THE SITUATION AND GENERAL APPEARANCE OF THE ISLAND, WITH A DESCRIPTION OF ITS STRATA AND VOLCANIC PHÆNOMENA.
THE island of ST. HELENA is situated in that part of the southern Atlantic, which has been otherwise denominated the Æthiopic Ocean, about a thousand miles to the southward of the æquinoctial line, and nearly at the same distance from the western shore of Africa. Its remote appearance, when first discovered by those who approach it, is that of a blue mountain, ragged and depressed at the extremities, and rising very high towards the middle parts, which are less distinctly discerned through the exhalations that rest upon them. From its great elevation, and the purity of the surrounding atmosphere, it is seen at the distance of seventy or eighty miles; and the horizon, which in the benign and temperate region of the Æthiopic, is generally clear and bright, or only overspread with light filmy clouds, assumes a darker and thicker appearance over this mountainous land; while a long train of haze and vapour is seen stretching to windward of the island. This last circumstance is occasioned by the influence of its high land on the exhalations, brought by the south-east trade wind, which blows here nearly the whole year round. As we approach nearer, the land grows more ragged and uneven, and seems now only an irregular heap of broken rocks and hills, which rising abrupt and perpendicular from the water's edge, spire up to a great height, and form, in several places, stupendous overhanging cliffs: they are divided from each other by very narrow valleys, or rather by deep irregular chasms. Nothing in nature can be imagined more barren and dismal, than the aspect of these hills and their declivities, as viewed from the sea. They are black, ragged, and mouldering, without any tree, shrub, or trace of verdure; and the wild inhospitable air of the whole island makes the remoteness and solitude of its situation appear still more forlorn and wretched.
The hills which border on the sea, generally project a little way beyond the stoney beaches of the intermediate valleys, so that the whole coast describes an irregular, indented line, which, from point to point, measures twenty-eight miles in circumference. The greatest length of the island is ten miles, and its greatest breadth between six and seven. The hills, nearest the sea, are from eight to twelve and fourteen hundred feet in height. Those inland rise much higher; and Diana's Peak, the most elevated part of the ridge which runs from south-west to north-east, is two thousand six hundred and ninety-two feet, above the level of the ocean. From the base of this central ridge, which rises into several peaks and lofty summits with very steep and abrupt declivities, and resembles an elevated ground, intersecting the country, the surrounding hills slope and descend towards the sea. The narrow valleys too, which diverge all round, begin here; and the small brooks that water them, take their rise in these heights, which, when we approach them, we find altogether unlike the hills on the coast, for they are covered with the finest verdure.
It is a striking and singular circumstance with respect to this island, that the ordinary course of things, which takes place in most other countries, is here inverted; that fertility and verdure are only found in the loftiest situations, and that the lands, both hills and valleys, become barren and unfruitful, as they descend towards the sea. The highest summits and their steep declivities, with every little terrace that juts out from their sides, as well as the intermediate hollows, are all covered with the most luxuriant vegetation; while the lower hills on the coast, and most of the valleys that lye between them, are not only naked and barren, but from their mouldering composition and the decay which has taken place, they have an aspect of rudeness and desolation, which it would be difficult to describe, and not easy to conceive, without having seen them.
Such an appearance of nakedness and sterility presenting itself in the middle of the ocean, seems more likely to repel than to invite settlers. And yet the possession of this unpromising spot, which nature had removed so far from strife and contention, has been disputed by the nations of Europe, because it abounds with excellent water; affords a convenient place of refreshment to fleets, and may, in time of war, be converted into a military station of great strength and importance. It was first discovered by the Portuguese in 1508, who falling in with it on the 21st of May, which is the feast of St. Helen, gave it the name which it still retains. The English made a settlement on it, in 1660; and in 1673 the Dutch took it by surprize. It was retaken, the following year, together with the Dutch ships in the roads, by Captain Munden: and has remained ever since in the possession of the English East India Company.
