Excursion to Charlton and Plumstead
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EXCURSION TO CHARLTON AND PLUMSTEAD. JULY 13TH, 1901. Directors: THE PRESIDENT (W. WHITAKER, F.R.S., F .G.S.), and T. V. HOLMES, F.G.S. Excursion Secretary: W. P. D. STEBBING, F.G.S. (Report by T. V. HOLMES, with Notes b)· THE PRESIDENT.) THE party arri ved at Charlton Junction railway station about 3 p.m., and, turning eastward, passed by way of Cedar Grove through the old chalk- and sand-pit, which has been the scene of some of the earliest excursions of the Association. This pit attained its greatest size some years ago, and, from not having been recently worked, its sections are not so clear as they once were. It has not, however, been occupied by the builder to anything like the same degree as Loampit Hill, Lewisham (another spot once much favoured by geologists), and still shows the dip of the Chalk and overlying beds very clearly. East of this old pit the party entered that of Mr. Woodgate (who had kindly given permission for the visit), which is Oil the western side of the promontory, ranging nearly north-west and south-east, between the old chalk-pit westward and Maryon Park eastward. The sections here were in excellent condition, showing the top of the Chalk in the lowest part of the pit, the whole of the Thanet Sand, and the overlying Woolwich Beds and BJack heath Pebble Beds. The President, on calling attention to their details, also pointed out how strangely mixed together were the fragments of the upper beds formi ng the talus on the slope of the hillside. The party then made their way to the top of the hill, pau sing on their route to look at the lower beds of the Woolwich Series, which had been worked back from the top of the Thanet Sand. On the top of the hill, ridges, which had once formed the western side of an old prehistoric camp, became visible. The greater part of this camp must have disappeared as the old chalk- and sand-pit, eastward, now Maryon Park, was enlarged, the ramparts at their south-western angle clearly pointing to its former extension eastward. Mr. Holmes remarked that he had looked into that part of the new edition of Hasted's" History of Kent," which comprised"The Hundred of Blackheath" (additions by Streatfield and Larkin, edited by Drake. London, 1886), with the view of learning something about this camp. On p. J 23 he found :- "Mr. Jones built a house in the centre of the old Roman encampment that overlooks the lower road to Woolwich; a small mass of the brickwork remained in 1837 on the brink of the sand- EXCURSION TO CHAR LTON AND PLUMSTEAD. 183 pit, which has destroyed half of the earthworks. A description of sand is there found which sold for a guinea a cubic foot, and the sides of the pit exhibit the geological strata, one of which is of shells, very distinctly." On p. 134 was a note saying, " For notice of ancient earth works at Charlton, see Archseol, Cantiana XIII, 15. with a Plate." On referring to the volume in question (1880), he found " Notes on Kentish Earthworks," by W. M. Flinders Petrie, a very short paper, in which more than fifty Kentish earthworks are briefly noticed. The plate shows the camp much as it now is, and there is a note stating : "Charlton. The banks along the side are on the slope of the hill below the edge. The faint ditches in the area are singular." The camp is shown on the Ordnance Map (6 in. to the mile). Probably it is British, not Roman. The shell-beds of the Woolwich Series were most easily inspected by a descent of a few feet on the easterly, or Maryon Park, side of the hill, the platform in the pit at the top of the Thanet Sand bein g too low for that purpose. Reascending to the top, many shells were seen in the BIackheath Pebble Beds, where they had been worked for gravel at the south-western angle of the camp. The shells much resembled those of the Woolwich Series. Perhaps the chief point of interest in conn ection with them was the ir existence in the pebble-beds in irregular patches, sometimes only three or four feet beneath the surface. The shells, however, seem to have been protected here and there from the dissolving action of rain by a tend enc y to the cementing togeth er of the pebbles by iron in small irregular patches. After tea at Old Charlton, it was ann ounced that Mr. C. H. Grinl ing, of Woolwich, had writte n to the Secretary of the Asso ciation, Mr. Emary, kindly menti oning the existence of some sections in a new road at the north-eastern corner of Plumstead Common. Most of the party decided to visit them before returning to London, and took train for Plumstead from Cha rlton Station. The road in which the sect ions were seen is incomplete, and may be reached b) the footpat h connecting Wickham Lane, close to its Plum stead end, with the north-eastern corner of Plumstead Common. On ascending, in a south-westerly direc tion, towards the Common, the top of the Thanet Sand, much covered by talus, formed the most easterly section in the new road. Higher up the hillside were seen the Woolwich Beds. 'I'hey consisted of sand and pebbles at the base, above which is whitish sand, of which twelve feet or more were visible. The junction between this sand and the overlying shell beds was somewhat irregular. The shell beds (rather thin) consisted of a lower sandy bed, very full of Cyrena, and an upper one with fewer shells, more clayey and of a darker colour. This clayey shell-bed was cut off south-west by the BJackheath Beds. Above EXCURSION TO PULBOROUG H. the Woolwich shell-beds appeared the sands and pebbles of the Oldhaven, or Blackheath, Series, which seemed to be slightly un conformable to the Woo lwich Beds. Nearer th e top of the hill th e Blackheath Beds only were seen, consi sting of sands with irregular mass es of pebbles at top and bottom. Some of these pebble bands consisted mainly of stones much ab ove th e average size, others of stones unusually small. REFERENCES. New Ordna nce Map, Sheet 271. Pr ice I S. Geo logica l Survey Map , Sheet I, S.W . (D rift Edition). 1889. WH ITAKER, \ V.-" Geology of Londo n." ' -01. i. i~fml . Geo]. SI/1 '1·e)'. 1895. HOLMES, T. V.- " Ex cursions to Ch arlton." P roc, Geoi. A ssoc., \'01. xiv, p. III. EXCURSION TO PULBOROUGH. S AT UR D AY , J U L Y 20TH, 1901. Director : J. VI NCENT ELSDEN, B.Sc., F.G.S. E xcursion Secretary: W. P. D. STEBBl NG, F.G.S. (Report by THE D IRECTOH.) ASSEMBLI NG at Pulborough at noon, the party proceed ed to exam ine the Lower Gree nsand bed s in de scending orde r. In a roadside sect ion near the railway arch, close to th e railway station, the base of the Folkestone Beds was first examined. The ferru ginous sands are here covered with a thin bed of river gravel, containin g rolled pebbles of flint, chert, and iron ston e. Ascending th e hill by the station, a fine exposure of the Sandgate Beds was then visited. This sec tion has been recently opened for brick making, and shows about ten feet of bluish clay resting upon the same thickness of ferrug inous sand. This formatio n is probably better developed in the neighbourhood of Pulborough than at any other part of the Weald en area, and the total thickness of the beds is estimated at 100 feet. The clays differ from the Gault, for which they were onc e mistake n, in being of a more sandy nature, requiring no further admixture for the manufacture of excellent bricks. In the sands beneath the clay, ironstone nodules are plentiful ; but there is no record of fossils having been found in th em at this spot. A layer of iron grit occurs at th e base of the clays. The party th en walked toward s the village, and, ascending th e hill towards the church, noticed that the road cutti ng exposed the same beds as were seen in th e brickpit..