The rotating clock movement

North of Italy has a great tradition for mechanical horlogy at Leonardo's time. Public clocks are present in lot of cities and watchmakers are the great artisans of the moment. Leonardo da Vinci is interested by their art, and particulary by continuous mechanism. Springs fascinate the florentine engineer because it control movement with the better precision at the time. Leonardo da Vinci works on springs boxes and systems to assure a constant speed and a continuous mechanism.