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thrown up. The land gains here decidedly upon the sea. Vast masses of cliff several hundred feet in length have sunk at the edge of the cliffterrace near St. John's church, and likewise higher up near Union in the parish of St. Joseph: they sunk directly downward, so that the soil and vegetation remained upon it. In other places these detached portions are of less extent, and assume the forms of towers: this is the case near the churchyard of St. John's, above Codrington College and near Black Bess: the last is upon a gigantic scale.

The occurrence of hillocks between two lines of terrace is very common; they are perhaps analogous to the low islets which are sometimes formed on reefs. There are two such hillocks behind Grand View Villa, in St. Michael's, which consist of hard calcareous rock with large masses of different species of the genus Astræa imbedded in it.

I refrain from expressing an opinion as to the length of time which elapsed between the epochs of denudation'. Geológically speaking they have not been remote. We possess proofs that Barbados has been elevated gradually to its present height since the epoch of existing shells. I have found species of the genera Turbo, Lucina, and Petricola near Sugar Hill, Chimbarozo, and Mount Wilton, which situations, with Mount Misery, form the highest elevation of the coral rock2.

At these places casts only of the shells are found; while the fossil shells, eight hundred to a thousand feet lower, in many instances still retain their lustre, and do not differ from those found in the adjacent sea, except that the fossil shells are generally much larger than the recent. It is remarkable, that others, which at the period when they were imbedded must have been abundant around the island, are now very rare, or are only found further northward among the Virgin Islands. This refers to Cytherea casta, Tellina lacunosa, Strombus accipitrinus, Turbinella pugillaris, &c. I have found the impression of a Pecten near Fort George. Impressions of shells are otherwise very rare, and this is the only instance of my meeting with one during my researches.

Certain species of shells are firmly imbedded in the coral rock. One shell of a bivalve is sometimes found in the rock with the convex side

1 On the leeward coast, along the road which leads from Bridgetown to Speightstown, after having passed Bat's Rock, there are frequently lines of rounded aud angular pieces of limestone, pieces of corals, &c., heaped one upon another, showing decidedly that it was formerly a shingle beach. I have been told that Indian hatchets have been found among these fragments, which would fix their date of upheaval within an historical period.

* The numerous evidences of elevation within the tertiary period of nearly the whole area which the West Indian archipelago occupies, finds an additional proof in Barbados. The elevatory movement, however slow and gradual, was not accompanied by an intermediate subsidence,-an opinion which is supported by the fact that the few fossil shells found on the central ridge are merely casts, while it is quite different, as above observed, with those found in lower situations.

upwards, while the corresponding shell is met with in the reverse position at a short distance from it. The cuttings of the road above Two-miles' Hill contain Cypræa exanthema, and Venus Pavia: Strombus gigas is found abundantly imbedded in rocks on the road from Constitution Hill to Pilgrim, and likewise near the Pine Estate. Cassis tuberosa is met with in the same neighbourhood; Lucina pennsylvanica in the rocks near Skeete's Bay, Cones near St. Anne's and near St. Stephen's Chapel.

The shells imbedded in marl are more numerous and in better preservation than those in the coral limestone. Some of the recent shells in these beds near Grand View in St. Michael's, and about 165 feet above the sea, have retained their pearly lustre and colour so surprisingly, that one might be tempted to disbelieve that they had been lying buried for ages in the marl. This refers chiefly to specimens of Strombus pugilis, Bulla striata and Cypræa cineraria. I found in the beds of marl several Stalactites, some eighteen inches long, surrounded with calcareous concretions and shells consisting of Lucina edentula, L. divaricata, Venus, and other bivalves. Since Stalactites can only be formed in aërial caverns, their occurrence in these marl beds is curious. They were perhaps swept by freshets into the sea from caverns situated in the cliffs on the dry land, where they were surrounded with these shells and subsequently raised up with the bottom on which they were lying.

