A HISTORY OF KENT 



been kept in repair and utilized down to a comparatively modern period ; while at Black- 

 heath the positions of old shafts, with presumably chambers at their bases, have hitherto been 

 revealed only when the falling in of the long disused and neglected shafts, through the action 

 of the water concentrated at the base of the Blackheath pebble beds, has at once both choked 

 up shaft and chamber, and at the same time indicated their position by the subsidence at 

 the surface resulting from their destruction. 



Before leaving Blackheath it seems to be worth mentioning that Mr. Spurrell alludes 

 to, but does not quote, the following account of a subsidence at Blackheath in 1798. It 

 appears in the Gentlemaii's Magazine for 1798, p. 1,078 : ' A singular accident happened last 

 week at Blackheath. As a farmer and his son were conversing together in a field where a horse 

 was feeding, on a sudden the animal sunk into the earth (hind feet first) to the depth of 15 ft., 

 out of which he was dug, crushed to death. The cavity was only just sufficient to admit his 

 body, the surrounding soil remaining firm.' This account certainly suggests a subsidence 

 similar to the two deeper ones on Blackheath. But it seems to have taken place in some field 

 near the open common known by that name, not on the common itself. 



Much careful exploration will be necessary before any definite knowledge can be ob- 

 tained as to the comparative antiquity of deneholes, and the periods not only of their con- 

 struction but also of their utilization. We have seen that the pair of shallow deneholes near 

 Crayford, described by Mr. Spurrell, dated from the Neolithic period. Then the exploration 

 of the deneholes of Hangman's Wood by the Essex Field Club in 1884 and 1887 made it pro- 

 bable that they originated in post-Neolithic but pre-Roman times, and were in use throughout 

 the Roman occupation and possibly later. On the other hand, the remark of the young 

 labourer's father at Billericay in 1 87 1 that an excavation like a gravel-pit was ' a denehole 

 which had caved in,' decidedly suggests that, in some form, they must have been made and 

 used, in districts where they had once been in demand, down to a comparatively recent period. 

 Probably the circumstance that they were secret storehouses, etc., tended to a reticence as 

 to their existence on the part of the agricultural population using them, which may explain 

 the absence of any modern antiquarian allusions to them as not only once used, but as still 

 found useful locally.^ 



APPENDIX II 



ON THE EMBANKMENTS OF THE THAMES IN KENT 



The embankments of the Thames below London as seen in their entirety present an 

 appearance of completeness which somewhat exaggerates their importance. They are the 

 result of the slow and creeping work of centuries. When the country was occupied by the 

 Romans the low lands of the Thames were dry, that is not invaded with salt water. The 

 river was fresh and very shallow, with meandering streams from the uplands adjacent. Large 

 trees hundreds of years old, of such kinds as we have now growing, covered the bottoms and 

 spread over the area of the present marshland, and everywhere are found Roman remains, 

 pottery, and flint and chalk used in building. This level, which is a little below the Ordnance 

 datum, may be called the Roman level. It is scarcely probable that any banks were needed 

 here and none have been found of the Roman period ; nor can there be found any places 

 indicating the least connexion between a Roman site and an embankment of any date. At 

 the termination of the Roman period or soon after there came an irruption of the sea, which 

 overthrew the trees and buildings and deposited over all grey tidal clay with salt water shells. 

 The river became an estuary and has remained so ever since. The invasion of the sea was 

 sudden, probably in the nature of a catastrophe, and accomplished the destruction of exten- 

 sive settlements on the low shores and numerous islands eastward of the Medway mouth. 

 This change was probably caused by a small subsidence of the land accompanied by so-called 

 tidal waves. There are no banks for keeping out the tide known to be of Saxon date, except 

 those of Littlebrook and Sittingbourne, and these were hythes of small size placed to haul up 

 ships in winter and guard off storm floods and foes. To two of these can be assigned some- 

 thing of a date, viz., Littlebrook, which is mentioned as a celebrated place in a charter of 



1 As it has been suggested that the caves at Chislehurst are of the nature of deneholes, it may be 

 well to mention that there can be little doubt that they are workings in the side of the hill for chalk, 

 and are probably of a comparatively late date. 



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