155

EXCURSION TO CATERHAM, GODSTONE, TILBUR­ STOW, AND NUTFIELD.

MONDAY, JUNE 4TH, 1877.

Director : J. LOGAN LOBLEY, ESQ., F.G.S.

(Report by Mr. LOBLEY.)

Before arriving at Caterham, the party were much interested by seeing the" Bourne" flowing along the bottom of the usually stream­ less, hut st.illbeautiful. Kenley Valley. This intermittent river flows only after unusually wet seasons, the Chalk of the district absorbing ordinary rainfalls. In recent years there were flows in 1866, 1873, and a small How in 1876. This year the flow is large, and is the subject of much comment and speculation amongst the residents of the locality, some of whom even now ascribe tbe appearance of the river to a mysterious or supernatural agency, although in 1660 the true cause was known. Childrey, in the "Briiannia Ilaconica " of that year, says :~" The rising of a bourne 01' stream near Croydon (as the common people hold) prosageth death or the plagne; and it hath been observed to fall out so. The rising of the bournes in places where they run not always we have before proved to be cansed by great wet years, which (according to Hippocrates' observation) are generally the most sickly; and if they prove hot as well as wet (because heat and moisture are the greater disposers to putrefaction), they prove also malignant, and, for the most part, pestilential. And the reason why the risiug of this bourne doth not always presage the plague is because aJI wet years do not presage hot."· Mr. Baldwin Latham, F.G.S., in a letter to the "Croydon Chronicle," dated January 25th, 1877, gives the following par­ ticulars of the flow of the present year :-"The flow of the Bourne from Marden Park and that at Riddlesdown joined each other on Monday, the 22nd inst., and now forms one continuous stream, and the flow is making rapid progress towards Croydon, having this day (Thursday) reached to a point north of Caterham J unction. The Bourne now makes its appearance at the highest

.. "Memoirs of the Geological Survey of Great Britain, Geology of the London Basin." By W. Whitaker, F.G.S., p. 391. 156 EXCURSION TO CATERHAM, point a short distance below Bughill Farm, and from this point to a considerable distance below the Rose and Crown Inn, under Riddlesdown, the water continuously receives considerable acces­ sions to its bulk. The volumes flowing from Marden Park, at Wapses Lodge, have been as follows :-

