‘An automaton is defined as a machine that contains its own principle of motion. Strictly speaking, a clock is an automaton. The notion of an artificial human figure—an “android” as it has come to be called—derives in part from the tradition of the striking jack in the great medieval town clocks, in which the hour would be sounded by a mechanical figure springing into motion with a hammer and gong. That this employment once fell to a living person, the town watchman suggests that here were our first labor-saving robots. But the animated figure, or moving sculpture, can be traced back to ancient Egypt. “At Thebes accordingly, there were statues that spoke and made gestures. The priests made the heads and arms move by devices not as yet clearly explained” we are told by Egyptologist Alexandre Moret, invoking the same combination of mystery, divine intervention, human ingenuity, and mechanics of deception our own monk exhibits. Theater has always been the partner of religion.
The sixteenth century was a period of tremendous mechanical sophistication: the dawning of the scientific revolution. Clockmaking was to become a profession in its own right, separate from its origin in the blacksmith’s art, and its former association with gun- and locksmithing. Precision timekeeping in centuries to come would become crucial to the world shipping trade for its use in determining navigational longitude.  But in its early form, clockmaking was driven less by the problem of measuring time, and more by the astronomer’s efforts to model the locations and motions of “the fixed and moving stars,” that is, to capture the animating principle of the universe.
A significant development—perhaps the significant development—from 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. An early fusee, made of wood, is found in the mechanism of the monk .
The other important development in the mechanical arts was the cam. An ancient device attributed to Archimedes, 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.”
-Elizabeth King, “A Short History of the Relations Between Machines and Divinity (Deus ex Machina).”