7°

FIELD MEETING IN THE RAVENSBOURNEVALLEY AT HAYES AND KESTON.

SATURDAY, JULY 1ST, 1933.

Director: ARTHUR L. LEACH, F.G.S.

[Received 4th July, 1933.]

A PARTY of twenty-five, including several visitors, met at Hayesstation at 3 p.m. On this, as on previous visits (July 8th, 1916,June 9th, 1928) the route chosen led by way of the gravel pitsin Tiepig Lane to West Wickham church (14th century brassand 15th century coloured windows) on an outlier of ThanetSand, thence up the steep escarpment of the Lower Eoceneformations above Coney Hall and over Hayes Common toReston Ponds, "Ccesar's Well" at the source of the Ravens­bourne, a pit in pebbly Blackheath Beds near Reston Mark,and, finally, through Holwood Park to Wilberforce Oak onthe edge of the steep descent into the valley of the River Cray.

This route permits attention to be directed to good instancesof geological structure made evident in surface features, to dryvalleys and a bourne course above the permanent stream inthe main valley, to the arrangement and constituents of thevalley gravel, to the relations of the present Ravensbourne andits tributaries to the main valley, to the Eocene escarpment, tothe plateau-like surface of the Blackheath Beds: and also tocertain hut-circles, earthwork enclosures and other features ofarchseological interest on Hayes Common.

The geological features were described in the Report of the1916 Excursion (see Reference): opportunities were taken todiscuss them again, and only two new points of interest nowneed be noted. In the Tiepig Lane gravel-pit a recent extensionof the workings west of the line of the bourne channel has re­vealed an uneven surface of Thanet Sand in the floor of thepit: on this lie hummocks of stony loam, apparently a soli­fluction sludge (not seen more than 2 feet in thickness), andon this sludge rests the normal coarse valley-gravel. Also, atrench recently cut across the meadow from the valley road upto West Wickham Church has passed through a coarse gravelbanked against the north-west flank of the outlier of ThanetSand and constituting, apparen tly, a terrace deposit at about230-250 ft. O.D. This terrace, which is also evident as a surface­feature, may be equivalent to the" Higher Terrace" noted byMr. Whitaker west of Bromley and at about 200 ft. O.D.

While the party were in Tiepig Lane pit Mr. A. S. Rennardcontributed some remarks upon the gravel, and remarked thatthe name" Beck," now applied to a tributary of the Ravens-

F!ELD ?lIEETIX G I }; TIlE HAVE XSBOUR X E VALLEY. 71

bourne, had no historical justification, the nam e " Beckenham "being derived from" Bekka, " a personal name and not from" Beck, " a stream. The erro r has, however, passed int o genera luse and is perpetuated up on maps.

After tea , at the Fox Hot el, Kest on , Mr. Kenn ard expressedthe thanks of the party to the Director , and thereafter themembers went to the source of the Ravensbourne, the spring at" Ca:sar 's Well " and Wilberforce Oak , returning across t heCommons to Hayes stat ion for the 8.27 train.

R EFEREN CE .L EACH, A. L . 191 6 . " Geologica l and Geographi cal Notes on the

Raven sb ourn e Vall ey ." P roc. Geol, A ssoc., 19 16 , vol. xxvii .,p . 139·