" On the 19th, at the rate of 1,516,000 gallons in 24 hours. " "20th,, ,,2,567,000 " "" 23rd ,,4,421,000 "" "" 24th "4,623,000,, "" " At this latter date the volume below the Rose and Crown was flowing at the rate of 10,584,000 gallons in 24 hours, while at Warlingham Station, a point intermediate between Wapses Lodge and the Rose and Crown, the volume flowing was at the rate of 6,855,000 gallons in 24 hours. From my last letter it will be seen that the volume of water flowing out of the Bourne Culver, at Croydon on the 15th inst, was at the rate of 9,300,000 gallons in 24 hours. On the 21st it was at the rate of 8,837,000 gallons in 24 hours, and on the 24th inst. at the rate of 8,761,000 gallons in 24 hours. The falling off of the quantity is no doubt due to local effects arising from the diminution of the rainfall." On alighting from the train at Caterham, the Members wore gratified at finding that a collection of the fossils of the Chalk of the neighbourhood had been brought by Mr. Clnse, of Caterham Junction, not only for inspection, bnt also, with great liberality, for distribution amongst those of the party who did not possess specimens of the species exhibited. At a short distance from Caterham Station, on the road to Godstone, a visit was paid to a quarry in the Lower Chalk, and here the Director explained that they were now in the region of the North Downs, and that from Caterham Junction to Caterham, lower and lower beds of the Chalk had been traversed, the section at the Junction showing Mr. Caleb Evans' Upper Kenley, or Riddlesdown, Beds of the Upper Chalk, while this quarry was in the Lower Marden Park beds of the Lower Chalk. These beds are characterised by Belemnites plenus and Ilolaeter subglobosus. An energetic exploration of the Chalk exposed did not, however, result in many organic remains being found, and these were chiefly fragments of Inoceramus. An explanation of the intermittent flowing of the Bourne river was accompanied by the presentation by Mr. Taylor, a Member of the Association, to each of the party of a copy of the article on aODBToNE, TILBURSTOW, AND NU TFIELD. 157 the subject in the "Geology of th e London Basin," p. 391, a large numb er having been printed by that gentleman for distribu­ tion on thi s occasion. Heavy rain arrested pr ogr ess for a little time, but on its cessa­ t ion th e par ty speedily made th eir way to th e great Firestone quarri es in the Upp er Greensand, on the Godstone road, which have been worked underground for a long period, though they arc not so ancient as others a little distance to the west, from which stone for ·Windsor Castle was obtained in th e time of Edward III. By the kindness of th e Manag er, the Members were provided with candles, when th e galleries were ent ered by almost the whole of th e party, and explored to their furthest extremities, where the actual hewing of the blocks or slabs of the Firestone was being activ ely pr ose­ cuted. Though at the ends of the workings there are places in which a considerable quantity of water lies, the gall eries, along which trams are laid, are comparatively dry. A considerable tim e was spent in the workings, and the Members were glad to emerge into the warm sunshine after the cold dampne ss of th eir subterr anean visit. Th e Firestone is quarried from a calcareo­ siliceous bed of th e Upper Greensand, which has an extension not limited to Surrey, since it is worked as far west as 'Vantage, in Berks. Curiously enough, however, near to th e opening to the quarr ies anoth er excavation had been made, but no Firestone had been met with. A t thi s place some fossil sponges, Siplio nia, were found by two or three Members. Un der the g uidance of the Manager of th e Quarri es, a visit was paid to a quarry near Marden P ark , in which a harder stone, used for hearthstones,occurs. P roceeding southwards, an exposure of the Gault was found in a field t o the east of th e Godstone road, and a few fragments of th e characteristic B eleumitella minima were extracted from th e clay. After passing a pit in which a fine white sand is work ed, an exposure of Lower Greensand, the pretty village of Godstone WIlS entered, and at th e picturesque roadside inn the party stopped to enj oy a substantial luncheon. After luncheon the road to Tilburstow Hill was taken, and It "head-water" of the Medway, Broad Mead Water, having been crossed, the ascent of th e commanding elevation of 'I'ilbur­ stow commenced. A deeply- cut disused lane, almost covered by tangled vegetation, opens on to a fine breezy expanse on th e hill side, and here the party paus ed, and, turning to th e north, sur- Li S EX CURSION TO CATEllIlAM, veyed the beautiful valley they had just crossed, lying between Tilburstow Hill on which they stood and the Chalk hill s of th e North Downs. The bare, but green Chalk hill s on th e opposite side of the valley, diversified with white patches where excava tions occur along th eir sides, contrasted with th e darker green and well-wooded lower ground of th e Upper Greensand and Gault. The Lower Ohalk of Oaterham had g iven place to th e Upper Greensand of th e Fireston e Quarri es, and thi s had been succeeded by the Gault of th e bottom of the valley and th e Lower Green­ sand, th e commencement of which had been seen at the God­ stone sand-pit, and of which the whole of 'I'ilburstow Hill was com­ posed. Thus a regular and continuous sequence of beds had been traversed from Oaterham Junction to the spot on which th ey stood. Oontinuing the ascent, th e party soon reached the summit of the road, where a fine section of the ferruginous sands of which th e Lower Greensand so largely consists, is exposed. The tendency of the oxide of iron to separate from th e sand and form " boxes" is well exemplified at thi s place, and some good specimens of th ese structures were obtained. Th e top of the hill is much high er than the summit of th e road , and is only gained by a very steep and difficult path; but th e difficulty was soon overcome by the enthusiasm of the Members, who one by one emerg ed from th e brushwood and stood on the little plateau under th e trees which crown the summit of Tilburstow. Those who had not pr eviously visited thi s spot were struck with the extent and extreme beauty of th e landscape which met th eir eyes, for, stretching to th e east and st retching to the west, and extending to the south as far as th e eye could see, lay before them th e great W ealden V alley, with its verdant pastures, its orchards, and its woods glorious with the foliage of th e leafy month of June, all bathed in the sunshine of a bright summer day. With the aid of the Geological Survey Maps, embracing the ent ire W calden Area, the Director described the physical features of this great valley of uph eaval bounde d by the North and South Downs-the middle of which, the Forest Ridge, being higher than the sides-and explained the theories held to account for the denudation of th e great mass of Oretac eous strata which had been removed. Mr. Boulger having said a few words on th e plants of the neighbourhood, the party left th e hill top, and after visiting some Kentish Rag quarries in the Lower Greensand, GODS TONE, TILBURSTOW, AND NUTFIELD. 159 made their way westward along the hill, through the villages of Bletchingley and Nutfield, to the well-known Fuller's-earth pits, also in the Lower Greensand. The argillaceous earth here worked is finer than that of the formation called the Fuller's Earth, and is largely used in the arts. Masses of barytes occur in these pits, and, when broken up, show fine brown crystals, sometimes having small cubical crystals of iron pyrites attached. Nearly every member of the party succeeded in carrying away a good specimen. A further walk of about a mile brought the party to Redhill, where the now tired Geologists gathered round the tea-table of the hotel, and, after the usual compliment to the Director, took the train for London. Mr. C. J. A. Meyer, F.G.S., whose intimate acquaintance with the Lower Greensand of Surrey is well known, has kindly furnished the following list of fossils obtained from the Nutfield Lower Greensand :-

Nautilus undulatus (Sow.) Panopesa Prevostii (D'Orb.) Ammonites Nutfieldensis (Sow.) Mytilus. " consobrina (D'Orb.) Lima Cottaldina (D'Orb.) " sp, Inoceramus sp, Pleurotomaria Anstedi (Forbes). Plicatula Carteroniana (D'Orb.) Natica sp. Pecten, allied to P. Milleri (Sow.) Yenus Vectensis (Forbes). near to. Trigonia ornata (D'Orb.) Janira Morrisii (Picket). " Archiaciana (D'Orb.) (P) Exogyra Tombeckiana (D'Orb.) " Vectiana (Lycet). Hernipneustis Fittoni (Forbes), Nucula, two or three species. common. Pholadomya Rauliniana (D'Orb.) Cone of Pinites. Panopeoa nana (Coquand). Fragments of Wood-abundant.