all whales the larynx is continued to the spouting canal, and deeply

inserted or closely imbricated within its tube. Thus no tones approaching

to a voice can be emitted except through the spiracles, which are

encumbered with valves, and evidently badly adapted for the transmission

of sound. Scoresby assures us that the Greenland whale has no voice, and

Bennett frequently noticed sperm-whales suffering from extreme alarm

and injury, but never heard any sound from them beyond that attending an

ordinary respiration.

The whalebone whales are either _smooth-backs_ (Balænæ), or _fin-backs_

(Balænopteræ), having a vertical fin rising from the lower part of

the back. To the former belongs the mighty Greenland Whale (_Balæna

mysticetus_), the most bulky of living animals, and of all cetaceans

the most useful and important to man. Its greatest length, according to

Scoresby, is from sixty to seventy feet, and round the thickest part

of its body it measures from thirty to forty feet, but the incessant

persecutions to which it is subjected scarcely ever allow it to attain

its full growth.

The whale being somewhat lighter than the medium in which it swims,

its weight may be ascertained with tolerable accuracy; and Scoresby

tells us that a stout animal of sixty feet weighs about seventy tons,

allowing thirty to the blubber, eight or ten to the bones, and thirty

or thirty-two to the carcase. The lightness of the whale, which enables

it to keep its _crown_, in which the blow-hole is situated, and a

considerable extent of back above the water, without any effort or

motion, is not only owing to its prodigious case of fat, but also to the

lightness of its bones, most of which are very porous and contain large

quantities of fine oil; an admirable provision of nature for the wants of

a creature destined to breathe the atmospheric air, and to skim its food

from the surface of the waters.

The unsightly animal shows disproportion in all its organs. While

the tail fin measures twenty-four feet across, the pectoral fins or

paddles are no more than six feet long. The monstrous head forms

about the third of the whole body, and is furnished with an equally

monstrous mouth, which on opening exhibits a cavity about the size of

an ordinary ship's cabin. The leviathans of the dry land, the elephant,

the rhinoceros, and the hippopotamus, are provided with tusks and teeth

corresponding to their size--huge weapons fit for eradicating trees or

crushing the bone-harnessed crocodile; but the masticatory implements

of the giant of the seas are scarcely capable of dividing the smallest

food. Instead of teeth, its enormous upper jaw is beset with about 500

laminæ of whalebone, ranged side by side, two-thirds of an inch apart,

the thickness of blade included, and resembling a frame of saws in

a saw-mill. Their interior edges are covered with fringes of hair;

externally they are curved and flattened down, so as to present a smooth

surface to the lips. The largest laminæ, situated on both sides of the

jaw, attain a length of fifteen feet, and measure from twelve to fifteen

inches at their base; in front and towards the back of the mouth they are

much shorter.

[Illustration: Skull of Whale, with the Baleen.]

Besides these, there are suspended from the palate many other small

laminæ of the thickness of a quill, a few inches long, and likewise

terminating in a fringe. Thus the whole roof of the mouth resembles a

shaggy fur, under which lies the soft and spongy tongue, a monstrous mass

often ten feet broad and eighteen feet long.

[Illustration: Clio borealis.]

This whole formation is beautifully adapted to the peculiar nourishment

of the whale, which does not consist, as one might suppose, of the larger

fishes, but of the minute animals, (_Medusæ_, _Entomostraca_, _Clio

borealis_, and other pteropod molluscs,) with which its pasture-grounds

in the northern seas abound. To gather food, it swims rapidly with open

mouth over the surface; and on closing the wide gates, and expelling the

foaming streams, the little creatures remain entangled by thousands in

the fringy thicket as in a net; there to be crushed and bruised by the

tongue into a savoury pulp. Fancy the vast numbers requisite to keep a

monster of seventy tons in good condition.

The back of the whale is usually of a fine glossy black, marked with

whitish rays, which have some resemblance to the veins of wood. This

mixture of colours presents an agreeable appearance, especially when

the back of the fish is illuminated with the rays of the sun. The under

part of the trunk and of the lower jaw is of a dead white. The skin is

about an inch thick, and covers a layer of fat of fifteen inches; a most

excellent coat for keeping the whale warm and increasing its buoyancy,

but at the same time the chief cause which induces man to pursue it with

the deadly harpoon.

The usual march of the whale over the waters is rarely more than four

miles an hour, but its speed increases to an astonishing rapidity when

terror or the agonies of pain drive it madly through the sea.

In its sportive humours it is sometimes seen to spring out of the water,

and to remain suspended for a moment in the air. On falling back again

into the sea, high foam-crested fountains spout forth on all sides, and

mighty waves propagate the tumult in widening circles over the troubled

ocean. Or else it raises its bulky head vertically on high, so that the

deceived mariner fancies he sees some black rock looming out of the

distant waters. But suddenly the fancied cliff turns round and brandishes

playfully its enormous flukes in the air, or lashes the waters with such

prodigious power, that the sound rolls far away like thunder over the

deserts of the ocean.

Strange to say, the giant is of so cowardly a nature, that the sight of

a sea-bird often fills him with the greatest terror, and causes him to

avoid the imaginary danger by a sudden plunge into the deep.

Besides man, a vast number of enemies, great and small, persecute the

whale and embitter his life.

The Sword-fish (_Xiphias Gladius_) and the Thresher or Sea-fox, a species

of shark (_Carcharias Vulpes_), often attack him conjointly and in packs.

As soon as his back appears above the water, the threshers, springing

several yards into the air, descend with great violence upon the object

of their rancour, and inflict upon him the most severe slaps with their

long tails, the sound of which resembles the report of distant musketry.

The sword-fish, in their turn, attack the distressed whale, stabbing from

below; and thus beset on all sides, and bleeding from countless wounds,

the huge animal, though dealing the most dreadful blows with its enormous

tail, and lashing the crimsoned waters into foam, is obliged to succumb

at last.

The Greenland Shark (_Squalus borealis_) is also one of the bitterest

enemies of the whale, biting and annoying it while living, and feeding

on it when dead. It scoops hemispherical pieces out of its body nearly

as big as a man's head, and continues scooping and gorging lump after

lump, until the whole cavity of its belly is filled. It is so insensible

of pain, that, though it has been run through the body, and escaped,

yet after a while Scoresby has seen it return to banquet again on the

whale at the very spot where it received its wounds. The heart, as is

frequently the case with gluttons, bears no proportion to its vast

capacity of stomach; for it is very small, and performs only six or eight

pulsations in a minute, continuing its beating for some hours after

having been taken out of the body. The body also, though separated into

any number of parts, gives evidence of life for a similar length of time.

It is therefore so difficult to kill, that it is actually unsafe to trust

the hand in its mouth though the head be separated from the body.

Strange to say, though the whale-fishers frequently slip into the water

where sharks abound, Scoresby never heard an instance of their having

been attacked by one of these voracious monsters. Perhaps they are loth

to attack man, looking upon him as their best purveyor.

[Illustration: Saw of the Saw-fish.]

Fishermen relate that the whale and saw-fish, whenever they come

together, engage in deadly combat; the latter invariably making the

attack with inconceivable fury.

"The meeting of these champions proud

Seems like the bursting thunder cloud."