CLOCK. — From antiquity there is evidence of instruments designed for measuring time that were applied to buildings; however, the clock understood as an element that is also decorative in architecture is a rather later creation.
In the Middle Ages, even before the need for clocks in public buildings for civic use, there arose the need for an exact division of time within religious communities to regulate the life of monks and for the canonical hours. It therefore seems certain that this was the reason why the first medieval clocks were installed inside rather than outside churches; only later were they equipped with bells and external dials, thus serving also as public clocks. Moreover, they gradually became increasingly complex in their internal mechanisms and in their dials adorned with astronomical or allegorical figures and animated by automata, which at the striking of the hours perform certain gestures.
The most important examples of medieval clocks of artistic interest are found in France and Germany. Beauvais Cathedral possesses an internal clock of which the original mechanism is still preserved; it is a simplified version of the Venetian type. It is this Venetian clock, the Italian one that most closely resembles the transalpine type: the building, erected by Mauro Coducci in 1496–99, houses a large astronomical dial surmounted by a small loggia in which, at the striking of the hours, the Magi appear to pay homage to the Virgin and Child; all of this is finally topped by a bell on which two bronze figures strike the hours with a long hammer. Naturally, in the 16th century and in the centuries that followed, there are many clocks on bell towers and facades or towers of palaces, but generally they are of little artistic interest, except for the Baroque ones that form part of, as a decorative-scenographic element, the complex architecture of the period (Rome, S. Agnese in Piazza Navona, the Collegio dei Filippini, S. Pietro; Superga sanctuary, etc.), or some from the last century, such as that of the Houses of Parliament in London (1859). — See pl. XXII.