The history of discovery and colonization is too often the history of injustice and oppression; of countries invaded, because they were rich and valuable; and of their inhabitants enslaved or exterminated, because they were weak. Happily, the settlement of this barren island has afforded no opportunity of increasing the catalogue of crimes, committed by the discoverers of new regions. It was found without any human inhabitants, without quadrupeds, and almost without birds. For excepting some species of sea fowls, which still hover about its coast, and the man of war and tropic birds which annually resort thither, to build their nests in the cliffs, no other kinds seem to have found their way through the vast solitude of the ocean to this remote isle, which was only covered, in a few places, with some indigenous shrubs and plants, and these neither numerous in their kinds, nor very abundant. The sea tortoise, which now frequents the narrow strands and coves about the shore much seldomer than formerly, is perhaps the only creature whose ancient retreat has been disturbed by our possession. In appropriating and subduing the wastes of nature, only to extend and multiply her productions, in diffusing life, together with the means of supporting and rendering it comfortable, and in effecting these benevolent purposes without injury or injustice to others, man would exercise a noble prerogative, befitting the rank which he holds in the creation: But it is to be lamented, that Europeans have seldom traversed the ocean, for the purpose of practising this rare beneficence. The progress of their discoveries, if we except those made in the present reign, instead of diffusing the benefits of nature, and communicating the advantages of culture to remote lands and their inhabitants, has too frequently been marked by rapine and injustice. From the painful recital of the wrongs committed by them on the opposite shores of America and Africa, we may turn with a momentary satisfaction, to contemplate the appropriation and improvement of a desolate and barren spot; the rise of an establishment, effected without injury to anyone; and a little colony speaking the language of England, in a remote island of the Æthiopic Ocean.
It may also gratify the curious to observe, in a minute description of this island, some very remarkable vestiges of those great subterranean operations, which have successively changed the face of the globe; and which working invisible in its bowels, and reaching through inscrutable depths and communications, can only be known to mankind by their more immediate and destructive violence on its surface; or by those wrecks and monuments which they leave behind them, after they have spent their force and activity. The whole structure and composition of ST. HELENA seem to demonstrate, that it is the work of subterranean fire; though many appearances render it probable, that its formation has taken place at a very remote period of time, and that the causes to which it owes its peculiar structure and elevation above the waves, have for many ages ceased to exert their agency. However violent these may have been in their immediate operation, and however dreadful their effects on the surrounding elements, the circumstances which have finally exhausted their force, have left this little Island, and the circumambient ocean and atmosphere, in a settled temperament, which at present is never disturbed by any violent agitation. The season of rest and tranquillity seems here to have succeeded to a long period of convulsion; and the ancient seat of volcanic fires and subterranean explosion, has become the stable and temperate abode of plants and animals. It still, however, retains much of the rudeness of its original form, and it has received many deep impressions from the hand of time, which, collectively, as has been observed, give it a singular wildness and irregularity of aspect. But it enjoys a most serene, salubrious, and unruffled climate; and its high desolate coast conceals from the view of those who approach it, many spots of fine verdure, and delightful recesses, which derive a fresher colouring from the gloom and horror of the naked hills that surround them.
In viewing these hills, the first circumstance that strikes an observer, is the stratified appearance of their declivities, consisting of layers which rise one above another, from the bottom to the summit of the hill. All the matters of which the island is composed, are in this manner placed in beds of strata, very various in their depth, colour and texture; and though in many places they are very irregular in their direction, they seem in general, in penetrating the hill, to ascend obliquely from the base to the summit. On the steeper declivities, the projecting ends of the strata resemble flights of steps; some of them quite regular, and others indented. In the gentler ascents, this appearance is less discernible, or entirely lost under a mass of loose fragments, which have been thrown down from the summit. But wherever the declivities are steep and naked, we observe the strata disposed, like flights of steps, rising one above another, and shewing at different heights, a great variety of tint and colour.
