Embedded in the centre of the floor of the Loggia del Mercato Nuovo (aka the Loggia del Porcellino) is a small marble circle, the so-called Pietra dello Scandalo (Stone of Scandal).
This was the spot where merchants who were found guilty of commercial malpractices were publicly punished. An offender was tied up and, with his breeches down, his buttocks were struck a number of times against the cold marble.
Several Florentine expressions, such as 'essere con il culo per terra' (to be with your ass/arse on the ground), which are used when someone has financial problems, have their origin in this punishment.
When a merchant was forced to stop trading, on account of financial difficulties, the bench (banca), which he used for trading, was broken up (rotta). This is the origin of the word bankrupt.