The cappella dei Mercanti, Negozianti e Banchieri ('chapel of merchants, shopkeepers, and bankers') is a Catholic chapel in the historic city center of Turin.
The chapel, whose construction was authorized during the 16th century, was built at the end of the 1600s and most of the artwork it contains originated in the 1600 and 1700s, in the baroque style.
The walls of the chapel present numerous seventeenth-century paintings, all inspired by the theme of the Biblical Magi. The altar dates back to 1797 and is the work of Michele Emanuele Buscaglione. On either side there are two reliquaries, while on the wall there are three paintings by the Jesuit painter Andrea Pozzo. The baroque frescoed ceiling by Legnanino depicts Heaven, prophets, sibyls and biblical episodes and dates to 1694-1695. The organ on the wall opposite the altar dates back to the eighteenth century.
The sacristy contains several sacred objects, but above all the famous Perpetual Calendar by Giovanni Plana, one of the oldest calculator machines (it is equipped with rotating drums and a transmission system that allows the correct combination of the various information contained in the system) which allows precise calendrical calculation over a period of 4000 years starting from year zero (including the calculation of lunations, days of the week and Christian holidays).
References:The Clementinum is a historic complex of buildings in Prague. Until recently the complex hosted the National, University and Technical libraries, the City Library also being located nearby on Mariánské Náměstí. The Technical library and the Municipal library have moved to the Prague National Technical Library at Technická 6 since 2009. It is currently in use as the National Library of the Czech Republic.
Its history dates from the existence of a chapel dedicated to Saint Clement in the 11th century. A Dominican monastery was founded in the medieval period, which was transformed in 1556 to a Jesuit college. In 1622 the Jesuits transferred the library of Charles University to the Klementinum, and the college was merged with the University in 1654. The Jesuits remained until 1773, when the Klementinum was established as an observatory, library, and university by the Empress Maria Theresa of Austria.