ANCIENT EARTHWORKS be manifest that there is nothing exceptional (as regards the space allowed) in the examples here given. The pit shown in fig. 8 is near the eastern margin of Joyden's Wood. Its position is about 460 yds. due east of the ' summer house ' marked on the six-inch Ordnance map. Not being a member of a compact group, but one of a number of single pits scattered about Joy- den's Wood, the makers have evidently excavated simply as their convenience suggested, unrestricted by those rules for the common advantage enforced in Stankey and Cavey Spring. TiHimni cf ctoir root . . . , 9tAt Fig. 7. Cavey Spring Pit. r 80 n . Fig. 8. Joyden's Wood Pit. Kind j acalt So rt^otit Inch. Fig. 9. Hangman's Wood Pit. While Bexley is certainly the best centre in Kent for the exploration of deneholes, as the one spot where they may be studied both scattered and in groups, there is some evidence for their existence at Eltham and Blackheath. For deneholes in those localities, if ending in the chalk, must not only be considerably deeper than any hitherto mentioned, whether on the Kentish or the Essex side of the Thames, but must have been constructed under difficulties arising from the geological structure of the ground, absent elsewhere. On I March, 1878, Mr. W. M. Flinders Petrie read a short paper at a meeting of the Royal ArchcBological Institute (which was afterwards published in the Archceological Journal) on a remarkable shaft and subterranean chamber lately discovered in Eltham Park, the seat of Mr. T. Jackson. From this paper we learn that, in order to remedy a considerable leakage in the water supply, workmen were ordered to trace the course of the water that escaped. It was found to run into a disused brick drain, which ended at the top of a deep shaft. The ground above the shaft was then broken up, and the crown of the arching over it appeared at only 6 in. below the surface. The shaft was about 100 yds. from the house, was 140 ft. deep and over 4 ft. wide, and ended in a chamber cut in the chalk, which was about 30 ft. by 50 ft., and 9 ft. high. The roof was flat, its position being determined by the existence of a band of flint, and the chamber was supported by three pillars of chalk in its centre. The shaft was carefully lined as far as the chalk, the upper 75 ft. being lined almost entirely with bricks, below which 40 ft. were lined mainly with blocks of chalk, and the lowest 22 ft., being in the chalk, were unlined. But there were six courses of chalk in the brickwork, and eight courses of brick in the chalk. At some date much later than that of the original construction of the shaft and chamber a drain had been made leading to the shaft, and the chamber below had been used as a cess- pool. From the quantity of deposit at the bottom of the chamber, Mr. Petrie thinks that the drain probably ran into it for at least a century, perhaps two or three centuries. As regards the age of the shaft and chamber, the bricks in the shaft do not, in his opinion, offer any con- clusive evidence, and he is equally doubtful as regards the objects of the makers of the shaft and chambers. However, it seems clear that they could hardly have been the mere extrac- tion of chalk. Consequently, it seems to me that as this Eltham pit must have been made for the sake of the chamber excavated, and not for that of the material extracted, it belongs to the denehole class. The strata above the chalk in the denehole shafts of Cavey Spring, Stankey, or Hangman's Wood consist of Thanet Sand with an occasional capping of gravel at the surface. At Eltham the following section, which is that of a well at Eltham Park, a few yards southward of the denehole, is given by Mr. W. Whitaker {The Geology of London and of Part of the Thames Valley, il. 71). 451