All these layers consist of rock, placed alternately with deep beds of volcanic matter, and thinner layers of variously coloured clays. This rock, which forms the principal strata of the island, and is found in the highest and lowest situations, appears evidently to be basaltes. How far it resembles or differs from the basaltes of other countries, which the writer has had no opportunity of examining, will best appear from a more particular account of its sensible qualities, structure, and disposition. It is a ponderous close-grained stone of a flinty hardness, and generally of a dark blue or black colour; though in some situations it is red, and in others differently coloured, in different portions of the same rock. It is never found in large undivided masses, like the granite, but is always regularly fissured, and running in distinct layers. These layers have always somewhat of a columnar appearance, as they consist of perpendicular portions of rock, separated from each other by vertical fissures, and generally traversed by horizontal fissures also, which give them the appearance of fragments placed artificially one upon another, like the stones of a building. The front of the columns is sometimes flat, but more generally prominent and angular; and in a few places, the whole is regularly prismatic. It is near the water's edge, and towards the summit of the hills, where the rock is most denuded and prominent, that this basaltic appearance is the most evident and striking. In some of these situations, we find a series of columns of equal height, and which, from the uniformity of their structure, resemble a piece of artificial work. Though it is only in a very few places where we recognise so much regularity; yet in every part of the island, even in the wildest and most irregular masses of rock, we can always observe some tendency towards this columnar form; and in the quarries from which stones are dug, they are found to separate in this shape, and often regularly so.
The columns, though commonly perpendicular, are sometimes oblique, and often beautifully curved in the summits, which are adapted to each other; and sometimes the whole is shivered into minute fragments, which yet preserve their natural position. In general, however, the central parts of the rocks are close, compact, and of a uniform texture; and it is in the upper and lower parts, where it terminates in the contiguous beds, whether of clay or volcanic matter, that we observe the greatest variety of appearances. Here it is commonly honey-combed, scorified, leafy, or flaky; or terminates in round knobs or kernels, consisting of spherical plates, easily separable, the inner surfaces of which are of a rich indigo colour. The scorified parts too are tinged with a great variety of colours; and it is remarkable, that several places of the bases and summits of the rock are quite black and scorched, as if from the effects of recent fire. They are also full of large excavations, some of which are filled with volcanic fragments, strongly cemented together. It is observable too, that the rock in some places terminates above and below, in an indurated blue or black clay, continuous with it, but passing so insensibly into it, that we cannot discern at what point the stone ends, or the clay begins. This clay is always full of holes and internal cavities.
The rocky strata are of very unequal thickness, some of them being sixteen or twenty feet; others not above one foot; and this difference of depth we have frequently an opportunity of observing in the same stratum of rock, as it traverses the declivity of a hill, where it discovers, in its upper and under parts, all the variety of appearances which have been described.
Although in all these rocky strata, whether of a greater or less depth, we can generally trace somewhat of the columnar disposition, yet from the scorifications of their bases and summits; from their terminating above and below, at unequal distances, and from the waste and separation which have taken place, the whole becomes ragged and uneven; and the face of the hill at first sight discovers nothing but stupendous projections of rocks, with huge excavations, and overhanging crags. But on examining things more nearly, we find, that the middle of the rock, where it has not been injured by time or the effects of fire, consists of perpendicular portions, distinct and separate from each other. Though this is most striking in the strata of the greatest depth; yet even where the layer is not more than a foot thick, it is found to consist of angular fragments, the upper and under surfaces of which shew all the same appearances that are observable in the summits and bases of the deeper strata.
In describing the direction of these strata, it was observed, that they are commonly parallel with the base of the hill, and that in penetrating its substance, they appear to pass obliquely upwards. But though this is true, with respect to the greater part of them, there is much variety in the direction of others; so that they are found in every position, from the horizontal to the vertical. Even the parallel and horizontal strata, which compose the main bulk of the hills, are so various and irregular, that it is difficult to convey a distinct idea of them. They are in many places, perfectly even and æquidistant; in others, indented and curved; broken and interrupted. Here and there, they approach very near each other; and again receding, leave a wide intermediate space, which is occupied by an irregular mass of agglutinated volcanic matters. Sometimes, a huge columnar bed of rock, twenty feet deep, is gradually contracted into a thin layer, not above one foot thick, which extending a considerable way, again swells out to its former depth, and terminates in a series of columns, the bases and summits of which are so black and scorified, that they look like trunks of trees, burnt to charcoal, at each end: For it must be remembered, that some effects of fire are always apparent in the upper and lower parts of the rock; especially where the superincumbent and subjacent matters consist of volcanic fragments and scoria. Here it is not only shivered, leafy, and tinged with a variety of colours, while the middle is a close and compact blue stone, but it is also spongy and porous, and full of large cells and interstices, like those in clay or dough, which are occasioned by heat. When the contiguous strata are clay, the extremities of the basaltic rock are more regularly defined, and have fewer impressions of fire.
