As a result of archaeological excavation, the Dark Ages are now producing examples of water-powered devices, and more attention is being paid to these examples. At Tamworth in Staffordshire the excavation of a watermill shows evidence of a well-designed mill of the Saxon period. These excavations revealed that the mill had been powered by two horizontal waterwheels housed in wooden structures. The mediaeval period gives us our first real insight into the growth of water power in Europe. In England, the Domesday survey of 1086 gives a record of the number of mills in England—some 5000. While all the counties in the country were not surveyed, those that were show a surprising number of mills in relation to the manors, villages and estates.
It must not be taken for granted that all the mills were water driven: hand mills may be indicated by the low level of their rents. Similarly, it must not be assumed that the mills were separate buildings, just that there was more than one waterwheel. The documents, cartularies, leases and grants of land give a greater insight into the way in which the use of water power was developing. All over Europe the abbeys, manors and towns were building watermills, and while most of these were corn mills, there is evidence of the construction of fulling mills, iron mills and saw mills. For example, the most famous drawings of a saw mill were made by Villard de Honnecourt in 1235. A mill built to his drawings was erected as a monument to him at Honnecourt sur Escaut, France. In this mill the waterwheel rotated as an undershot or stream wheel, and by means of cams the reciprocal motion was given to the saw blades. Although it cannot be assumed that this was the first saw mill, it is the first positive document showing the mechanism to have survived.
Although drawings may always have been few in number, it must not be assumed that the knowledge passed slowly from one centre to another. It is well established that there was a great deal of movement of master masons about their own countries, and also about Europe, and it is likely that the knowledge of new methods of millwrighting was passed around in the same way. It is also true that the industrial development of monastic orders, and in particular that of the Cistercians, enabled processes to take place on several of their lands, as industrially-minded monks would be moved about to take their technology to other sites. The working of iron and lead, in the Furness district of Cumbria and the Yorkshire Dales respectively, is an example of the great industrial development pursued by the Cistercians. These religious orders also crossed national boundaries quite easily, and so the development would take place in related sites in other countries. In these countries the local landowners would also take pains to copy the latest monastic developments in machinery.
In terms of the movement of technologists, in Britain there is the example of the deliberate invitation of Queen Elizabeth I to the German miners of the Harz, such as Daniel Hochstetter, to start up the Cumbrian lead, silver and copper mining industry in the Vale of Newlands, with water-driven smelt mills at Brigham near Keswick. From that settlement further members of the German community moved to start smelt works in the Vale of Neath and Swansea in South Wales. The site at Aberdulais (National Trust) is one started by German mining engineers from Keswick in about 1570. The production of iron in England required furnaces which had water-powered bellows and hammers for the refining of the iron blooms produced by the furnaces (see Chapter 2). The large number of hammer ponds in the Weald of Kent and Sussex give an indication of the scale of water power required in mediaeval England to produce wrought iron and the cast-iron guns and shot. The hammer ponds were created to supply the water power for the furnace bellows and for the tilt and helve hammers.
In 1556, the German author Georg Bauer, writing under the pseudonym ‘Georgius Agricola’, wrote De Re Metallica which is effectively a text-book of metal mining and metallurgy (see p. 145). In this large book, well illustrated by wood-block pictures, he sets out the whole process of mining and metal refining on a step-by-step basis. His illustrations show the various stages through which the mining engineer finds his mineral veins, how he digs his shafts and tunnels, and how he uses waterwheels, animal-powered engines and windmills to drain the mines, raise the ore and ventilate the workings. It is quite clear that Bauer was not the inventor of these systems, just that he recorded them from his own studies of central European practice, particularly in the German lead and silver mines. In these areas there are fifteenth- and sixteenth-century religious pictures which are as detailed as the illustrations in De Re Metallica. The painting by Jan Brueghel of Venus at the Forge of about 1600, shows several forms of water-driven forge and boring mills. Obviously, these painters could take only existing installations as their models.
In the English Lake District there are some sites of mineral-dressing works which date from the late sixteenth century. While some have been overlain by later developments, it could be possible to identify waterwheel sites, waterdriven buddles (ore-washing vats) and the like, by archaeological excavation. The dressing works at Red Dell Head, on the flanks of Coniston Old Man and Wetherlam, were abandoned quite early in the 1800s. As the mines grew the mill streams were diverted to other sites where the workings have not been obscured by later developments.
The construction of waterwheels is quite clear in De Re Metallica. Obviously the wheels were made of wood with only the very minimum of iron being used for bearings. Joints would be pegged with dowels rather than fixed with nails. The construction of the millwork, according to these German precedents, would be seen and copied by the local millwrights, when they were concerned with corn mills. This sixteenth-century pattern continued with little improvement until the beginning of the eighteenth century.
Muhammad Aufi
