page_title: St Mark's Clocktower
section_title: Alterations to the building and clock
hierarchical_section_title: St Mark's Clocktower / Alterations to the building and clock
context_page_description: The Clock Tower in Venice is an early Renaissance building on the north side of the Piazza San Marco, at the entrance to the Merceria. It comprises a tower, which contains the clock, and lower buildings on each side. It adjoins the eastern end of the Procuratie Vecchie. Both the tower and the clock date from the last decade of the 15th century, though the mechanism of the clock has subsequently been much altered. It was placed where the clock would be visible from the waters of the lagoon and give notice to everyone of the wealth and glory of Venice. The lower two floors of the tower make a monumental archway into the main street of the city, the Merceria, which linked the political and religious centre with the commercial and financial centre. Today it is one of the 11 venues managed by the Fondazione Musei Civici di Venezia.
context_section_description: For more detailed and technical information about the clock, see the separate article on the clock.
  By 1531, after the death of Carlo Raineri, the clock was already not working properly. The Council of Ten decided that a permanent keeper must be appointed to live in a wing of the tower and be responsible to keep the clock in working order. Later, in 1551, Jacopo Sansovino, then the architect responsible for St Mark's, was instructed to report on the state of the tower and clock. Major repairs were required, but by 1581, when his son, Francesco, published his description of Venice, all appears to have been in order.
  Shortly before 1663 the clock face was cleaned and the blue and gold colours restored 'like new'. Already by this date the procession of the Magi did not take place daily but only at certain festivals and also every hour of the day on every day while the Ascension Day celebrations lasted.
  By 1750 both tower and clock were badly in need of repair and restoration. In 1751 Giorgio Massari was employed to restore the buildings. In 1755 work started to add two additional floors above the roof terraces of the wings on either side of the tower.  Andrea Camerata took over from Massari in 1757. The eight columns on the front of the ground floor were added in that year, presumably for extra strength.
  Bartolomeo Ferracina was chosen to restore the clock mechanism. He made very extensive alterations, changing the movement from a foliot escapement to a pendulum system, which was much more accurate. The bands in the clock face which had previously shown the apparent movement of the planets round a central earth were removed. The marble circle round the clock face which had been marked, as now, with 24 hours, was covered by a circle showing two series of 12 hours and the Moors were also made to strike the bell in 12-hour cycles, with special rings involving 132 strokes of the bell, at midday and midnight. These changes were complete by 1757. Ferracina then turned his attention to the procession of the Magi, which had apparently not worked for many years, and the new mechanism was inaugurated on Ascension Day 1759. In order to prevent undue wear and tear, this continued to work only during the fortnight after Ascension Day.
  By 1855 repairs were needed again. The top floor of the tower was reinforced and staircases were replaced by iron stairs. In 1858 Luigi de Lucia repaired and made further alterations in the clock mechanism, but preserving the essentials of the changes which had been made by Ferracina.
  At this time a completely new feature was added, so that the time could be read more accurately than was previously possible. Panels were made to appear in the doorways on either side of the Virgin and child, above the clock face. Those on the left show the hour while those on the right show the minutes (changing every 5 minutes), each with white letters on a blue background. The numbers blocked the route of the Magi and additional machinery was designed to lift them out of the way when the processions took place. They originally had gas lights behind them so that they could be read at night. The mechanism operating these numbers caused trouble and was not working properly until 1866. Other improvements and alterations were also made in 1865/66 by Antonio Trevisan and Vincenzo Emo.
  The two 12-hour cycles round the main face of the clock remained until about 1900 when the original 24-hour circle was discovered beneath them and they were removed.
  Further adjustments were made in 1953 and the latest, extensive series of repairs and alterations (some causing controversy amongst horologists) were carried out from 1998 to 2006 (five hundred years after the tower and clock were first completed).
caption: St Mark's Clocktower (Torre dell'Orologio), c.1860/70, by Carlo Ponti
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