The cells and caverns, which have been described as peculiar to the summits and bases of the rock, are sometimes met with in the centre of it; and this is often attended with a curious circumstance. In a quarry, situated in the interior part of the island, where these blue rocks are dug out, for the purposes of building, and where they readily separate in a regular shape, the stone when broken, is found to have many large internal cavities, which contain a pure and wholesome water. They are generally quite filled with this water, which is shut up in the body of a rock, of the closest and most compact texture.
Having endeavoured to give some account of the rocky strata, it may be necessary to say something of the other matters which are placed in alternate layers with them; that the general fabric and composition of the island may be more clearly understood.
The bed of rock is frequently confined, both above and below, by a huge mass of small fragments, irregularly blended, and strongly cemented together, by a grey, red, or black matter; though in some places the whole is friable and mouldering. When these fragments are examined, they are found to be the same sort of light, porous, honey-combed, and scorified stones, which are so profusely scattered over the whole surface of the island. There is much variety in their colour, texture, and specific gravity. The matter that cements them together, and through which they are found dispersed, appears to be a lava, which is equally various in its colour and texture. The intermediate masses, which these compose, and which separate the strata of rock, are in some places of the height of twenty feet or more. But they are of very unequal depth, though, like layers, they form continuous beds, quite round the hills; and at different heights, are interposed between the ascents of rock. On this they encroach so much in some places, that only a thin layer of stone is discernible, passing regularly through the mass, and united at each end with the bed of rock, of which it forms a part. Frequently, eight or ten successive ascents of rock are separated by these volcanic masses, without any other interposing matter; and from the waste and decay which have taken place, nothing of the kind can be imagined more frightful and threatening than many of the declivities, full of deep excavations, with overhanging masses of loose rock, fragments of which are ever and anon tumbling down. The effects of this decay and separation are in some of the declivities very curious and striking: For the beds of basaltic rock being often wavy and serpentine in their course, the waste of the subjacent matters has left very deep excavations, which are surmounted with arches of stone, like a series of artificial bridges.
Together with the volcanic masses, above described, there are numerous layers of clay, extremely various in colour, texture and hardness: That of a bright red is most common. It is often seen in layers of only a few inches thick, which divide the contiguous strata of rock, and extend quite round the hills, in a horizontal direction, or only varying a little from it. In other places, it runs obliquely, following the direction of the beds of rock, between which it is interposed. These red veins traverse the whole island, and are found in the highest and lowest situations. It has a very beautiful effect, disposed in regular and uniform lines through the black volcanic matter. Besides the red, which is the most common, there are clays of all other colours; particularly yellow, blue, purple, and indigo, which are sometimes blended in the same layer.
All these clays, when examined, are found to correspond, in several respects, with the structure and appearance of the basaltic rock, which has been described: For not only are different parts of the same layer differently coloured, but the layer itself is found regularly fissured, separating into uniform and angular portions, and in some places it is distinctly columnar. Like the rock too, the clays are found leafy and flaky, or disposed in knobs and kernels, consisting of concentric lamellæ, whose interior surfaces are tinged with a variety of rich colours; as are all the interior surfaces of the regular portions into which the argillaceous layers are fissured, in a way similar to what takes place in the rock. Although the layers of clay and beds of rock are distinctly separated from each other; yet portions of them are always found, intermixed. In the heart of the rock, we find nodules and kernels of clay; and among the clay, we find nodules and kernels of rock, together with spongy, porous, and cellular stones. It is observable too of those argillaceous layers, that they have generally dispersed through them, nodules of clay of greater hardness, and differently coloured, from the layer itself. In a stratum of yellow clay, there was found a vast quantity of nodules, of the size of pistol balls, extremely hard, and of the brightest red, indigo, and Prussian blue. The clays so frequently take this shape, that in the interior of the island, where the kernels and nodules have been washed from the sides of the hills, and exposed in the bottoms of the vallies to the attrition of the waters, they look like a collection of pebbles, most beautifully coloured and variegated; and so strong is the deception, that it is only by breaking and crumbling them, that we are satisfied of their not being stones.
