View source for Excursion to Tunbridge Wells and Crowborough Beacon. Monday, July 12th, 1879. (Fifth of the Weald Series) - Geologists' Association excursion

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'''Director: J. Logan Lobley, F.G.S. (Report by W. Fawcett, B.Sc.) Proc. Vol. vi. is. 230.'''

[Note: * As this excursion is the last of the "Weald" series, it is here included among Kentish excursions, though itself mainly in Sussex. Tunbridge Wells is on the Kentish side of the border]

On alighting at Tunbridge Wells the members proceeded to the Parade, the Pump Room, and, after crossing the boundary of Kent and Sussex, to Broadwater Down. Here, with almost the whole of Tunbridge Wells in view, Mr. Lobley pointed out that the town was built at the junction of two valleys. The higher ground is Tunbridge Wells Sand, with outlying patches on Rust-hail Common and elsewhere of Weald Clay, while in the valleys Wadhurst Clay occurs.

The Marquis of Abergavenny had invited Mr. Lobley to conduct the members through Eridge Park to the Castle, and had kindly instructed Mr. Rush, of Eridge, to accompany the party, and point out everything of interest in the magnificent domain, one of the oldest enclosed parks in the kingdom. At Eridge Castle two iron cannon' balls were exhibited, the first made in England. Prof. Morris referred their manufacture to the year 1543, when the first cannon of English make was produced at the then famous Sussex furnaces. A hundred years later, during the Civil War, many of the furnaces were destroyed, and from that time the gradual extinction of the old forest of the Weald, and the consequent loss of fuel, led to the decline and ultimate cessation, in the beginning of the present century, of the Wealden iron-furnaces. But the loss has only been a local and a temporary one. Some three or four of the ironmasters of Sussex, finding fuel growing scarce in their own country, established themselves in Wales, and were the first promoters of the iron-trade of Merthyr Tydvil and Aberdare.

From the lawn in front of the Castle there is a good view of the well-wooded Wadhurst Clay Valley, which forms a large portion of the grand old park. The Eridge Rocks in another portion of the park were examined, and compared in many points with the Toad and High Rocks. The position of the Eridge Rocks, inasmuch as they are in a sheltered position, seems to, militate against a theory of Sir A. Ramsay, who endeavoured to account for the peculiar undercutting by pointing out the enormous force with which the wind files away at the base of the rocks by means of the sand—a natural emery powder. A discussion arose with regard to the origin of the hemispherical markings. Mr. Lobley suggested that they were structural, and compared them with the "box-stones" of the Sevenoaks Quarries. Professor Morris pointed out that they followed the lines of false bedding. This false bedding proves the existence of varying currents in the great river which laid down the Tunbridge Wells Sand as part of its delta. Attention was called to a very " clean " cleft. It is remarkable that these "clefts" run parallel in a direction nearly N.W. and S.E.

The party left Eridge and followed the road to Uckfield. Gradually ascending, they soon found themselves on ground commanding most extensive views, as well over the cultivated region as over the wild expanse of Ashdown Forest, stretching away to the west. Still ascending, Crowborough was at length reached, and standing on the summit Mr. Lobley reminded the members that they had now arrived at the anticlinal axis of the Weald, from which the beds dipped north and south;, that they had traversed first the long northern slope of the Chalk ridge of the North Downs, had then descended its steep escarpment on the southern side, crossed the Gault vale, and, at Sevenoaks, the Lower Greensand ridge, and then the Weald Clay valley of the Medway, followed by the Tunbridge Wells Sand ridge and the Wadhurst Clay vale, from which they had ascended the great swelling mass of Ashdown Sands, on which they now stood. The parallel ridge and valley character of the country had been well seen; the long slopes and the escarpments, the varying character and appearance of the country, and the change of vegetation following the change of formation had been noted. Professor Morris remarked on the absence generally of gravel beds in the Wealden area, and said that where these did occur they went to prove that the direction of the rivers had always been the same, though S. V. Wood, jun., maintained that the contrary was the case in the north, from the existence of trumpet-shaped gorges in the North Downs. He showed that if the Chalk had covered the Beacon, we should have to account for the 'denudation of some 3,000 feet, but it was quite possible that Crowborough Beacon formed a bank in the Cretaceous sea.<ref>* Sheet 77 of the Horizontal Sections of the Geological Survey, from Newhaven to the North Downs two miles S.E. of Farningham, in Kent, crosses Crowbotough Beacon and Knole Park.</ref>

==References==
===Maps===
Ordnance Survey. Geological, Sheet 6. 8s. 6d. 

New Ordnance Survey. Sheets 287 and 303. 1s.
===Books===
W. Topley, The Geology of the Weald, etc. 8vo. London (Geol. Survey), 1875. 28s.

W. Whitaker, The Geology of London, etc. 8vo. London (Geol. Survey), 2 vols. 1889. 11s.
== Footnotes ==

[[Category:Geologists' Association excursions]]