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110 EXCURSION TO FLITWICK AND SILSOE. SATURDAY, APRIL 15TH, 1905. Directors: JOHN HOPKINSON, F.L.S., F.G.S., Assoc. Inst.C.E., and JAMES SAUNDERS, A.L.S. Excursion Secretary: W. P. D. STEBIlING, F.G.S. (HI}"'" 6)' Mr. HOPKINSON.). IN the journey from London, after leaving Middlesex for Bed­ fordshire, the whole of the Upper Cretaceous strata represented in the section was passed through, and in the cuttings of the Midland Railway between Chiltern Green and Charlton the three SECTIOX, :-;EARI.Y NORTH AN D SOUT H, FRO~( C AST l.E IIILL, CLOPHILL, TO W AR UE:-; IlIl.L, :-;EAR L UTON.-.7. lIoplimon. Barton Hill,. G " i . • H Orizontal scale I in. to 2 miles ; vertical scale I in. to 2,000 [to I. upper Chalk. 5. Lower Chalk. Z. Chalk Rock. 5a. T otternhoe St one. 3. ~ I id dl e Chalk. 6. Gault. 4. Melbourn Rock. 7. Lower Greensand . hard beds in the Chalk-the Chalk Rock, the Melbourn Rock , and the Totternhoe Stone-were seen. On the plain beyond, the Gault was traversed, and in approaching Flitwick the outctop of a formation better withstanding denudation-the Lower Greensand -became evident from the rising ground. The Chalk on the south, attaining a height of 800 ft., and the Lower Greensand passing through the centre of Bedfordshire, rising to 500 ft., form the two main ranges of hills in the county, and the object of th is meeting was to examine sections of the latter formation. A party of sixteen assembled at Flitwick Station. A good section of the Woburn Sand, with its variously-coloured beds, from white to red, was seen near the railway, on the west of the line; its position appears to be about the middle of the Green­ sand. On the opposite side of the line, north of the station, the ground is a little higher, and the highest part is capped by a bed of gravel and sand (now being removed for road metal and garden­ paths), containing boulders apparently derived from the higher EXCURSION TO FLITWICK AND SILSOE. 111 part of the Greensand, which has here been eroded away, and rocks of foreign origin drifted from Palseozoic beds in the north. Descending into the valley of the Flit, other sections of the Woburn Sands were seen, and the party then divided, the walkers, under the guidance of Mr. Saunders, crossing Flitwick Moor to Flitton and Wardhedges Quarry, Silsoe, and the cyclists, con­ ducted by Mr. Hopkinson, taking the road through Greenfield and Flitton to the Castle Hill Quarry, Clophill. Mr. Saunders reports: "The walking party visited the source of the Flitwick mineral springs. Most of the members tasted the water, which had been filtered, and it was found to be strongly impregnated with iron and vegetable acids. It has powerful medicinal properties, chiefly tonic and astringent. After passing Greenfield Mill the course led by the side of the River Flit. It was noticed from the appearance of the water that it contained iron, which was being deposited on the pebbles in the brook. It was very unlike the bright, sparkling streams which pass through the chalk district of the south of the county." On their way to Castle Hill the cyclists visited Flitwick Quarry, where the "Carstone" of the Lower Greensand is exposed. This is on a higher horizon than the Woburn Sand, and, like it, shows current-bedding, or perhaps in its case more correctly false-bedding. The section at Castle Hill exposes the same and the succeeding beds to the highest portion of the Greensand seen in this neighbourhood. It is of special interest, as it shows 10 ft. of dark-coloured clay, called by the workmen "black clay," to distinguish it from the ., blue clay " of the Gault, occurring in three distinct beds of about equal thickness with thin layers of sand between them, dark-red carstone being above the clay, and light-coloured sand beneath it. This black clay occurs at Shefford, to the east, where it has thinned to one foot, but it is not known to occur elsewhere. It is used by the workmen at the brickfields at Lower Gravenhurst, which would have been visited had time permitted, to mix with the clay there obtained from the Lower Gault. The face of the quarry in which the layers of clay are seen, looks