In the hills that border on the sea, the clays only appear in thin layers, interposed at different heights, between the beds of basaltes. Further inland, they are found more abundant, and seem to be the principal matter of which many of the interior hills are composed; interspersed, however, with some beds of the same basaltic rock, and the same volcanic products, as near the shore. This difference in the component parts of the exterior and inland parts of the island, though in their fabric they are corresponding and analogous, is very striking. The whole circumference, consisting of steep and abrupt hills, divided by deep and narrow valleys, discovers nothing but beds of rocks, such as have been described, placed between volcanic masses, or here and there separated by thin layers of differently coloured clays, particularly red. But the interior hills and ridges, which are much higher, are composed principally of clay. Some of them are covered with verdure; and those that are naked and barren, discover such a variety of bright and beautiful colours, that no description can convey an adequate idea of them. This variety of appearances on the face of the island becomes the more striking and remarkable, as the whole may be viewed at one glance; and scenery the most opposite and various seen in contrast. From the top of the high central ridge of hills, which intersects the island, there is perhaps one of the most singular prospects in the world. This ridge, which spires up into several peaks and eminences, is covered to the summit with the most luxuriant herbage, and with groves of indigenous and exotic shrubs and trees. Lower down, we observe numerous groups of argillaceous hills, with conical and pyramidal summits, all perfectly naked, but richly coloured with a variety of very bright tints. Intermixed with these hills, or resting on their summits, we see some huge detached masses of rock, which rise several hundred feet above them. Beyond this, the exterior parts of the island, all round where they border on the sea, present the appearance of a burnt and scorified shell, black, ragged, and mouldering, and without the slightest apparent trace of vegetation.
But, notwithstanding this difference in the composition and appearance of the parts bordering the sea, and of those inland, the same analogy of structure, and the same principle of order, are common to both; and seem to extend through the whole island. In the argillaceous hills, we observe a disposition similar to that in the rocky ones near the shore, and the layers of clay are seen rising one above another, like flights of steps, and sometimes distinguished by their difference of colour. But these appearances are seen less distinctly than in the rocks: For these hills are generally much cut and disfigured with ravines, which have formed some of their declivities into steep and broken ridges, and the clays of different colours which have been washed down are blended together; so that the whole becomes irregularly variegated. Nothing can be brighter than the various tints of colour which these cliffs exhibit.
Through all these clays, which, in their structure and disposition, bear so great a resemblance to the rocks, we find dispersed, though in a much smaller proportion than near the shore, the same basaltic stone, and the same volcanic scoria, together with a very ponderous lava, resembling iron recently fused. In the deep valleys and chasms, between the argillaceous hills, where the superincumbent parts have been washed away, we also observe in some places, a series of columns of rock, uniting the bases of the opposite hills and ridges, over which streamlets of water form cascades. At the summits too, and in the middle of the ascents, masses of columnar rock are seen here and there projecting.
