In Venice, a landmark clock returns to action
|By Roderick Conway Morris|
VENICE 11 April 1997
Musei Civici Veneziani
On the roof of the Venice clock tower
two bronze giants strike the hours on a bell.
During its great days the Serenissima, the Most Serene Venetian Republic, seldom stinted in matters of civic self-celebration: witness the Torre dell'Orologio, in Piazza San Marco, one of the most architecturally and mechanically complex tower clocks ever constructed. Unveiled on Feb. 1, 1499, amid general rejoicing, it was described by Marin Sanudo, a contemporary diarist, as "made with great skill, and very beautiful."
Having shown and struck the hours more or less continuously for nearly half a millennium, the clock tower was closed in 1997 for extensive restoration, partly financed by the Swiss watchmakers Piaget. This proved more lengthy than expected, but the clock is now in full working order again. Small groups (book in advance) can view its fascinating interior, and enjoy a 360-degree panoramic view of the city from the roof, where two bronze "Moors" - bearded, half-naked, larger-than-life automatons wielding huge hammers - mark the hours by striking the bell that crowns the edifice.
Many such ancient clocks in Italy have fallen silent for lack of maintenance, said Simonpietro Carraro, an engineer who is now the official keeper of the clock. "The mechanisms of these clocks are works of art in themselves, but it is only now that this is coming to be appreciated once again in Italy.
"Because they were not well maintained, they ceased to be accurate. That is why they were abandoned," Carraro said. "But there is certainly no sense in restoring the machinery unless it works properly afterwards and can continue to do its job."
The central mechanism of the Venice clock operate two faces, one on Piazza San Marco and the other looking down the Merceria, the shopping street that links the square to the Rialto markets. Each face has a marble outer ring inscribed with the 24 hours in Roman numerals. A hand fixed to a revolving inner disc points to the hour. The San Marco face also displays the prevailing zodiacal sign, and a sphere rotating on its axis shows the phases of the moon.
The same mechanism operates the Moors, about 15 meters, or 45 feet, above, who alternately strike the bell with the number of the hours just before and just after the exact hour is indicated on the clock. At midday and midnight two hammers at the rear of the great bell strike 132 times - the total number of blows that the Moors' hammers have struck during the preceding 12 hours.
Also powered by the central works is a spectacle that appears twice a year, on the Feast of the Epiphany, or Twelfth Night, and Ascension Day. On those days, gilded doors automatically open every hour to left and right of a statue of the Madonna and Child set in a niche above the Piazza clock face. From the left emerges a procession of articulated polychrome wooden statues representing the Three Kings led by an Angel. As the angel passes the Virgin, the figure raises its trumpet to its lips, and the Three Kings bow, doffing their turbans and crowns, before disappearing into the right-hand door, which closes behind them.
The main works of the clock were renewed in the middle of the 18th century, and a radical modification was carried out in 1858, when Luigi De Lucia installed additional "digital" displays of the hours and minutes in the apertures to the left and right of the statue of the Madonna, complementing the traditional clock faces. This was quite revolutionary for the times, although the system is something of a hybrid, the hours being shown in Roman numerals and the minutes (which change every five minutes) in Arabic numbers.
The system is operated by two 12-faced drums that are rotated by the principal clock machine, and the numbers are back lit to make them visible at night.
"Luigi De Lucia was a mechanical engineer, not a clockmaker," Carraro said. "To make the drums work, he sacrificed the correct functioning of the clock by making modifications to the central mechanism. After which it did not work perfectly as before, a situation that led to further improvised modifications."
The latest restoration of the clock involved the dismantling of over 3,000 metal components and their temporary removal from the tower. The work was undertaken by Alberto Gorla, a Mantuan clockmaker, mechanical inventor and expert on antique timepieces, in collaboration with the horological historian Giuseppe Brusa. The restoration aimed to return the central mechanism as closely as possible to its mid-18th-century state while still allowing the 19th-century digital drums to operate.
Gorla's substantial innovation has been the addition of an ingenious system of chains attached to a new set of winding weights to power the clock. When the weights fall far enough, they touch sensors which activate small electric motors to raise them back into position to begin again their slow descent. These additions are housed in the room below the main machine room, where once the clock's custodians lived, minimizing their impact on the appearance of the majestic antique clock mechanism; and the hand-cranking devices that were formerly used are all still in place, so it remains possible to wind the clock in traditional fashion.
The restoration has not been without its critics, who say that the overhaul has been excessively radical and that the use of some modern, machine-made, components has compromised the integrity of the original structure.
Carraro defends the work, however, noting that all parts removed from the clock have been documented and preserved.
As for the sensors and the electrical winding system, "they could easily be removed entirely without damaging the clock, if such a decision were to be made in the future."
First published: International Herald Tribune
© Roderick Conway Morris 1975-2016