Numerous shells of Tellina radiata are found near Hopewell, in the parish of Christ Church. They have lost their striated appearance, and are of a uniform chocolate colour. Two of these shells having remained exposed for some time to the rays of the sun, I saw with astonishment that the heat and light developed again their striated colour, which now appeared of a pale red'. Voluta musica and Murex messorius occur in the same bed of marls as the Tellina radiata. Some very remarkable calcareous concretions, nearly spherical and cavernous, lie in large numbers on the sloping cliffs near Cummin's Hole. The inner part is sometimes formed of concentric layers. They are called by the people “rock-seeds," and vary from the size of a pigeon's egg to two inches in diameter. I have seen them imbedded in the cliffs near the Crane.

At the conclusion of this sketch of the geological structure of Barba- * dos will be found a list enumerating the shells which I collected in the fossil state in Barbados; I have already observed that they are much larger than those of the same species now in the adjacent sea. This refers chiefly to a Turbinella, which has all the appearance of Turbinella pugillaris, only that its size is so much larger than they are found now, being

1 These shells of the Tellina radiata near Hopewell are quite perfect, and consist of every variety of size, from half an inch to three inches, a sure proof that they must have existed in families. There is another remarkable circumstance connected with them, they are frequently bored like many of the shells in their recent state. These holes are ascribed to some species of the Order Trachelipoda; they have been therefore coexisting with the Tellina. This hole is likewise seen in the fossil

T. lacunosa.

twelve inches in circumference. A fragment of a gigantic shell one inchand-a-half in thickness, inclosing a large Petricola, appears to have come from a Tridacna, which genus is at present no longer to be met with near Barbados.

B. THE SCOTLAND FORMATION.

Quite different in appearance and in structure is the "Scotland district," including the hills and hillocks "Below the Cliff." From the semicircular heights which encompass this district, project long ridges of hills as it were towards one point', diminishing in height as they approach the sea. Some small groups rise from the plain in the neighbourhood of Long Pond, Walker's, and Morgan Lewis. The sides of the hills are abrupt, naked and barren, and sparingly clothed with timber. Mount Hillaby forms the highest summit in the island, and rises on the southwestern end of this group, which from its alpine character in miniature, has received the name of Scotland2.

This formation, as far as exposed to view, extends from Cove Bay, in the parish of St. Lucy, to Skeete's Bay in the parish of St. Philip. Doctor Davy, Inspector-General of Army Hospitals, discovered traces of the Scotland series near the northern point of the island.

I have already alluded to the various modifications of tertiary rocks which are found in this district; nevertheless their character under all modifications possesses an original uniformity. The direction of the strata is generally south-west and north-east; disturbances however have frequently altered this direction, and the consequent variation of their planes of stratification renders it very difficult to ascertain their dip. The strata are more or less inclined, and change in some instances in closely allied rocks of sandstone from the horizontal to almost the vertical. The stratification is at other times wavy, and at Chalky Mount3 it is contorted.

The earthy marl, or as it is called in the colony, the chalk, constitutes by far the greater part of the series. It occurs stratified near the northern extremity of the Scotland formation, and vestiges of it are observable even near Cove Bay. Further southward, towards Pico Teneriffe, it appears in vast masses, and the Pico itself rests upon it. The sea, beating with great strength against these marls, has hollowed them out and loosened

The ridges stretch from below Mount Nicholas south-eastward; from below Red Hill eastward; from Mount Hillaby north-eastward; and from Bissex Hill northward. If these ridges were continued, they would centre about St. Andrew's church into one point.

2 It will be recollected that Columbus, when requested to give a description of the mountainous aspect of San Domingo, took a sheet of paper, crumpled it up, and throwing it on the table compared it to the appearance which the mountains presented Such a simile might be used with equal correctness to convey an idea of the aspect which the numerous elevations of Scotland district afford when viewed from Cherry Hill.

