In the past, Stuba Communis served as a dining room and a discussion place. It used to be an independent room, which could be entered directly from the cloister through an entrance situated to the right of the stairs. Professors sat at tables arranged in a horseshoe shape. They were silent while eating as the youngest of them would read out loud the Holy Scripture, usually from a lectern. Today, Stuba Communis is still a place for meetings and discussions. Upon entering the room, turn your head to the right to see a grandfather clock with a chime mechanism of zither type, designed by François Bellaire in 1789. On important University’s occasions, such as the opening ceremony of the academic year, the clock plays the melodies of St. Mary's Trumpet Call, which is a traditional, five-note Polish bugle call, and "Poland Is Not Yet Lost", the national anthem of Poland.