SimMedieval

MEDIEVAL INDUSTRY

INDUSTRIAL DEVELOPMENTS IN MEDIEVAL DARTFORD

Although medieval Dartford’s fortunes were largely bound-up with agriculture, trade and commerce, there were a few minor developments of an industrial nature in what is often thought to be a pre-industrial age.

After the Norman Conquest, simple machinery was developed to take the drudgery out of back-breaking repetitive tasks. Dartford’s fulling mill is a good example of this kind of development. The extractive industries also became important in providing raw materials for the building trades and for the improvement of land. Milling, fulling, lime burning, tile making, chalk mining, and possibly tanning, were represented in medieval Dartford.

MILLING

Of all the machines in use, the mill was the most widespread. It turned wind or water power into cost-effective energy for grinding flour, tanning leather, processing cloth and a variety of other tasks. The mills played an important economic role in medieval society. Although the initial investment in mill machinery and plant was expensive, the long-term return in profits was excellent. It is not therefore surprising to find that important institutions such as the Church and the Knights Templars owned mills on the River Darent either in or close to the town. The River Darent provided a constant and reliable flow of water ideal for driving rudimentary mill machinery.

Early records show that there were a number of mills in medieval Dartford. The earliest reference to a mill is in Domesday Book which interestingly implies that there had been a much earlier mill in Saxon Dartford.

In 1221, William, prior of Rochester, granted to Alan Martel, prior of the Knights Templars, half an acre of land in Dartford lying by the stream which flowed down from the mill south of Holy Trinity church which the Templars owned. This was probably the mill, which King John granted in 1217 to Michael de Wallensi. At this time the mill was valued at 100 shillings a year. By 1253, the mill belonged to the bishop of Rochester. In 1299 the mill was known as Orchard’s Mill and was privately owned.

A flour mill and corn mill were also located on the River Darent, based in the manor of Portbridge or Bignores (close to modern-day Powdermill Lane). These mills were later owned and leased by the prioress of Dartford.

FULLING MILL

From the twelfth century onwards, wool was the staple industry of England. The production of good-quality woollen cloth for the home market began to expand in the fourteenth century. The home-based woollen industry was made possible, at least in part, by the introduction of water-powered fulling stocks. Fulling was a vital process in the production of cloth, converting a relatively loosely-woven fabric into a close-knit one, by soaking it in fresh clean water and fuller’s earth, and then pounding it by foot (rather like treading grapes). Fulling stocks, heavy wooden hammers driven by water wheels, achieved the same result with less labour and greater efficiency.

During the reign of Henry VII (1485-1509) a fulling mill was constructed on the River Darent at the foot of what is now East Hill close to the town centre. The fulling mill was used for the thickening and cleaning of cloth. The woven cloth was first washed with potash. Potash was similarly used for woollen cloths, but fuller’s earth or pig’s dung and stale urine continued to be widely used as a more economical alternative.

Woollen cloth was fulled to thicken it and give it a firm structure. Heavy hammers were raised and allowed to fall on the cloth bundled in a large trough below. The heavy oak hammers pounded and softened the cloth; they were so shaped that each time the cloth was pounded it rotated a little to ensure uniform action and to prevent damage.

After fulling the cloth was dried on tenter-frames. At Dartford, the field adjacent to the fulling mill was known as Tenter’s Field. This was where the large tenting frames used for stretching and drying cloth were sited. The tenting frames consisted of upright wooden posts with a fixed upper rail and a lower rail whose position was adjusted by pegs or wedges. Both rails were fitted every two or three inches with tenter-hooks, L-shaped double-pointed nails. The hooks in the top rail pointed upwards and those in the bottom rail downwards. The wet cloth was hooked by its edges to both rails and the lower rail adjusted to draw the cloth tight and of even width.

LIME BURNING

Lime (calcium oxide) was used for the manufacture of mortar and also as a fertiliser. It was discovered in medieval times that lime improved soil structure and neutralised excessive soil acidity, leading to increased crop yields. For lime-burning, only broken chalk was required; this was usually quarried right next to the lime-kiln site.

Lime was obtained by burning chalk in a specially constructed lime-kiln. Most medieval lime-kilns were 10 or 12 feet in diameter, walled round to three or four feet high, with draught tunnels at the base. Inside the kiln a fire of brushwood was made and broken chalk added to alternate layers with the fuel to the top of the wall, and this was continued up to make a heaped top. The whole was covered with slabs of turf and left to burn for a week or two.

By the thirteenth century, lime-kilns were being built with a tapering bowl-shaped interior with one or two wind tunnels set into the base. Wood was the main fuel used in lime kilns, but was gradually replaced by coal after c.1500. The earliest written reference to this industrial activity at Dartford dates from 1445. It is likely that in early medieval times, Dartford’s lime kiln existed to supply the building trade.

A lease drawn-up by the churchwardens of Dartford in 1445 granted permission to John Grey and John Vynor of Dartford to build a new lime-kiln at Lurching-hole on Chalkdale (currently the site of West Hill Hospital). The new kiln would be of sufficient capacity to produce eight quarters of lime at one firing. The initial lease was for four years, but lime-burning continued on this site for another three centuries. Lime burning generated unpleasant fumes and smoke. This explains why many lime kilns like the one at Dartford were sited well away from the town centre.

LOAM PITS

Dartford’s loam pits were sited just off the road between Lowfield Street and Wilmington. Dunkin, Dartford’s nineteenth century historian, reports that in ancient times when most of the houses in Dartford were constructed of timber framework and covered with plaster, the inhabitants were allowed the valuable privilege of digging loam in the loam pits freely. Two acres of land had been given to the parish for this purpose as early as 1344 by Richard Sone of Dartford. Loam deposits were useful for the manufacture of bricks, tiles, mortar and plaster.

CHALK MINING

The area around Dartford is characterised by man-made structures known as Deneholes. These features consist of a well-like shaft dug through the strata into the chalk. Deneholes were dug in medieval times as a means of extracting good-quality chalk, which could be spread on local farmland to improve the quality of the soil. This process of fertilising soil was known as far back as Roman times. Chalk was also used for building purposes.

The shaft of thedenehole had foot and hand-holds cut into it to enable descent and ascent by the medieval chalk miners. On reaching the chalk, the miners excavated up to six chambers radiating from the bottom of the shaft. Picks, shovels, baskets and ropes were the only tools available to these early miners. Deneholes with shafts up to 70 feet deep have been found in the Joyden’s Wood area, in Darenth Woods, and elsewhere. They are unique to North Kent and South Essex. Archaeological investigation has revealed that some of these shafts and chambers were excavated as early as the late twelfth or early thirteenth centuries.