Horologium

Horologium (Lat.), in med. Europe a number of small campaniform bells with clappers, attached to the rim of a large wheel that was made to revolve, sometimes by rope and crank, sometimes by clockwork. The term is recorded already in the 10th c., when the horologium was used on feast days. Subsequently such wheels were used in the churches of Europe, often attached to the front of the organ. These were later to become known as bell wheel, in France as roue à clochettes, in Ger.-speaking areas as…