Some Early Chalkwells in N. W. Kent

SOME EARLY CHALKWELLS IN N.W. KENT By JOHN E. L. CAIGER THE custom of marling or chalking the land in an endeavour to improve poor or impoverished soil has been known and practised since very early times. Heavy clay lands and sour peaty soils considerably benefit from the addition of chalk, whilst friable soils generally benefit by the addition of clay and chalk, i.e. marl. The Belgae were credited by the elder Pliny (A.D. 70) with the art of using chalk for agricultural purposes, which he states they obtained from deep wells.1 Old Norman leases sometimes contained covenants to ensure that marl was applied to the land. Agricultural writers in the seventeenth century such as Gervase Markham and Walter Blith2 advocate the application of chalk for soil improvement, the latter writer uses the term " chalking ". The practice of sinking chalkwells, or draw-pits as they were sometimes called, to obtain agricultural chalk can be said to have reached its peak during the eighteenth and nineteenth centuries when woodland was being extensively grubbed up by farmers eager to place more land under cultivation for oats and root crops. Chalk was applied to this newly-tilled heavy soil on a most lavish scale, amounts between 40-80 tons per acre being quite commonly used quantities. The greater proportion of the chalkwells noted in Kent, Surrey, Berks, and Hants, were sunk during this latter period, by farmers who required large quantities of chalk for dressing their fields. When the land bears a considerable upper layer of clay-with-flints the chalkwell method of extracting chalk has much to recommend it, since the minimum amount of superincumbent clay need be removed before the underlying chalk is reached. Amongst farmers there was a strong preference for chalk obtained from a depth, it being asserted that this type of chalk was " fatter " or " stronger " than surface chalk and had the advantage that it readily powdered under the action of winter frosts. The traditional time to mine and spread it over the fields was late Autumn. It is recorded from several sources3 that these chalkwells were dug by itinerant bands of men who followed it as a trade during the latter part of the eighteenth century. 1 Lib. XVII. (8). 2 Survey of Husbandry, 1649, 58. 3 A Synopsis of Husbandry. John Bannister, XVIII, 46. 81 9 SOME EARLY CHALKWELLS IN N.W. KENT A method employed for extracting chalk in Hertfordshire1 in 1794 was briefly as follows : A spot was fixed centrally to the area requiring chalking and a shaft 4-5 ft. diameter was sunk through to the chalk bed, perhaps 20 ft. beneath the surface. At the base of this shaft three separate horizontal headings or adits were driven by the pitman until enough chalk had been hewn to dress an area of approximately 6 acres. The men by custom would distribute the chalk over the surrounding land to a maximum distance of 330 ft. from the chalkwell but insisted on opening a new shaft if a larger area required chalking. Three men formed the team. The pitman dug the chalk and his two companions wound it up the shaft by means of a windlass and then distributed it from a cart over the field. The quantity of chalk used approximated to 60 tons per acre, hence by this recorded method each chalkwell yielded about 360 tons of chalk. A noteworthy fact concerning certain chalkwells which have been examined by the writer in N.W. Kent, namely at Downe, Cudham and Birchwood is that they show a marked uniformity of pattern and size with those described above. From the typical wages paid for this class of labour in 1790 a chalkwell cost the farmer about £10 but it yielded sufficient chaUc to dress generously a six acre plot. Due to the very heavy expense incurred when land required chalking, farmers preferred to give their fields one heavy dressing of chalk at intervals of twenty years or more, rather than smaller amounts spread more frequently. Owing to high cartage costs and poor roads it was not an economic proposition to excavate the chalk very far away from the field that required dressing. During the evening of September 5th, 1958, a severe and heavy rainstorm revealed the presence of many partly fiUed up shafts and underground excavations in the Dartford and Gravesend districts. In every case which the writer investigated the existence of the caves and shaft was unknown to the respective landowners and was only revealed by storm water washing away the shaft filling into the chambers below. Of the several subsidences inspected, four, namely three chalkwells and one denehole, are worthy of description. THE DARENTH PARK HOSBITAL CHALKWELL This subsidence was in the grounds of the above hospital arid occurred within 30 ft. of one of the hospital blocks, location, N.G.R. TQ571730. A shaft 5 ft. diameter had appeared at this spot which descended to a depth of nearly 20 ft., and at the base three chambers had been hewn leading off horizontally. 1 Report on Agriculture of Hertfordshire. B.O.T. 1804, 168. 82 SOME EARLY CHALKWELLS IN N.W. KENT A CHALKWELL AT GRAVESEND. ^ ' SANDYLOAM&CLAY BRICK ARCH 17* C PARTLY DESTROYED, xr, _ ENTRANCE SHAFT 5 OlA. CHALK OPENING TO WELL N« 3 AVERAGE MAN.^ DEBRS SPOL FROM BUILDING SITE SECTION A-A. CHALK PILLARS WELL CHALK PILLAR UNDERGROUND PLAN •^^•^^•^^^^ HEIGHT OF. SCALE IN FEET. J.E.L. CAIGER.. Jan.1. FIG. I. 83 SOME EAARLY CHALKWELLS IN N.W. KENT I I.I I 11,1 Scab, of Feet. Chalk Stoneware f>ip& crossing roof. DARENTH PARK HOSPITAL CHALKWELL. F/G.2. iChafk O 10 In I I I I I T ri Sea ft. of F