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Down, and consists of the flinty chalk. The pathway winds over the brow, and leads to Compton Chine, down which a rude foot-track conducts to the beach. The strata at this point are the cretaceous ferruginous sands, which emerge from beneath the Galt on the west, and are succeeded on the east by the Wealden deposits; but the face of the cliffs along the westernmost part of Compton Bay is not seen in this sketch. The strata forming the cliffs, shown in this view, are the sands, clays, and shelly limestones of the Wealden.

The first point of land jutting into the sea, and terminating in ledges or reefs, is the western boundary of Brook Bay; at the base of the cliff is the fossil forest of the Wealden. The limits of Brook Bay are shown by the head-land beyond, which is the eastern point. The farthest land on the shore is the Cliff near Blackgang Chine. Saint Catherine's Hill rises in the remote distance.

Pl. XII.-BLACKGANG CHINE FROM THE SEA-SHORE,

LOOKING NORTH-EAST.

This view presents a fine natural section of the strata composing the Greensand group of the Chalk formation. The highest point in the distance is the escarpment of Saint Catherine's Hill, which is 830 feet above the level of the sea. The upper part of the cliffs is composed of alternating strata of greenish grey sand and sandstone ; from the wearing away of the friable layers the beds of hard grit become prominent, and appear in this view as very distinct, and nearly horizontal, bands of rock. The cliff below the thin bed of ironstone grit, from which the cascade issues, is formed of dark-coloured clay, alternating with ferruginous sand and grit. The long-continued action of the water has produced a deep chasm, or chine, and the stream falls in a nearly perpendicular column from a height

of seventy feet to the base of the cliff, whence it rushes to the sea.*

Pl. XIII. -VERTICAL CHALK STRATA ON BRADING Down.

This sketch shows the vertical position into which the originally horizontal chalk strata have been thrown, in the central range of downs. The layers of shattered flint nodules render the displacement of the strata obvious to the most casual observer.

Pl. XIV.-CLIFFS OF WEALDEN CLAYS IN COMPTON BAY, SEEN FROM THE WEST,

In this view the nearest cliffs are formed by the clays, sands, and shales of the Wealden, which constitute the cliffs and ledges to beyond Brook Point, and almost as far as Atherfield. The inclined position of the strata is well shown in the sketch.

The horizontal layer on the top of the cliffs is an accumulation of drifted materials, composed of gravel, clay, and loam, which in some places is from ten to twelve feet thick, and contains bog-wood, hazel-nuts, &c. The nearest point of land is Bull-face Ledge; and that further to the east is Brook Point, where the fossil forest forms ledges that stretch far out to sea. The extreme land is the easternmost point of Brook Bay. The view given in Plate XI. shows the continuation of the cliffs from beyond Bull-face Ledge to the western point of Brook Bay.

Pl. XV.-CULVER CHALK CLIFFS, FROM THE SEA.
In this sketch (reduced from Mr. Webster's) is shown

*The picturesque character of this interesting spot is admirably shown in the views given by Sir Henry Englefield, and by Mr. Barber, and also in the spirited vignettes on the embellished letter paper published by the booksellers in the island.

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the eastern promontory of the Isle of Wight, which is a vertical section of the chalk range, that extends from this point, in a westerly direction, right through the island to the Needles. The interrupted lines denote the layers of flint, and distinctly exhibit the highly-inclined position of the strata towards the north. The dip varies from 50 to 70 degrees. The distance on the left is Sandown Bay; on the right are seen the eocene strata of White-cliff Bay.

VIEWS ON THE COAST OF THE ISLE OF PURBECK:

Reduced from the beautiful Engravings by Mr. Webster, in Sir Henry Englefield's Isle of Wight.

Pl. XVI.-VIEW OF THE DORSETSHIRE COAST, FROM WORTH BARROW, LOOKING WESTWARD.

This interesting view of the Dorsetshire coast, looking towards the west, is taken from Worth Barrow, a tumulus situated near the summit of a very high precipice of the chalk range. The bay included between the foreground and the detached rocks in the sea is Worth Barrow Bay; the road down to which is seen just beyond the projecting point of the chalk cliff. The rocks bounding the bay are the Purbeck beds, covering the Oolite. The long hill in the middle of the view is the Swine's-back, beyond which is West Lulworth Cove. The Isle of Portland appears in the distance, united to the main land by the Chesil Bank. Weymouth road is indicated by the vessels at anchor.

The deep sinuosities made in the cliffs along this coast by the inroads of the sea are well shown in this sketch.*

Pl. XVII.-LULWORTH COVE, FROM THE WEST.
Lulworth Cove is an almost semicircular bay, formed by

*Sir Henry Englefield's Isle of Wight, p. 183.

the action of the sea on the vertical strata which constitute this part of the coast; and in the section thus exposed the series of rocks, from the chalk to the oolite inclusive, may be traced. A small part of the chalk cliff is seen on the left of the Cove, and from that to the entrance, where the oolite appears, the intermediate strata occur. The upright rocks in the sea near the foreground are masses of the Purbeck beds on this side of the bay, while similar blocks appear on the opposite bar. The argillaceous strata on the side of the hill are curiously contorted from lateral pressure.

Pl. XVIII.-WEST LULWORTH AND COVE.

The village of West Lulworth is situated in a deep valley, formed by an interruption of the chalk range that extends from Handfast Point, through Corfe Castle, to the coast. The Cove, which has been produced by the erosive action of the sea on the chalk cliffs, is about 1,300 feet in diameter, and vessels of a hundred tons burthen may at all times remain here in perfect security.

The hill immediately above the village is the termination of the long ridge called the Swine's-back, which is half cut into the Cove and presents a lofty precipitous chalk cliff. St. Adhelm's head is in the remote distance; the nearer headland, seen above the Cove, is Gad Cliff.

Pl. XIX.-DURDLE COVE.

In Durdle Cove the series of deposits, from the upper flinty chalk to the Portland oolite, is exposed in a nearly semicircular bay walled in by vertical sections of these strata. The chalk appears on the right, forming the high cliff termed Bat's Corner; and in passing from thence round the bay, the Chalk marl, Firestone, Galt, Greensand, Wealden, and Purbeck strata, may be successively traced to the Portland oolite, which terminates the point on the

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left of the sketch. The natural arched rock, called Barn Door, at the entrance of the Cove, consists of Portland limestone.

Pl. XX.-GEOLOGICAL MAP OF THE ISLE OF WIGHT.

Each of the three Formations, or principal groups of deposits, of which the Isle of Wight is composed, is defined by a separate colour.

The pink denotes the tertiary Eocene strata; the shaded parts indicate the London clay, and other marine beds, in which but few, if any, freshwater fossils occur.

The blue marks the Chalk; the chief subdivisions of this formation, namely, the Firestone, Galt, and Greensand, being defined by a difference in the lines of shading.

The sienna indicates the Wealden deposits, which appear in the bays on the east and west of the promontory of the Undercliff.

*

*

* For the original sketch of the Geological Map, and for the drawings of Organic remains, I am indebted to the kindness of Professor Woodward, of the Agricultural College, Cirencester.

The lignographs are by Mr. James Lee, of Prince's Square, Kennington Common.