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ELIZABETH KING | Clockwork PrayerPart III: A Sixteenth-Century Mechanical Masterpiece (continued) A Short History of the Relations Between
Machines and Divinity (Deus ex Machina)
A significant developmentperhaps the significant developmentfrom the medieval town clock, driven by enormous systems of weights, was the emergence of the spiral spring combined with the fusee. A fusee is an ingenious device for making the driving force of a spring constant. Once attributed to Leonardo da Vinci, earlier examples of the fusee have now been found. When wound, a mainspring could now deliver a steady application of tension, rather than a stronger and then progressively weaker force as it ran down. [52] An early fusee, made of wood, is found in the mechanism of the monk (fig. 18). The other important development in the mechanical arts was the cam. An ancient device attributed to Archimedes, [53] the cam reached broad use in the fifteenth century in the striking trains of clocks. A cam is simply a barrel or disk of metal rotated by the gear train. Its outer edge is either studded with short pins, or cut to a calculated profile, and as it turns, one end of a lever, riding against that uneven edge, is set in motion. Called a following arm, the lever translates the cam's calculated profile into reciprocating movements that can be highly precise and carefully timed. Numbers of such levers can operate for example the spring-tensioned linkages to the monk's arms, legs, head, eyes. The cam is thus the memory of the machine, and its profile is the analog information base for generating the exact movements of a given part. [54]
Figure 19 shows the cam that generates the movements of the monk's mouth. Note the thin solitary spike on one side of the disk, distinct from the regular teeth cut around the best of the perimeter. This is the kiss! But even though the spring and fusee consolidated the drive system of a device into a much smaller area, and the cam could store a great deal of information in one component, the early clockmakers did not strive for portability per se. Of the automata that appeared with the rise of clockmaking, most were mechanical elaborations of the striking jack. Or, if they were not connected to a timepiece, they performed in elaborately constructed settings, or on ornate bejewelled pedestals. For me, one of the virtues of the monk, and the few automata like it in history, is that the animating mechanism is entirely contained in the body of the figure. The automaton moves in our world, of its own accord, and not in a miniature world apart, or upon a console we know is full of hidden cams and gears. There is no intermediary prop or set for our imagination, assuring us of the boundaries of what we are about to feel. And of course this is a much more difficult technical feat for the clockmaker. Further still, the monk's motions unfold over time and are compounded, i.e. the automaton continues to do new things from one moment to the next: this would intensify and prolong the duration of its confrontation with a spectator.
For all the lack of any identifying information inside this machine, Todd's drawings of its parts show us the work of a master mechanic with a restrained sense of style. Many components are decoratively chamfered and shaped beyond the necessity of function (figs. 9-12, 19). The complex design of the monk's left arm, with the elbow moving independently of the shoulder, alone is worth respect, and here it is done with an elegance only God was meant to see. There are, in fact, two orders of concealment, for the spectator was not meant to observe the act of winding the drive spring. Todd points out a hidden lever to be used secretly by the operator of the automaton: once wound, the machine would only begin moving after the release of this lever (see fig. 11 "stop work, interrupts fly," and figs. 18, 20). We must envision a scenario, Todd advises us, where a powerful person, or an emissary from that person, is seen to hold the miniature man in his hands, then set it down on the table or floor. Whereupon, very slowly, very deliberately, very irrevocably, it would set out on its own.
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Contributor's notes
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