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EXCt;RSION TO R EIGATE.

S ATURDAY, JULY 2ND, 1 9 10 .

Directors : MISS M. C. C ROSFIE LD AND \Y_ W H ITAK E R, F.lZ.S. E x cursion Secretary: IVIARK " 'ILKS.

(R'!,or' by THE D IR ECTORS.)

REACHING R eigate in the afternoon, the par ty, nu mbering 40, which was a fairly large one considering th e weather, walked from the station westward for abo ut a mile to a pit close to the railway and on its northern side . T he section here was as follows: Clayey soil and wash. Gault. Grey clay, the bottom 216 ft. san dy, and with a great num ber of phosphatic nodules (some fossiliferou s), to the depth of abo ut 8 ft. Folkestone Beds. Brown sand to a co nsiderable depth. The junction shows the regular northerly dip, which carr ies the Folkestone Beds to a lower level underground in that direc­ tion, as is proved by a boring made no great way north ward, in which the bottom of the Gault was reached at a depth of 155 feet, whilst there is not much change in the level of the ground. Folkestone Beds were then pierced to a furt her depth of 1°5 feet. After shelte ring awhile from heavy rain the walk was continued northward to a pit in U pper Greensand, just eastward of the Colley Pits of the old six-inch Ord nance Map (Surrey 26), near which shelter was again taken in a shed, where one of the produ cts of the pit was studied (hearth-stone in the form of po wder). The section here has been a good one, but is now somewha t hidden, the stone of the Upper Greensand being worked under­ ground by mean s of head ings. At the top there is a good example of what Mr. F. ] . Bennet t has well named "Scarp­ drift, " an accumulation of flints, pieces of chal k, etc., which bas resulted from the downwash of the great slope just north. This is several feet thi ck. In October, 1897 , when the eastern face of this pit was fresh, one of the directors sketche d an interesting system of small faults in the stone, and the illustration, Fig. 2, is a reprodu ction of this sketch, the faults being marked by a dark layer. The sharp slope of the Chalk Escarpm ent was th en ascended, members scrambling up over the da mp and slippery grass in a pra iseworth y, though ungraceful manner, until a small chalk-pit (on the slope), new even to the Directors, was reached. The only notable th ing was the way in which more PROC. GEOL. Assoc. V Ol.. XXII. PLATE III.

FIG, I.-Berm ia a dilltt'iilJla L AMS X 8, EN CRUSTING Tere/'t',llula maxilla/a G REA T OOI.lTE,E NSLOW BRIOGE.

[Plt otl>by L t. Tr eacke r. FIG. 2,-Berellicm archiaci HAIME X 8, E NCR USTING Tenct'alllia max i//ata. GREAT OOLTTE.E NSLOW BRIOGE. EXCURSION TO REIGATE. 7 or less vertical cracks had opened up near the surface, at the lower part, as if in preparation for a fall. K S.

FIG. 2.-FAULTS IN THE UPPER GREENSAND NEAR REIGATE. - W. Whitaker.

The ascent was then continued to the higher pit, near the top of Colley Hill, and just west of the Queen's Park, Reigate. This pit was the chief object of the excursion, and here the party had its final wetting. The chalk is curiously broken up and infiltrated with sand (apparently of Eocene origin) in a very irregular way, cracks and crannies being filled with the invading material. But some of the openings in the chalk have been otherwise filled, by masses of crystalline calcite, more or less globular, with radiating crystals. Calcite is of common occurrence in most limestones, but, strange to say, it is not so in the Chalk, and one of the Directors, who had probably been in as many chalk-sections as anybody, had no recollection of ever having seen masses of calcite in the Chalk before entering this pit two years or so ago, and moreover had heard of very few such occurrences. Why so common a mineral as crystalline calcium-carbonate should so rarely occur in a formation that almost wholly consists of amorphous calcium-carbonate, is a point left for con­ sideration. The view from the hill-top over the Vale of Holmesdale and the Weald was much admired (as also were the various storm­ clouds, at a distance), and the connection of the physical features with the geologic structure was pointed out. Passing through the Queen's Park eastward the slope was gradually descended and the party was most hospitably enter­ tained by Miss Crosfield at Undercroft. Refreshed by their meal; the party walked south-eastward to Wray Common, on the Gault, which here has a slight escarpment-feature, and then down The Way (formerly Oak Road), to the large sand-pit on the eastern side of that Jane, and just north of the railway, which gave the following section: Irregular clay, partly reddish, partly grey, and clayey green-sand, a few feet. Folkes/one Beds. Light-coloured sand, at the top ferruginous, and, at one part, with an irregular band of ironstone running across the current-bedding. Lower down there is much white sand. 8 EXC UR SION TO AI{ LES£Y AND LETCHWORTH.

The clay at the top may be largely a wash of the Gault, but the clayey greensand looks like the usual base of that formati on. If it should be so the absence (or all but absence) of phosphatic nodules here is remarkable, and contrasts with what was seen in the first pit visited. The walk was then conti nued to Redhill, where the party entrained. REFERENCES . Ordnance Survey 3fa p, Ne w Series, Sheet 286. Geological Survey 3Iap, Sheet 8 ( Drift Edition).

EXCURSION TO ARLESEY AND LETCHWORTH, JULY 9TH, 19IO. Director : The Presidellft WILLIAlII HILL, F. G.S. E xcursion Secretary: MARK \\'ILKS.

(R/port by T HE D IRECTOR.) APARTY of twenty-two arrived at the Three Counties Station at Arlesey a little before 3 o'clock, and proceeded to the brick­ works of Messrs. Beart & Co., close by. These works have been established for fifty years and more, the clay used is the upper part of the Gault and a deep excavation has been made in it (Plate IV, Fig. I). On the east side of the pit about loft. of the over­ lying Chalk Marl, with the Cambridge Greensand at its base, is seen. The section had altered little since the last visit of the Association, in 1 900. The Director pointed out the Cambridge Greensand, a calcareous marl abou t z ft. thick, full of glaucon ite grains and phosphate nodules or "coprolites," resting on the uneven and eroded surface of the Gault. At one time it was regarded as the equivalent of the upper Greensand, but it is really the basement bed of the Chalk Marl. It extend s from Harlington, about six miles west of Arlesey, to Soham, where it passes beneath the fens. The nodu les, most abundant in the lower part of the bed, were the pho sphatised remains of shells, teeth and bones, derived from the Upper Gault, the commoner species being those found in the Upper Gault of Folkestone. Th e nodules were very rich in phosphate, and were at one time used extensively for the manufacture of phosphate of lime for agricultural manure ; the supply, however, in this locality is exhausted. The fauna found in the bed; but derived from the Gault, is a large one, two-hundred and ten species being recorded by 11r. Jukes-Browne. There is also a large group of fossils