It is in this part of the island, viz. among the argillaceous hills, that one is particularly struck with an appearance, which, though it is seen more or less in every part of ST. HELENA, is most remarkable where the clays superabound. One observes here, besides the horizontal and parallel strata of which the hills chiefly consist, that they are all penetrated by huge perpendicular strata, of loose and broken rock; and that they are also traversed by septa or oblique ridges, which divide their declivities into spaces, triangular or curved. These septa are composed of clay or rock, or a matter so nearly allied to both, that it is difficult, from its appearance, to tell which. With respect to the perpendicular strata, which descend from the summits to the bottoms of the hills, they are composed, as far as they could be examined, of a red, grey, or blue rock, often of great breadth, and all regularly fissured, the fragments in many places being quite separate and distinct; but as uniformly fashioned and evenly placed, as the stones of a building. Several of these vertical strata rose considerably above the plane of the hills, which they penetrated, and presented the appearance of huge walls of stone, surmounting their summits, and descending along their declivities to the base. The fragments which compose them are of all sizes; some of them being six or eight feet long, and others only a few inches, but so regular and smooth, that they seem well adapted to the purposes of masonry, without the aid of the hammer or chissel. It is to be observed, that the fissures in the vertical strata are often in the direction of the stratum itself; and, in some places, they separate the whole mass into perpendicular columns, which are again subdivided by horizontal fissures into regular portions. Others of the vertical beds consist of flat fragments, placed horizontally on each other. But a great variety of fracture occurs in different situations, and even in different parts of the same mass of rock.
From this disjointed texture, the vertical strata which occupy the steeper declivities, become subject to what may literally be called dilapidation. In these places, they are seldom observed to be elevated much above the face of the hill, as the fragments separate and tumble down, in proportion as the surrounding soft parts decay, or are washed away: Yet, on the very summit of the hill, a portion of the stratum frequently remains entire, and rises to an amazing height. There is a singular groupe of these detached masses on the south side of the island, to which the inhabitants have given the names of LOT, LOT'S WIFE and DAUGHTERS. They rise to an astonishing height, above the top of the hills on which they stand; and though they seem at first sight, detached and unconnected masses, they are found, on examination, to form a part of the vertical strata, and probably from their position have resisted the decay which has taken place in the declivities. They are composed of distinct fragments, such as have been described, and have a most striking appearance, surrounded by deep chasms and tremendous precipices, and with clusters of argillaceous hills, the most picturesque and romantic, whose summits are all regularly fashioned; and discover every tint of colour, excepting that of vegetable green. Over all this part of the island, which borders on SANDY BAY, there is a wildness in the surrounding scenery, surpassing every thing which the writer of this has ever seen. One feels here, as if transported into a new planet, where every object strikes by its novelty, and is altogether unlike any thing which he has met with before. All the surrounding hills, cliffs, rocks, and precipices are so strangely fashioned, and so fantastically mixed and blended, that they resemble more the aerial shapes, which we see among the clouds, than any thing composed of denser materials.
Besides the vertical strata, which are seen on each side of the hills, descending from the top to the bottom, and which in several places rise to a great height above their summits, there are some large insulated and conical masses of the same broken and fissured rock, apparently unconnected with any extended strata, which project perpendicularly through the hills, or from the chasms and narrow valleys between them. There is one of these in a hollow, on the south side of the island, of an immense size and great height, and of an irregular conical shape; and so much broken and fissured all through, that it seems surprising it has held together. One thing seems evident, that all these fissures must have been acquired in the position in which the stone now rests, as it could not possibly be moved or displaced, without disturbing the order of its component parts. Had these rocks and strata, in their present loose and disjointed condition, being raised by subterranean shocks, the portions of which they consist, must have been jumbled together in the utmost confusion.
Whether the rock which composes the vertical strata, and the insulated masses which have been described, is essentially different from the basaltes of the parallel beds, the writer will not presume to decide: But is has, in several places, a fabric somewhat similar, being composed of long fragments, placed on end, and resembling columns. In the valleys, where there are many large masses, which have been detached from the hills, we find that the body of the rock is regularly divided by fissures into columns, some of which are angular.
On the sides of some of the highest hills, a very curious appearance presented itself; but from their steepness, and the difficulty of ascending, it was impossible to get near enough to examine it accurately. The appearance was this: The whole, or a part of the declivity, was formed into rows of small vertical ridges, regularly defined at the top and bottom; and having, at the distance from which they were viewed, a considerable resemblance to the pipes of an organ. These ridges were seen at different heights in detached groupes. This appearance, which was very regular and curious, probably proceeded from rock or clay, disposed in a columnar form: For it was too uniform and regular to be the effect of accident.