towards Castle Hill, and does not show cross-bedding, but behind these workings there is another quarry showing the sand and carstone apparently without the clay, and very much cross-bedded. In it, capping the Greensand, there is a thin bed of chalky boulder clay, in which drifted specimens of Gr..vphrea incurua were found. The " doggers" and harder layers in the Greensand are here being quarried for the new waterworks at Biggleswade. The two parties then joined forces at the George Inn, Silsoe, where a good tea was provided, after which the walkers returned direct to Flitwick, and the cyclists visited Wardhedges Quarry, an extensive excavation in the carstone, showing well the doggers of harder rock which owe their hardness to the infiltration of iron, Carsrone quarry, ~:\~ ' in Lower Greensand. in Lower Greensa nd. I I ... ... '" ~ o c:: :0 sUl Z C5 '%j to' ::l ::6 Gravel with n Boulders. Brickfields, ~ Woburn - in Lower :.­ Sand and Gau lt. Z Gravel. t1 ~ to' Ulo t'J J. I II JI ~ ~ .J . Sand pu s, "G1old Carsrone qua rry L- ~ in Woburn Sand. Mine." in Lower Greensa:,d;C=--- iJ'1.. War d hedges. Scnle : One inch eeone mile. M AP OF THE CO UNTRY AROUND SILSOE, BEllS. EXCURSI ON TO FLITWICK AND SILSO E. 113 and also fine examples of cross-bedding. This quarry had been previously exami ned by the walking party. T he cyclists then visited the site of the historical " gold mine " in Gold Close, Pullox Hill. Some account of this mythical mine had been given by Mr. H opkinson after tea, before th e party separated. It is well known to the villagers-app arentl y by traditi on-he had found on inquiry, that a furnace had been set up and gold was said to ha ve been obtained, and potices of the occurrence of gold here occur in various works. Calvert, in his Gold R ocks of Great Britain (r 853) , mentions it on the authority of Waters' Com. pendium of British .lI1ining (r 843), where the following passage occurs: " About r60 years since, two gold mines were stated to have been discovered ; one at Pollux Hill, in Bedfordshire, and the other at Little Taunton, in Gloucestershire. The Society of Mines Royal seized them, and granted two leases of them to some refiners, who extracted some gold; but th ey did not go on with the work, as the gold sometimes would not repay or requite the charge of separation. though sometimes it did." Watson's quotation is from Abbott's Essay 011 the Mines ofEn.~/and. This was about the year r 640 ; in the eighteenth century th ere was a report that gold had again bee n found near Ampthill, and it see ms to have caused some excitement. Pennant, however, states tha t it " turn ed out noth ing but talc." In the original Ordn an ce Survey Map the name of the meadow, "Gold Close," is not only given, but the actual site of the mine is located by the words " gold mine," while in the new series both these indications of the site are omitted, a revision much to be deprecated. The cyclists rejoined th e walkers at Flitwi ck in good tim e for the appointed train. The weath er was perfect, and the country, which in the neighbourhood of Clophill is very pretty , had the freshness of the spring with a foretaste of the leafiness of the summer. REFERENCES. O rdna nce Map r-in ch, New Survey. Sh eet 220. Geo logical Survey Ma p. Sheet 46, N. E ., Drift . 1720. Cox , REV. T .-Magna B ritannia, vol. i, p, 150. 1738. ANON.-Atlas Geograpnicus, vol. i, p. ISO. 1764. ., -England I/lust"att rl, vol. i, p. 4. 1778. PENNANT, T .-Tours 11/ WaIlS, vol. i, p. 66. 17 ~9. CAMDEN,W.-Brit'lnnia, vol. i, p . 330. (And in other editions.) 1818. DODD, S.-Account ojllu Town oj Woburn, p. 129. 1833. ABBOTT, G.-Essay 0 1/ Iht Mints ofEngland, p. 203. 1843 WATSON, J. Y. - Compmrlium of British Milling, p. 60. 1853. CALVEHT, J.- Gold Rocks ot"Gnat Britain and Ireland, p. 101. 1876. HILLHOUSE, W.-" S urfa ce Geology and Physical Features of Bed fords hi re." Tran s. B eds, Na t. Hist, Soc. for 1875-76, pp. 83-96. 1904. H OPKINs0N, J., and J SAONDERS.-" Ge ology." Victoria History of Ih~ County ofBedford, vol. i, pp . 1-32. (S ilsoe and Clop hill, p. 1I ; Fl it wick Moo r and Pullox Hill, p. 31.).

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