3 This is a misnomer, as the hill consists mostly of siliceous and calcareous sandstones, broken into precipitous and rugged cliffs of an appearance as white as chalk.

large blocks from the cliffs, which are now lying on the beach. One of the cliff's has assumed a fantastic shape, and reminded me of the Needles off the

Fig. 9.-Cliff below Pico Teneriffe.

[graphic]

Isle of Wight. Selenite, sometimes in crystals, is found in the marl, frequently lying on the surface. The strata rise to the highest point through the other rocks: the summit of Mount Hillaby consists of earthy marl'.

It abounds in siliceous shielded animalcules, which Ehrenberg has called Polycystina. The number of species which he found in the marl from the summit of Mount Hillaby, amounted to fifty-four, belonging to twenty-two genera. The marl near Jeeve's2, or Boscobelle, contained 113 species of Polycystina, five species of Polygastrica, one Geolithia, and two Phytolitharia. Small patches of marl are likewise met with in the flats of Scotland, on the road from Haggat's towards Belle Plain, near a huckster's shop; it contained forty Polycystina, four Geolithia, and three Phytolitharia, but no Polygastrica. Proceeding southward, the marl is succeeded by sandstones, somewhat ferruginous, frequently gritty and coarsegrained. They dip towards the sea at an angle of about 20° to the north-east, rising however near the Round Rock to a more vertical position, and the stratification is sometimes wavy. This is chiefly the case where the sandstone is interstratified with compact clay-iron. The sandstone is subordinate to the marl. At Greenhill it is micaceous, almost slaty, the slabs being placed edgeways, as if they had been uplifted and the soil between them washed away".

'I cannot conceive why the late Dr. Maycock considered Mount Hillaby as belonging to the coralline formation; the marls and black siliceous sandstones, aluminous clays, &c., extend along the western declivity nearly as far as the Estate Hillaby.

* Below Jeeve's, close to the sea, lies a large block, which has a basaltic (?) appearance.

3 A very marked difference exists in the sand which covers the beaches along the leeward coast, along the shores of Christ Church, St. Philip's, and part of St. John's, and on the other hand those of the Scotland district. The former consists of finely

2N2

Several conical hills consisting of masses of accumulated drift-sand intervene between the sea and the Flats, as the level ground is called which extends westward, and is intersected by the mountain streams, called Church- and Scotland-river. I have already alluded to the existence of some salt-springs on the land which extends behind these hills, without expressing a decided opinion as to their origin'.

On the south-eastern end of the beach which is called Long Bay, rises Chalky Mount to a height of 571 feet, which is highly interesting to the geologist. Its rugged appearance and disturbed strata speak of Fig. 10.-Chalky Mount.

[graphic]

FRED GYDET. SC.

great convulsions. The mountain forms three peaks, and consists mostly of fine-grained sandstone, more or less ferruginous, containing frequently large nodules of ferruginous clay (chiefly between the Hope estate and Mr. Brathwaite's house); at other times the sand is very compact, and has the appearance of passing into jasper. The summit of one of the peaks is capped with coarse conglomerate, and some blocks, which now lie partly in the sea, appear to have rolled down from the summit to their present situation. The fragments are calcareous, sometimes of the size of a pigeon's egg, rounded, seldom angular, and smooth. At Whoop Gully below the sandstone is gritty clay, which is frequently aluminous, and lies in horizontal strata.

On the eastern declivity of Chalky Mount, where that mountain fronts the sea, the strata are apparently much-contorted and twisted; this is chiefly the case where the light-coloured friable sandstone is in contact with a calcareous sandstone containing minute specks of mica; ferruginous sandstone and compact iron ochre rest upon it. The calcareous sandstone is twisted in a most remarkable manner.

comminuted shells and triturated calcareous matter, the latter of siliceous particles, or properly speaking, "sand:" this difference in their nature arises obviously from the relation of the adjacent land from whence the sands were washed down. 1 See ante, p. 224.

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