The foregoing observations, though they have already extended to a considerable length, only comprize what relates to the general appearance, structure, and position of the main strata, of which the island is composed. There are still some detached circumstances which remain to be noticed.
The whole surface of the island is every where overspread with a vast quantity of loose fragments, consisting of splinters of the blue basaltic rock, intermixed with light, spongy, porous, and honeycombed stones, very various in their colour and specific gravity.
No sand is found on the coast, excepting at one place, which, on that account, is called SANDY BAY; and the island on this side, from whatever cause, seems to have suffered greater waste and decay than in any other part. The sand here is chiefly black, and evidently composed of portions of the basaltic rock. All the other little strands and beaches consist of small stones, very various in their colours, and regularly rounded and smooth, but without any admixture of sand. There are some quartzy and chrystallized stones, but no granite; at least, the writer of this could not meet with any. In some of the valleys there is a kind of free-stone; and there are also some beds of marle and lime-stone. The former is of a poor and hungry quality, and the latter is always found in a friable and mouldering state.
On the tops of the hills, there are some masses of rock, broken into regular steps, like trap. The fracture is sometimes upwards, and sometimes downwards. When the latter is the case, the whole exhibits somewhat of the appearance of an inverted cone. Several of these impending masses overhang the paths, which are cut round the brow of the hills, and have a very threatening aspect. Where the summit of the hill is contracted and narrow, the whole is sometimes crowned with a huge angular mass of rock, which, at a distance, has somewhat of the appearance of a bastion; while the indented course of some of the projecting strata below, may not unaptly be compared to the zig-zag of a fortification.
The hills, round the coast, are quite separate and distinct from each other. But, inland, they are all connected with the mountainous ridge which intersects the island. Many of them are irregularly shaped, and there is much inequality in their surfaces, from the waste that has taken place: Yet several of them are very regularly shaped in their declivities and summits; and the layers of which they consist are disposed in an orderly manner, slanting obliquely upwards. Where the summits are the most uniformly fashioned, the layers are observed to be thin, and to ascend with a considerable degree of obliquity, all round the hill. Where one side of the hill slopes, and the opposite is steep, we observe the layers that form the sloping side, to ascend obliquely upwards, and those on the steep or overhanging side to be placed horizontally, or to descend obliquely downwards.
Along the coast, the bottoms of the hills are full of deep excavations, which admit the tides; and close to these there are, in several places, masses of very ragged and irregular rocks, cemented together with a ponderous lava. These rocks are cavernous and hollow, and rise above the surface of the sea. One hears the noise of the subterranean waters passing underneath, into the excavations of the island, or boiling up in whirlpools at the foot of the hills. The depth and extent of these excavations under the hills, into which the ocean penetrates, the writer could not learn. Some vague reports about them, among the inhabitants, as they do not seem probable, need not be mentioned. Where the bottoms of the hills are in this way, hollow and cavernous, there are commonly very high cliffs and precipices, with projecting masses of rock, apparently of so loose a texture, that it is not a pleasant task to explore the recesses which lye underneath them.
The writer is fearful of being tiresome, by the length and minuteness of this description, though he has only noticed the most striking and remarkable circumstances, and endeavoured to give a general though accurate idea of this island, and of the order in which its strata are disposed, without too much encumbering the subject with a detail of the many irregularities that are met with. These irregularities are indeed so great, in some situations, as might induce us, at first sight, to believe, that the island, at some period posterior to its formation, has been exposed to some convulsive and tremulous shocks, which have occasioned so great a disruption and displacement of its strata: Yet the whole strata of the same hill are not found in this state of disorder; and when the middle parts are most confused and irregular, we observe some beds of rock and layers of clay, occupying the base and summit of the hill, uniform and evenly defined, and without any break or interruption. In what manner any shock could have produced the confusion which we see in the middle of the hill, without disordering the strata of the top and bottom, it may be difficult to conceive.