Jaki: a Glimpse of Middle Ages Technology

As promised, the wonderful excerpt from Jaki about the medieval monastery. Imagine any tech document giving a fervent little bow of thanks to God, even as a footnote! Why not? We ought to thank Him, especially for our technology:

The wrong is not that engines are too much admired, but that they are not admired enough. The sin is not that engines are mechanical, but that men are mechanical.
[G. K. Chesterton, Heretics CW1:113]

--Dr. Thursday

The chronological definition of the Middle Ages as an epoch from 800 to 1450 provides a logical ground for the historian insofar as the work of evaluation has to be concerned with comparison. Since such a comparison is usually a reference to the preceding culture, the evaluation of the Middle Ages has to be done with an eye on the Roman Empire.

During both the Middle Ages and Roman times material and organizational needs were keenly felt. The Roman Empire had periods of famine, as did the Middle Ages. Both heavily depended on agriculture and relied on manual labor. One was largely served by slaves, the other by serfs. Although the Christian serfs received more humane treatment than did the Roman slaves, the physical conditions of their lives were not much different. At any rate, the pagan Roman landowner had the same interest in a good harvest as did the medieval feudal lord. Why is it then that a major improvement of the plow had to wait for the Middle Ages? Unlike the traditional Roman plow, the medieval plow had, in addition to a vertical knife, a horizontal shear to slice under the sod and a moldboard to turn it over.

Material needs, of course, must have played a part in that very important technological invention, but why then did those needs fail to spur the inventiveness of the Romans of old? They and the Greeks and other ancient nations that made much use of horses in warfare failed to exploit an elementary fact about the horse's anatomy. If a horse is made to pull something by means of a strap around its neck, it not only does so ineffectively but also risks being exposed to strangulation. However, the weight-pulling effectiveness of the horse can be increased fourfold with a breast harness, a medieval invention, as is the nailed horseshoe and the harnessing of horses in front of one another. Their use for plowing the fields is first depicted on the Bayeux tapestry, more famous for showing Halley's comet.

Those medieval inventions made an agricultural revolution. Together with the introduction of three-field crop rotation, they almost doubled the harvest. While many of the physical conditions of medieval serfs remained much the same as those of Roman slaves, they ate much better. A further proof of this is the much wider use of watermills in the Middle Ages compared with Roman times. In England, for instance, a late eleventh-century count of three thousand villages registered almost twice as many watermills, a situation not untypical of other parts of Latin Christendom.

Watermills were needed for more than the grinding of grain. Fullers found a revolutionary use for them, proof of the fact that the clothes worn by medieval people were of better quality than those of their Roman forebears. (Those clothes also had buttons and pockets, two small but most useful advances achieved in the art of dressmaking during the Middle Ages). The use of watermills by fullers is tellingly evidenced in the description of the Abbey of Clairvaux, given about 1180 by a Cistercian monk. The description is an encomium to machinery insofar as it relieves man of hard labor.

In the description of the abbey the visitor approaching it along the river first sees two hills, a vineyard and an orchard respectively, between which nestles the abbey itself. On the near side of the orchard the visitor finds a fishery, made possible by damming the river. From there the river is channeled into the abbey, but in such a way that in case of flood its surplus water would flow around the abbey along an auxiliary canal. From here on, let the anonymous monk take over:

Once the river is let inside the abbey through a sluice, it first rushes against the flour mill, where it is very solicitous and occupies itself in many tasks, both in grinding the grain and in separating the flour from the bran.... But the river is far from being through with its work. It is invited by the fullers who labor next to the flour mills and who rightly demand that just as the river was busy in the mills so that the brethren may be fed, it should also assist the fullers so that the brethren may also be clothed. The river does not decline any work the fullers demand from it. By alternately raising and lowering the heavy stumps, or pestles, or if you wish hammers, or wooden legs (because this name better fits the fullers' jumping style of action), the river relieves them of their really heavy work. Or, if one may inject into a serious topic a remark in a light vein, the river takes upon itself the fullers' punishment for their sins. O God, in your goodness you provide so much respite to your poor servants lest they be overtaken by much sadness! How much relief do you administer to penitents from their sins, lest they feel oppressed by the hardship of their work! The backs of how many horses would be broken and how many men's arms greatly exhausted by a labor from which this river gratuitously dispenses us and without which no clothing, no food would be prepared! The river therefore shares our life while demanding nothing in a way of recompense for its work, which it performs under the blazing sun, except that it may freely leave after it has diligently done its work. It has turned so many big wheels in rapid rotation that it emits froth so that it looks tamed and increasingly so as it moves on.

Instead of following the further course of the river through the numerous other workshops, such as the tannery and laundry, which are also enthusiastically described by that anonymous monk, let us return to his reference to the fullers' up-and-down legwork, now performed by trip-hammers. As well as describing the river's turning "so many big wheels in rapid rotation," he attests to the use of one of the foremost medieval technological inventions, the cam. It does nothing less than transform rotary motion into linear thrust, and vice versa. The medieval introduction of mechanical saws, not mentioned by the monk, is another example of the use of cams.

This is excerpted from Jaki, "Medieval Creativity in Science and Technology" in Patterns or Principles and Other Essays 71-73. I omit the other annotations but the lengthy quote has this note:

My translation is from the Latin text, "Descriptio positionis seu situationis monasterii Clarae-vallensis," in J.-P. Migne, ed., Patrologiae cursus completus. Series latina (Paris: J.-P. Migne, 1844-1864), vol. 185, cols. 569-74.